The case involves a 25-year-old Reno man who’d gotten mild symptoms of the disease in April but developed more severe symptoms when he got reinfected in mid-May.
People reinfected with the coronavirus disease 2019 (COVID-19) may suffer more debilitating symptoms of the disease than they did during their first infection, according to a preprint study in the Lancet. The publication notes that the study has not yet been peer-reviewed, and the investigators involved stress that it involves just 1 patient.
“It is crucial to note that the frequency of such a phenomenon is not defined by a singular case study,” write investigators with the medical school at the University of Nevada at Reno and the Nevada State Public Health Laboratory. “This may represent a rare event.”
Still, the implications are far-reaching.
The findings come in the wake of last week’s report that a man in Hong Kong had been reinfected with SARS-CoV-2—the first such instance of reinfection that had been documented—but in that case the virus came back in asymptomatic form.
The US case involves a 25-year-old Reno man who’d gotten mild symptoms of the disease in April but developed more severe symptoms when he got reinfected in mid-May. “Through nucleic acid sequence analysis, the viruses associated with each instance of infection were found to possess a degree of genetic discordance that cannot be explained reasonably through short-term in vivo evolution,” the investigators write in the Lancet study. “We conclude that it is possible for humans to become infected multiple times by SARS-CoV-2, but the generalizability of this finding is not known.”
But anecdotal evidence exists.
In July, D. Clay Ackerly, MD, MSc, an internal medicine and primary care physician in Washington, D.C., writing for Vox described how a patient of his also developed COVID-19 symptoms twice. In his opinion piece, Ackerly, too, was careful to stress that his experience is based on 1 patient only. Still, “the trajectory of a moderate initial infection followed by a severe reinfection suggests that this novel coronavirus might share some tendencies of other viruses such as dengue fever, where you can suffer more severe illness each time you contract the disease.”
The title of that opinion piece: “My Patient Caught Covid-19 Twice. So Long to Herd Immunity Hopes?”
In the case involving the Reno man, the investigators said that the patient developed 2 distinct COVID illnesses from 2 SARS-CoV-2 viruses that were genetically distinct. “This strongly supports that reinfection with SARS-CoV-2 can occur,” they write.
The Reno man was first found to be infected with the coronavirus at a community-based COVID-19 testing event sponsored by the Washoe County Health District on April 18. His symptoms were sore throat, cough, headache, nausea and diarrhea, some of which he said surfaced on March 25. The man was put in isolation and symptoms were gone by April 27. Two nucleic acid amplification tests were conducted to determine whether he was still infected on May 9 and again on May 26.
They were negative for SARS-CoV-2 and the patient was feeling fine but then, 2 days later on May 28, he again began to feel symptoms again: fever, headache, dizziness, cough, nausea, and diarrhea. He got a chest x-ray and was sent home.
However, 5 days later, on June 5, he went to his family physician who then sent him to the hospital emergency department where he was given oxygen.
The investigators referred to the 2 instances of COVID-19 infection as case A and case B. They write “of enormous significance, four of the discordant loci seen between case A and case B would be reversions specific to the ancestral genotype. The odds of this occurring are vanishingly remote and virtually assure that these are two distinct viral infection events. Of course, if such a remarkable event of base change did occur in that timeframe, then the remarkable nature of cases A and B would shift from a case of possible reinfection to a case of high-rate evolution within an infected individual.”
They further write that “an implication of this finding is that initial exposure to the SARS-CoV-2 virus may not result in a level of immunity that is 100% protective for all individuals. With regard to vaccination, this is an established understanding, with influenza regularly demonstrating the challenges of effective vaccine design”