Pulmonary function and comparative SARS-CoV-2 RBD-specific IgG antibody response among the COVID-19 recovered group.

Area of Science:

• Pulmonary Medicine
• Immunology
• Infectious Diseases

Background:

• Coronavirus disease 2019 (COVID-19) causes significant morbidity and mortality worldwide.
• Long-COVID symptoms, including abnormal pulmonary function, can persist for months post-infection.
• Understanding long-term respiratory consequences and immune responses is vital for patient care and public health strategies.

Purpose of the Study:

• To assess pulmonary function in individuals recovered from COVID-19.
• To evaluate IgG antibody responses post-vaccination in recovered COVID-19 patients.
• To investigate the relationship between immune response and respiratory health after COVID-19.

Main Methods:

• Prospective case-control study involving 29 COVID-19 survivors and 64 controls.
• Pulmonary function tests (FVC, FEV1, etc.) were performed post-recovery.
• ELISA measured IgG antibody responses up to six months post-vaccination, including a booster dose.

Main Results:

• Pulmonary functional abnormalities were more prevalent in COVID-19 survivors (up to 66%) compared to controls (23%).
• Recovered individuals, especially those with moderate to severe COVID-19, showed higher IgG titers post-vaccination.
• Antibody titers negatively correlated with pulmonary function (FVC, FEV1) and decreased significantly within 90-120 days, necessitating booster doses.

Conclusions:

• Pulmonary function evaluation is essential for assessing long-COVID's impact on respiratory health.
• Vaccination is critical for robust immune response and pandemic preparedness, irrespective of prior COVID-19 infection.
• Booster doses are important for maintaining adequate antibody levels.