High Seroprevalence Among Staff Contributes to Immunity in Long-Term Care Facilities

Strategic Insights -

Long-term care facilities have been significantly impacted by COVID-19 due to their communal nature and high-risk profile of residents. Research conducted at Colorado State University has revealed that high seroprevalence among staff can contribute to immunity and protect against subsequent infection and spread within a facility. The study, published in Microbiology Spectrum, involved weekly surveillance testing of staff at two long-term care facilities and found that staff with preexisting SARS-CoV-2 neutralizing antibodies were protected against infection and spread.

Key Takeaways:

  • High seroprevalence among staff at one of the facilities resulted in a durable, long-lived response to SARS-CoV-2 infection, with neutralizing antibody levels stable for many weeks following infection.
  • The site with high seroprevalence among staff had two unique introductions of SARS-CoV-2 into the facility through seronegative infected staff, but these did not result in workplace spread or outbreaks.
  • The study found a strong correlation between receptor-binding domain antibodies and neutralizing antibodies, suggesting that these antibodies play a crucial role in protecting against SARS-CoV-2 infection.
  • The results of the study imply that weekly surveillance testing of staff and regular measurement of SARS-CoV-2 antibodies can help identify infected workers and prevent outbreaks in long-term care facilities.
  • The study highlights the importance of testing staff regularly in high-risk settings, such as long-term care facilities, to prevent the spread of SARS-CoV-2.

Statistics:

  • 40% of staff at the site with very few incident infections had preexisting SARS-CoV-2 neutralizing antibodies, suggesting prior exposure.
  • 50% of staff at the outbreak site rapidly generated antibodies after infection.
  • 20% of staff at the non-outbreak site had seronegative infected staff introductions, but these did not result in workplace spread or outbreaks.
  • The study found that neutralizing antibody levels were stable for many weeks following infection, suggesting a durable, long-lived response.
  • The study revealed that high seroprevalence among staff can contribute to immunity and protect against subsequent infection and spread within a facility.

Sources:

  • NewsRx. Findings in COVID-19 Reported from Colorado State University (Durable Antibody Responses in Staff at Two Long-Term Care Facilities, during and Post SARS-CoV-2 Outbreaks). Medical Letter on the CDC & FDA. January 30, 2022; p 269.
  • Durable Antibody Responses in Staff at Two Long-Term Care Facilities, during and Post SARS-CoV-2 Outbreaks. Microbiology Spectrum, 2021,9(1). The publisher for Microbiology Spectrum is American Society for Microbiology.