Humoral response and neutralising capacity at 6 months post-vaccination against COVID-19 among institutionalised older adults in Argentina

MIGLIETTA, ESTEBAN A.; BALLEJO, CHRISTIAN; RAMIS, LILA; MAZZITELLI, BIANCA; GONZALEZ LOPEZ LEDESMA, MARÍA M.; MIRAGAYA, YANINA; SILVA, ANDREA P.; PASCUALE, CARLA A.; RÍOS, ANTONELLA S.; PONCET, VERÓNICA; CEBALLOS, ANA; AGUIRRE, MARÍA F.; ROSSI, ANDRÉS H.; RODRIGUEZ, PAMELA E.; RALL, PABLO; LÓPEZ MIRANDA, LUCÍA; MARRO, JIMENA; SALVATORI, MELINA; OJEDA, DIEGO S.; GAMARNIK, ANDREA V.

Frontiers in Immunology

Frontiers Media S.A.

Año: 2022 vol. 13

The COVID-19 pandemic has particularly affected older adults residing in nursing homes, resulting in high rates of hospitalisation and death. Here, we evaluated the longitudinal humoral response and neutralising capacity in plasma samples of volunteers vaccinated with different platforms (Sputnik V, BBIBP-CorV, and AZD1222). A cohort of 851 participants, mean age 83 (60-103 years), from the province of Buenos Aires, Argentina were included. Sequential plasma samples were taken at different time points after vaccination. After completing the vaccination schedule, infection-naïve volunteers who received either Sputnik V or AZD1222 exhibited significantly higher specific anti-Spike IgG titers than those who received BBIBP-CorV. Strong correlation between anti-Spike IgG titers and neutralising activity levels was evidenced at all times studied (rho=0.7 a 0.9). Previous exposure to SARS-CoV-2 and age