2025/12/05 by Zhengqi Jiang, Tichao Shan, Yucan Li +7 · 6 voices · 1 citation
Medicine · Immunology and Microbiology · #Long-Term Effects of COVID-19 #COVID-19 Clinical Research Studies #Immune responses and vaccinations
paper · pdf · doi:10.1016/j.ijid.2025.108287
Objectives Growing evidence suggests that lymphocyte subsets are declined in COVID-19 patients, but it is unclear if these alterations persist after widespread exposure to SARS-CoV-2 or how long they last. Methods We analyzed lymphocyte subset data from 40,537 patients across three phases: pre-COVID, mass infection, and post-COVID. The counts of lymphocyte subsets and CD4 + /CD8 + ratios were compared using Mann-Whitney U test or Kruskal-Wallis H test. Monthly post-exposure data were compared with pre-exposure data to assess the persistence of impact on lymphocyte subsets by SARS-CoV-2, and subgroup analyses were performed in patients with cardiovascular disease. Results During mass infection, T cells, CD4 + T cells, CD8 + T cells, NK cells, and B cells dropped significantly. Even 20 months post-infection, CD8 + T cells remained 9.9% below baseline. Baseline lymphocyte subsets differed significantly by sex and age. Immune recovery varied by age and sex, with older adults and males showing prolonged lymphopenia. In cardiovascular disease patients, T lymphocytes remained 72.9% below baseline for 20 months post-infection. Conclusions Our findings redefine SARS-CoV-2 infection as a condition of long-lasting immune compromise. The sustained subnormal lymphocytes—particularly in cardiovascular disease cohorts—highlight a key immunologic feature of long COVID and underscore the need for personalized care.