Hand, foot and mouth disease

Hand, foot and mouth disease is a common viral infection of young children, although anyone can catch it. It is caused by a group of viruses and has nothing to do with the foot and mouth disease that affects cattle.

It is a mild illness in almost every child. Symptoms start about three to five days after catching the virus and are over in about 7 to 10 days. It spreads quickly in creches and playgroups, so several children in a class often get it at once.

The illness usually begins with a fever, a sore throat, a general feeling of being unwell and loss of appetite. A child may dribble more than usual, or refuse warm drinks.

A day or two later, small red spots appear on the tongue and inside the mouth. They blister and can be very sore, which is what makes eating and drinking difficult. A rash of flat or slightly raised red spots, sometimes with blisters, then appears on the palms and soles, and often on the buttocks, legs, arms and around the nappy area. The rash does not usually itch. On darker skin the spots can be harder to see and may look brown or grey.

See a doctor within a few days if the child is under six months old, if the fever lasts more than three days, if the symptoms are no better after 10 days, if the mouth ulcers are keeping the child from eating and drinking, if the child's immune system is weakened, or if you are pregnant and have been in close contact.

The illness is caused by a group of viruses that live in the gut and the throat. Children under five are most often affected, partly because they are still learning about handwashing and partly because they share toys, cups and close space.

The virus passes from one child to another through droplets from coughs and sneezes, through the fluid inside the blisters, through saliva on shared cups and toys, and through stool on hands after the toilet or a nappy change. A child is most infectious in the first week, but the virus can stay in the stool for some weeks after the child feels well.

• Being under five years old
• Attending a creche, playgroup or nursery
• A brother, sister or classmate with the illness
• Sharing cups, spoons, bottles and toys
• Crowded living or play spaces
• A weakened immune system, which can make the illness more severe

Complications are uncommon, and most children recover completely.

• Dehydration, the commonest problem, because the mouth ulcers make drinking painful
• Loss of fingernails or toenails some weeks later, which grow back on their own
• Viral meningitis, uncommon, which may need hospital care
• Inflammation of the brain or weakness of a limb, which are very rare
• Illness in a newborn if the mother catches it close to delivery, which is usually mild

• Washing hands with soap after the toilet, after nappy changes and before food
• Teaching children to cough and sneeze into a tissue or the elbow
• Cleaning toys, door handles and surfaces that are touched often
• Not sharing cups, bottles, spoons, towels or bedding
• Keeping a child at home while they are unwell
• Washing soiled clothes and bedding separately on a hot wash
• Avoiding close contact with an affected child during pregnancy

The diagnosis is made by looking. The combination of fever, sore mouth ulcers and a rash on the palms and soles in a young child is distinctive, and the doctor will also ask whether the illness is going round the creche or school.

Tests are rarely needed. A swab from the throat or a stool sample can identify the virus, and may be used in an outbreak or when a child is unusually unwell, but they do not change the treatment.

There is no medicine that clears the virus, and none is needed. The illness settles on its own, and everything done is to keep the child comfortable and drinking.

Cool drinks such as water or milk are soothing, while fruit juice and fizzy drinks sting the ulcers. Soft, cool food such as curd, custard and mashed rice is easier than hot, salty or spicy food. Paracetamol or ibuprofen can be given for fever and for the pain of the ulcers, at the dose advised for the child's age and weight. Aspirin should not be given to children. A pharmacist can suggest a mouth gel, spray or mouthwash suitable for the child's age.

Antibiotics do not work against this virus. A child who becomes dehydrated because the mouth is too sore to drink may need fluids in hospital, which is the main reason a child with this illness is admitted.