Poster Presentation Lorne Infection and Immunity 2022

The Persistence of Neutralising Antibodies up to 11 months after SARS-CoV-2 Infection in the Southern Region of New Zealand   (#188)

Reuben McGregor 1 2 , Alana Whitcombe 1 , Alyson Craigie 3 , Susan Jack 4 , Arlo Upton 5 , James Ussher 2 3 6 , Nicole Moreland 1 2
  1. University of Auckland, Auckland, AUCKLAND, New Zealand
  2. Maurice Wilkins Centre and School of Medical Sciences, The University of Auckland, Maurice Wilkins Centre and School of Medical Sciences, Auckland, New Zealand
  3. Southern Community Laboratories, Dunedin, New Zealand
  4. Public Health South, Southern District Health Board, Dunedin, New Zealand
  5. Southern Community Laboratories, Dunedin, New Zealand, Dunedin, New Zealand
  6. Public Health South, Southern District Health Board, Dunedin, New Zealand

Circulating antibodies are important markers of prior infection and protective immunity. Questions remain with respect to the durability and functionality of SARS-CoV-2 antibodies. We comprehensively analysed the antibody dynamics of 189 PCR-confirmed COVID-19 cases up to 8 months post-infection in New Zealand following the first nation-wide lockdown in 2020. We found that neutralising antibodies to the ancestral strain, were relatively stable over the study period. Due to the emergence of SARS-CoV-2 variants of concern (VoC) we subsequently extended the analysis of neutralising antibodies in 78 of these COVID-19 cases from the Southern region up to 11 months post-infection against the alpha, beta and delta  VoC. There was no known community transmission in the region over the study period due to New Zealand’s elimination status at the time, nor had any participants received a COVID‑19 vaccine. In the absence of re-exposure, antibody reactivity to the viral spike protein, as well as neutralising antibodies to both the ancestral strain and the delta variant remained relatively stable between 8 and 11 months post-infection. This suggests long-lived antibody responses can be generated from a single natural infection event. However, given the risks of serious disease associated with SARS-CoV-2 infection and the recent emergence of the omicron variant, vaccination remains strongly recommended. Assessement of omicron neutralisaing antibodies in the cohort are underway and will be presented.