Can Children Get Hand-Foot-and-Mouth Disease More Than Once?
Yes, children can absolutely get hand-foot-and-mouth disease (HFMD) multiple times because there is no cross-protection between the different enterovirus subtypes that cause the disease.
Why Reinfection Occurs
The fundamental reason children experience HFMD repeatedly is that the disease is caused by multiple different enteroviruses—primarily EV-A71, Coxsackievirus A16, and CV-A6 1. Immunity to one enterovirus subtype does not protect against infection with other subtypes, making reinfection not only possible but relatively common 2.
How Common Is Reinfection?
Recent large-scale studies provide clear data on reinfection rates:
- In Qingdao, China, the reinfection rate was 2.60% among 78,422 HFMD cases over 9 years 2
- In Quzhou, China, the reinfection rate was 4.94% among 79,841 cases over 16 years 3
- In Fujian province, 3.15% of 82,949 children experienced recurrent HFMD 4
Most children who get reinfected experience it twice (96-97% of reinfection cases), though some children can get it three, four, or even five times 4, 3.
Time Between Infections
The median interval between first and second infections is approximately 12-13 months 2. Interestingly, the time between subsequent infections tends to shorten—dropping to about 10 months between the second and third infection 3.
Which Children Are at Highest Risk for Reinfection?
Multiple studies consistently identify these risk factors:
- Age under 3 years (especially those first infected before age 2, with risk increasing 2.73-4.39 times) 4, 3
- Male gender (1.34 times higher risk than girls) 2, 4
- Children attending daycare or maternal/child care settings (1.64 times increased risk) 4
- Initial infection with EV71 (1.83 times higher reinfection risk) 2
- Severe initial cases requiring hospitalization 2
- Living in areas with high HFMD prevalence (>4% morbidity areas show 2.15 times increased risk) 4
Clinical Implications
A critical caveat: reinfection can sometimes cause more severe symptoms than the initial infection 4. In rare cases, children can be reinfected with the same serotype (such as EV71 twice), which may lead to more severe manifestations 4.
The seasonal pattern of reinfection mirrors primary infection, with peaks typically occurring from April to August, particularly June-August 2, 3.
Prevention Strategy
Given the high reinfection risk, sustained preventive measures are essential even after a child has had HFMD once:
- Rigorous hand hygiene practices
- Environmental sanitation
- Limiting exposure during peak seasons
- Consider EV-A71 vaccination where available (shows >90% efficacy against severe EV-A71 HFMD) 5
The key message for parents and clinicians: having HFMD once does not provide comprehensive immunity, and children—especially young boys under 3 years attending daycare—require ongoing vigilance and preventive measures.