Effectiveness of COVID-19 vaccine (Covaxin) against breakthrough SARS-CoV-2 infection in India.

India approved COVID-19 vaccine called Covaxin, developed by the Indian Council of Medical Research and Bharat Biotech Ltd. The primary objective of the study was to estimate the effectiveness of Covaxin in preventing breakthrough SARS-CoV-2 infection in healthcare workers (HCWs). A test-negative matched case-control study was conducted among HCWs of tertiary care hospital in Eastern India. Any HCW who tested positive for COVID-19 using RT-PCR during April and May 2021 was taken as the case. The HCWs who tested negative for COVID-19 by RT-PCR were considered as controls after matching with the date of testing and profession of the cases. Vaccination data were collected from the institution's vaccine database and recall. In case of discrepancy, it was confirmed from the CoWIN portal (cowin.gov.in). The sample size was 670 participants (335 pairs). Conditional logistic regression models were used to calculate the adjusted odds ratio for breakthrough SARS-CoV-2 infection. Vaccine effectiveness was calculated using the following formula: VE = (1-aOR) × 100%. Sensitivity analysis was done for effectiveness of Covaxin, excluding Covishield vaccination. The mean age of participants was 29.1 years (SD = 7.1), and the majority were males (55.2%). Among the study participants, 60% were completely vaccinated, 18.51% were partially vaccinated, and 21.49% were unvaccinated. After adjusting for age, gender, type of household and past history of COVID-19 disease in conditional logistic models, the vaccine effectiveness was 22% (aOR 0.78, 95% CI: 0.52-1.17; p = .233). Sensitivity analysis with Covaxin showed an effectiveness of 29% (aOR 0.71, 95% CI: 0.47-1.08; p = .114) for preventing breakthrough SARS-CoV-2 infection.

Adverse events following immunization of COVID-19 (Covaxin) vaccine at a tertiary care center of India.

The study aimed to assess the adverse events following COVID-19 vaccine (Covaxin) immunization at a tertiary care institution and also assess the predictors of the adverse events following immunization (AEFI). The prospective observational study was conducted in a tertiary care institute among the Covaxin beneficiaries between June 28 and September 6, 2021. A total of 1826 participants were assessed for any local or systemic adverse events after seven days of vaccination. A telephonic interview was conducted, and the beneficiaries were assessed according to the adverse event grading. A total of 1826 participants were assessed for AEFI, and 544 (29.8%) reported at least one of the AEFI. No severe adverse events were reported, and about 1.6% had moderate AEFI. Pain at the injection site (14.6%), fever (9.7%), and myalgia (5.9%) were the common adverse events reported by the participants. AEFI incidence was higher in the first dose (38.1%) when compared to the second dose (26.4%), and this finding was significant with a p < 0.001. The major factors associated with AEFI were female sex, history of an allergic reaction, presence of comorbidities, acute infection in the past 3 months, and intake of chronic medications. Precaution needs to be taken while vaccinating individuals having allergies, comorbidities, acute infection in the last 3 months, and individuals on chronic medication.

Masks in COVID-19 pandemic: Are we doing it right?

The coronavirus (COVID-19) pandemic has caused the world to undergo an unprecedented change in a short period. Personal protective equipment such as the face mask or face cover has become a daily necessity. Moreover, since some states and countries have made the use of face covers or face masks compulsory, one cannot ignore or afford to have a wrong or incomplete awareness about face masks. Current information suggests that the two main routes of transmission of the COVID-19 virus are respiratory droplets and contact. This article aims to review the existing information and highlight the need for the use of face masks or face covers to combat the COVID-19 pandemic and promote and provide necessary recommendations. Many countries have implemented or recommended mask wearing in the community, but recommendation for rational use of masks is being issued, as the crisis and shortage for masks are universally existing. The use of different types of masks has been assigned according to the risk of exposure and should be therefore judiciously used. As this is a novel disease, the guidelines are changing every day and one needs to be updated with correct information so that one can protect themselves and their families from this extreme level of the crisis faced by the world now. The use of face covers or masks should not be discouraged as there has been substantial evidence that its use can help reduce the spread of infection. "Mass masking" along with hand hygiene and social distancing are the only effective recommended measures to prevent the spread of the disease.