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# Influenza antibody titres waned by strain, not uniformly, in Michigan and Hong Kong
- URL: https://www.coios.me/influenza-antibody-titres-waned-by-strain-not-uniformly-in/
- Published: 2026-10-19T11:39:57.000Z
- Updated: 2026-10-19T12:37:57.000Z
- Description: H1N1 titres fell in Michigan and two H3N2 strains fell in Hong Kong; other strains changed little.
- Author: Daniel Ryan
- Tags: Behavioural science, Infection and pandemics, United States, Hong Kong, #preprint, #refines, #item, #source-2026-10, #score-52

Two cohorts, HIVE in Michigan and EPI-HK in Hong Kong, measured influenza antibody titres from 2020 to 2023\. Sera came from 57 HIVE participants (173 samples) and 60 EPI-HK participants (259 samples), none infected or vaccinated. Haemagglutination inhibition and microneutralisation assays against vaccine strains gave two-year fold changes, adjusted for age and baseline titre. In HIVE, H1N1 titres fell: A/Brisbane 0.70, A/Idaho 0.40, A/Michigan 0.43; H3N2 and B changed little. In EPI-HK, H1N1 varied in direction, while A/Cambodia fell to 0.44 and A/Singapore to 0.48\. Numbers were small and limited to uninfected, unvaccinated participants, so results may not generalise.

*Why it is interesting: Antibody titres did not decline uniformly during a period of reduced influenza transmission. The strain-specific pattern informs how immunity gaps are assessed after suppressed circulation.*

Source

[medRxiv, 17 October 2026](https://doi.org/10.1101/2025.05.26.25328346?ref=coios.me)

Paper

A prospective, comparative cohort analysis of influenza antibody waning in Michigan and Hong Kong during periods of low influenza circulation

Authors

Yang Y, Smith M, Ho F, Truscon R, Leung NHL, Touyon L et al.

DOI

10.1101/2025.05.26.25328346

Type

Preprint

Design

Two prospective serological cohorts (HIVE Michigan, n=57, 173 sera; EPI-HK Hong Kong, n=60, 259 sera), 2020-2023, HAI and microneutralisation, power-law fold-change models

Verdict

Refines prior evidence

Driver

[Infection and pandemics](https://www.coios.me/d-infectious-disease/)