One in 4 Delhi residents is Covid affected; large population still vulnerable: Govt survey

Aditi Tandon

Tribune News Service 

New Delhi, July 21

Only one in four Delhi residents have contracted COVID-19 in six months of the outbreak of the virus.

A National Centre for Disease Control surveillance of the Delhi population has shown that 23.48 per cent of the people have developed antibodies to the disease showing their past history of COVID-19 infection.

The NCDC conducted sero surveillance between June 27 and July 10. Blood samples were collected from 21,387 people and the ICMR developed ELISA tests were also done to detect antibodies for the disease.

Antibodies were found in only 23.48 per cent people.

“Nearly six months into the epidemic, only 23.48 per cent of the people are affected in Delhi, which has several pockets of dense population. This can be attributed to the proactive efforts taken by the government to prevent the spread of the infection such as prompt lockdown, effective containment and surveillance measures, including contact tracing and tracking, as well as citizen’s compliance COVID Appropriate Behaviours,” Health Ministry said today.

A downside of the survey, however, is that a large population in the national capital is still susceptible to the disease since only a very small proportion have been infected.

“A significant proportion of the population is still vulnerable. Therefore, containment measures need to continue with the same rigour. Non-pharmacological interventions such as physical distancing, use of face masks and covers, hand hygiene, cough etiquette and avoidance of crowded places must be followed strictly,” the ministry said.

Survey teams were formed for all 11 districts of Delhi. Blood samples were collected from selected individuals after taking written informed consent and then their sera were tested for IgG antibodies and infection using COVID KAVACH ELISA approved by the Indian Council for Medical Research.

Delhi’s survey is one of the largest seroprevalence studies conducted in the country using the ELISA testing. A national survey earlier conducted had covered around 20,000 samples until April and found less than one per cent Indian population had antibodies to the COVID causing virus.

A large susceptible population is a major concern going forward.

Epidemiologists say as long as tenges a large susceptible pool the virus will spread and physical distancing measures will remain key protections.

Antibody testing repeatedly was done over time.

Sero surveillance generates important evidence for assessing the spread of the pandemic from time to time.

The results of the seroprevalence study show that on an average, across Delhi, the prevalence of IgG antibodies is 23.48 per cent.