The scientific road to recovery

Los Angeles announced that it will be the first city in the nation to offer coronavirus testing to all residents regardless of whether they are in the throes of it or are entirely asymptomatic. This stands in sharp contrast to the New York order that precludes physicians from performing testing on patients unless they are symptomatic or otherwise meet stringent criteria. New York would do well to follow Los Angeles when it comes to universal testing, as it will give us the clearest understanding of the biology of the coronavirus and provide the data needed to safely reopen society.

As an internal medicine doctor in New York, I have treated coronavirus patients since the start of the pandemic. I have lost count of how many times I have been asked, “When can we return to normalcy?” My answer has been consistent and simple in that one of three things must happen before we can return to normalcy. We must develop a reliable and widely available vaccine, wait for herd immunity, or develop an effective cure or treatment. The challenge is none of these goals is easy to achieve.

To start, I think that it is a tall order to expect a vaccine that can be safely and effectively administered in less than 18 months. If history is any guide, there is little reason for optimism. This is because developing vaccines for similar diseases such as severe acute respiratory syndrome has proven to be tricky and so far impossible. What is the reason? A bad vaccine can be more than simply ineffective because it can trigger a dangerous reaction called immune enhancement of the body. This may result in death.

Herd immunity is accomplished when a sufficient number of people in a specified area have both contracted and recovered from the coronavirus. Many scientists and doctors believe this confers immunity. With mortality rates were originally estimated at 1 percent, that translates to a death toll of over 2 million people, which is an unfathomable price to pay to achieve herd immunity. This does not account for the speculation in certain circles that it might be possible to recontract the coronavirus or that recovering from the coronavirus might not confer immunity in the first place.

More practically, herd immunity is unlikely to come to pass in this nation because most governors have instead opted for stay at home orders and social distancing to stop the spread. Make no mistake, this was the right thing to do. As a result we are seeing a decrease in hospitalizations and deaths to achieve a flattening of the case count curve. This is giving our overall health care system a much needed opportunity to catch up.

Our assumptions about the deadliness of the coronavirus have relied on the case fatality rate, or the number of deaths divided by the number of those who have tested positive. But we do not have an accurate sense of how many people have truly tested positive since only those with severe symptoms were tested. We need the number of asymptomatic people to understand the prevalence and to calculate an accurate mortality rate to contain the spread. It will then allow us to determine the infection fatality rate, or the number of deaths divided by the number of symptomatic and asymptomatic people who have really contracted the coronavirus.

New York has concluded from antibody testing that about 12 percent of the population had the coronavirus in the past, but this limited data only offers a picture of the prevalence of the coronavirus from one month ago and not the incidence of new cases that exist today. Without this data, we have no way of knowing who is currently infected and cannot determine properly how to prevent further spread once we reopen society.

If we want a more accurate picture, we must perform both coronavirus testing and antibody testing on a systematic basis. If we reopen society without a handle on the infection fatality rate, it will lead to a potentially devastating outcome. If we execute broad testing on both symptomatic and asymptomatic individuals and find that perhaps 30 percent or more of the population are asymptomatic carriers, it would mean the infection fatality rate is not as lethal as we thought and would provide a scientific reassurance that we can safely reopen society in the near future.

Just as New York offered a glimpse for the rest of the nation to see how deadly this disease can be in a large metropolitan area, we can lead the way to show other states, and even other nations, how to safely reopen society if we run both coronavirus testing and antibody testing.

Sandra Gelbard is a board certified internal medicine doctor and clinical instructor at Langone Medical Center and Lenox Hill Hospital in New York City. She is a member of the American Medical Association and American College of Physicians and has been featured in numerous news programs.