National sero survey: Districts deemed ‘zero caseload’ in May had 8.5 lakh cases

As many as 15 districts having zero-case during the time were studied.

COVID-19 in India update: As health experts in India continue to look for a pattern in Coronavirus cases in the country, a national sero surveillance study has pointed out that around 8.56 lakh COVID-19 cases were actually present in May in 233 districts that were thought to have zero caseload. A report by The Indian Express, citing the national sero surveillance data, mentioned that at a time when it seemed the COVID-19 transmission in some districts was quite less, the districts may have accounted for a significant number of cases. Two months after the Coronavirus pandemic broke out in the country, these districts may have had around 13 per cent of the total cases in the country.

It is to note that the study published in the Indian Journal of Medical Research highlighted that as many as 64.68 lakh infections have been estimated in the country during May; of which 8.56 lakh cases were present in districts deemed as zero-caseload; 18.17 lakh cases in areas with low-prevalence of COVID-19; 15.18 lakh cases in districts with medium-prevalence; and 22.76 lakh cases in areas with a high transmission rate. As many as 15 districts having zero-case during the time were studied.

According to researchers, the data revealed that the initial surveillance, as well as contact tracing, was poor in districts with low caseload, which later resulted in increased transmission of the deadly virus. Apart from this, in the earlier phase of the outbreak, the testing facilities were also not great and many cases, therefore, went undetected. In districts with zero caseloads, 6,014 adults were studied and it was found that 19.7 per cent of them were working under occupations with high exposure to the virus. Among these 53 per cent had asked for medical care for respiratory symptoms. Citing researchers the report said that the findings of the study indicate the “need to strengthen surveillance and augment the testing of suspected cases in these areas,”

Meanwhile in India, around 4.6 lakh cases have been reported so far, according to the official figures available from the Ministry of Health and Family Welfare. These are the cases that have been tested positive via RT-PCR tests. Sero-survey, on the other hand, notes the number of people having antibodies against Coronavirus infection as the infection may have gone unnoticed (also known as asymptomatic cases).