Coxsackie Virus (Hand, Foot, and Mouth Disease) in Baby
The short answer
Coxsackie virus is the most common cause of hand, foot, and mouth disease (HFMD) in children. It causes fever, painful mouth sores (small ulcers on the tongue, gums, and inside of cheeks), and a blister-like rash on the hands, feet, and sometimes buttocks. It is extremely common in children under 5 and spreads easily in daycare settings. There is no specific treatment - it is a viral illness that resolves on its own within 7-10 days. The main concern is ensuring your child stays hydrated, as the mouth sores can make eating and drinking painful.
By Age
What to expect by age
Babies with coxsackie virus often present with fever, irritability, drooling (from mouth sores), and refusal to feed. The rash may appear as small blisters on the palms, soles, and buttocks. Babies are at higher risk for dehydration because the mouth sores make feeding painful. Offer small, frequent feeds of breast milk, formula, or an electrolyte solution. Cold liquids and popsicles (for babies eating solids) can help soothe the pain. Avoid acidic or salty foods. The illness is most contagious in the first week, especially while the child has a fever.
Hand, foot, and mouth disease is very common in toddlers, especially those in daycare. After a 3-5 day incubation period, the illness starts with fever, sore throat, and reduced appetite, followed by mouth sores and the characteristic rash. The rash may also appear on the knees, elbows, and buttocks. Treatment is supportive: acetaminophen or ibuprofen for pain and fever, cold fluids and popsicles for mouth soreness, and avoiding spicy or acidic foods. Blisters are not typically itchy. Peeling of finger and toenails (onychomadesis) can occur 4-8 weeks later and is harmless. Children can return to daycare after the fever resolves, though they remain mildly contagious for weeks through stool.
What Should You Do?
When to take action
- Fever lasting 2-3 days
- Mouth sores that are painful but improving over 5-7 days
- A blister-like rash on hands, feet, and/or buttocks
- Reduced appetite for a few days due to mouth soreness
- Nail peeling 4-8 weeks after the illness (harmless)
- Your child is not drinking enough fluids due to mouth sore pain
- The fever lasts more than 3 days
- You want to confirm the diagnosis
- Your child has had HFMD symptoms for more than 10 days without improvement
- Signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes
- High fever above 104 degrees F (40 degrees C)
- Your child is lethargic, not just tired
- A newborn (under 1 month) with symptoms of HFMD
- Severe headache with stiff neck and fever (rare complication - viral meningitis)
Sources
Related Resources
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Hand, Foot, and Mouth Disease in Babies
Hand, foot, and mouth disease (HFMD) is a very common viral illness in babies and toddlers, especially during summer and fall. It causes small blisters or sores in the mouth and a spotted rash on the hands and feet. While it can make your child uncomfortable for a few days, it is not dangerous and resolves on its own within 7-10 days.
Hand, Foot, and Mouth Disease - How Long Is It Contagious?
Hand, foot, and mouth disease (HFMD) is most contagious during the first week of illness, particularly in the first few days when the child has a fever. However, the virus can be shed in stool for weeks after symptoms resolve. The incubation period is 3-5 days (time from exposure to symptom onset). Most daycare and school policies allow children to return once the fever is gone for 24 hours and they can participate in activities. You cannot fully prevent spread once a child is symptomatic, as they were most contagious before anyone knew they were sick.
Herpetic Gingivostomatitis (Mouth Sores) in Babies
Herpetic gingivostomatitis is a common first-time infection with the herpes simplex virus (HSV-1) that causes painful sores on the gums, tongue, lips, and inside the cheeks. It is most common in children between 6 months and 5 years. While the sores look alarming and can make eating very painful for several days, the infection resolves on its own within 7-14 days. The main concern is keeping your child hydrated while their mouth is sore.
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