E-Paper
Respiratory illness study hints at community spread: Experts
Covid-19 update: The study, published in the Indian Journal of Medical Research (IJMR) on Thursday, found that Covid-19 positivity among severe acute respiratory infections (Sari) patients is 1.8% out of 5,911 samples tested between February 15 and April 2.
About one in 50 people hospitalised with acute respiratory infections such as pneumonia are suffering from the coronavirus disease (Covid-19), according to a new study by the Indian Council of Medical Research (ICMR) and the National Centre for Disease Control (NCDC) — findings that some experts said suggested the disease has entered the “community transmission” phase in the country.
Close to 40% of these patients did not have recent travel history or known contact with a Covid-19 case.
The study, published in the Indian Journal of Medical Research (IJMR) on Thursday, found that Covid-19 positivity among severe acute respiratory infections (Sari) patients is 1.8% out of 5,911 samples tested between February 15 and April 2.
Among the 965 Sari samples tested between February 15 and March 19, only two (0.2%) were positive for Covid-19. But when the testing strategy was expanded to include all Sari patients, out of 4,946 samples, 102 (2.1%) were positive for Sars-CoV-2 (the virus that causes Covid-19).
According to the survey, of the 102 Covid-19-positive Sari patients, one reported a recent history of international travel, two reported contacts with a confirmed case, and 40 (39.2%) did not report any history of international travel or contact with a Covid-positive person. The data on exposure history was not available for 59 cases.
“One may not like to call it community transmission but this is in fact community transmission of Covid-19,” said Dr T Jacob John, professor emeritus and former head of virology at the Christian Medical College, Vellore.
“Sari in the absence of Covid-19 is essentially due to influenza A (H1N1 or H3N2) or influenza B (the Victoria strain or Yamagata). These four are essentially the only reasons for Sari. Sometimes Sari patients are also affected by Adenoviruses. The results of the ICMR study indicates that Covid-19 is entering this scene. So now we have about two Sari patients in 100 who are testing positive for the new virus. It’s becoming a much commoner problem than what we had expected earlier. Waiting for this evidence for intervention is not needed,” Dr John added.
Community transmission is the third of the four stages of the spread of an infectious disease. The first is travel history, the second is local transmission, the third is community transmission, and the fourth is epidemic.
India has maintained that the disease is in the second stage, or between stage two and stage three with “limited community transmission” in some clusters.
The median age of Covid-19 positive Sari patients in the study was 54. It found that Covid-19 positivity was higher among men (85 of the 102 Covid-19 positive patients).
Most of the Sari patients tested were from Gujarat (792), followed by Tamil Nadu (577), Maharashtra (553) and Kerala (502). Covid-19 cases among these were detected from 52 districts in 20 states.
“Covid-19 containment activities need to be targeted in districts reporting Covid-19 cases among Sari patients. Intensifying sentinel surveillance for Covid-19 among Sari patients may be an efficient tool to effectively use resources towards containment and mitigation efforts,” the study said.
Another expert said that it was still too early to say this was “community transmission”.
“We can’t just jump to the conclusion that there is community transmission from these findings. These are from the laboratory and we haven’t started testing in the community yet. I think their case history hasn’t been analysed properly yet,” said Dr Shobha Broor, former head of the department of microbiology at the All India Institute of Medical Sciences.
