If your child is starting crèche or pre-school, get ready for the onslaught of childhood bugs. A March 2026 study involving researchers from University College London found young children will experience around 12–15 respiratory infections, two gastrointestinal illnesses and one or two rash-causing infections in the first year alone.

Ballina-based GP and infection control clinical lead with the Irish College of General Practitioners (ICGP) Scott Walkin says frequent bugs in the first year are because your child is meeting with lots of others for the first time. “Picking up frequent bugs is a rite of passage – it’s how our immune system develops.”

Walkin says the silver lining is that next time the child meets this infection, they’ll have immunity, and they either won’t get it – or they’ll be less ill.

Here are six common childhood bugs to know about:

Coughs and colds

Almost inevitable, says Walkin. “Young children commonly have six or more each year. Most are mild, viral and self-limiting.”

You’ll notice:

sore throat, sneezing, blocked/runny nose, cough
fever, tiredness, irritability or reduced appetite

“Most sore throats improve within seven days. Head colds can take longer – in particular a cough can take up to three weeks to settle.”

What to do:

Age- and weight-appropriate paracetamol or ibuprofen for pain or fever.
Saline nasal drops or spray may help a blocked nose.
Warm lemon and honey drink may soothe a cough in children over one.
Normal drinks and food as tolerated.
No cough and cold remedies for under-sixes unless GP or pharmacist advises.
Keep child home from crèche or pre-school if too unwell to participate normally or if temperature’s 38°C or above.
Consider influenza with fever, marked tiredness, aches, headache, sore throat and cough. HSE recommends the free nasal spray flu vaccine each year for two to 17-year-old children.

Tummy bugs

Dr Scott Walkin, infection control clinical lead with the ICGP. Dr Scott Walkin, infection control clinical lead with the ICGP. 

Walkin says this usually means viral gastroenteritis, causing vomiting and/or diarrhoea. “It spreads very easily through hands, shared surfaces, food and contact with vomit or faeces. Most children recover at home, but they can quickly become dehydrated. The main treatment is replacing fluid and watching carefully for dehydration.”

You’ll notice:

sudden vomiting, watery diarrhoea
tummy cramps, nausea, reduced appetite, tiredness
sometimes fever, headache, muscle aches.
Vomiting usually lasts one-to-two days. Diarrhoea often starts to improve within three days but can last up to seven.

What to do:

Offer small, frequent sips of liquid. Oral rehydration solution can replace lost water, salts and sugar – pharmacist can recommend suitable product.
Once able, offer child’s usual foods.
Avoid fruit juice and fizzy drinks while diarrhoea is active.
Do not give young children medicines to stop diarrhoea unless doctor specifically advises.
Watch for dehydration – Much less urine, dark yellow urine; dry mouth, few or no tears, sunken eyes; unusual sleepiness, reduced responsiveness, pallor or low energy; unable to keep fluids down.
No attending school, crèche or childcare until at least 48 hours have passed since the last vomiting or diarrhoea episode.

Conjunctivitis

Inflammation of the covering of the white of the eye and the inner eyelids may be caused by virus, bacteria or allergy.

“It’s common in preschool children, usually mild and often settles without antibiotic treatment,” comments Walkin.

“Most infectious conjunctivitis improves within five-to-seven days, though symptoms can last up to two weeks.”

You’ll see:

one or both eyes red or bloodshot – if whites of eyes aren’t red, it’s not conjunctivitis
watery eyes, grittiness, irritation, mild soreness
yellow-white sticky discharge, lashes stuck together on waking
mild eyelid swelling
cold or sore-throat symptoms (viral conjunctivitis)
itching and watery eyes (allergic conjunctivitis)
pain, light sensitivity, altered vision aren’t typical and need prompt assessment.

What to do:

Wash hands before and after cleaning or touching eye.
Gently remove discharge using clean cotton pad moistened with cooled boiled water.
Wipe from inner to outer corner, using separate pad for each eye.
A clean, cold flannel held over closed eye for a few minutes may soothe irritation.
Discourage rubbing – no sharing towels, pillows, face cloths.
Conjunctivitis alone isn’t a reason to exclude child from pre-school if otherwise well.

Hand, foot and mouth disease

Common, highly contagious and viral it usually affects under-10s. “It’s generally mild and settles by itself within seven-to-10 days. In most children it’s managed with comfort, fluids and observation,” says Walkin.

You’ll see:

sore throat, temperature above 38C, reduced appetite, general unwellness – at first.
painful mouth ulcers a few days later – drinking may be difficult
raised red spots (sometimes blisters) on hands and feet, occasionally also on buttocks/groin
pain or itching from rash.

What to do:

Age-appropriate paracetamol or ibuprofen for pain or fever.
Regular drinks – small sips through straw may be easier.
Soft, cool foods – yogurt, smoothies, mashed foods, ice cream.
No hot, spicy, acidic or citrus foods/drinks – they sting mouth ulcers.
Ask pharmacist about child-appropriate mouth-ulcer gels, sprays or mouthwashes.
Keep blisters clean with lukewarm soap and water – pat dry, no popping them.
Keep child home while they feel unwell.

Chickenpox

“A very contagious viral infection, it’s usually mild in healthy children and gets better without specific treatment,” says Dublin-based GP and ICGP immunisation clinical lead Patrick Kelly. “Practical priorities are itch relief, hydration, preventing skin infection and protecting vulnerable contacts.”

You’ll see:

itchy rash that may start on head, neck or trunk but can appear anywhere, including inside the mouth.
spots that become fluid-filled blisters and then crust over.
new crops of spots for three-to-five days
temperature above 38C, aches, poor appetite, general unwellness.
blisters usually crust after one-to-two days. Scabs generally fall off after one-to-two weeks.

What to do:

Use age-appropriate paracetamol for fever, pain or discomfort.
No ibuprofen – it may increase risk of serious skin infection.
Keep fingernails short and clean – socks on hands at night may reduce scratching.
Use lukewarm baths, pat skin dry, dress child in loose cotton clothing.
Treatments for itch include oatmeal baths, calamine lotion – antihistamine if troublesome.
Regular drinks – ice pops may help with painful mouth spots.
Keep child away from school/childcare until every spot has crusted over and is dry – usually five-to-seven days after rash first appears. A child’s infectious from about two days before rash appears until all lesions are crusted and dry.

“The varicella vaccine is part of the HSE childhood vaccination schedule for children born [since] 1 October 2024. First dose is given at 12 months, the second in junior infants,” says Kelly.

Fever

Fever – temperature of 38C or above – is common in young children and almost always due to infection. West Cork-based GP and ICGP paediatric sepsis lead Andrea Fitzgerald says height of the fever on its own isn’t a useful guide to how serious an illness is.

“A high fever can occur with a minor infection – and a child who’s seriously unwell may have no fever at all. How your child looks and behaves, whether they’re breathing normally, whether they’re drinking and passing urine, and whether they seem better or worse in themselves are more important than how high their temperature is.”

But Fitzgerald says the height of fever does matter in some situations: Babies under three months with temperature of 38C or above, and three- to six-month-olds with temperature of 39C or above require medical assessment. “Low temperature – below 36C – can also be a sign of serious illness.”

What to do:

Use digital thermometer in the armpit for babies under four weeks. For older children, use armpit or infrared in-ear thermometer.
Most children with fever can be cared for at home.
Offer drinks regularly – and food if wanted.
Dress child comfortably – no over-wrapping or deliberately under-dressing them.
No cold baths or cold sponging – can make feverish children very uncomfortable and shivering may actually raise temperature.
Use paracetamol or ibuprofen if child’s uncomfortable, distressed or in pain – no need for medicine simply to lower a high temperature.
Check on child regularly, including at night – no waking them simply to take their temperature.

Fitzgerald advises seeking medical advice if something about your child’s illness is worrying you. “This includes if they seem unusually unwell or aren’t behaving as you’d expect, are breathing unusually fast or working hard to breathe, aren’t drinking or can’t keep fluids down, or haven’t passed urine for 12 hours – or have pain that doesn’t settle with regular pain relief.

“If your child has been assessed but you’re still worried, seek advice again, particularly if they seem to be becoming more unwell.”