The Ministry of Health reports that since the beginning of 2026, the country has recorded approximately 26,000 cases of hand-foot-and-mouth disease and 8 deaths. In March alone, the average weekly number of cases increased compared to the previous month. Many test samples have identified the circulating Enterovirus 71 (EV71) strain, a common cause of severe hand-foot-and-mouth disease, though its symptoms are often atypical. Given this situation, doctor Huynh Tran An Khuong, a medical specialist at VNVC Immunization System, highlights five key points parents should be aware of:

Subtle disease symptoms

According to doctor Khuong, children with hand-foot-and-mouth disease typically experience fever, loss of appetite, and sore throat, followed by mouth sores, and rashes or blisters on their hands, feet, and knees. With EV71, skin lesions may be subtle or appear in less obvious areas such as: between fingers and toes, on the buttocks, or genitals. These manifestations are easily mistaken for teething fever or pharyngitis, leading parents to be complacent, and children to rapidly worsen.

The foot of a child with severe hand-foot-and-mouth disease, treated in the ICU at Children's Hospital 1. Photo: Dieu Thuan

Rapid worsening

Most children recover within 7-10 days, but the EV71 virus can cause the disease to progress from mild to severe in just a few hours, leading to serious complications such as: brainstem encephalitis, encephalitis, autonomic nervous system dysfunction, and cardiovascular and respiratory issues. If a child's condition rapidly worsens, there is a risk of death within 24 hours if not treated promptly.

"The most dangerous stage is when the virus begins to affect the brain," doctor Khuong stated, adding that brainstem encephalitis is a common complication, affecting 58% of children with severe cases.

Subsequently, the virus can affect the central nervous system, leading to autonomic nervous system dysfunction. During this stage, children typically exhibit four signs: startling, vomiting, tremors, and motor incoordination. If a child startles more than two times within 30 minutes, the risk of severe neurological complications is very high. Therefore, doctor Khuong advises families to hospitalize their child immediately if they observe startling, accompanied by difficulty breathing, lethargy, limb weakness, vomiting, or limb tremors.

Multiple reinfections are possible

The EV71 strain has various sub-genotypes such as: B3, B4, B5, C1, C4, and C5. Children have immature immune systems; even after being infected with one strain, they can be reinfected with other strains or sub-genotypes of the virus multiple times. The period for reinfection, calculated from the first illness, ranges from 12-36 months or shorter.

Fever symptoms require attention

To prevent rapid worsening due to EV71 potentially masking skin symptoms, doctor Khuong advises families to pay close attention to a child's fever. This is a warning sign that the virus has entered the nervous system and is also the first symptom at disease onset.

If a child has a continuous high fever above 39°C, does not respond to common fever-reducing medication, lasts over 48 hours, or shows no improvement, the risk of dangerous complications such as: encephalitis, meningitis, or myocarditis is very high. Therefore, parents should take their child for a medical examination immediately when fever occurs. They should not self-medicate the child with fever reducers or hesitate due to concerns about secondary infections.

Young children receiving disease prevention vaccine at VNVC Immunization System. Photo: Dieu Thuan

Prevention methods

To prevent hand-foot-and-mouth disease, families should clean their homes and children's toys, ensure children eat cooked food and drink boiled water, avoid sharing personal items, and isolate sick children. Currently, there is no specific treatment for the disease. However, the Ministry of Health has licensed an EV71 virus prevention vaccine for children aged two months to under six years. This vaccine offers nearly 97% protective efficacy, preventing severe complications and reinfection. The VNVC Immunization System will soon introduce and deploy this vaccine in the country.

Phuc An