Elsevier

EBioMedicine

Volume 68, June 2021, 103398
EBioMedicine

Research paper
Kinetics of the neutralising antibody response in patients with hand, foot, and mouth disease caused by EV-A71: A longitudinal cohort study in Zhengzhou during 2017-2019

https://doi.org/10.1016/j.ebiom.2021.103398Get rights and content
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Abstract

Background

Hand, foot, and mouth disease (HFMD) caused by enterovirus A71 (EV-A71) poses a serious threat to children's health. Kinetics of the neutralising antibody (NAb) response in EV-A71 infected HFMD patients remains unclear. The ideal sampling time of paired serum samples for serological diagnosis of EV-A71 infection is not well defined.

Methods

HFMD inpatients admitted to Henan Children's Hospital between February 15, 2017 and February 15, 2018 were enrolled. Serial serum samples collected during hospitalisation and up to 1.5 years after discharge were tested for NAb against EV-A71. Random intercept modelling with B-spline was conducted to characterize the kinetics of the EV-A71 NAb response over time after illness onset.

Findings

A total of 524 serum samples from 264 EV-A71 RNA positive HFMD inpatients were collected. NAb titres of EV-A71 infected patients were estimated to increase from 40 (95% CI: 9-180) at the day of onset to the peak of 2417 (95% CI: 1859-3143) at day 13, then remained above 1240 until 26 months. For serological diagnosis of EV-A71 infection, if at least a 4-fold rise in titre was used as the criteria, the acute phase serum should be collected at 0-4 days, the corresponding convalescent serum should be collected 14.9 days (95% CI: 9.1-23.8) after illness onset.

Interpretation

EV-A71 infection induced a strong and persistent humoral immune response in HFMD patients. The findings provide a scientific support for determining the collection time of paired serum samples for serological diagnosis of EV-A71 infected HFMD patients.

Funding

National Science Fund for Distinguished Young Scholars

Keywords

HFMD
EV-A71
Neutralising antibody
Acute phase
Convalescent phase

Cited by (0)

Contributed equally to this work.

Joint senior authors with equal contribution