The first confirmed case of a second infection in the United States is more serious than the first, according to new research, and the reason is not yet clear, with researchers speculating that it may be because patients were exposed to a large number of viruses. The first confirmed case of a second case of the new coronavirus in the United States was a 25-year-old man from Nevada, and a paper on his condition was published in the medical journal The Lancet on October 12.
Usa Today reported on October 12 that the man had been feeling unwell since the end of March, with symptoms including a sore throat, cough, headache, nausea and diarrhea. Heather Kerwin, a senior epidemiologist with the Washoe County Health District in Nevada and one of the authors of the paper, said the man tested positive for the new coronavirus on April 18. On 27 April, he reported that his symptoms had all eased and he was feeling well. However, he has been isolated at home because employees are required to test negative for two new crowns before returning to work.
A month later, the man felt unwell again and his symptoms ben more severe. On 31 May, he went to an emergency care centre and reported fever, headache, dizziness, cough, nausea and diarrhoea. On 5 June, he went to the doctor, who found that his blood oxygen levels were extremely low.
Reported that the man, although there are still antibodies to the virus in the blood, but his new coronavirus test again positive. The study found a difference between the two strains of the virus, suggesting that it was indeed a secondary infection. Researchers say the rate at which the new coronavirus mutates in a person is not enough to explain the difference between the two strains.
The study said the man may have been re-infected by exposure to a longer number of viruses, possibly from family members. A family member who lived with the man was also diagnosed with neo-crown pneumonia on 5 June.
Mark Pandori, a pathologist at the University of Nevada and director of the Nevada Public Health Laboratory, said it was not clear why the man was more seriously infected. The paper makes different assumptions: that the virus is higher, resulting in secondary infection and a more serious illness, or that the virus is more toxic this time, or that it is due to increased antibody dependence.
Reported that at least 22 cases of secondary infection have been reported worldwide, but it is still unclear how many cases there are, or how common secondary infections are among people who do not know they have been infected.
Pandora’s case means that even people infected with the new crown need to protect themselves by wearing masks, avoiding large gatherings, washing their hands and keeping social distances.
It also means that so-called group immunity cannot be obtained through natural infections, the report said. It should be noted, however, that vaccines do not protect against natural infections. Iwasaki, an immunologist at Yale University, says the vaccine is designed to induce higher levels of antibodies and lead to more lasting immunity.
Paul Offit, an infectious disease specialist at Children’s Hospital of Philadelphia and a vaccine expert at the University of Pennsylvania School of Medicine, predicts that the vaccine’s protective effects could last at least a year or two. He says the protection provided by infection or vaccination is not 100% perfect, but will gradually disappear, so people exposed to large amounts of the virus may re-infect within a few months, while others may receive years of protection.