Are Asymptomatic COVID-19 Patients Silent Super-Spreader Of The Deadly Virus

Over the past one week, India has witnessed a massive surge in COVID-19 cases across the country with cases almost touching the 10,000-mark and set to surpass the number in a few days.

Some states have also reportedly seen a significant spike in cases ever since the lockdown norms were eased.

Amid the rising cases and hospitals facing acute shortage of beds and medical staff, asymptomatic patients remain a matter of concern.

Some people, particularly young and otherwise healthy individuals, who are infected by the coronavirus never develop symptoms or only develop mild symptoms. Others might not develop symptoms until days after they were actually infected -- these are asymptomatic patients.

The World Health Organisation has asserted that coronavirus patients without symptoms aren¡¯t driving the spread of the virus, casting doubt on concerns by some researchers that the disease could be difficult to contain due to asymptomatic infections.

Dr Maria Van Kerkhove, head of WHO¡¯s emerging diseases and zoonoses unit, said at a news briefing in Geneva on Monday that while asymptomatic spread can occur, it¡¯s not the ¡®main driver' of new infections.

Reuters

This is a stark diversion from what the WHO said earlier. The World Health Organisation (WHO) had earlier stated that while asymptomatic spread can occur, it is not usually the only way that the coronavirus disease is being transmitted. Initial evidence from the earliest outbreaks suggested that the SARS-CoV-2 virus could spread by a person showing no symptoms.

While there are instances of asymptomatic patients transmitting the virus to others particularly in nursing homes and in household settings, this may not be the primary cause of infection transmission.

¡°From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual. It¡¯s very rare,¡± Dr Maria Van Kerkhove said, adding that more research and data are needed to ¡®truly answer¡¯ if asymptomatic patients can infect other people.

Making matters worse, a study published on June 3 in the Annals of Internal Medicine hints at the possibility of asymptomatic people becoming possible silent super-spreaders of SARS-CoV-2.

"The likelihood that approximately 40-45 per cent of those infected with SARS-CoV-2 will remain asymptomatic suggests that the virus might have greater potential than previously estimated to spread silently and deeply through human populations," the study states, as quoted by a report in India Today.

The study done by the researchers at the Scripps Research Translational Institute points to the fact that asymptomatic Covid-19 patients can "transmit" the deadly novel coronavirus.

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The scientists reviewed data from 16 different groups or cohorts of Covid-19 patients from around the world to find out how many cases of coronavirus can likely be traced to asymptomatic people, the report added.

India does not test asymptomatic people.

The Indian Council of Medical Research (ICMR) guidelines state that only symptomatic people are to be tested for Covid-19. On May 18, another guideline was issued that stated that "asymptomatic high-risk and direct contacts of those who have tested positive should be tested." This could prove to be a threat if at all asymptomatic patients turn out to be the super-spreaders of the fatal infection.

According to health ministry estimates, close to 80 per cent cases in India are deemed to be "asymptomatic" as per health ministries own estimates, 20 per cent show symptoms, about 15 per cent are hospitalised and only 5 per cent need critical care such as oxygen or ventilators.

The COVID-19 peak is yet to come in the country and is expected to happen somewhere in mid-June or early July.