Every time a person tests positive for coronavirus disease (COVID-19), a process for tracing his/her contacts is activated. Exclusive teams at the State and district-level trace the path that the patient took, tracking persons with whom he/she came into contact, before testing positive.
Till now, officials have tracked approximately 7,000 close contacts of patients who have tested positive for COVID-19, in Tamil Nadu. There are many others -- primarily low risk contacts -- who have also been tracked down.
Contact tracing is not an easy job, but is a crucial exercise. Tracking contacts of patients is essential -- to identify those who were exposed to the disease and manage them, restrict their movement and prevent further transmission, officials said.
“It is a meticulously done exercise otherwise we would not have been able to track and follow-up so many contacts,” a health official said. In Tamil Nadu, some of the major departments involved in contact tracing are the Directorate of Public Health, Home Department, the police and local bodies.
With teams at the State and district-level, they rewind the movement of each patient -- places visited, mode of transport used and persons he/she came in contact with. Officials said they ask the individual or their close family member for details on travel history -- whether they travelled by flight or train, their recent places of visits including clinics and hospitals. The appropriate authorities -- airports, railways or app-based ride-hailing services are contacted directly for information.
Consider this: if patient ‘A’ had tested positive (prior to the lockdown), he/she could have travelled by public transport at a particular time, or taken an autorickshaw from a stand or on the move, or an app-based ride-hailing service or visited a market or the beach. If the person had travelled by train or flight, the details with the exact seat numbers have to be provided by the Southern Railway or Airports Authority of India. The teams gather information of contacts by also collecting CCTV footage from places the patient visited if the surveillance facility is available. They track movement using mobile phone signals, an official said.
“The critical point is when patient ‘A’ started to develop symptoms. We should take this into consideration -- there is the possibility of a patient transmitting the disease in the pre-symptomatic period too,” an official said.
Sometimes, the close contacts are not ready to get identified and mobile phones may be switched off. “Routinely, around 200 to 300 persons are traced for a patient. But the crux is not tracking a big number but the right number of persons. Again, this may not be the case for all. Some patients will have a smaller track, they would have gone home from the airport in their personal car, did not visit any place and approached a hospital on developing symptoms. We have had less than 10 contacts for such persons too,” he added.
Officials call for greater cooperation from the public. “Contact tracing is done for the welfare of the people. Initially there was mild resistance but now, people have started to cooperate. District teams have a major role to play as they interact and identify more since they have direct one-to-one conversations,” another official said.
Whoever is in close contact with a confirmed COVID-19 patient or those suspected to have symptoms, should be in strict home quarantine. If they have any symptoms of cough, fever and breathing difficulty, they can contact the local hospital or toll free number for any help -- 104, officials said.
