Case reports of carditis after the COVID-19 vaccination have accrued globally. Several studies have also reported similar findings, but analytic research on the speculative association is limited.
Researchers from the University of Hong Kong studied 160 case-patients (with carditis) and 1,533 control patients (without carditis) to examine the potential risk of carditis associated with vaccination with BNT162b2 or CoronaVac.
Ten control patients were matched with case-patients based on age, sex, and date of hospital admission. After conducting analyses, the authors found 20 cases of carditis associated with BNT162b2 and 7 associated with CoronaVac vaccination.
Patients who received BNT162b2 were 3 times more likely to experience carditis than unvaccinated patients. On the other hand, patients who received CoronaVac had a similar chance as unvaccinated patients to experience carditis.
Researchers also observed that risk increase associated with BNT162b2 was predominant in males and was more likely to be seen after the second dose.
Cumulative incidence of carditis after vaccination was 0.57 per 100,000 doses of BNT162b2 and 0.31 per 100,000 doses of CoronaVac, demonstrating a very low absolute risk of carditis after vaccination.
According to the authors, none of the 20 case-patients with carditis after BNT162b2 vaccination were admitted to the ICU or died within the observation period, compared with 14 of 133 unvaccinated patients admitted to the ICU and 12 deaths.
Based on the evidence, ACP advises against using SARS-CoV-2 antibody tests for the diagnosis of SARS-CoV-2 infection. ACP also advises against using SARS-CoV-2 antibody tests to predict the degree or duration of natural immunity conferred by antibodies against reinfection, including natural immunity against different variants.
Researchers also note that these practice points do not evaluate vaccine-acquired immunity or cellular immunity. Vaccination is currently the best clinical recommendation for preventing infection, reinfection and serious illness from SARS-CoV-2 infection and its variants.
Additionally, a previous practice point concerning the use of antibody tests to estimate community prevalence of SARS-CoV-2 infection has been retired due to limited relevance, as vaccinations have become widely available in the U.S.
In light of these evidence gaps, individuals and communities must continue to use all available tools to help slow and reduce further spread.
Source: Medindia