Childhood Illnesses & Immunisation
Common Childhood Illnesses
All children will experience illness at some point, and parents and carers need to recognise common conditions and their symptoms. Chickenpox is one of the most widespread childhood illnesses, spreading easily through airborne droplets or contact with the fluid in blisters. It begins with a fever and general malaise, followed within 1–2 days by an itchy rash that starts on the chest or back and spreads. The spots develop into blisters, then crust over. It is most contagious from two days before the rash appears until all spots have crusted. Children should be kept away from pregnant women and people with weakened immune systems. Most cases are mild and self-limiting; calamine lotion, cool baths and antihistamines ease itching.
Measles begins with fever, cough, runny nose and red, watery eyes (Koplik spots — white spots inside the cheeks — appear 2–3 days before the rash). The characteristic red blotchy rash spreads from the face down the body about four days into the illness. Measles is highly contagious and can lead to serious complications including ear infection, pneumonia and, rarely, encephalitis. It is a notifiable disease. Mumps causes swelling of the parotid (salivary) glands on one or both sides of the face, giving a 'hamster cheek' appearance, alongside fever and headache. It can lead to orchitis (testicular swelling) in post-pubertal males and, rarely, meningitis. Tonsillitis is an infection of the tonsils causing severe sore throat, pain on swallowing, fever, swollen cervical lymph nodes and white patches on the tonsils. It may be viral or bacterial; bacterial tonsillitis caused by Streptococcus requires antibiotics.
Meningitis warning signs in children include: a stiff neck, high fever, severe headache, photophobia (dislike of bright light), vomiting, confusion or drowsiness, and a non-blanching rash (spots that do not fade when a glass is pressed firmly against the skin). A non-blanching rash indicates possible septicaemia — call 999 immediately.
Meningitis and When to Seek Medical Help
Meningitis is one of the most serious childhood illnesses. Bacterial meningitis, most often caused by Neisseria meningitidis (meningococcal) or Streptococcus pneumoniae (pneumococcal), can progress from first symptoms to death within hours. The early signs mimic a flu-like illness, making it easy to miss. As the disease progresses, a distinctive non-blanching petechial or purpuric rash may appear — caused by bleeding under the skin from septicaemia. Parents should be advised to use the glass test (press a clear glass firmly over the rash: if it does not fade, it may be meningococcal disease) and call 999 immediately. Not all meningitis cases produce a rash; the combination of high fever, severe headache, stiff neck and photophobia should prompt urgent medical review regardless.
More generally, parents should seek medical attention if: a child has a high fever that does not respond to paracetamol or ibuprofen; the child is under three months with any fever; there is difficulty breathing; the child is unusually pale, limp or unresponsive; there is a rash or persistent vomiting; the illness is lasting longer than expected; or the parent's instinct tells them something is seriously wrong. Persistent or severe symptoms that do not match a known mild illness should always be checked by a healthcare professional.
The UK routine childhood immunisation schedule is free on the NHS and follows a nationally agreed timetable updated from January 2026. At 8 weeks: 6-in-1 vaccine (diphtheria, tetanus, whooping cough, polio, Hib, hepatitis B — first dose), Rotavirus (oral, first dose), MenB (first dose). At 12 weeks: 6-in-1 (second dose), MenB (second dose), Rotavirus (second dose). At 16 weeks: 6-in-1 (third dose), PCV (pneumococcal — first dose). At 1 year (12–13 months): MMRV vaccine (measles, mumps, rubella and varicella — first dose), PCV booster, MenB booster. Note: from January 2026 the MMRV vaccine replaces MMR; the Hib/MenC booster has been discontinued for children born from July 2024. At 18 months (new appointment, for children born on or after 1 July 2024): 6-in-1 (fourth dose), MMRV (second dose). From 2 years, annually each autumn: flu vaccine (nasal spray) — the programme continues through primary and secondary school age. At 3 years 4 months: 4-in-1 pre-school booster (diphtheria, tetanus, whooping cough, polio). At 12–13 years (girls and boys): HPV vaccine. At 14 years: 3-in-1 teenage booster (diphtheria, tetanus, polio), MenACWY. This schedule protects children from serious diseases at the age they are most vulnerable.
Herd immunity is achieved when a high enough proportion of the population (typically 90–95% for measles) is immune to a disease, so it cannot spread easily — protecting those who cannot be vaccinated, such as newborns and immunocompromised individuals. Maintaining high uptake rates is essential for herd immunity to hold.
The benefits of immunisation are well established: vaccines have eradicated smallpox globally and near-eliminated polio; MMR vaccination has dramatically reduced measles cases; herd immunity protects vulnerable groups who cannot be vaccinated. Immunisation is free on the NHS, saving families the cost of treatment for serious illness. However, some parents express concerns: minor side effects such as redness, swelling or a mild fever at the injection site are common and short-lived. More serious reactions (anaphylaxis) are extremely rare — approximately 1 in 1 million doses. A now-retracted 1998 study (Wakefield) claimed a link between the MMR vaccine and autism; this has been comprehensively discredited by large-scale studies involving millions of children, and Wakefield lost his medical licence. Despite this, vaccine hesitancy remains a public health challenge, and health visitors play a key role in providing evidence-based reassurance to parents with concerns.