The city’s COVID-19 case count has been increasing day after day. This is partly due to its population density — a factor that has made the already challenging task of contact tracing all the more difficult.
Tracing contacts of patients was taking more time in Chennai than in other districts of Tamil Nadu, a health official said. Carrying out the exercise in the State capital was arduous, he added.
“For instance, we are given the address of a person. On reaching the place, we come to know that he does not live there. We then find out that he resides just behind that particular house,” he explained.
As expected, the number of contacts of each patient was relatively higher in Chennai due to urban density, another official said. “Some persons provide incomplete addresses and wrong mobile numbers. This causes delay in the process. It is their responsibility to provide a complete address with the right phone number,” he added.
In fact, the metropolitan city has another problem — many residents do not know their neighbours. “There are people who do not know the names of their neighbours. Such details are important for epidemiological investigation,” the official said.
An official of the Chennai Corporation said that extensive efforts were being made in terms of contact tracing in the city. The exercise covered both close contacts, i.e., family members, and extended contacts. “Finding the extended contacts is more like an art,” he said.
“It is a harder task here. There are places where the population is densely packed. There are narrow streets, or buildings that have 10 families, or slum areas where people are tightly packed. Narrowly defining extended contacts might be meaningless. So we comb the entire area,” he said.
Not an easy task
For instance, in the north region of Chennai Corporation, there were 111 index cases, for which a total of 3,081 contacts — 640 direct contacts and 2,441 extended contacts — were traced and tested. “For every positive case, we have 30 more persons who are traced and tested,” an official said. By and large, people are cooperating, said officials. “We haven’t had instances where people had not cooperated with us for the contact-tracing process. But human memory is fallible. The real challenge is that we come to know that somebody is infected only when they test positive, but they may have been infected 15 days ago,” the official said.
“Field-level health inspectors make discrete enquiries, and enable patients to recall from memory the places they visited and the persons they met,” the official added.
