Medical Conditions

Coxsackie Virus (Hand, Foot, and Mouth Disease) in Baby

Medically reviewed by Dr. Michael Okonkwo, MD, FAAP · Board-Certified Neonatologist

Content reviewed against published AAP, CDC, NIH guidelines

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If your baby has been diagnosed with or you suspect coxsackie virus (hand, foot, and mouth disease) in baby, here is what the evidence says.

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.

Key takeaways

  • 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.
  • Usually normal when: Fever lasting 2-3 days
  • Call your doctor if: Signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes
“Fever itself is not an illness — rather, it is a sign or symptom that the body is fighting an infection. Fever stimulates certain defenses, such as the white blood cells, which attack and destroy invading bacteria.”
— Fever and Your Child, American Academy of Pediatrics (AAP)

Parents everywhere have the same worry. You are doing the right thing by looking into it.

What Parents Should Know

According to AAP, CDC, NIH guidelines, 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. At 0-12 months, 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. It is generally considered normal when fever lasting 2-3 days. However, you should contact your pediatrician promptly if signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes.

Sources: [1], [2], [3]

Normal vs. Concerning

Usually Normal
Worth Discussing
Fever lasting 2-3 days
Signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes
Mouth sores that are painful but improving over 5-7 days
High fever above 104 degrees F (40 degrees C)
A blister-like rash on hands, feet, and/or buttocks
Your child is lethargic, not just tired
Reduced appetite for a few days due to mouth soreness
A newborn (under 1 month) with symptoms of HFMD

When to Seek Immediate Care

  • 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)

By Age

What to expect by age

0-12 months

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.

1-3 years

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 to Tell Your Pediatrician

  • Describe when you first noticed coxsackie virus (hand, foot, and mouth disease) in baby and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if your child is not drinking enough fluids due to mouth sore pain.
  • Mention if the fever lasts more than 3 days.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

What Should You Do?

When to take action

Probably normal when...
  • 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)
Mention at your next visit when...
  • 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
Act now when...
  • 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)

What You Can Do at Home

  • Keep track of when you notice coxsackie virus (hand, foot, and mouth disease) in baby — noting the time of day, duration, and any triggers can help your pediatrician.
  • Remember that fever lasting 2-3 days — this is generally within the range of normal.
  • At 0-12 months, focus on observation rather than intervention unless your pediatrician advises otherwise.
  • Follow any care instructions from your pediatrician. Keep a written log of symptoms to bring to appointments.
  • While monitoring at home, seek immediate care if signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes.

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.

baby mouth sores

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Guide

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Frequently asked questions

Is coxsackie virus (hand, foot, and mouth disease) in baby normal?
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.
When should I call the doctor about coxsackie virus (hand, foot, and mouth disease) in baby?
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
When is coxsackie virus (hand, foot, and mouth disease) in baby normal?
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
What causes coxsackie virus (hand, foot, and mouth disease) in baby?
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. Common explanations include: Fever lasting 2-3 days. Mouth sores that are painful but improving over 5-7 days.
What should I mention to my pediatrician about coxsackie virus (hand, foot, and mouth disease) in baby?
You should mention coxsackie virus (hand, foot, and mouth disease) in baby at your next visit if: 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.
Is coxsackie virus (hand, foot, and mouth disease) in baby normal at 0-12 months?
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.
Is coxsackie virus (hand, foot, and mouth disease) in baby normal at 1-3 years?
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.
Should I go to the ER for coxsackie virus (hand, foot, and mouth disease) in baby?
Seek emergency care if signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes, or if high fever above 104 degrees F (40 degrees C). When in doubt, call your pediatrician's after-hours line for guidance.
Does coxsackie virus (hand, foot, and mouth disease) in baby go away on its own?
In many cases, coxsackie virus (hand, foot, and mouth disease) in baby resolves on its own, especially when fever lasting 2-3 days.
AAPCDCNIH

References

  1. [1]American Academy of Pediatrics. Hand, Foot, and Mouth Disease. HealthyChildren.org. AAP
  2. [2]Centers for Disease Control and Prevention. Hand, Foot, and Mouth Disease. CDC
  3. [3]National Library of Medicine. Coxsackievirus. StatPearls. NIH

Doctor Visit Checklist

Bring this checklist to your next pediatrician visit to discuss Coxsackie Virus (Hand, Foot, and Mouth Disease) in Baby.

Things to mention

  • Describe when you first noticed coxsackie virus (hand, foot, and mouth disease) in baby and how it has changed over time.
  • Note your baby's current age and which age-specific patterns you are seeing.
  • Mention if your child is not drinking enough fluids due to mouth sore pain.
  • Mention if the fever lasts more than 3 days.
  • Let your doctor know if you have noticed any related concerns, such as changes in feeding, sleep, or movement patterns.
  • Bring a list of any questions or observations you want to discuss at the appointment.

Observations to share

  • 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

Urgent signs to report immediately

  • 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

My notes

From ismybabyalright.com — free, evidence-based baby health guides

All content follows our editorial policy and is reviewed against published clinical guidelines.

2,705 evidence-based guides6 authoritative medical sources5 medical advisory board members

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Bottom line

Most cases of coxsackie virus (hand, foot, and mouth disease) in baby are normal. Talk to your pediatrician if signs of dehydration: no wet diaper for 6+ hours, no tears when crying, dry mouth, sunken eyes.

Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.

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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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