After the first known reinfection in the United States, scientists warn COVID-19 immunity may not be guaranteed.
A 25-year-old Nevada man tested positive for the coronavirus six weeks after he originally contracted the disease, scientists said Monday in The Lancet medical journal.
In the report, researchers studied the viruses that caused the man’s infections and determined they had different genetic makeups. The findings suggest he was infected two separate times.
That means exposure to the virus “might not guarantee total immunity in all cases,” according to the study.
“All individuals, whether previously diagnosed with COVID-19 or not, should take identical precautions to avoid infection,” researchers wrote in their journal article.
During the coronavirus pandemic, the Centers for Disease Control and Prevention has urged people to avoid crowds, wear face masks and wash their hands to help stop the spread of the disease.
The latest details about the Nevada patient’s case were published after research from other parts of the world described patients who had been infected twice. Earlier in the pandemic, health experts said some possible cases could have been due to unreliable tests or viruses that reactivated inside patients’ bodies, McClatchy News reported in May.
About 10% of people who get sick don’t have the antibodies to ward off a second COVID-19 infection, so “they have precisely the same risk as anyone out there,” Danny Altmann, immunology professor at Imperial College London, said Monday in an NPR story.
In the Nevada case, researchers say the Reno-area man tested positive for COVID-19 in April. The patient received two negative tests before receiving a second diagnosis in June, when he had more severe symptoms.
While the study found exposure may not mean a person is completely immune from the virus, its suggestions also have “implications for the role of vaccination in response to COVID-19,” according to researchers.
“The good thing about a vaccine is that it can induce much better immunity, a much longer lasting immunity, than the natural exposure to the virus,” said Akiko Iwasaki, a Yale University immunobiology professor who wasn’t part of the Nevada study, according to NPR.
The team that studied the Nevada case was comprised of people involved in the government, medicine and consulting fields.