Herd immunity doesn’t seem to work for Covid-19: Specialist

IANS

The concept of herd of natural immunity does not seem to work for COVID-19, according to Dr Issac Bogoch, an infectious diseases specialist at the University of Toronto, Canada.

‘Herd immunity’ is when a large percentage of the population becomes immune to an infection, and it can be achieved either through exposure to the infection or via vaccination.

“We have to be very careful with the concept of allowing people to get infected with this virus to develop natural (herd) immunity,” said Bogoch in an interview with IANS.

India Tuesday registered 47,703 fresh COVID-19 cases, and according to one report now has the fastest growth rate of COVID-19.

In an interview with IANS, Bogoch said that without a vaccine, even an imperfect one, it would not be possible to eliminate SARS-CoV-II or the novel coronavirus, which causes COVID-19.

Excerpts:

Dr Issac Bogoch

Recently, few experts recommended that schools may be reopened in New Delhi, as this may help in developing herd immunity. Do you think this concept of herd immunity is really going to work in bringing things back to normal? Would children not act as carriers of the virus infecting the adults in their family and neighborhood?

We have to be very careful with the concept of allowing people to get infected with this virus to develop natural (herd) immunity. This approach does not seem to work (in this case). This is a very contagious infection, and it is clear that the virus can be devastating to those over the age of 60 or with underlying medical conditions. Also, in many areas that had widespread epidemic, once they have their epidemic under control, these areas are still far from what it may take to reach some degree of herd immunity.

In India, a trend has been noticed that patients who have recovered from the viral infection have had their lungs in bad shape. Also, COVID-19 is considered responsible for strokes and neurological disorders. Could we say COVID-19 is no longer a respiratory disease?

Many respiratory infectious diseases, including COVID-19, have manifestations outside of the lungs. We are seeing examples of clinical issues outside of the lungs in those with COVID-19, such as blood clots, and smell and taste disturbances.

Is it possible to eliminate COVID-19 anytime soon? How long do you think people would have to wear masks and adhere to social distancing norms? is the virus going to stay with us for a long time?

Unfortunately, in much of the world I do not think it is possible to eliminate COVID-19 in the pre-vaccine era. That doesn’t mean we should not strive toward elimination. We should do everything possible to keep community transmission as low as possible. But, for most places, elimination is an unrealistic goal. Even if the infection is eliminated in some small region, it can be easily re-imported once travel resumes. A vaccine, even an imperfect vaccine, will significantly help with elimination strategies.

Do you think the Oxford vaccine has the potential to be a real game-changer, not only for a COVID-19 vaccine but for the development of future vaccines?

The results of the Oxford COVID-19 vaccine from Phase 1 and Phase 2 clinical trials look very promising, but we still need to be patient and wait for Phase 3 clinical trial results, which will inform us on if this vaccine reduces the chances of acquiring COVID-19. This vaccine and others in development stages look extremely promising, but I do not want to get overly excited just yet — let’s see how these vaccines perform in larger clinical trials first.

The Oxford-AstraZeneca vaccine has produced a promising immune response in a large, early-stage human trial. Do you think this is the step towards developing a vaccine providing long-lasting protection against COVID-19?

This is a major step forward. We still need to see the results of larger human trials, and these are ongoing for this vaccine and a few other COVID-19 vaccines too. An effective vaccine will be an essential step toward returning to life as we remember before COVID-19.

Also see

Oxford COVID-19 vaccine to ‘start reaching masses in India by 2021 first quarter’