CDC is conducting a number of large-scale geographic seroprevalence research to be taught extra in regards to the proportion of individuals in the USA who’ve been contaminated with SARS-CoV-2, the virus that causes COVID-19. This includes working with state, native, territorial, educational, and business companions to raised perceive COVID-19 in the USA utilizing serology testing (antibody testing) for surveillance (“seroprevalence surveys” or “serosurveys”). CDC additionally needs to raised perceive how the virus is spreading by the US inhabitants over time. As a result of contaminated individuals can have delicate sickness or no signs (and subsequently may not get medical care or testing), CDC is collaborating with business laboratories and blood assortment facilities on quite a lot of large-scale geographic seroprevalence surveys throughout the USA.
These seroprevalence surveys use blood exams to determine individuals in a inhabitants who’ve antibodies towards SARS-CoV-2. Antibody check outcomes can present details about earlier infections in individuals who had many, few, or no signs. It isn’t but recognized if having SARS-CoV-2 antibodies can shield towards getting contaminated once more. Proof means that detectable antibodies in some sufferers would possibly lower over time when utilizing sure exams. CDC’s seroprevalence surveys aren’t designed to offer data on how lengthy antibodies final in individuals’s physique following an infection.
Seroprevalence surveys undertaken with business laboratories started in 10 websites that reported early group transmission of SARS-CoV-2 in the USA. Business laboratory seroprevalence surveys have now been expanded to all 50 states, the District of Columbia, and Puerto Rico. CDC can be conducting a nationwide seroprevalence survey amongst individuals who donate blood.
In decoding the seroprevalence survey outcomes, it is very important observe that these outcomes may not be generalizable nationwide as a result of individuals who donate or submit blood for laboratory exams is likely to be completely different from the final inhabitants. As well as, survey estimates is likely to be affected by false-positive check outcomes (the check result’s optimistic, however the particular person does probably not have antibodies to SARS-CoV-2) or false-negative check outcomes (the particular person has antibodies to SARS-CoV-2, however the check doesn’t detect them).