Long covid outcomes at one year after mild SARS-CoV-2 infection: nationwide cohort study


Aims To find out the medical sequelae of lengthy covid for a 12 months after an infection in sufferers with gentle illness and to judge its affiliation with age, intercourse, SARS-CoV-2 variants, and vaccination standing.

Design Retrospective nationwide cohort research.

Setting Digital medical information from an Israeli nationwide healthcare organisation.

Inhabitants 1 913 234 Maccabi Healthcare Providers members of all ages who did a polymerase chain response check for SARS-CoV-2 between 1 March 2020 and 1 October 2021.

Predominant consequence measures Danger of an proof based mostly listing of 70 reported lengthy covid outcomes in unvaccinated sufferers contaminated with SARS-CoV-2 matched to uninfected individuals, adjusted for age and intercourse and stratified by SARS-CoV-2 variants, and threat in sufferers with a breakthrough SARS-CoV-2 an infection in contrast with unvaccinated contaminated controls. Dangers had been in contrast utilizing hazard ratios and threat variations per 10 000 sufferers measured through the early (30-180 days) and late (180-360 days) time durations after an infection.

Outcomes Covid-19 an infection was considerably related to elevated dangers in early and late durations for anosmia and dysgeusia (hazard ratio 4.59 (95% confidence interval 3.63 to five.80), threat distinction 19.6 (95% confidence interval 16.9 to 22.4) in early interval; 2.96 (2.29 to three.82), 11.0 (8.5 to 13.6) in late interval), cognitive impairment (1.85 (1.58 to 2.17), 12.8, (9.6 to 16.1); 1.69 (1.45 to 1.96), 13.3 (9.4 to 17.3)), dyspnoea (1.79 (1.68 to 1.90), 85.7 (76.9 to 94.5); 1.30 (1.22 to 1.38), 35.4 (26.3 to 44.6)), weak point (1.78 (1.69 to 1.88), 108.5, 98.4 to 118.6; 1.30 (1.22 to 1.37), 50.2 (39.4 to 61.1)), and palpitations (1.49 (1.35 to 1.64), 22.1 (16.8 to 27.4); 1.16 (1.05 to 1.27), 8.3 (2.4 to 14.1)) and with important however decrease extra threat for streptococcal tonsillitis and dizziness. Hair loss, chest ache, cough, myalgia, and respiratory issues had been considerably elevated solely through the early part. Female and male sufferers confirmed minor variations, and kids had fewer outcomes than adults through the early part of covid-19, which largely resolved within the late interval. Findings remained constant throughout SARS-CoV-2 variants. Vaccinated sufferers with a breakthrough SARS-CoV-2 an infection had a decrease threat for dyspnoea and related threat for different outcomes in contrast with unvaccinated contaminated sufferers.

Conclusions This nationwide research means that sufferers with gentle covid-19 are in danger for a small variety of well being outcomes, most of that are resolved inside a 12 months from prognosis.


Greater than two years into the worldwide pandemic, SARS-CoV-2 has induced greater than 600 million confirmed instances of covid-19 worldwide, leading to greater than 6.5 million deaths as of November 2022.1 Because the starting of the pandemic, a number of variants of the virus have been recognized, amongst which 5 had been outlined as variants of concern by the World Well being Group: alpha, beta, gamma, delta, and omicron.2 These variants differ in transmissibility, illness course, and illness severity.3 Moreover, they could have an effect on illness diagnostics, lower susceptibility to therapies, cut back vaccine mediated safety from extreme sickness, and doubtlessly have an effect on the long run well being outcomes after SARS-CoV-2 an infection, also called lengthy covid outcomes.

The acute illness brought on by SARS-COV-2 is various and may vary from asymptomatic or gentle respiratory illness to a multisystem life threatening syndrome.4 Most instances resolve inside two to 4 weeks of the preliminary signs’ look; nevertheless, an rising physique of proof exhibits long run sequelae, additionally known as lengthy covid.5678910111213141516171819 The medical definition of lengthy covid continues to be evolving, however to this point it has been outlined as persistent signs or look of latest signs past 4 weeks from the prognosis of main covid-19, which can’t be attributed to an alternate situation.2021 It might current with numerous multi-organ signs comparable to dyspnoea, fatigue, myalgia, cough, cognitive dysfunction, chest ache, and palpitations, which differ in prevalence and severity. The immunological mechanisms and pathophysiology of lengthy covid are nonetheless being studied, however some threat elements have already been recognized, together with older age; pre-existing comorbidities comparable to weight problems, heart problems, continual lung illness, kidney illness, hypertension, and diabetes mellitus; preliminary illness severity; and feminine intercourse.567111522232425 As of March 2022 an estimated 1.5 million individuals within the UK (2.4% of the inhabitants) accomplished a self-reported survey describing lengthy covid signs persisting for greater than 4 weeks after the preliminary an infection, primarily fatigue, shortness of breath, lack of odor, lack of style, and issue concentrating.26

Present efforts give attention to assessing the prevalence of lengthy covid and monitoring its medical manifestations; nevertheless, these efforts are hampered by non-standardised research designs, variations in knowledge high quality, and the shortage of applicable comparative strategies in most research.13 A lot of the knowledge so far got here from inhabitants surveys with out controls, and the observational research of huge datasets additionally lack comparability with an applicable management group. To offer environment friendly steady remedy and forestall antagonistic occasions associated to potential long run results and delayed signs of covid-19, figuring out the magnitude and severity of this phenomenon and distinguishing it from related medical manifestations that happen usually or following infections with different pathogens is crucial.

Excessive international efforts to mitigate transmission of SARS-CoV-2 and forestall deterioration to extreme sickness had been centered on creating a vaccine rapidly. So, lower than a 12 months into the pandemic, the primary mRNA based mostly covid-19 vaccine was developed, adopted by a global scale vaccination marketing campaign.2728 Worldwide assessments of vaccine effectivity have proven {that a} two dose routine of the BNT162b2 vaccine is extremely efficient throughout all age teams (≥16 years) in stopping symptomatic and asymptomatic SARS-CoV-2 infections and covid-19 associated hospital admissions, extreme illness, and dying. Moreover, administration of a 3rd booster dose has additionally been proven to be efficient in lowering covid-19 instances and extreme sickness.2930313233 Regardless of the cumulative proof of the covid-19 vaccines’ capacity to cut back illness burden and severity, whether or not immunisation protects in opposition to the long run sequelae of breakthrough covid-19 an infection continues to be unknown.343536

The primary goal of this research was to match the long run incidence of a giant set of well being outcomes between uninfected individuals and sufferers with gentle covid-19. Moreover, we studied the associations between gentle covid-19 and lengthy lasting well being outcomes in numerous age and intercourse subgroups and after an infection with completely different SARS-CoV-2 variants. Lastly, we assessed the variations in lengthy covid medical sequelae between vaccinated and unvaccinated individuals who recovered from a light illness.


Examine settings

On this research, we analysed digital well being information from the excellent database of Maccabi Healthcare Providers (MHS), the second largest well being upkeep organisation in Israel. Israeli residents are required to turn out to be members of one of many 4 well being upkeep organisations within the nation. MHS covers 1 / 4 of the Israeli inhabitants, with a nationally consultant sociodemographic distribution. The database accommodates medical knowledge of a steady inhabitants of greater than 2.5 million individuals collected since 1993 with an roughly 1% annual attrition charge. It consists of longitudinal knowledge for all covid-19 diagnoses, deterioration, restoration, and post-recovery follow-up in outpatient clinics. Detailed demographic info, diagnoses, continual illness registries, administrative billing codes, remedy dispensations, full laboratory knowledge from a single central laboratory, and all different complementary companies which can be provided by the well being fund had been all included within the dataset. As well as, the Israeli Ministry of Well being collects and shares covid-19 knowledge with all of the Israeli well being funds, together with the outcomes of all SARS-CoV-2 polymerase chain response (PCR) testing, admissions to hospital with covid-19, and covid-19 immunisations dates. PCR checks had been provided to all Israeli residents freed from cost without having for referral all through the whole research interval. Consequently, 76% of MHS’ members had a minimum of one PCR check through the research interval.

Eligibility standards (research inhabitants)

The research included all MHS members with a PCR check for SARS-CoV-2 (constructive or destructive) between 1 March 2020 and 1 October 2021, with a minimum of one 12 months’s membership within the well being organisation earlier than the check. We excluded from the research all sufferers who had been admitted to hospital with covid-19 through the 30 days after an infection, aiming to research lengthy covid in sufferers with gentle illness. The factors for hospital admission of sufferers with covid-19 in Israel had been constant all through the research interval, in accordance with pointers set by the Ministry of Well being.37 To differentiate between new outcomes and present ones, we additional excluded sufferers who had the thought of consequence earlier than the PCR check (index date). Nonetheless, the exclusion standards had been completely different for various consequence varieties: for outcomes reflecting a continual state (for instance, bronchial asthma, diabetes), we excluded sufferers with any incidence of that consequence up to now; for outcomes reflecting a short lived state (for instance, cough, weak point) we excluded sufferers with incidence of that consequence within the earlier 12 months.

Examine design

On this retrospective cohort research, we evaluated well being outcomes in unvaccinated individuals with SARS-CoV-2 an infection in contrast with individuals with out SARS-CoV-2 an infection, controlling for age and intercourse and with stratification by SARS-CoV-2 variants, and in vaccinated versus unvaccinated individuals contaminated with SARS-CoV-2. We used signs and diagnoses recorded by physicians as ICD-10 (worldwide classification of illnesses, tenth revision) codes to acquire info on outcomes doubtlessly associated to lengthy covid. These outcomes could possibly be documented repeatedly by the physicians, permitting longitudinal seize of the sufferers’ medical standing. We matched eligible sufferers with a primary constructive PCR check for SARS-CoV-2 in a one-to-one ratio to eligible sufferers with a destructive PCR check and no earlier constructive PCR check. To beat biases associated to an infection, we utilized each matching and weighting strategies. We utilized actual matching for main confounders to make sure tight steadiness and inverse weighting through propensity scores for weaker confounders to retain enough pattern dimension. We utilized actual matching on age (12 months of start), intercourse, month of check, and covid-19 immune standing on the day of the PCR check (unvaccinated, partially vaccinated, second dose covid-19 vaccine, and covid-19 booster). We used solely knowledge obtainable on or earlier than the day of the PCR check when making use of the coupling. If through the follow-up interval an unexposed affected person (PCR destructive) was contaminated with SARS-CoV-2, we censored the follow-up of the whole matched pair. This affected person then re-started follow-up as an uncovered affected person (PCR constructive) and was matched to a brand new unexposed particular person.38 We calculated the propensity scores through a logistic regression mannequin for the likelihood of being SARS-CoV-2 constructive, together with the next pre-existing continual situations: heart problems, immune deficiency, pre-diabetes standing, diabetes, hypertension, continual kidney illness, most cancers, weight problems, and continual obstructive pulmonary illness, in addition to alcohol consumption, smoking standing, sector (basic secular Israeli inhabitants, Israeli-Arab, ultra-Orthodox Jewish), residential socioeconomic stage (scale from 1 to 10 categorised into three teams: low 1-3, medium 4-6, excessive 7-10), and historical past of influenza vaccination within the earlier three years. The residential sector and socioeconomic scores got here from the Israel Central Bureau of Statistics and extra beforehand described knowledge sources.3940 The follow-up of the matched pair was terminated on the earliest of the next situations: finish of the research interval, dying, leaving MHS, or a second an infection of the uncovered affected person decided by a constructive PCR check greater than 90 days after the primary an infection date.

Firstly, to quantify the danger for long run well being outcomes related to gentle SARS-CoV-2 an infection in unvaccinated individuals, we analysed a sub-cohort of unvaccinated SARS-CoV-2 contaminated and non-infected pairs throughout wild-type virus and alpha variant durations and in contrast all reported covid-19 outcomes between pairs (we didn’t embody the delta variant owing to inadequate follow-up). We categorised age into six age teams: three kids’s subgroups (0-4, 5-11, and 12-18 years) and three adults’ subgroups (19-40, 41-60, and >60) (supplementary desk S2a). The follow-up interval was from the second to twelfth month after the PCR check, to focus on outcomes associated to covid-19 after the acute interval (first month).

Secondly, to evaluate the danger for long run well being outcomes in sufferers with gentle covid-19 brought on by completely different SARS-CoV-2 variants, we used the identical sub-cohort of paired unvaccinated individuals and utilized a further match by age and intercourse between pairs contaminated with every variant. We then analysed covid outcomes by evaluating wild-type SARS-CoV-2 with the alpha (B.1.1.7) variant and by evaluating wild-type SARS-CoV-2 and the alpha variant with the delta (B.1.617.2) variant. We categorised the infections into variants on the idea of the PCR check date and based on the dominant variant at the moment. The dominant variant of every interval was declared by the Israeli Ministry of Well being (variant comprised ≥90% of instances on the peak interval on the idea of genetic sequencing): wild sort SARS-CoV-2 was dominant from 1 March 2020 to 1 November 2020, the alpha variant was dominant from 2 November 2020 to 1 Could 2021, and the delta variant was dominant from 2 Could 2021 to 1 October 2021 (fig 1; supplementary determine S1).414243

Fig 1

Examine inhabitants and cohort choice. Schematic illustration of cohort and sub-cohorts choice. Individuals who had been included in matched destructive SARS-CoV-2 cohort and examined constructive throughout research had been added to constructive cohort and re-matched. SARS-CoV-2 variants had been decided based on variant dominance at time of polymerase chain response (PCR) testing

Thirdly, to judge the affiliation between the vaccination standing of contaminated sufferers and long run well being outcomes, we analysed a sub-cohort of vaccinated and unvaccinated SARS-CoV-2 contaminated sufferers (≥12 years outdated), through the alpha and delta variants durations, with a follow-up time of 30-90 days. Full 90 day follow-up was obtainable for 99% of the sufferers within the cohort. We thought of sufferers vaccinated if an infection occurred later than 14 days after the second dose of vaccine, as beforehand described,44 and in accordance with Facilities for Illness Management and Prevention (CDC) pointers. We utilized related matching and weighting strategies to these used for evaluating SARS-CoV-2 contaminated and non-infected pairs to match vaccinated and unvaccinated pairs.


We in contrast incidence charges of a number of outcomes that is perhaps related to covid-19 within the quick and long run after an infection: signs, new diagnoses of continual illnesses, new acute problems, and new infectious illnesses. An entire listing of the research outcomes is supplied in supplementary desk S1. The set of outcomes for this research got here from a number of assets together with the CDC studies,21 WHO publications,45 Israeli Ministry of Well being publications, and extra scientific studies (all referenced in supplementary desk S1). As well as, we held consultations with an infectious illness specialist and household physicians at MHS and with physicians from a devoted restoration clinic established for the advantage of covid-19 sufferers with long run signs. To acquire details about the outcomes, we used diagnoses reported by physicians as ICD-10 codes within the sufferers’ medical recordsdata. Data of diagnoses that had been included in free textual content solely and never documented as ICD-10 codes weren’t included within the research. Extraordinarily uncommon outcomes (fewer than 10 occasions total, in each teams) are introduced solely in supplementary tables S1, S2b, and S2c. We categorised the outcomes into two teams: recurrent occasions and first time occasions. For recurrent occasions, we took all of the situations wherein the prognosis was registered within the medical recordsdata to estimate the size of time the affected person skilled the prognosis. For first time occasions, we took the primary date through the follow-up interval.46

As SARS-CoV-2 is a respiratory virus, presenting important lingering respiratory associated signs, we additionally analysed extra particularly studies of pulmonary well being outcomes and assessed the severity and well being associated burden by extracting the related disbursed medicine for obstructive airway illness (Anatomical Therapeutic Chemical code R03).

Statistical evaluation

We calculated hazard ratios and 95% confidence intervals for the constructive versus destructive covid-19 teams within the durations of 30-90 days, 30-180 days, and 180-360 days from an infection, utilizing inverse propensity rating weighting Cox regression. We utilized an analogous evaluation for SARS-CoV-2 contaminated sufferers, with hazard ratios and 95% confidence intervals of vaccinated versus unvaccinated sufferers for every consequence, utilizing inverse propensity rating weighting to steadiness the teams. We assessed potential impact modifications by means of inclusion of interplay phrases within the mannequin reflecting hazard ratios that differed by age and intercourse. We utilized false discovery charge correction inside every research goal to manage for a number of hypotheses inside the goal. We introduced false discovery charge adjusted P values as Q values and took 0.05 because the cut-off for significance.

To estimate the burden of covid-19 outcomes, we calculated threat variations by utilizing time to occasion Kaplan-Meier evaluation with inverse propensity rating weighting. We calculated the danger variations per 10 000 individuals for the durations of 30-180 days, 30-360 days, and 180-360 days, to distinguish between quick and long run outcomes. We examined the heterogeneity of hazard ratios between variants and sexes through a z rating calculated because the distinction between the 2 logs hazard ratio divided by the usual error. We used Python model 3.1 with the stats mannequin, causallib, and liflelies packages for analyses.

Affected person and public involvement

Owing to the character of this research and knowledge privateness constraints, sufferers and members of the general public weren’t concerned within the design, evaluation, and interpretation of the research. We intention to interact the general public by means of huge dissemination of the findings in numerous well being organisations and media shops.


Examine inhabitants

The research cohort comprised 1 913 234 MHS members who did a SARS-CoV-2 PCR check between 1 March 2020 and 1 October 2021 (fig 1). Comply with-up knowledge for hospital admissions and well being outcomes had been obtainable till 1 January 2022. We had 299 885 eligible members with full knowledge, who examined constructive for SARS-CoV-2 and had not been admitted to hospital with covid-19 a month after their prognosis. Of those, we matched 299 870 to individuals who examined destructive and had related age, intercourse, time of check, and vaccination standing (see Strategies part). The examined cohort had a median age of 25 years and 50.6% had been feminine (desk 1). The demographic proportion of the sectors and socioeconomic ranges confirmed some variations between SARS-CoV-2 constructive and destructive individuals. The SARS-CoV-2 constructive group had an elevated illustration of the Jewish Orthodox sector (22.1% v 7.9% within the SARS-CoV-2 destructive group) and the low socioeconomic standing stage (31.9% v 16.9% within the SARS-CoV-2 destructive group). Propensity rating weighting eradicated these variations between the teams. The prevalence of comorbidities in SARS-CoV-2 constructive and destructive individuals was related, and the propensity rating weighting corrected the minimal variations noticed between the teams.

Desk 1

Baseline traits of research cohort. Values are numbers (percentages) until acknowledged in any other case

Medical sequelae of covid-19 in unvaccinated sufferers

We quantified the long run medical sequelae related to a light SARS-CoV-2 an infection in unvaccinated sufferers for 70 well being situations that had been reported within the literature as being related to covid-19 and grouped them below 4 classes: persistent signs, acute diagnoses, infectious illnesses, and new diagnoses of continual situations (supplementary desk S1). Uniquely on this research, we evaluated threat longitudinally utilizing each hazard ratios and threat variations in a matched sub-cohort of SARS-CoV-2 constructive and destructive unvaccinated individuals supplementary (desk S2a; fig 2; fig 3) throughout two time durations after a constructive PCR check: the early part (30-180 days; supplementary desk S2b) and the late part (180-360 days; supplementary desk S2c).

Fig 2
Fig 2

Danger for long run well being outcomes after SARS-CoV-2 an infection in sufferers with gentle illness. Hazard ratios and threat variations per 10 000 sufferers of reported well being outcomes (persistent signs) in unvaccinated SARS-CoV-2 contaminated sufferers with gentle covid-19 throughout early and late durations

Fig 3
Fig 3

Danger for long run well being outcomes after SARS-CoV-2 an infection in sufferers with gentle illness. Hazard ratios and threat variations per 10 000 sufferers of reported well being outcomes (acute diagnoses, infectious illnesses, continual situations) in unvaccinated SARS-CoV-2 contaminated sufferers with gentle covid-19 throughout early and late durations. TIA=transient ischaemic assault

The well being outcomes that signify lengthy covid confirmed a big enhance in each early and late phases. Anosmia and dysgeusia (early: hazard ratio 4.59 (95% confidence interval 3.63 to five.8) and threat distinction 19.6 (95% confidence interval 16.9 to22.4); late: 2.96 (2.29 to three.82) and 11.0 (8.5 to 13.6), respectively), focus and reminiscence impairment (early: 1.85 (1.58 to 2.17) and 12.8 (9.6 to 16.1); late: 1.69 (1.45 to 1.96) and 13.3 (9.4 to 17.3)), dyspnoea (early: 1.79 (1.68 to 1.90) and 85.7 (76.9 to 94.5); late: 1.3 (1.22 to 1.38) and 35.4 (26.3 to 44.6)), weak point (early: 1.78 (1.69 to 1.88) and 108.5 (98.4 to 118.6), late: 1.30 (1.22 to 1.37) and 50.2 (39.4 to 61.1)), palpitations (early: 1.49 (1.35 to 1.64) and 22.1 (16.8 to 27.4); late: 1.16 (1.05 to 1.27) and eight.3 (2.4 to 14.1)), streptococcal tonsillitis (early: 1.18 (1.09 to 1.28) and 13.4 (6.8 to 19.9); late: 1.12 (1.05 to 1.20) and 16.6 (7.4 to 25.9)), and dizziness (early: 1.14 (1.06 to 1.23) and 11.4 (4.7 to 18.1); late: 1.17 (1.09 to 1.26) and 16.7 (8.6 to 24.8)) lingered a 12 months after an infection. To estimate the general burden of those outcomes after SARS-CoV-2 an infection, we assessed the danger distinction for the entire 12 months of follow-up after the acute illness part (30-360 days; supplementary desk S2d). The yearly burden measured was highest for weak point (threat distinction 136.0, 121.8 to 150.1), dyspnoea (107.4, 95.4 to 119.4), and streptococcal tonsillitis (31.8, 20.7 to 42.8).

Some well being outcomes had been considerably elevated solely through the early part. These had been respiratory issues (situations grouped below the ICD-10 code J98) (hazard ratio 2.4, 1.67 to three.44; threat distinction 3.7, 2.3 to five.3), hair loss (1.75, 1.59 to 1.93; 31.6, 26.2 to 36.9), chest ache (1.41, 1.33 to 1.49; 56.3, 47.0 to 65.7), myalgia (1.24, 1.15 to 1.35; 17.5, 11.2 to 23.8), and cough (1.09, 1.04 to 1.14; 22.2, 9.7 to 34.6). We additionally noticed a big enhance within the hazard ratio for fatty liver (1.31, 1.13 to 1.52) through the early time interval. To ascertain whether or not the elevated threat for this prognosis was biased attributable to a better testing charge, we did further evaluation and confirmed that individuals who examined constructive for SARS-CoV-2 had extra liver enzyme checks than did those that examined destructive, resulting in elevated detection of this asymptomatic prognosis (supplementary determine S2). We noticed an analogous enhance for glucose and haemoglobin, supporting the speculation that folks with covid-19 had been examined extra usually. Normalising by the testing charge yielded a non-significant distinction between the 2 teams.

The hazard ratio for arthralgia was considerably elevated through the late interval. Nonetheless, the relative distinction was related through the two time durations (early: hazard ratio 1.11 (1.02 to 1.20) and threat distinction 7.3 (1.3 to 13.4); late: 1.17 (1.08 to 1.27) and 13.8 (6.6 to 21.1) respectively).

We noticed a considerably decrease threat for lymphadenopathy in individuals with covid-19 within the early part (hazard ratio 0.81, 0.72 to 0.91). To find out whether or not this was a reported consequence related to the SARS-CoV-2 an infection and never a facet impact brought on by covid-19 vaccination throughout follow-up, we did further evaluation. We measured increased vaccination charges amongst SARS-CoV-2 destructive individuals (29%; 62 558/214 046) in contrast with these testing constructive (15%; 31 063/214 046), who had been much less more likely to get vaccinated after restoration. Verification was carried out for lymphadenopathy, censoring every exposed-unexposed pair as soon as a vaccination occasion occurred. The ensuing hazard ratio (0.98, 0.84 to 1.14) was not considerably completely different between SARS-CoV-2 constructive and destructive individuals.

As SARS-CoV-2 is a respiratory virus, presenting important lingering respiratory associated signs, we analysed extra particularly studies of pulmonary well being outcomes and assessed the severity and well being associated burden by analysing prescriptions for the related medicine. Our evaluation indicated that individuals who examined constructive for SARS-CoV-2 had an elevated threat for each pulmonary illness handled with prescribed drugs (threat distinction 25.7, 18.1 to 33.3) and pulmonary illness not handled with prescribed drugs (92.6, 81.3 to 103.9). However, the share of drug prescriptions amongst sufferers recognized as having pulmonary illness was related between SARS-CoV-2 constructive and destructive sufferers (23.8% (1157/4860) v 24.3% (828/3408)), indicating that the severity of pulmonary situations after SARS-CoV-2 an infection was much like pulmonary situations in individuals with out SARS-CoV-2 an infection (see supplementary desk S3).

To raised perceive the timeline of the well being outcomes that modified considerably after SARS-CoV-2 an infection, we analysed the studies month-to-month (fig 4; supplementary desk S2e). The outcomes had completely different month-to-month hazard ratios through the first 12 months after a prognosis of covid-19. Hazard ratios for dyspnoea, palpitations, weak point, cough, and chest ache peaked near an infection and declined from the second month onward. Whereas the hazard ratios for dyspnoea and weak point in contaminated sufferers remained increased all through the late part (dyspnoea: hazard ratio 2.26 (2.06 to 2.47) on the second month to 1.23 (1.10 to 1.38) on the twelfth month; weak point: 2.14 (1.97 to 2.31) to 1.40 (1.27 to 1.55)), these for palpitations and chest ache returned to baseline inside eight months of prognosis of covid-19 and that for cough by the fourth month. Anosmia and dysgeusia was essentially the most distinctive consequence amongst contaminated sufferers, peaking six months after prognosis (hazard ratio 5.58, 4.02 to 7.76) after which slowly declining, remaining considerably increased than in uninfected individuals even a 12 months after an infection (2.37 (1.52 to three.70) on the twelfth month). Equally, focus and reminiscence impairment had important hazard ratios all year long after prognosis, peaking at 4 months (2.08, 1.71 to 2.53) and slowly declining. Hair loss had distinct consequence reporting kinetics, elevating slowly, peaking at 4 months post-infection (hazard ratio 2.17, 1.92 to 2.44), after which declining to achieve baseline seven months post-infection. The hazard ratio for streptococcal tonsillitis was elevated in SARS-CoV-2 constructive sufferers from 4 to eight months after prognosis, peaking at six months (hazard ratio 1.27, 1.15 to 1.40).

Fig 4
Fig 4

Month-to-month threat of serious reported outcomes in unvaccinated contaminated sufferers. Hazard ratios (with 95% confidence intervals) for reported well being outcomes that had been considerably completely different for unvaccinated individuals contaminated with SARS-CoV-2 in contrast with matched uninfected individuals. Month-to-month threat of reported outcomes was evaluated longitudinally throughout early and late durations

Lengthy covid medical sequelae in numerous age and intercourse subgroups

As age was an necessary indicator for illness severity, we in contrast well being outcomes by age subgroups for a 12 months after an infection to determine whether or not age modified the affiliation between gentle covid-19 and long run outcomes. Sufferers of all age teams who examined constructive for SARS-CoV-2 had a number of well being outcomes with considerably elevated hazard ratios (supplementary tables S4a-l; fig 5).

Fig 5
Fig 5

Danger of serious reported outcomes in numerous age subgroups. Hazard ratios and threat variations (with 95% confidence intervals) for all reported well being situations (supplementary tables S4a-l) had been evaluated throughout early and late (orange) durations

The 41-60 years subgroup had the very best variety of lengthy covid well being outcomes that had been considerably elevated in each time durations through the 12 months after an infection (supplementary tables S4e and S4k): anosmia and dysgeusia (early: hazard ratio 4.05 (3.11 to five.28) and threat distinction 32.2 (23.9 to 40.5); late: 3.1 (2.26 to 4.25) and 22.5 (14.6 to 30.4), respectively), dyspnoea (early: 2.57 (2.30 to 2.87) and 166.5 (143.9 to 189.1); late: 1.59 (1.42 to 1.78) and 72.8 (51.3 to 94.3)), weak point (early: 2.15 (1.98 to 2.34) and 233.7 (203.4 to 264.1); late: 1.35 (1.24 to 1.47) and 88.8 (58.3 to 119.3)), focus and reminiscence impairment (early: 1.9 (1.54 to 2.33) and 25.2 (14.9 to 35.5); late: 1.93 (1.61 to 2.3) and 29.2 (17.7 to 40.7)), and palpitations (early: 1.64 (1.43 to 1.89) and 49.1 (33.0 to 65.2); late: 1.22 (1.06 to 1.4) and 20.0 (3.1 to 37.0)). Though not considerably elevated within the early part, dizziness and arthralgia confirmed considerably increased threat through the late part (dizziness: hazard ratio 1.25 (1.13 to 1.38) and threat distinction 42.0 (18.0 to 66.1); arthralgia: 1.26 (1.13 to 1.4) and 39.6 (16.9 to 62.3), respectively).

The youthful adults subgroup of 19-40 years (supplementary tables S4d and S4j) confirmed considerably elevated threat in each phases through the first 12 months after gentle covid-19 for anosmia and dysgeusia (early: hazard ratio 5.23 (3.48 to 7.87) and 26.9 (21.3 to 32.6); late: 3.38 (2.13 to five.37) and 13.2 (8.5 to 17.9), respectively), dyspnoea (early: 2.51 (2.19 to 2.89) and 90.7 (77.7 to 103.7); late: 1.55 (1.33 to 1.81) and 37.1 (24.7 to 49.5)), focus and reminiscence impairment (early: 2.23 (1.65 to three.01) and 15.7 (10.0 to 21.5); late: 2.36 (1.71 to three.27) and 17.4 (11.0 to 23.8)), and weak point (early: 1.65 (1.51 to 1.8) and 121.7 (100.8 to 142.5); late: 1.32 (1.2 to 1.46) and 67.3 (45.1 to 89.5)).

Within the older age group >60 years (supplementary tables S4f and S4l), we noticed elevated threat through the early part for hair loss (hazard ratio 2.51, 1.78 to three.53; threat distinction 69.6, 43.1 to 96.1), weak point (1.50, 1.30 to 1.73; 166.2, 101.0 to 231.3), dyspnoea (1.51, 1.30 to 1.75; 138.9, 81.0 to 196.9), and chest ache (1.26, 1.08 to 1.47; 87.1, 23.7 to 150.6). Solely dyspnoea remained considerably elevated all through the late part (hazard ratio 1.42, 1.20 to 1.67; threat distinction 105.3, 49.6 to 160.9).

Within the 12-18 years subgroup (supplementary tables S4c and S4i), streptococcal tonsillitis remained considerably excessive throughout early and late phases (early: hazard ratio 1.68 (1.40 to 2.02) and threat distinction 37.4 (21.5 to 53.3); late: 1.55 (1.33 to 1.81) and 57.3 (33.2 to 81.4) respectively) whereas anosmia and dysgeusia (hazard ratio 23.50, 5.48 to 100.86; threat distinction 15.6, 10.1 to 21.0), dyspnoea (1.70, 1.36 to 2.12; 32.4, 17.9 to 46.8), and weak point (1.66, 1.41 to 1.96; 55.2, 35.7 to 74.7) had been considerably excessive through the early part solely.

Within the 5-11 years subgroup (supplementary tables S4b and S4h), streptococcal tonsillitis was considerably increased throughout early and late phases (early: 1.25 (1.15 to 1.36) and threat distinction 50.7 (17.9 to 83.5); late: 1.12 (1.05 to 1.21) and 50.0 (−1.5 to 101.5), respectively), whereas threat of conjunctivitis was considerably increased within the early part (hazard ratio 1.24, 1.07 to 1.43; threat distinction 35.7, 9.1 to 62.3) and sore throat through the late part (1.54, 1.20 to 1.97; 29.7, 10.5 to 48.9).

Within the youngest 0-4 years age group (supplementary tables S4a and S4g), we noticed elevated threat for conjunctivitis (hazard ratio 1.18, 1.08 to 1.29; threat distinction 147.3, 51.3 to 243.3) and dyspnoea (1.22, 1.11 to 1.35; 121.9, 47.8 to 196.0) solely through the early part.

General, dyspnoea was essentially the most ample consequence, showing in 5 of the six age teams however remaining persistent all through the primary 12 months after an infection within the 19-40, 41-60, and >60 years age teams. Weak point appeared in 4 of the six age teams and remained persistent within the late part solely within the 19-40 and 41-60 age teams. We measured age associated heterogeneity within the affiliation with an infection by interplay phrases (supplementary tables S4m-n) and located it to be important for dyspnoea (Q<0.001) and hair loss (Q=0.003) and marginally important for weak point (Q=0.1).

We additional explored whether or not lengthy covid medical sequelae differed between unvaccinated female and male sufferers with a constructive SARS-CoV-2 PCR check (fig 6; supplementary tables S5a-c). For many well being outcomes measured, female and male sufferers introduced comparable hazard ratios, with one exception: within the early interval, girls confirmed considerably increased threat for hair loss (hazard ratio 2.09 (1.86 to 2.35) in girls and 0.97 (0.80 to 1.17) in males). Curiously, whereas hazard ratios for weak point and dyspnoea through the early interval had been comparable between female and male sufferers (Q values of 0.65 and 0.22, respectively), the danger distinction for feminine sufferers was increased, indicating that they reported these signs extra usually than male sufferers did after an infection (supplementary tables S5d-e). Impact modification by intercourse was important just for hair loss, within the early interval (Q for interplay <0.001).

Fig 6
Fig 6

Danger of serious reported outcomes in female and male sufferers. Hazard ratios and threat variations (with 95% confidence intervals) for all reported well being situations (supplementary tables 5b and5c) had been evaluated throughout early and late durations

Comparability of long run well being outcomes between SARS-CoV-2 variants

Throughout the research interval, three SARS-CoV-2 variants had been prevalent in Israel: wild-type SARS-CoV-2 (March to November 2020), alpha variant (January to April 2021), and delta variant (July to October 2021). We sought to evaluate the lengthy covid well being outcomes in SARS-CoV-2 constructive sufferers contaminated by the completely different variants (supplementary determine S1).

We in contrast the lengthy covid outcomes that had been considerably completely different in the whole unvaccinated cohort between matched sub-cohorts contaminated by the wild-type virus and the alpha variant (supplementary determine S3; supplementary tables S6a-c). We calculated the hazard ratios individually for every variant, measuring the lingering outcomes within the early and late durations after an infection. General, the medical manifestation of lengthy covid was related between sufferers contaminated by the wild-type and alpha variants, overlapping in each time durations. We in contrast the calculated threat of the long run outcomes in each variants and located no statistically important distinction between the wild-type virus and the alpha variant. Hazard ratios for anosmia and dysgeusia, focus and reminiscence impairment, dyspnoea, and weak point remained persistently increased by means of the 12 months after an infection for each wild-type and alpha strains.

Subsequent, we evaluated whether or not the lengthy covid medical sequelae of the delta variant differed from these of the wild-type pressure and alpha variant by analysing persistent signs 30-90 days after an infection (supplementary determine S4; supplementary tables S7a-b). Contemplating our earlier statement that infections with wild-type and alpha variants confirmed related lengthy covid medical sequelae, we mixed them for this particular evaluation and in contrast them with the danger of outcomes after an infection with the delta variant. We noticed no important distinction within the hazard ratios for the measured outcomes between the wild-type/alpha and the delta variants.

Affiliation between SARS-CoV-2 vaccination and lengthy covid well being outcomes amongst sufferers with gentle illness

Throughout the research interval, a SARS-CoV-2 vaccine was developed, which resulted in a nationwide vaccination marketing campaign in Israel. The aim of this evaluation was to evaluate whether or not the post-covid medical sequelae differed between sufferers who weren’t vaccinated and people contaminated after vaccination. This evaluation included 14 090 individuals older than 12 years with a median age of 35 years (supplementary desk S8a). We in contrast vaccinated sufferers with breakthrough an infection (outlined as a constructive PCR check ≥14 days after the second vaccine dose) with unvaccinated sufferers who examined constructive for SARS-COV-2 (fig 7; supplementary desk S8b). Our evaluation confirmed that vaccinated individuals who turned contaminated and had gentle illness had been at a considerably decrease threat of extended dyspnoea than their unvaccinated controls (hazard ratio 1.58, 1.18 to 2.12). The danger for all the opposite long run well being outcomes was comparable between the teams (supplementary desk S8b). Further evaluation excluded sufferers who had been vaccinated greater than three months earlier than testing constructive for SARS-CoV-2 to ignore the vaccine’s waning immunity. Outcomes confirmed an analogous threat for the outcomes between the 2 vaccine populations whatever the time of vaccination (supplementary tables S9a-b).

Fig 7
Fig 7

Hazard ratios (with 95% confidence intervals) for lengthy covid well being outcomes 30-90 days after an infection for unvaccinated versus vaccinated sufferers. Well being outcomes that had been considerably associated to SARS-CoV-2 an infection had been assessed in vaccinated and unvaccinated sufferers (supplementary tables 8a-b)


This research examined the long run medical outcomes of SARS-CoV-2 an infection in individuals with gentle illness, evaluating digital well being information knowledge from the second largest well being fund is Israel. We analysed retrospective knowledge beginning in March 2020, figuring out individuals with a constructive PCR check and no document of covid-19 associated hospital admission within the following month. The quantitative method we used to decipher the actual world lengthy covid manifestation included following the sequelae of SARS-CoV-2 constructive sufferers for a 12 months after an infection, dividing it into early and the late durations, and assessing the well being outcomes reported within the digital well being document throughout these durations. Our evaluation confirmed an elevated threat for a number of well being outcomes after gentle covid-19 that was extra outstanding through the first six months after an infection and decreased thereafter. Information confirmed that the danger diversified between completely different age teams and barely differed between female and male sufferers and with vaccination standing. These findings may present a clearer image to clinicians and sufferers as to the long run presence and presentation of covid-19, lowering uncertainty and enhancing care.

Comparability with different research

Because the pandemic superior, it turned clear that almost all contaminated individuals would have gentle illness; nevertheless, studies describing long run signs after the acute part raised main considerations. Reviews of post-covid signs, new diagnoses of continual sicknesses, and early problems have been documented, reviewed, and largely adopted for as much as seven months after an infection.8914474849 Our evaluation confirmed that of all of the beforehand described signs and well being outcomes, the danger of 13 outcomes was considerably increased in sufferers testing constructive for SARS-CoV-2 in contrast with destructive controls. Following these outcomes within the late interval, as much as a 12 months post-infection, we confirmed that the danger for a lot of of them decreased and was akin to that in individuals who weren’t contaminated. Anosmia and dysgeusia, focus and reminiscence impairment, dyspnoea, weak point, streptococcal tonsillitis, and dizziness had been nonetheless reported extra continuously in contaminated sufferers a 12 months after an infection, indicating lengthy lasting signs. Earlier research in sufferers with gentle illness have been small in magnitude and adopted sufferers for durations shorter than one 12 months; nevertheless, even on a small scale, the presence of anosmia and dysgeusia, focus and reminiscence impairment, dyspnoea, and weak point has been repeatedly evident.8947 Reviews claimed that environment friendly covid-19 containment methods considerably decreased the prevalence of respiratory tract infections and transmission of different pathogens,5051 however we measured elevated threat for streptococcal tonsillitis as much as a 12 months after SARS-CoV-2 an infection. This will likely point out an elevated sensitivity for this bacterial an infection after covid-19. In kids, SARS-CoV-2 an infection was additionally related to a better incidence of conjunctivitis. This will likely not essentially be a direct hyperlink, however might moderately mediated by decreased immunity resulting in elevated susceptibility to different viruses comparable to adenovirus, which, in flip, set off conjunctivitis. Additional investigation is required to find out whether or not these elevated dangers are restricted to streptococcal tonsillitis and conjunctivitis or mirror immunological well being outcomes inherent to covid-19 typically. We word that decreased social distancing amongst contaminated sufferers might confound the associations between SARS-CoV-2 an infection and later incidence of infectious illnesses comparable to conjunctivitis and streptococcal an infection.

Findings in context

Our evaluation assessed a really massive number of signs reported through the lengthy covid interval and demanded cautious issues to stop biases and potential artefacts within the evaluation. One necessary statement we made was that sufferers with covid-19 had extra blood checks due to their sickness, and this might result in a false important affiliation in situations comparable to fatty liver, which is extremely prevalent but asymptomatic and normally found by liver enzyme abnormalities in blood checks.5253 A second potential bias we noticed was within the studies of lymphadenopathy, which was reported to be a facet impact of the BNT162b2 mRNA covid-19 vaccine.27 We measured a decrease vaccination charge within the SARS-CoV-2 constructive sufferers (15%; 31 063/214 046) than within the destructive controls (29%; 62 558/214 046) after testing. Subsequently, the decrease threat for lymphadenopathy measured for SARS-CoV-2 constructive sufferers could also be a consequence of much less lymphadenopathy on this inhabitants brought on by the decrease vaccination charge.

General, our observations present largely gentle long run morbidity that’s related to SARS-CoV-2 an infection. The organs most affected by covid-19 are the lungs, presenting respiratory sickness of various severity ranges, broadly described in sufferers admitted to hospital and likewise evident in sufferers with gentle illness.7954 Because the illness transfects the lungs, it creates medical manifestations that embody viral pneumonia, dyspnoea, and chest discomfort. Dyspnoea emerged as essentially the most continuously reported respiratory symptom in sufferers with gentle covid-19, lasting a 12 months from prognosis and leading to elevated numbers of prescriptions for associated medicine. However, the danger of receiving a prescription for a pulmonary prognosis was unbiased of SARS-CoV-2 an infection, indicating that the pulmonary outcomes following gentle covid-19 should not extreme and don’t want elevated drug remedy.

As illness severity, hospital admission, and dying are depending on age,55 we assessed the completely different lengthy covid well being outcomes in age subgroups within the gentle illness setting. The very best variety of well being outcomes proven to be persistent six months after covid had been reported within the 41-60 years subgroup, with sufferers within the different age subgroups having fewer well being outcomes reported. The danger for 5 outcomes within the 41-60 years subgroup remained considerably increased all year long after an infection, however solely dyspnoea remained considerably increased within the late interval within the oldest subpopulation of >60 years. This would possibly recommend that covid-19 wouldn’t be thought of gentle in older individuals if a number of signs persevered, leading to sufferers being admitted to hospital and excluded from this research. Youngsters had an elevated threat of a small variety of outcomes through the early part, which then returned to baseline within the late part.

The sample that emerged through the pandemic has been of spikes of covid-19 instances adopted by decline, known as covid waves. As SARS-CoV-2 unfold across the globe, it mutated and completely different viral variants had been recognized and have become dominant in every covid wave. Reviews have proven that variants introduced variable transmission patterns, virulence, severity of illness signs, and compromised vaccine safety.56575859 On this research, we analysed the heterogeneity between the dominating SARS-CoV-2 variants and long run well being outcomes after gentle an infection. Comparability of the wild-type pressure and the alpha variant as much as a 12 months after an infection confirmed no important variations in well being outcomes, and variants confirmed similarity in each early and late time durations. Equally, we noticed no important variations in well being outcomes when evaluating wild-type/alpha and delta strains for 3 months after an infection. These outcomes recommend that the wild-type, alpha, and delta variants resulted in related long run covid-19 sequelae, and extra evaluation of long run outcomes of the delta and the omicron variants might make clear whether or not lengthy covid sequelae differ by completely different SARS-CoV-2 variants. The comparability of variants on this research was centered on relative phrases. Though the affiliation between an infection and outcomes was related throughout variants by way of relative threat, absolutely the threat distinction will depend on baseline threat and will thus differ between variants.

Because the pandemic advanced, vaccines had been developed and international vaccination campaigns confirmed that they may shield individuals from critical sickness and forestall dying. In Israel, the BNT162b2 SARS-CoV-2 mRNA vaccine was evaluated in a nationwide vaccination marketing campaign and successfully decreased symptomatic covid-19, hospital admissions, extreme illness, and dying.3031 Latest research have additionally proven that vaccination leads to discount within the threat of the post-acute sequelae of covid-19.164460 On this research, we assessed the affiliation between vaccination standing and long run well being outcomes in sufferers with breakthrough infections and gentle illness course. Our research didn’t measure safety from acquisition of an infection or from extreme sickness, hospital admission, and dying, so it doesn’t contradict any of those confirmed advantages. Our findings recommend that gentle covid-19 in vaccinated individuals was considerably related to decreased threat for dyspnoea in contrast with unvaccinated sufferers as much as three months after an infection. That is in accordance with studies displaying that vaccination earlier than SARS-CoV-2 breakthrough an infection partially decreased the danger of post-acute sequalae.44

Strengths and limitations of research

This research had a number of strengths. We used longitudinal medical reporting on a nationwide scale, based mostly on digital well being information from a public well being fund that features illustration of the heterogeneous Israeli inhabitants with its demographic and socioeconomic subpopulations, minimising choice bias. This range permits the findings to be generalisable to related western populations worldwide. The longitudinal and detailed digital well being information allowed us to distinguish between well being outcomes and new diagnoses that appeared after a covid-19 an infection and exclude people who had been beforehand documented within the sufferers’ medical historical past. Moreover, as all knowledge on drug prescriptions, hospital admissions, PCR checks, and vaccinations had been obtainable to us, we had been assured as to the validity and date of the covid-19 prognosis, and we may exclude sufferers admitted to hospital with a extra critical sickness; the excessive testing frequency in Israel enabled us to construct a dependable uninfected management group with these individuals who examined solely destructive. Our research included numerous younger contaminated sufferers with gentle illness, together with 118 308 contaminated below the age of 18; the general median age was 25 years. This allowed for bigger statistical energy for these age teams, which comprise most sufferers with gentle illness and but had been much less represented in earlier publications.9 We particularly used digital well being information and never questionnaires, establishing clinically important long run sequelae reported by medical professionals after interview and medical analysis of sufferers. Our matching strategies with controls with a destructive PCR check consequence allowed us to neutralise confounders (age, intercourse, date of an infection, and vaccination standing) whereas verifying contact with healthcare companies concerning covid-19 and different situations. The big dataset allowed us to do an in depth longitudinal evaluation together with greater than 70 signs, acute diagnoses, infectious illnesses, and continual situations that had been adopted for a 12 months after verified SARS-CoV-2 an infection, representing one of many longest follow-up research in sufferers with gentle covid-19 so far.

The research additionally had a number of limitations. We measured outcomes that had been reported in structured medical coding within the digital well being document and had no entry to diagnoses and outcomes reported in free textual content format, so these knowledge won’t fully mirror diagnoses and outcomes reported. Though we can’t rule out diagnostic errors of situations with related well being outcomes, we consider that they’re equally probably in each teams—that’s, misclassification of outcomes is non-differential. Owing to using secondary knowledge, the incidence of minor diagnoses could also be underestimated. Nonetheless, main signs probably want medical recommendation or remedy and are much less more likely to stay unreported and unrecorded. As well as, detection bias is more likely to be non-differential between sufferers contaminated and never contaminated with SARS-COV-2. Affected person reported outcomes comparable to weak point, cognitive impairment, anosmia, and dysgeusia are much less goal than medical diagnoses by physicians and won’t be uniform and correct. We can’t rule out potential behavioural and environmental variations between contaminated and uninfected individuals, which could trigger overestimation of the incidence among the many contaminated inhabitants. Particularly, some well being searching for bias might exist, wherein sufferers with covid-19 could also be extra energetic in sustaining their well being, together with extra frequent healthcare service use, leading to increased reporting and elevated screening for potential covid-19 associated outcomes in these sufferers. Contaminated sufferers could also be extra socially energetic or much less cautious after their an infection and thus doubtlessly uncovered to a better threat of different infectious illness (comparable to group A Streptococcus and conjunctivitis). Contaminated sufferers are exempt from isolation after their an infection, making them doubtlessly extra susceptible to additional infectious illnesses than uninfected individuals. However, this bias ought to lower with time and have an effect on the long run evaluation much less. We additionally can’t exclude further confounders that have an effect on long run outcomes of SARS-CoV-2 an infection that had been unavailable to us on this research. Moreover, a few of these outcomes (comparable to paediatric multisystem inflammatory syndrome) had been reported at low frequency and due to this fact would possibly want bigger populations. One other weak point could possibly be under-reporting of signs within the later durations, when sufferers had reported the outcomes near prognosis of covid-19 and didn’t proceed reporting them as time from prognosis superior. This research additionally is perhaps biased in the direction of together with vaccinated sufferers with symptomatic covid-19 within the evaluation, as vaccinated sufferers weren’t obliged to get examined and people with no signs might need not been examined. As well as, the research was restricted to individuals who had PCR checks. Nonetheless, the huge accessibility of PCR checks provided to all Israeli residents freed from cost with no want for referral minimises the priority about non-generalisability. Lastly, the follow-up interval for the delta variant was restricted to 90 days and desires longer analysis.


This research examined the associations of gentle covid-19 following SARS-CoV-2 an infection and long run well being outcomes. Though the lengthy covid phenomenon has been feared and mentioned for the reason that starting of the pandemic, we noticed that almost all well being outcomes arising after a light illness course remained for a number of months and returned to regular inside the first 12 months. This nationwide dataset of sufferers with gentle covid-19 means that gentle illness doesn’t result in critical or continual long run morbidity within the overwhelming majority of sufferers and provides a small steady burden on healthcare suppliers. Importantly, the danger for lingering dyspnoea was decreased in vaccinated sufferers with breakthrough an infection in contrast with unvaccinated individuals, whereas dangers of all different outcomes had been comparable.

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