Possible case of US Covid-19 reinfection

A 25-year-old Nevada man appears to be the first documented case of Covid-19 reinfection in the United States. Genetic tests indicate the patient was infected with two different strains of the virus, a team at the University of Nevada Reno School of Medicine and the Nevada State Public Health Laboratory reported. The patient was first diagnosed with coronavirus in April after he experienced a sore throat, cough, headache, nausea and diarrhea, the researchers wrote in a pre-print study posted on Thursday. He got better around April 27, and he tested negative for the virus twice afterwards. But, it's not the first case documented globally. Early last week, Hong Kong researchers said they found the first documented case of coronavirus reinfection in a 33-year-old man. He tested positive for Covid-19 twice this year. What makes the Hong Kong case different is that researchers said the man experienced coronavirus symptoms during his first bout of Covid-19, but that he didn't have any obvious symptoms the second time. "If reinfection is possible on such a short timeline, there may be implications for the efficacy of vaccines developed to fight the disease. It may also have implications for herd immunity," Mark Pandori, the director of the Nevada State Public Health Laboratory, said in a news release on Thursday.