ICMR study shows Covid-19 reinfection in 4.5% of cases

A study entitled “SARS-CoV-2 Reinfection: Development of Epidemiological Definitions from India” published by Cambridge in the Journal of Epidemiology and Infection investigated with the aim of developing a possible epidemiological case definition of SARSCoV. Was done. -Two reinfections and an assessment of the scale of more than 1,300 individuals in India.

“In conclusion, the epidemiological case definition of SARS CoV-2 reinfection is important for enhanced surveillance. Current studies have contributed to this goal and reinfection in 4.5% of SARS CoV-2 infected individuals in India. We are recording, “the study states. .. Taking into account the available evidence, SARS CoV-2 reinfection in the study was performed by SARS-CoV-2 on two separate occasions, either by molecular testing or by rapid antigen testing at at least 102 intervals. Defined as an individual who was positive. The day when there is one negative molecule test in between.

“The data were only for the eight months from January 22, 2020 to October 7, 2020, so the findings may be of concern. This is the current scenario of an increasing number of new cases. It can be much higher or a little less, so it is very important to take protective action after infection or vaccination, “said ICMR Epidemiology and Infectious Diseases Director, one of the authors of the study. Said Dr. Sami Lampanda. You need a specific infrastructure that is not always available everywhere. The new definition makes it easy to tab tab for reinfection cases in India, “he said.

According to public health experts, the findings came when the country was experiencing a second wave of infection and, despite continued vaccination, than the first wave. It is expected to get worse. Reinfection of covid-19 is rarely reported yet, but immunity should never be assumed and public health measures such as physical distance, hand hygiene, and mask use after recovery from the initial infection event. Must be followed. ..

Reinfection of SARSCoV-2 is still a rare phenomenon, but researchers say that an epidemiological definition of reinfection is needed to establish a surveillance system. The findings may be a source of government concern, as cumulative vaccine doses are approaching 70 million under India’s national vaccination drive. The vaccination drive was deployed on January 16, 2021 and began vaccination of healthcare workers (HCW) and frontline workers (FLW) on February 2, 2021. For people over the age of 60 with certain comorbidities.

Starting Thursday, the government also began vaccination of all persons over the age of 45, regardless of comorbidities. However, an emergency committee of the World Health Organization (WHO) Commission states that the effects of vaccines on reducing infections are not yet known. Reinfection can interfere with the fight against the pandemic.

“There are many uncertainties in the immunity caused by natural infections. No vaccine is 100% effective, except for smallpox vaccine. Currently available vaccines are symptomatic confirmed in the Covid-19 laboratory. It can reduce the number of cases of smallpox and the number of severe cases that require hospitalization and death. However, asymptomatic infections can occur, “said a scientist and former ICMR epidemic. And Lalit Kant, who is responsible for the infectious disease, said.

“These vaccines were tested against circulating strains of SARSCoV-2 when clinical trials were conducted. Another subspecies is currently being distributed in different parts of the world. It can infect the species. In theory, it could be re-infected after corona vaccination with the same or different variants. “

Currently, there is no consensus on a practical definition of reinfection based solely on epidemiological characteristics. The only confirmation is a resource-intensive method such as whole-genome sequencing. The US Centers for Disease Control and Prevention (CDC) considered 90 days between two positive SARS-CoV-2 RNAs and genomic evidence of reinfection as a criterion for understanding the phenomenon of reinfection.

Both the CDC and the European CDC have proposed using genomic evidence to confirm reinfection, but epidemiological work definitions assess the magnitude of reinfection in most population and resource-constrained environments. It is more practical and useful to do.

In this archive-based telephone survey, 58 of 1300 (4.5%) met the suggestive definition of ICMR. 38 individuals, who account for 31.6% of cases, may come into contact with healthcare professionals. The majority of participants were asymptomatic and showed higher Ct values ​​in the first episode. Ct refers to the number of cycles required to amplify viral RNA to reach detectable levels. High Ct values ​​may be an indicator of viral load.

The authors further suggested that health care worker samples be stored for genomic analysis to study suspicious covid-19 reinfection. It takes place in a resource-constrained environment, especially because of the potential for high-risk occupational exposure and the high likelihood of encountering such events.