COVID-19: 'No Evidence to Back Them Up' Says Prof. Gagandeep Kang on Interventions Like Curfews and Lockdowns

India has recorded over two lakh new COVID-19 cases and over a thousand deaths in the last 24 hours, with the country surpassing all previous records during the pandemic period in terms of daily numbers.

Testing, contact tracing and isolation have been widely implemented across the world and scientists and experts have made it clear that these are the ways to control the spread of the pandemic. Prof. Gagandeep Kang, a noted Indian virologist and a Professor in the Department of Gastrointestinal Sciences at the Christian Medical College, Vellore, told Newsclick that there was “no question that we need to boost testing. But testing by itself is not enough—we also need high quality contact tracing, testing, tracking and the isolation of infected individuals.”

Prof. Kang elaborated on what went wrong on India’s part, on the mutant strains of the virus and on what needs to be done going forward.

IS TESTING, TRACING AND ISOLATING ENOUGH?

“We have few indicators about how well this has been done and in what proportion of cases. There is also a question of resources; when an area is overwhelmed with cases, is there a point where the test, trace, isolate strategy needs to be delivered at higher quality to those most likely to cause onward spread to the greatest number, or should we try to deliver the ‘something is better than nothing’ approach to a greater number. The test, trace, isolate approach really works best when there is a limited number of cases and really good control is feasible”.

WERE WE PREPARED FOR MUTANT STRAINS, ESPECIALLY THE 'DOUBLE MUTANT'?

“There is no question that we need to boost sequencing. We cannot do this in fits and starts and we must have results available and shared quickly if they are expected to inform our understanding and help focus our efforts. INSACOG is a great start, but it needs to expand its efforts and deliver sequences back to public health authorities and the hospitals that send in the samples quickly. For public health, a SWAT team approach in response to emerging virus variants could slow down virus spread and help with ramping up vaccination to prevent further spread”.

“In addition, we need laboratories capable of studying the viral variants, their ability to cause disease and whether vaccinated individuals are protected or not. This requires a range of scientists from structural virologists to clinicians, epidemiologists and immunologists all working in concert (and quickly).”

ON MEASURES LIKE NIGHT CURFEWS AND LOCKDOWNS, AND THE KUMBH ANOMALY:

“Many of these interventions have no evidence to back them up. Have we compared night curfew to testing and isolation strategies? Or lockdowns to more graded approaches? We should use evidence as far as possible, and if evidence does not exist and we decide on an intervention such as a containment zone, can we at least try to measure the impact of the approach? Right now we have pendulum swings from very tight controls to the approach permitting the Kumbh to go ahead—the inconsistency makes no sense.”

ON THE BEST WAY FORWARD NOW:

“The best ways are the ones we know—prevention of crowding, good masks, testing, tracing and isolation, and vaccination. Add to that the use of much more detailed data on infections collected with quality, integrated and used by health authorities and researchers. From the government, clear communication about the drivers of decision-making would be helpful, as would consistency—apparently random changes in policy and implementation make planning very difficult.”

WHAT DID GO WRONG THOUGH?

“The virus is a respiratory virus—the kind that spread most easily. It is also clear that our earlier thinking that this was a virus that spread through large droplet infections, was incorrect. This virus spreads both through droplets and through smaller particles in aerosols that can reach further and stay suspended in air for a longer period. While we do not know is the exact number of viral particles needed to infect people; it is likely that it is small.”

“We also know very little about the seasonality of the virus and the factors that support its survival in the environment and transmission. We know humidity is likely to matter, but very little else. If there are seasonal drivers, it may take a couple of years for us to figure out what really matters—in India, for example, we have both a post-monsoon and a winter peak of influenza, while more temperate regions see only a winter peak.”

WHAT NEEDS TO BE DONE NOW?

“To decrease or prevent spread we have to prevent infections from happening, and the key measures of control are to identify people who are infected and infectious, and keep them away from others. For the large numbers of potentially infectious people that we do not identify, we should think of everyone as potentially infectious and maintain distance between people, wear good quality masks (many of the cloth masks we see being sold do nothing), spend as little time indoors as possible with people whom we do not know and/or increase ventilation as much as possible.”

“These are simple solutions, we know they work and we do not do them. When layered on top of poor behaviour, we have a variant like the B.1.1.7 that is 40%-60% more infectious than the ancestral variant D614G, which itself spread more easily than the original virus out of Wuhan, then we create opportunities the effective reproductive number of the virus to rise and for exponential increase.”

WHAT CHALLENGES DO THE NEW VARIANTS POSE?

“We have today between 20% and 50% of the population that is already infected and likely protected from disease, but are these individuals still capable of spreading infection.It seemed less likely with the ancestral virus, but with the new variants we do not know whether only previously uninfected people are transmitting the virus. However, with the increase in the reproductive number comes the need to increase the percentage of the population previously infected or vaccinated to slow transmission.”