Rodríguez Grande, CristinaEstévez, AgustínPalomino Cabrera, RosalíaMolero Salinas, AndreaPeñas Utrilla, DanielHerranz, MartaSanz Pérez, AmadeoAlcalá, LuisVeintimilla, CristinaCatalán Alonso, PilarMartínez Laperche, CarolinaAlonso Fernández, Roberto AlfonsoMuñoz García, Patricia CarmenPérez Lago, LauraViedma, Darío García deBurillo Albizua, Almudena2026-01-142026-01-142023-05-02Rodríguez-Grande, C., Estévez, A., Palomino-Cabrera, R., Molero-Salinas, A., Peñas-Utrilla, D., Herranz, M....de Viedma, D. (2023). Early SARS-CoV-2 Reinfections Involving the Same or Different Genomic Lineages, Spain. Emerging Infectious Diseases, 29(6), 1154-1161. https://doi.org/10.3201/eid2906.221696.1080-60401080-605910.3201/eid2906.221696https://hdl.handle.net/20.500.14352/130201La investigadora Almudena Burillo pertenece a Gregorio Marañón Microbiology-ID COVID 19 Study Group y realiza su aportación como autora colaboradora. Fondo Europeo de Desarrollo Regional (FEDER) – A way of making Europe European Centre for Disease Prevention and Control (ECDC)Centers for Disease Control and Prevention guidelines consider SARS-CoV-2 reinfection when sequential COVID-19 episodes occur >90 days apart. However, genomic diversity acquired over recent COVID-19 waves could mean previous infection provides insufficient cross-protection. We used genomic analysis to assess the percentage of early reinfections in a sample of 26 patients with 2 COVID-19 episodes separated by 20–45 days. Among sampled patients, 11 (42%) had reinfections involving different SARS-CoV-2 variants or subvariants. Another 4 cases were probable reinfections; 3 involved different strains from the same lineage or sublineage. Host genomic analysis confirmed the 2 sequential specimens belonged to the same patient. Among all reinfections, 36.4% involved non-Omicron, then Omicron lineages. Early reinfections showed no specific clinical patterns; 45% were among unvaccinated or incompletely vaccinated persons, 27% were among persons <18 years of age, and 64% of patients had no risk factors. Time between sequential positive SARS-CoV-2 PCRs to consider reinfection should be re-evaluated.engjournal articlehttps://doi.org/10.3201/eid2906.221696https://wwwnc.cdc.gov/eid/article/29/6/22-1696_articlerestricted access616.98578.828579.26614.4SARS-CoV-2reinfección tempranavariantesOmicronsecuenciación genómicaepidemiología molecularMedicina32 Ciencias Médicas