Migrant workers from Punjab talk to officials outside the Bengaluru district collector’s office to travel home, on Thursday. (PTI)

A GROWING number of people turning up in hospitals with Severe Acute Respiratory Infection (SARI) and then testing positive for the coronavirus, with seemingly no history of travel or contact with COVID-19 patients, has become a source of concern for Health officials in Karnataka.

According to daily state data, 36 persons reported in hospitals with SARI and later tested positive for COVID-19 over the last month — making up as much as seven per cent of the 525 cases reported in the state, including 10 of the 21 deaths.

This has led to the closure of as many as five hospitals in the state, fear among non-COVID-designated hospitals to attend to SARI cases, and the use of PPE kits by health workers attending to SARI cases in COVID hospitals.

After the ICMR expanded testing to SARI patients on March 20, a state-level technical expert committee stated that “Severe Acute Respiratory Illness (SARI) cases and Influenza Like Illnesses (ILI), which have got similar symptoms of COVID-l9, should be screened at the initial stages of symptoms so that morbidity and mortality due to COVID-19 can be arrested in the community’’.

As of April 29, there were six cases of ILI (1 per cent) with positive results apart from the 36 SARI cases in Karnataka.

Among the recent such cases include a 65-year-old man who died in the SARI ward of the Rajiv Gandhi Institute of Chest Diseases on April 13 and a 54-year-old migrant worker from Bihar who tested positive on April 22.

As many as 30 persons linked to the worker have tested positive and one private hospital, where he was initially seen by doctors, has been sealed along with the Hongasandra locality in Bengaluru, where he lived. As many as four other hospitals around Karnataka have been sealed after SARI cases turned COVID-19 positive.

“The SARI cases are proving to be very tricky. A lot of hospitals are turning away patients to designated COVID-19 hospitals. We created a SARI ward on March 27 apprehending such a situation. Our health workers are using PPE kits in the SARI ward as a precaution to prevent infection,’’ said Dr C Nagaraja, director of the Rajiv Gandhi Institute of Chest Diseases in Bengaluru, one of the designated COVID-19 hospitals.

“The number of SARI cases with no travel history or reported contacts with positive persons suggests that there is some level of community transmission occurring in the state,’’ said a senior doctor in the state health and family welfare department.

But others dealing directly with SARI cases suggest that a lack of in-depth investigation of contacts of persons creates an impression of community spread. “There is no community transmission happening. The persons who come with SARI to the hospital and test positive for COVID-19 have had contacts with an infected person but they fail to recall the contact or report it when brought for admission,’’ said Dr Nagaraja.

The numbers of SARI cases returning positive results in Karnataka is in excess of what has been found nationally by the ICMR COVID Group and researchers at the Council’s National Institute of Epidemiology (NIE) in a study published on April 28.

“A total of 104 (1.8%) of 5,911 SARI patients tested were positive for COVID-19. These cases were reported from 52 districts in 20 States/Union Territories. The COVID-19 positivity was higher among males and patients aged above 50 years. In all, 40 (39.2%) COVID-19 cases did not report any history of contact with a known case or international travel,’’ the study by Dr Manoj Murhekar, the NIE director and others reported in findings published Tuesday in the Indian Journal of Medical Research.

The study used SARI and COVID-19 case data from February 15 to April 2 for the analysis covering a period when SARI cases were not being tested (February 15 to March 20) and the period when they were being tested.

“Among the 965 SARI patient samples that were tested retrospectively between February 15-29, 2020, and March 19, 2020, two (0.2%) were positive for COVID-19. When the COVID testing strategy was expanded to include all SARI patients, a total of 4,946 samples yielded 102 (2.1%) cases. The positivity increased from zero during the initial weeks to 2.6 per cent in the 14th week,” the study reported.

The study showed a positivity rate of 1.6 per cent for Gujarat, 0.9 per cent for Tamil Nadu, 3.8 per cent for Maharashtra and 0.2 per cent for Kerala — the states from where the majority of samples were taken. It suggested that “containment activities need to be targeted in districts reporting COVID-19 cases among SARI patients”.