Researchers at the University of Hong Kong said on Monday that a citizen who recovered from Covid-19 was infected again with the disease caused by the emerging corona virus "SARS Cove 2" after 4.5 months, in the first documented case of re-infection of a person with the disease.
These results indicate - according to the researchers - that the disease, which has claimed more than 800,000 lives around the world, may continue to spread among the Earth's population despite the so-called herd immunity.
The 33-year-old patient recovered from COVID-19 and was discharged from hospital in April. But the examination confirmed that he was diagnosed with the disease again after his return from Spain via Britain on August 15.
The researchers said in their paper, which was accepted by the International Medical Clinical Infectious Diseases Journal and quoted by news agencies, that the patient was apparently in good health previously.
A different strain
And it was found that this person was infected with a different strain of Corona virus than the one he had previously infected with, and his infection remained without symptoms in the second infection.
"The results do not mean that vaccinations will be useless. Immunity that results from vaccination may be different from that caused by natural infection. We will need to wait for the results of the vaccine trials to see how effective it is," Kai-Wang Tu, one of the paper’s senior authors, told Reuters. Vaccines ”.
The Department of Microbiology at the University of Hong Kong said in a statement that this case shows that a person can catch the virus again only a few months after recovering from it, pointing out that the time difference between the two cases of the epidemic is 4.5 months.
They added, "Since immunity may not last long after infection, those who have been infected should be considered for vaccination as well."
On Monday, WHO epidemiologist Maria Van Kerkhove said there was no need to jump to any conclusions regarding the Hong Kong case.
Cases have been recorded of people discharged from hospitals, and they tested positive again for Covid-19 infection in mainland China. However, it was not clear in those cases whether the patients contracted the virus again after complete recovery, as happened to a Hong Kong patient, or whether the remnants of the virus were still in their bodies from the first infection.
Wang Guiqiang, an infectious disease specialist with a group of experts in treating COVID-19, told a press conference in May that the initial count in China of patients who had tested positive again after being discharged from hospitals was between 5 and 15%.
The infectious disease specialist added that one explanation is that the virus was still present in the lungs of patients, but it was not detected in samples taken from the upper parts of the respiratory system.
He added that other possible causes include low test sensitivity and weak immunity, which could lead to continued positive results.
Jeffrey Barrett, an expert and consultant for the Covid-19 genome project at the British Wellcome Sanger Institute, said in e-mailed comments to Reuters that it was very difficult to draw any strong conclusion from observing a single case.
He concluded by saying, "Given the number of infections in the world so far, seeing a single case infected again is not a surprise, even if it is rare."
Source : Agencie
