Abstract
Background
The adaptive immune responses of COVID-19 patients contributes to virus clearance, restoration of health and protection from re-infection. The patterns of and the associated characteristics with longitudinal neutralising antibody (NAb) response following SARS-CoV-2 infection are important in their potential association with the population risks of re-infection.
Methods
This is a longitudinal study with blood samples and clinical data collected in adults aged 18 or above following diagnosis of SARS-CoV-2 infection. NAb levels were measured by the SARS-CoV-2 surrogate virus neutralisation test (sVNT). Anonymous clinical and laboratory data were matched with surveillance data for each subject for enabling analyses and applying latent class mixed models for trajectory delineation. Logistic regression models were performed to compare the characteristics between the identified classes.
Results
In 2020–2021, 368 convalescent patients in Hong Kong are tested for NAb. Their seroconversion occur within 3 months in 97% symptomatic patients, the level of which are maintained at 97% after 9 months. The NAb trajectories of 200 symptomatic patients are classified by the initial response and subsequent trend into high-persistent and waning classes in latent class mixed models. High-persistent (15.5%) class patients are older and most have chronic illnesses. Waning class patients (84.5%) are largely young adults who are mildly symptomatic including 2 who serorevert after 10 months.
Conclusions
Characteristic sub-class variabilities in clinical pattern are noted especially among patients with waning NAb. The heterogeneity of the NAb trajectory patterns and their clinical association can be important for informing vaccination strategy to prevent re-infection.
【초록키워드】 SARS-COV-2 infection, Infection, risk, heterogeneity, Virus neutralisation, Health, Seroconversion, Symptomatic patients, Characteristics, symptomatic, neutralising antibody, Regression model, Patient, Re-infection, trajectory, Adaptive immune response, Hong Kong, convalescent patient, association, Analysis, COVID-19 patient, Vaccination strategy, Older, Clinical data, subject, virus clearance, sVNT, laboratory data, Variability, blood sample, chronic illnesses, surveillance data, Prevent, initial, Result, tested, performed, collected, subsequent, contribute, occur, were measured, diagnosis of SARS-CoV-2, latent class, symptomatic patient, the SARS-CoV-2, 【제목키워드】 SARS-CoV-2, neutralising antibody, convalescent COVID-19 patient,