Chembio DPP COVID-19 IgM/IgG Serological Testing: Laboratory Validation, Guidelines, and Recommendations.

Area of Science:

• Infectious Disease Epidemiology
• Clinical Diagnostics
• Public Health Surveillance

Background:

• The COVID-19 pandemic, declared by WHO in January 2020, necessitated rapid diagnostic advancements.
• Richmond University Medical Center evaluated Chembio's serological IgM/IgG testing during this period.
• Serological tests offer a complementary approach to molecular diagnostics like RT-PCR.

Purpose of the Study:

• To assess the performance of Chembio COVID-19 IgM/IgG serological testing.
• To evaluate its utility as an employee screening tool in a community hospital setting.
• To inform hospital policies regarding screening and management algorithms.

Main Methods:

• A prospective cohort study involving 1,866 asymptomatic hospital employees.
• Utilized Chembio COVID-19 IgM/IgG serological testing alongside Cepheid RT-PCR analysis.
• Categorized employees into non-exposed, convalescent (IgG only), and potential new infections.

Main Results:

• Identified a 14.9% exposure/convalescent rate among screened employees.
• Observed varied antibody profiles, including IgG elevation only and dual IgM/IgG reactivity.
• A small percentage (<1%) showed dual reactivity with negative PCR follow-up.

Conclusions:

• Chembio's serological test demonstrated satisfactory performance for employee screening.
• Hospitals need to establish clear screening protocols, result interpretation guidelines, and management algorithms for positive cases.
• Effective implementation requires defining screening criteria and developing pathways for employees with dual antibody positivity.