New Covid-19 test might detect symptoms within 1 day after exposure, say US military scientists
A new test that has the potential to detect Covid-19 in people before they start showing symptoms and before they are considered infectious, has been developed by scientists from the US military. If approved, this could be a gamechanger as asymptomatic people (those who do not show symptoms) can spread the new coronavirus, making it challenging to track and stop its transmission.
This is according to a report by The Guardian, which says that scientists have designed the blood-based test that they hope could detect the virus’s presence as early as 24 hours after infection, four days earlier than current tests. This implies that the carrier could possibly be isolated before they spread the disease. Doing so could dramatically help curb the spread of the novel coronavirus that has killed more than 238,780 globally, and infected over 3,344,400, according to the Johns Hopkins tracker.
People with Covid-19 have reported a wide range of symptoms – ranging from mild to severe illness. People may experience fever, cough, and shortness of breath, among others. According to the US Centers for Disease Control and Prevention (CDC), symptoms may appear 2-14 days after exposure to the virus.
“Project coordinators hope the blood-based test will be able to detect the virus’s presence as early as 24 hours after infection – before people show symptoms and several days before a carrier is considered capable of spreading it to other people. That is also around four days before current tests can detect the virus,” reports the Guardian.
The blood test came out of a project by the US military’s Defense Advanced Research Projects Agency (DARPA), which aims at diagnosing germ or chemical warfare poisoning, and was repurposed for the coronavirus pandemic. “DARPA is working on several fronts to bring the latest science and technology to overtake the challenges posed by Covid-19, with active research programs focused on the diagnosis, detection, treatment, prevention, and manufacture of medical countermeasures,” says a statement.
The new test is expected to be put forward for emergency use approval (EUA) by the US Food and Drug Administration (FDA) within a week. Researchers said the test looks at the body’s response to the virus and should provide results earlier than nose-swab tests that “hunt for the virus itself.” If EUA is granted, experts can start using the test from the second half of May.
“The goal of the research is to develop and validate an early host blood response diagnostic test for Covid-19 Because the immune response to infection develops immediately after infection, a Covid-19 signature is expected to provide more sensitive Covid-19 infection diagnosis earlier,” Professor Stuart Sealfon, who leads the research team at Mount Sinai hospital in New York, says in the report.
“The concept fills a diagnostic gap worldwide” since it should also fill in testing gaps at later stages of the infection, Dr Brad Ringeisen, the head of Darpa’s biological technologies office, told the Guardian.
However, the prediction that the test might be able to identify carriers before they become infectious is currently based on previous research into other viruses. “We have evidence that diagnosis happens in the first 24 hours for influenza and an adenovirus. We are still in the midst of proving that with Covid-19. That said, we should know very soon after EUA,” Dr Eric Van Gieson, who redirected DARPA’s epigenetic characterization and observation program (ECHO) to focus on Covid-19, told the Guardian.
The ECHO program aims to reduce the threat posed by weapons of mass destruction. “ECHO technology would work by quickly reading an individual’s epigenome — a part of human biology that helps our body respond to the constantly changing world around us — and identifying the epigenetic signatures indicative of weapons of mass destruction, precursor, or infectious disease exposure,” says DARPA.