Asymptomatic transmission Achilles’ heel of Covid-19

New Delhi: Asymptomatic transmission of SARS-CoV-2 appears to be Achilles heel of COVID-19 pandemic, and experts suggest it may have largely contributed towards the recent spike in positive cases in the country.

According to a UK study, the rapid spread of COVID-19 across the United States and the globe, the clear evidence of SARS-CoV-2 transmission from asymptomatic persons, and emphasis should be on broadening testing to include asymptomatic persons in prioritized settings, which include healthcare workers.

Speaking to IANS, Prof. K Srinath Reddy, President of Public Health Foundation of India said, “Lockdown intent and effect was to slow down the transmission. It does not expel the virus from our country or the planet. There will be more cases- both tested and labelled and untested and asymptomatic. These numbers by themselves should not alarm us.”

He insisted on monitoring some crucial indicators — number of new cases detected daily as a percentage of the number of new tests performed daily and number of influenza like illness detected by symptom based syndromic surveillance.

“Monitoring coronavirus positive cases of serious acute pulmonary infection in hospitals and weekly death count of the positive cases. We can track the speed and slope of the epidemic by these measures while accepting the reality that we must continue physical distancing, hand hygiene and masks for at least a year more”, added Prof. Reddy.

With a surge of 3,390 new cases and 103 new fatalities in the past 24 hours, the total tally of novel coronavirus cases in India stood at 56,342 on Friday. Of the total cases, 37,916 are active while 1,886 people have lost their lives. A total of 16,593 though have recovered as India undergoes the third-phase of the nation-wide lockdown.

Dr. Vikas Maurya, Director and Head – Pulmonology at Fortis Hospital, said : “Cases are mounting and the possible reason could be increase number of people being tested now, or pending reports are coming positive now or could be due to asymptomatic transmission now affecting other people or could be due to relaxation given in lockdown.”

He insisted that this is worrisome and it looks that peak is yet to come in India.

“Presently cases were increasing at a linear rate but with spurts now for the last couple of days. It looks like lockdown needs to be extended further along with other social behaviour measures…. Very difficult to pinpoint any one point and we may well be peaking in near future”, added Maurya.

In the last week, China began to release data on asymptomatic coronavirus patients, which experts say will help other countries to attune their response to the pandemic and also provide crucial information on the spread of the virus.

A study out of Singapore released earlier this week, estimated the transmission rate by healthy-looking individuals was major, and it found that around 10 per cent of new infections could be from asymptomatic patients.