US Likely Far Off From Herd Immunity: Less Than 10% Have COVID Antibodies
A new study published in The Lancet found that only 9% of 28,500 blood samples from dialysis patients in 46 states tested positive for coronavirus antibodies.
About 9% Of Americans Exposed To COVID-19 By Midsummer. That's A Long Way From Herd Immunity.
By the end of July, about 9% of American adults had been exposed to the coronavirus that causes COVID-19, according to a new study of dialysis patients, the largest yet looking for evidence of the disease in people's blood. The infection rates varied from essentially zero in some states that avoided infection by midsummer, to more than one-third of residents in parts of New York hard-hit in the spring. The upshot is the American public is a long way from achieving "herd immunity" – having enough infections to prevent further spread of the virus. (Weintraub, 9/25)
Less Than 10% Of U.S. Show Signs Of Past Coronavirus Infection, Study Finds
The researchers arrived at their findings by studying the prevalence of coronavirus antibodies, which the immune system typically generates in response to an infection, in a group of randomly selected dialysis patients across the country. Even people with coronavirus antibodies are not necessarily immune to the virus, as scientists are still trying to understand how much protection antibodies create and how long that protection might last. The finding that more than 90% of the country does not have antibodies is in line with conclusions of another study by the Centers for Disease Control and Prevention, which has not yet been published, according to CDC Director Dr. Robert Redfield. (Feuer, 9/26)
New York Post:
New Study Says US Is Nowhere Near COVID-19 Herd Immunity
In some states, the infection rate was essentially zero, according to the study, which tested plasma samples from more than 28,000 randomly selected dialysis patients from across the US. In New York, the rate was 33.6%, by far the highest in the nation, with the rate largely skewed toward downstate counties. The next highest was Louisiana, at 17.6%. New Jersey’s rate was just 11.9%. Nationwide, the infection rate was just 9%. Herd immunity means that enough people are infected to prevent further spread of the virus. Experts say for the coronavirus, that would about 50 to 65% of the population. (Connelly, 9/26)
In related news about herd immunity —
In Brazil's Amazon A COVID-19 Resurgence Dashes Herd Immunity Hopes
The largest city in Brazil’s Amazon has closed bars and river beaches to contain a fresh surge of coronavirus cases, a trend that may dash theories that Manaus was one of the world’s first places to reach collective, or herd, immunity. When a large portion of a community becomes immune to a disease, its spread becomes unlikely. University of Sao Paulo researchers suggested that a drastic fall in COVID-19 deaths in Manaus pointed to collective immunity at work, but they also believe that antibodies to the disease after infection may not last more than a few months. (Boadle, 9/27)
The Toll Of Reaching Herd Immunity Without A COVID-19 Vaccine
There has been a lot of talk lately about the United States using herd immunity to combat the COVID-19 pandemic. In a recent town hall with ABC News, President Donald Trump repeated claims that the coronavirus would “go away [during] a period of time” because people would develop a “herd mentality.” He obviously meant herd immunity, or when a high enough number of people are immune to a disease so it can’t spread through the population. However, the president’s assertion isn’t true. (Krans, 9/27)