Document Type : Original Article






There is sparse longitudinal data on SARS-CoV-2 re-infection after previous infection and after partial or full vaccination.


1) Clinically and epidemiologically characterize COVID-19 reinfection cases; 2) To examine whether the risk of SARS-CoV-2 reinfection has changed over time in the context of the appearance of beta, delta and omicron variants.


An observational, longitudinal and prospective study of Covid-19 re-infections was conducted from March 1, 2020 to July 1, 2022, in a general medicine office in Toledo, Spain.


43 cases were included; with 45 reinfections (2 cases presented 2 reinfections). The mean time from primary infection to reinfection was 346 days (range: 95-813 days). The mean age was 41 years (range: 17-70 years). 5% were >= 65 years. 56% were women. 14% were ethnic minority. 82% of the reinfections occurred in those vaccinated (19%, 28% and 35% in those vaccinated with 1 dose, with 2 doses and with booster, respectively). In 96% they were symptomatic. All cases of reinfection were mild, with general symptoms predominating (discomfort, asthenia, myalgia, fever, arthralgia) (39%). Chronic diseases were present in 60% of reinfection cases, with a predominance of the Genitourinary (19%), Endocrine (17%), and Respiratory system (16%) groups. Reinfections have been increasing progressively since 2020, and 67% occurred in 2022.


We found evidence of a continuous increase in the number of reinfections, and mainly from January 2022, which is temporally consistent with the appearance of the omicron variant, suggesting its increased ability to infect previously infected individuals.


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