Quick answer. Measles is one of the most contagious viral infections, causing fever, cough, runny nose, red eyes and a spreading rash. It can lead to serious complications, is preventable with the MMR vaccine, and is a notifiable disease that doctors in Singapore must report to MOH.
Measles is a highly contagious viral illness that spreads through the air and can affect anyone who is not immune. It typically begins like a heavy cold, with fever, cough, runny nose and red, watery eyes, followed a few days later by a distinctive rash. While many people recover, measles is not a trivial childhood illness, it can cause pneumonia, brain inflammation and other serious complications, particularly in young children, pregnant women and people with weakened immune systems.
In Singapore, measles is uncommon because of high MMR vaccination coverage, but imported cases and local clusters still occur, so it remains important to recognise. This guide explains what measles is, its symptoms, how it spreads, how it is diagnosed and how it is managed, plus when to seek urgent care. Because measles is a notifiable disease, a suspected or confirmed case will be reported to the Ministry of Health.
At a glance
| Stage | What happens | When to worry |
|---|---|---|
| Early (1-4 days) | Fever, cough, runny nose, red watery eyes | Very high fever or breathing difficulty |
| Koplik spots | Tiny white spots inside the cheeks before the rash | Child becoming very drowsy or unresponsive |
| Rash | Red blotchy rash starts on the face and spreads downward | Signs of dehydration or laboured breathing |
| Recovery | Rash fades over several days, cough may linger | Fever returning after improving (possible complication) |
| Contagious period | From about 4 days before to 4 days after the rash | Exposure of unvaccinated infants or pregnant contacts |
What is measles?
Measles is an infection caused by the measles virus, a paramyxovirus that is among the most contagious diseases known. It spreads through the air and can remain infectious in a room for some time after an infected person has left. Without immunity, the great majority of exposed people will catch it.
It most commonly affects children, but unvaccinated adults are equally susceptible. In Singapore, the National Childhood Immunisation Schedule has kept measles rare, yet it can still appear through travellers or unvaccinated individuals, which is why maintaining high vaccination coverage matters for protecting the wider community, especially babies too young to be vaccinated.
Symptoms & signs
Symptoms usually start about ten to fourteen days after exposure. The illness tends to follow a recognisable pattern:
- Fever, often high, with tiredness
- Cough, runny nose and a sore throat
- Red, watery eyes and sensitivity to light
- Tiny white spots inside the cheeks (Koplik spots) a day or two before the rash
- A red, blotchy rash that begins on the face and behind the ears, then spreads down the body
The rash usually appears a few days after the first cold-like symptoms and fades over about a week.
How it spreads & who is at risk
Measles spreads through respiratory droplets and airborne particles when an infected person coughs, sneezes or breathes. It is so contagious that being in the same room as an infected person can be enough to catch it if you are not immune. People are infectious from about four days before the rash appears to about four days after, often before they realise they have measles.
The main risk factor is lack of immunity from vaccination or previous infection. Those at greatest risk of severe disease and complications include infants too young to be vaccinated, pregnant women, and people with weakened immune systems. Travel to areas where measles is circulating also increases risk for the unvaccinated.
How it is diagnosed
A doctor may suspect measles from the combination of fever, cough, red eyes, runny nose and the characteristic rash, especially if Koplik spots are seen or there has been a known exposure. To confirm the diagnosis, a doctor may arrange:
- A blood test for measles antibodies
- A throat or nose swab, or a urine sample, to detect the virus (PCR testing)
If measles is suspected, it is important to inform the clinic in advance where possible, so that you can be seen in a way that limits exposure to others. As a notifiable disease, suspected and confirmed measles must be reported to MOH for contact tracing and outbreak control.
Treatment & prevention
There is no specific cure for measles, so care is supportive while the immune system fights the virus. This usually includes:
- Rest and plenty of fluids to prevent dehydration
- Paracetamol for fever and discomfort, as advised by a doctor
- Keeping the room comfortable and dim if the eyes are sensitive to light
- Treatment of any complications, such as antibiotics for a secondary bacterial infection, if they develop
The best protection is the MMR vaccine, given routinely to children in Singapore and available to non-immune adults. Vaccination not only protects the individual but also shields vulnerable people who cannot be vaccinated. Staying away from others while infectious is essential to prevent spread.
When to see a doctor & which specialist
See a doctor if you or your child develops a high fever with cough, red eyes and a spreading rash, particularly if vaccination is incomplete or there has been a possible exposure. Call ahead so the clinic can reduce the risk to others. Seek urgent care, and go to A&E or call 995, if there are any warning signs of serious complications:
- Difficulty breathing or fast, laboured breathing
- Signs of dehydration, such as very little urine, no tears or a dry mouth
- Drowsiness, confusion, a severe headache or a fit
- A stiff neck or persistent vomiting
- Fever that returns after the child seemed to be recovering
For assessment and to arrange testing and MOH notification, start with a family doctor. You can find one through our directory of GP clinics in Singapore.
Related guides
- Best Paediatric Clinics in Singapore — our editorial shortlist
- paediatric clinics directory
- Mumps
- Liver transplant
- Ganglion cyst
- Lipoma
- Molluscum contagiosum
Sources
Find a specialist
Prefer a named doctor? See our independent, sub-specialty-grouped directory of paediatricians in Singapore.
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