COVID-19: The number of asymptomatic carriers exceeds estimates
Researchers from the Jagiellonian University, in collaboration with DIAGNOSTYKA medical labs, have carried out a population study in Kraków using the ELISA method in order to determine the prevalence of IgG antibodies characteristic of the SARS-CoV-2 infection. The presence of this particular antibody in the human organism is evidence that a person has already recovered from the illness and may have an increased immunity against it.
The study was performed on volunteers that have neither experienced any signs of infection nor have been previously scheduled for coronavirus testing. The results show that about 2% of Kraków population has already recovered from COVID-19. This suggests that asymptomatic carriers are far more common than it was previously thought. However, we are still very far from achieving herd immunity that would protect us from SARS-CoV-2. One important conclusion is that similar studies should be conducted in other regions of Poland to help monitor the spreading of the virus and take more effective measures against it.
The pilot study was carried out on a group of 1,000 people. The specificity of the test was measured on a control group: 200 people whose blood samples had been taken in 2019. No IgG antibodies were found in this group. Researchers in other European countries are observing similar results.
The project was led by Prof. Krzysztof Pyrć from the JU Małopolska Centre of Biotechnology, Prof. Marek Sanak from the JU Faculty of Medicine and Prof. Jakub Swadźba from DIAGNOSTYKA.
source: Jagiellonian University website