Nearly 47 million Americans have been infected by coronavirus, study claims

A new study of antibody tests finds that as much as 14.5 percent of the population in the United States may already have antibodies for the Wuhan coronavirus (COVID-19). This potentially puts the country closer to achieving the goal of herd immunity.

This research is according to a study by Pfizer Vaccines, which determined that nearly 47 million Americans had been infected by the coronavirus by Nov. 15. This is 4.3 times higher than the estimated 10.8 million officially recorded cases at the time and double the more than 21.05 million cases recorded by Johns Hopkins University’s Coronavirus Resource Center.

Furthermore, the researchers estimate that around one million have been hospitalized and around 305,000 have died from the virus by Nov. 15.

The researchers analyzed data from four “seroprevalence” surveys. These are antibody tests that estimate the percentage of the population that has been infected with COVID-19. These also help researchers estimate how many people may have developed antibodies against the virus.

The four surveys were conducted between April to August and included responses from more than 95,000 people in 10 different states. They also used data from a fifth survey conducted by the Centers for Disease Control and Prevention in 47 states.

All this data helped the researchers come up with an estimated number of 46,910,006 cases of coronavirus having occurred by Nov. 15.

The team warned that their calculation may be considered a conservative estimate, and future calculations “will change over time as the proportion of persons with infection tested, diagnosed and reported changes.”

Substantial gap needs to be overcome before herd immunity is achieved

“Case reports are dependent on patients seeking healthcare,” said research team leader Dr. Frederick Angulo, who works for Pfizer Vaccines in medical development and scientific and clinical affairs.

Angulo believes that at least 40 percent of all infections are asymptomatic, which means that these coronavirus cases never reach the hospital and may never get recorded in the official tally. (Related: Coronavirus could turn into a seasonal virus, but it will keep spreading until the population achieves herd immunity, say experts.)

It is believed that at least 70 percent of the population needs to become infected with the coronavirus and develop some kind of immunity from this infection before herd immunity is achieved, which will quickly thwart COVID-19’s ability to spread even further through the populace.

“Findings of this study suggest that although more than 14 percent of the U.S. population was infected with SARS-CoV-2 by mid-November, a substantial gap remains before herd immunity can be reached,” read the study which was published in JAMA Network Open.

In their conclusion, the researchers state that despite the 21 million cases that have been recorded and verified, they still want the federal government to roll out a nationwide vaccination campaign.

“While it has always been the case that a major underestimate of the true disease burden with COVID-19 has been present, most parts of the country have not reached herd immunity,” said Dr. Amesh Adalja, an expert on infectious disease at Johns Hopkins.

“This underscores the need for vaccination uptake to be optimal to put this pandemic behind us.”

Given the country’s number of infections, some health experts believe that only less than a third of the population – around 20 percent, in fact – needs to be vaccinated before herd immunity is achieved.

“There’s a false construct out there, there’s a recommendation that we need to get every American immunized in order to get a handle on the pandemic,” said Johns Hopkins professor of surgery and health policy Dr. Marty Makary during an interview with Fox News.

“The reality is that about 25 to 50 percent of Americans have already had the infection and have some natural immunity. Now, we don’t know if that’s a little better, a little worse or the same as vaccinated immunity, but … we may only need to get an additional 20 percent of the population immunized by February or March to really hit those 70 percent herd immunity levels.”

Learn more about the progression of the coronavirus pandemic in the United States by reading the latest articles at Pandemic.news.

Sources include:

DailyMail.co.uk

Coronavirus.JHU.edu

USNews.com