Study by Hyderabad researchers finds Covid reinfection possible without mutation

17-02-2021

Some city-based researchers have found that Covid, even without changes in its surge protein, is capable of causing reinfection. The researchers have given two examples, one confirmed and another possible case, from the country. Till now it was believed that various strains with mutations in the spike protein can cause reinfection. Though they did not mention the city from where the cases were recorded, it is believed that the patients are from the city. Researchers from the Centre for Cellular and Molecular Biology and Apollo in the city, say that their analysis of reinfection without mutations in the spike protein highlights the requirement for more research to understand the genetic and molecular underpinnings of Covid reinfections. The result of the analysis was published last night in the Oxford University publication, Clinical Infectious Diseases. Two cases of Covid reinfections from the country and corresponding whole genome sequencing data, confirmed using two orthogonal sequencing technologies. The analysis said, �Nextstrain analysis revealed that all the four viral genomes belonged to the 20B clade and carries the D614G mutation in spike. In both cases, no variation from S or E genes was identified between reinfections.� The researchers cannot rule out the possibility of prolonged viral shedding and accelerated viral evolution because of immune-compromised state. According to the study, most recorded reinfections show the presence of at least one novel variation in structural proteins between episodes, the spike protein, the two cases recorded by the researchers showed no variation in the spike protein of Covid between episodes. The first case is of a senior citizen testing positive twice within three months. The second case is of a 38-year-old man with symptoms of headache and fever testing positive on November 4. After a day of symptoms, the patient was symptom-free. On November 22, the patient had fever again. Sample collected on that day tested positive. According to the study, other than five days of fever after the test, there were no symptoms during the second episode.