From ABCNews: Antibody research indicates coronavirus may be far more widespread than known
Of 3,300 people in California county up to 4% found to have been infected.
By A critical question in the path towards the future is how many people actually have protective novel coronavirus antibodies and possible immunity? Two research teams in California — backed by armies of dedicated volunteers — set out to answer this very question and the first set of results are in.
The first large-scale community test of 3,300 people in Santa Clara County found that 2.5 to 4.2% of those tested were positive for antibodies — a number suggesting a far higher past infection rate than the official count.
Based on the initial data, researchers estimate that the range of people who may have had the virus to be between 48,000 and 81,000 in the county of 2 million — as opposed to the approximately 1,000 in the county's official tally at the time the samples were taken.
“Our findings suggest that there is somewhere between 50- and 80-fold more infections in our county than what’s known by the number of cases than are reported by our department of public health," Dr. Eran Bendavid, the associate professor of medicine at Stanford University who led the study, said in an interview with ABC News' Diane Sawyer…
The article notes that Dr. John Brownstein, an epidemiologist at Boston Children's Hospital and ABC News contributor, said that the results may not be representative of the US population, and the use of online ads to obtain subjects could "skew the candidate pool." He also said the study confirms that the number of of people exposed is likely much higher than we know from testing people with symptoms.
"There has been wide recognition that we were undercounting infections because of lack of testing or patients were asymptomatic," Brownstein said.
If the study is correct and there are many more people who have very mild or asymptomatic COVID-19 cases, then the death rate is lower than it appears to be from looking at only known cases.
I also wonder whether the researchers can be absolutely sure that the antibodies they are measuring are completely specific for COVID-19. I didn't see anything about that in the article. (Ilene)
Image by Elliot Alderson from Pixabay
