A group of Hungarian swimmers who tested positive for the coronavirus have not shown antibodies in their blood after analysis of samples by a research group.
As we reported in March of this year, nine people affiliated with Hungarian Swimming, including National Team swimmers and staff members, tested positive for coronavirus while partaking in training camps.
Dominik Kozma, David Horvath, Richard Bohus, and Boglarka Kapas were among them but were asymptomatic.
After the aforementioned eventually tested negative and were able to return to training, they donated plasma at the University of Physical Education in Budapest. As we reported, the facility is in cooperation with Semmelweis University and the Virology Research Group of the University of Pecs and OrthoSera Kft. developing plasma therapy.
Per the American Red Cross at the time, people who have fully recovered from COVID-19 were thought to have antibodies in their plasma that can attack the virus. This convalescent plasma is being evaluated as a treatment for patients with serious or immediately life-threatening COVID-19 infections, or those judged by a healthcare provider to be at high risk of progression to severe or life-threatening disease.
Months later, however, the swimmers’ blood donations were analyzed by researchers at the University of Pecs, with the scientists finding no coronavirus antibodies in the samples. In fact, according to an interview with researchers published in Hungary Today, only 1 of 29 prominent Hungarian athletes who donated blood had the coronavirus antibodies contained within it after contracting the disease.
These findings correlate to those rendered in a Chinese study performed in June as well. As published on the University of Minnesota’s Center for Infectious Disease Research and Policy site, 90% of 74 participants, both asymptomatic and symptomatic showed steep declines in levels of SARS-COV-2–specific immunoglobulin G (IgG) antibodies within 2 to 3 months after onset of infection. Further, 40% of the asymptomatic group tested negative for IgG antibodies 8 weeks after they were released from isolation.
There is still hope that those infected with the virus will show a strong T-cell-mediate response, which is another potential form of immunity, as early studies, including one done by the Karolinska Institute, have indicated that T-cell responses have been more common than antibody responses. It is not clear yet, though, how much immunity those T-cell responses will confer, as research is ongoing.