How COVID-19 immunity changes over time in households in Hong Kong.
Patterns of SARS-CoV-2 Immunity at Household Level and Their Changes Over Time
This project will test how COVID-19 antibodies, vaccination, and past infections affect protection within Hong Kong households by collecting blood samples and short questionnaires over time.
Quick facts
| Study type | Observational |
|---|---|
| Enrollment | 1350 (estimated) |
| Sex | All |
| Sponsor | Chinese University of Hong Kong Academic / other |
| Locations | 1 site (Hong Kong, HONG KONG) |
| Trial ID | NCT05271669 on ClinicalTrials.gov |
What this trial studies
This observational cohort will follow about 900 people from households in Hong Kong and collect blood samples and questionnaires at three visits roughly 12–18 months apart. Blood will be tested for nucleocapsid and spike antibodies and a surrogate virus neutralisation test to infer prior infection and seroprotection levels. Questionnaires will record vaccination history, prior testing and infections, demographics, and precautionary behaviors. The study aims to describe how seroprotection and exposure risk change over time at the household level.
Who should consider this trial
Good fit: Ideal participants are people of any age who normally live in Hong Kong, can communicate in Chinese or English, and are willing to give blood and complete short questionnaires.
Not a fit: People who cannot give informed consent (such as some individuals with severe mental illness), prisoners, or those living outside Hong Kong are unlikely to receive direct benefit from this observational study.
Why it matters
Potential benefit: If successful, the findings could help target vaccination and household prevention strategies to reduce COVID-19 spread.
How similar studies have performed: Similar household serology cohorts elsewhere have successfully tracked infection and immunity trends, so this approach is well established.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * adults of age 18 or above, or children under the age of 18 with informed consent of the legal guardian * normally residing in Hong Kong * could communicate in spoken and written Chinese and/or English Exclusion Criteria: * individuals with mental illness * prisoners
Where this trial is running
Hong Kong, HONG KONG
- Shui Shan Lee — Hong Kong, Hong Kong, China (Recruiting)
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.