What is the period when hand, foot, and mouth disease is most contagious?

There is generally no standard definition of the "strongest" contagious period, but typically, hand, foot, and mouth disease (HFMD) is most contagious within the first week after symptom onset. Specific details are as follows:

HFMD is caused by intestinal viral infections and is highly contagious. The main transmission routes include close contact, foodborne transmission, and droplet transmission. Early symptoms may include fatigue, reduced appetite, low-grade fever, blisters on the oral mucosa, and rashes or blisters on the hands, feet, and other areas. In a small number of cases, neurological complications may occur, presenting as headache, vomiting, muscle weakness, and similar symptoms. HFMD primarily affects children under 5 years old. The disease is infectious about 3–5 days before symptoms appear, and during the first week after onset, viral replication in the body is particularly active, making the patient highly contagious. It's important to take proper isolation measures to prevent spreading the infection to others.

The disease remains somewhat contagious from the onset of symptoms until the rashes have ruptured and crusted over, with recovery usually occurring within about one week. It is recommended to practice self-isolation in daily life, wash hands frequently, properly disinfect personal items, and avoid cross-infection. Generally, children should avoid contact with healthy peers for at least two weeks to resume normal daily activities and schooling.

If patients experience discomfort due to HFMD, they should seek medical attention promptly and receive standardized treatment under a doctor’s guidance, which can aid in recovery.