Measles Symptoms Recognising the Signs and What Causes Them
Learn about measles symptoms, causes, stages, complications, and prevention. Understand the signs, risks, and how vaccination protects you and your family.
Written by Dr. M L Ezhilarasan
Reviewed by Dr. Dhankecha Mayank Dineshbhai MBBS
Last updated on 22nd Sep, 2025
Introduction
Measles, often remembered as a common childhood illness of the past, is a highly contagious and potentially serious viral infection. While often associated with a distinctive red rash, the journey of a measles infection begins long before the spots appear and involves a cascade of symptoms that can severely impact your health. Understanding what leads to these signs is crucial for early recognition, preventing spread, and seeking timely medical care. This article will demystify the measles virus, break down the timeline of its symptoms from initial exposure to recovery, and explain the science behind what causes this dramatic immune response. We'll also cover who is most at risk, the serious complications that can arise, and, most importantly, how to effectively protect yourself and your loved ones through vaccination.
What Exactly is Measles?
Understanding the Measles Virus
Measles, also known as rubeola, is not just a simple rash. It is an acute illness caused by a single-stranded RNA virus from the paramyxovirus family. This virus is uniquely adapted to humans and is one of the most contagious pathogens known. It attacks the respiratory system first but eventually spreads throughout the entire body, leading to the wide range of symptoms that characterise the disease. Before the widespread use of the vaccine, measles was a leading cause of childhood mortality worldwide, demonstrating that its impact is far more significant than the temporary discomfort of its visible signs.
The Primary Cause: How You Catch Measles
The Shockingly Contagious Nature of the Virus
The direct cause of any measles case is exposure to the measles virus. This exposure occurs through person-to-person contact via infected respiratory droplets. When an infected person coughs, sneezes, or even talks, these tiny droplets containing the virus are released into the air. The virus can remain active and contagious in the air or on infected surfaces for up to two hours. This is what makes measles so notoriously contagious; if one person has it, up to 90% of the non-immune people close to that person will also become infected. You can contract the virus by breathing the contaminated air or by touching a contaminated surface and then touching your eyes, nose, or mouth.
How Long Are You Contagious?
Understanding the contagion period is key to controlling outbreaks. An infected person can spread the measles virus to others from four days before the rash first appears to four days after it has erupted. This is a critical point because individuals are most contagious during the initial prodromal phase (with fever, cough, etc.), often before they even know they have measles. This ability to spread the disease before diagnosis makes public health containment efforts particularly challenging.
The Timeline of Measles Symptoms
The progression of measles is methodical and occurs in distinct clinical stages over a period of two to three weeks.
Stage 1: Incubation (Days 1-10/14)
After initial exposure, the virus enters the body through the respiratory tract. It begins to replicate silently in the back of the throat and lungs before spreading to the lymphatic system. This period, known as the incubation period, lasts an average of 10 to 14 days. During this time, there are no signs or symptoms of measles. The person feels perfectly fine, unaware that the infection is brewing.Consult a Specialist for Personalised Advice
Stage 2: Initial Signs and Prodromal Symptoms (Days 10-14)
The first signs of measles mark the beginning of the prodromal phase. This phase typically lasts 2 to 4 days before the rash appears and is often when the disease is most contagious.
High Fever
A high fever is often the very first sign, frequently spiking as high as 104°F (40°C). This fever is the body's systemic response to the rapidly multiplying virus.
The "Three C's": Cough, Coryza, Conjunctivitis
This classic triad of symptoms is a hallmark of the measles prodrome.
• Cough: A persistent, dry hacking cough develops.
• Coryza: This is the medical term for a severe runny nose.
• Conjunctivitis: Inflammation of the conjunctiva (the lining of the eyelid) leads to red, watery, and often painful eyes that may be sensitive to light (photophobia).
Malaise and Loss of Appetite
As with many systemic viral infections, individuals experience a profound feeling of being unwell (malaise), decreased energy, and a loss of appetite.
Stage 3: The Classic Measles Rash (Days 14+)
How the Rash Develops and Spreads
The rash presents as flat red spots that often blend together into larger blotchy patches. It usually begins on the face at the hairline and behind the ears. Over the next 24-48 hours, it slowly spreads downward, covering the neck, torso, arms, and legs, eventually reaching the feet. As it appears, the fever often spikes again, sometimes reaching its highest point. The rash itself is not itchy in the way a chickenpox rash is, and it can last for 5 to 6 days before fading in the same order it appeared, sometimes leaving a brownish discolouration and fine flaking of the skin.
Koplik's Spots: The Tell-Tale Sign Inside the Mouth
A definitive early sign of measles that appears 1-2 days before the skin rash are Koplik's spots. These are tiny white spots, like grains of salt surrounded by a red ring, found on the inside of the cheeks opposite the molars. They are a pathognomonic sign, meaning they are unique to measles infection, but they are transient and often disappear within a day of the skin rash forming, so they are frequently missed.
Stage 4: Recovery
Provided there are no complications, recovery from the rash and the illness begins after it has run its course. The cough may persist for a week or two. A key aspect of measles infection is that it suppresses the immune system for several weeks to months after recovery, making individuals more susceptible to other infections.
Who is Most at Risk of Severe Measles?
Vulnerable Groups and Risk Factors
While anyone who is not vaccinated can get measles, certain groups are far more likely to experience severe disease and complications:
• Young children: Especially those under the age of 5.
• Adults over the age of 20.
• Pregnant women: Measles can lead to pregnancy risks like premature birth, low birth weight, and even miscarriage.
• Individuals with compromised immune systems, such as those with leukaemia, HIV/AIDS, or those on immunosuppressive drugs, even if they were previously vaccinated.
The single biggest risk factor is not being vaccinated against measles. Travel to countries where measles is more common also increases the risk of exposure.
Serious Complications: Why Measles is Dangerous
About 30% of measles cases report one or more complications. These are what make measles a dangerous disease, not the initial symptoms themselves.
Common Complications like Ear Infections and Diarrhoea
Ear infections (otitis media) occur in about 1 in 10 children with measles and can lead to permanent hearing loss. Diarrhoea, which can be severe enough to require hospitalisation from dehydration, is reported in less than 1 in 10 cases.
Severe Complications: Pneumonia and Encephalitis
• Pneumonia is the most common cause of death from measles in young children. It can be caused by the measles virus itself or by a secondary bacterial infection that takes advantage of the weakened immune system.
• Encephalitis (inflammation of the brain) occurs in about 1 in 1,000 cases. It can lead to convulsions, deafness, and intellectual disability. It is fatal in about 15% of cases.
Long-Term Risk: Subacute Sclerosing Panencephalitis (SSPE)
SSPE is a rare but invariably fatal complication of measles. It is a progressive neurological disorder that causes brain inflammation and deterioration. It typically develops 7 to 10 years after a measles infection, even one that seemed typical at the time. It most commonly occurs in children who contracted measles before the age of two. There is no cure for SSPE.
How to Protect Yourself and Your Family
The MMR Vaccine: The Best Line of Defence
The Measles, Mumps, and Rubella (MMR) vaccine is extremely safe and effective at preventing measles. Two doses are about 97% effective at preventing the disease. The first dose is recommended for children at 12-15 months, and the second dose at 4-6 years. Adults who are unsure of their vaccination status should talk to their doctor about getting vaccinated. Vaccination doesn't just protect you; it protects those who cannot be vaccinated, like infants and the immunocompromised.
Herd Immunity and Its Importance
Herd immunity occurs when a high percentage of a community is immune to a disease (through vaccination), making its spread from person to person unlikely. This offers protection to individuals who are not immune. For a disease as contagious as measles, herd immunity requires about 95% of the population to be vaccinated. When vaccination rates drop, herd immunity breaks down, and outbreaks occur.
When to Seek Medical Attention Immediately
If you suspect you or your child has been exposed to measles or is developing symptoms, it is crucial to call your doctor immediately. Do not visit the clinic or hospital without calling first, as they will need to take special precautions to isolate you and prevent exposing other patients. If your condition does not improve after trying these methods, book a physical visit to a doctor with Apollo24|7 for further evaluation. Seek emergency care if you or your child experiences:
• Difficulty breathing
• Confusion or drowsiness
• Severe dehydration
• Seizures
Conclusion
Recognising what leads to the signs of measles is the first step in combating this resurgent disease. From the initial silent incubation to the dramatic onset of high fever, the "Three C's," and the spreading rash, the measles virus orchestrates a full-scale attack on the body. The real danger lies not in the initial symptoms but in the severe and sometimes fatal complications that can follow, such as pneumonia and encephalitis. The most critical insight is that all of this is preventable. The MMR vaccine stands as one of modern medicine's greatest public health achievements, offering safe and robust protection. Ensuring you and your family are up-to-date on vaccinations is the most powerful action you can take to stop the spread of measles and safeguard the health of your community. If you have any concerns about symptoms or vaccination status, consulting a healthcare professional is always the best course of action.
Consult a Specialist for Personalised Advice
Consult a Specialist for Personalised Advice
Dr Syed Mateen Pasha
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru
Dr. Syed Ismail Ali
General Practitioner
7 Years • MBBS
Hyderabad
Apollo 24|7 Clinic, Hyderabad
Dr. Johnson. S
General Practitioner
7 Years • MBBS MD(Preventive and social Medicine)
Pune
Apollo Clinic, Nigdi, Pune
Dr. Madhuri Sai Sreepada
General Practitioner
9 Years • MBBS
Hyderabad
BRIGHT SMILES MEDICARE & DENTAL CARE, Hyderabad
Dr. Karanam Kondalamma
General Practitioner
4 Years • MBBS
Hyderabad
KK Clinic, Hyderabad
Consult a Specialist for Personalised Advice
Dr Syed Mateen Pasha
General Physician
2 Years • MBBS
Bengaluru
PRESTIGE SHANTHINIKETAN - SOCIETY CLINIC, Bengaluru
Dr. Syed Ismail Ali
General Practitioner
7 Years • MBBS
Hyderabad
Apollo 24|7 Clinic, Hyderabad
Dr. Johnson. S
General Practitioner
7 Years • MBBS MD(Preventive and social Medicine)
Pune
Apollo Clinic, Nigdi, Pune
Dr. Madhuri Sai Sreepada
General Practitioner
9 Years • MBBS
Hyderabad
BRIGHT SMILES MEDICARE & DENTAL CARE, Hyderabad
Dr. Karanam Kondalamma
General Practitioner
4 Years • MBBS
Hyderabad
KK Clinic, Hyderabad
Frequently Asked Questions
1. Can you get measles more than once?
No, it is extremely rare. After recovering from measles, your body develops lifelong immunity against the virus. The same is true for the MMR vaccine, which provides long-lasting protection without the risk of the disease's severe complications.
2. How soon do symptoms of measles appear after exposure?
The incubation period for measles is typically 10 to 14 days. This means signs and symptoms will begin to show, on average, about two weeks after you've been exposed to the virus.
3. What does the measles rash look like compared to other rashes?
The measles rash is a red, blotchy rash that starts on the face and moves downward. Unlike chickenpox, the spots are not fluid-filled blisters and are typically not itchy. The presence of high fever and the 'Three C's' (cough, coryza, conjunctivitis) before the rash helps distinguish it from common viral rashes like roseola.
4. Are there any specific tests to diagnose measles?
Yes, a doctor can confirm measles through a blood test that checks for measles-specific IgM antibodies or by using a PCR test on a sample from your throat, nose, or urine. Apollo24|7 offers convenient home collection for tests like these to aid in diagnosis while minimising exposure risk to others.
5. What is the treatment for measles?
There is no specific antiviral treatment for measles. Medical care focuses on relieving symptoms and preventing complications. This includes rest, plenty of fluids, and fever reducers (like paracetamol). Antibiotics are only used if a secondary bacterial infection, like pneumonia or an ear infection, develops. Vitamin A supplementation has been shown to reduce complications and mortality in children.