What is the post-vaccination (post vaccination) status test?

From the Guidelines

Post-vaccination status testing is recommended for certain individuals, including health care personnel, public safety workers, hemodialysis patients, HIV-infected persons, and other immunocompromised persons, as well as sex partners of HBsAg-positive persons, and should be performed 1-2 months after administration of the final dose of the vaccine series to determine the need for revaccination and the type of follow-up testing. The testing should consist of anti-HBs and HBsAg, and persons with anti-HBs concentrations of ≥10 mIU/mL are considered to be immune 1. According to the most recent guidelines, postvaccination serologic testing is necessary for persons whose subsequent clinical management depends on knowledge of their immune status, including certain health-care and public safety workers; chronic hemodialysis patients, HIV-infected persons, and other immunocompromised persons; and sex or needle-sharing partners of HBsAg-positive persons 1. Persons found to have anti-HBs concentrations of <10 mIU/mL after the primary vaccine series should be revaccinated, and administration of all doses in the second series, on an appropriate schedule, followed by anti-HBs testing 1-2 months after the final dose, is usually more practical than serologic testing after one or more doses of vaccine 1. Some key points to consider when evaluating post-vaccination status include:

• The need for revaccination and follow-up testing
• The type of vaccine and vaccination schedule used
• The individual's immune status and risk factors for infection
• The presence or absence of antibodies and their correlation with protection against disease
• The potential for false-negative or false-positive test results
• The cost and availability of testing
• The potential benefits and risks of revaccination and follow-up testing. It is essential to follow the recommended vaccination schedule and to discuss any concerns about immune response with a healthcare provider, especially for individuals who are immunocompromised or have a high risk of exposure to infectious diseases 1.

From the Research

Post-Vaccination Status Testing

• The v-safe after vaccination health checker is a tool used to monitor COVID-19 vaccine safety, allowing individuals to report post-vaccination experiences and symptoms 2.
• Studies have shown that COVID-19 vaccines are well-tolerated and induce effective antibody responses in individuals with chronic hepatitis B virus infection 3.
• SARS-CoV-2 serological testing can be used to diagnose recent prior infection, isolate high-titer convalescent plasma, and diagnose multisystem inflammatory syndrome in children (MIS-C) 4.
• COVID-19 vaccines may be involved in reducing hepatitis B surface antigen (HBsAg) levels in patients with chronic hepatitis B 5.
• Serological testing patterns for COVID-19 have been studied in various populations, including those pre- and post-vaccination rollout 6.

Key Findings

• A study of 9,342,582 individuals who submitted 131,543,087 v-safe surveys found that the majority of participants were female (62.3%) and non-Hispanic White (61.2%), with a median age of 49.0 years 2.
• Inactivated COVID-19 vaccines were found to be well-tolerated and induced effective antibody responses in 362 adult patients with chronic hepatitis B virus infection 3.
• A review of established clinical use cases for SARS-CoV-2 antibody measures found that an antibody correlate of protection (CoP) for SARS-CoV-2 has not been successfully defined, but may be defined for prevention of severe disease requiring hospitalization and/or death 4.
• A study of three clinical cases found that HBsAg levels rapidly decreased after injection of the COVID-19 vaccine without any incentive, suggesting that COVID-19 vaccines may be involved in HBsAg reduction 5.
• A study of 10,416 individuals who presented for SARS-CoV-2 antibody tests found that seropositivity increased from 9.2% in the pre-vaccine launch period to 46.7% in the post-vaccine launch period 6.