COVID-19 primary infection, reinfection, and its associated clinical presentations

SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus-2), which caused primary COVID-19 infection in millions worldwide, raised significant concerns as viral mutations emerged, leading to reinfections among previously infected and vaccinated individuals. This phenomenon became particularly evident during the second and third waves of the COVID-19 pandemic in India.

The current study observed the rates of reinfections due to SARS-CoV-2 and their relation to vaccination details by retrospectively analyzing the data of patients who had reinfections during the second and third waves of COVID-19.

Among the 458 study participants, 62/458 (13.54%) with primary infection had confirmed re-infection. Of the 458 people infected with COVID-19 for the first time, 60 (13%) were asymptomatic and 398 (87%) were symptomatic. The most frequently observed symptoms were fever during primary (70.3%) and re-infection (72.58%). A statistically significant association was observed between vomiting symptoms and infection status (p < 0.01).

SARS-CoV-2 is re-emerging with new variants and varied presentations, posing a challenge to clinicians regarding specific diagnoses. The symptoms of COVID-19 during primary and re-infection did not differ greatly. Although vaccination protects individuals against reinfections, the exact duration of protection remains unknown and may necessitate booster doses at frequent intervals.