Immunoglobulin G and neutralizing antibody response after CoronaVac

Area of Science:

• Immunology
• Vaccinology
• Virology

Background:

• Healthcare professionals are a priority group for vaccination.
• Understanding immune responses to vaccines like CoronaVac is crucial for public health.

Purpose of the Study:

• To assess the kinetics of immunoglobulin G (IgG) and neutralizing antibody responses after CoronaVac vaccination.
• To evaluate immune responses in healthcare professionals.

Main Methods:

• A cohort of 35 healthcare professionals was studied.
• Blood samples were analyzed for IgG and neutralizing antibodies against SARS-CoV-2.

Main Results:

• IgG seroconversion peaked at day 30 (68.2%) and stabilized by day 90.
• Neutralizing antibody detection rates for Wuhan and B.1.1.7 variants remained stable, but were lower for B.1.351 and P.1.
• Neutralizing antibody levels decreased significantly by day 90 among IgG-positive individuals.

Conclusions:

• CoronaVac induces robust IgG seroconversion.
• Neutralizing responses against emerging SARS-CoV-2 variants wane over time.
• Booster doses may be necessary to maintain protection against variants.