Testing for COVID-19 at the moment has plenty of limitations.
Right now, the current clinical approach tests directly for the presence of the virus in the blood of an infected person. But the limited availability of these PCR (polymerise chain reaction) tests has meant that only those with the most serious cases of COVID-19 have been diagnosed. That’s made it difficult if not impossible for researchers to get a handle on how many people are asymptomatic carriers of the virus, or how it is spreading throughout the community.
On top of that, false negatives are common. And once the infection is resolved, PCR-based tests return negative.
But biological anthropologist Thomas McDade has been working with researchers at Northwestern’s Feinberg School of Medicine to develop a new approach that addresses those issues. They are introducing a new test for COVID-19 antibodies that will require only a single drop of blood, collected from a finger prick and dried on filter paper.
This will make testing easier and more widespread on many levels: the test kits can be mailed, and recipients can administer the tests themselves. And the samples can be returned to the lab in the mail, without needing special handling or refrigeration.
The approach relies on the fact that the antibodies specific to the proteins on the virus emerge 10 to 14 days after infection occurs, and remain detectable in the blood long after the infection has resolved. That means researchers can identify who’s been infected long after the fact — even if an individual has been asymptomatic.
McDade and his Feinberg School colleagues are now working to recruit participants in a “proof of principle” effort, which will also generate important data on how widely the virus has spread within the population at large. They are also developing a website that will handle participant registration, survey data collection and the return of test results.
This web-based platform, combined with a blood-collection approach that can be implemented at home with minimal effort and cost, will lay the foundation for a minimally invasive and scalable approach to COVID-19 antibody testing and research.