(Dr.Soumya Swaminathan , WHO chief scientist)   

               Asymptomatic covid cases never have symptoms even though you are positive, detected to be so by tests; no symptoms, even after follow up.

When I have a test today. I’m found positive. I am perfectly fine today, but two days later, I develop symptoms like fever, lethargy, loss of smell etc. And, of course, symptomatic is when you have symptoms at the time you are tested.

Now, in order to find out if asymptomatic or pre-symptomatic cases are spreading the infection, what you need to do is, follow a large number of people, what we call a cohort. You test them, they turn out positive, you follow them up for over 7-10 days to find out what happens next. And follow their contacts.

A few studies from around the world have shown that people are most infectious 1-3 days before they develop symptoms and for up to five days after symptoms. So effectively, what it means is that when you have no symptoms, you can still be spreading it or carrying the virus. That is why the guideline of wearing facemasks is universal when you cannot maintain that distance of more than one meter between people.

Yes! Asymptomatic and pre-symptomatic people can spread the infection, though most of the infections are probably coming from symptomatic cases. But, in order to control it, both groups need to be monitored. There are studies that suggest 60% spread is from symptomatic.

(Shailaja Teacher, Health Minister, Kerala, India)    

               I first read about the virus spreading on the Wuhan University premises. I read that the virus is SARS (Severe Acute Respiratory Symptom) and there was MERS (Middle East Respiratory Symptoms) from the same virus family and they later named it COVID-19. Whatever the name, the virus was dangerous and its infectivity was high. The first thought that came to my mind was the Kerala students studying in Wuhan. I soon called Health Secretary.

We have to be on alert and immediately start preparations, convene a Rapid Response Team and start a control room.  We sent a message to all District Medical Officers that a virus has been reported and chances are that it would come to Kerala catching a flight.

The flight from Wuhan arrived. Many of the passengers were not symptomatic still  they were sent to home quarantine with instructions.

We didn’t stop surveillance at the airports. Health workers continued testing passengers with thermometers. Some people even asked why we should continue the checks, saying we were creating panic, that we were overdoing it and people would make fun of it.

 Even the opposition said in the Assembly that we should look at what the US is doing. My reply was that we can’t let the people of the state die; we will not follow anyone but learn lessons from all. We had a standard protocol that we have set for the state, though we follow the WHO guidelines as well.