If all goes well, the UCR scientific team is able to generate a complementary test that, unlike the current test being implemented in Costa Rica, will use blood samples. Using this technique, it is calculated that two to three hours could recover from COVID-19 who were in contact with the virus without knowing it.
Serologic (blood) testing would provide a key additional alternative. Currently, to diagnose a patient with COVID-19, Costa Rica uses a test known as a polymerase chain reaction (PCR). Internationally, this method is one of the most important because it allows us to obtain millions of copies of a fragment of the virus and, in this case, to know if it is SARS-CoV-2.
However, that method has some limitations. One of them is that it detects the active virus in a specific time frame. In simpler words, there is an expiration date. Therefore, PCR cannot be used when a person has already been in contact with the virus and recovered, because — most likely — their immune system has already killed off the microorganism.
“PCR is a method that detects genetic information when the virus is active in the person. This test is generally only applied to suspicious patients with an obvious symptom picture. The latter means that the asymptomatic (people without symptoms) may not be being considered, “explained Dr. Madrigal.
The idea of the researchers is to have the necessary scientific knowledge to create the complementary test in the future, which is not intended to replace PCR, but is an ally in diagnosis.