According to Jeffrey Shaman, professor of Environmental Health Sciences at the Columbia University Mailman School of Public Health, the main obstacle to ascertaining reinfection numbers is that SARS-CoV-2 - unlike other coronaviruses that circulate among humans - is brand new, epidemiologically speaking.
Thirty five days later, he was rushed to the emergency room, short of breath and with a raging fever, and placed on oxygen support.
iStockScientists showed that susceptibility to Covid-19 is independent of age, while occurrence of symptomatic COVID-19, severity and mortality is likely dependent on age. According to reports, a Dutch woman has become the first to pass away after being reinfected with COVID-19.
A 25-year-old man from Nevada is the first person in the United States to contract COVID-19 twice.
"Based on what we know about COVID-19, it would be too risky to try to achieve herd immunity through natural exposure to this virus, as it can be lethal or detrimental in people of all ages".
Reinfections imply so-called herd immunity can not be obtained just through natural infection.
"So it could be that you need repeated (COVID-19) vaccinations all the time". The findings add that coronavirus survives for longer in cooler weather. They had the benefit of sequencing equipment on campus, as well as microbiologists, he said. It is unclear how many actual cases there have been, and how common reinfection is among people unaware they have been infected. Iwasaki asked, noting that while differences in the viral genome sequence of different isolates indicate reinfection, "it does not indicate that the second infection was due to immune evasion". The virus was then extracted after a period of time and tested to determine how infectious it was. It's possible the second version was more unsafe, though there is no evidence of that, or that it was just different enough that his body didn't recognize it, the paper said.
The fact that all 5 cases of confirmed reinfection involved patients who displayed symptoms with the second infection suggests that many more cases of reinfection may have occurred but were not detected in asymptomatic patients, the researchers wrote. Instead, protection fades gradually, so someone exposed to a huge dose of the virus might get re-infected within months, while others could be protected for years.