Measles: Causes, Symptoms, Prevention, Prognosis, Treatment

Article by Dr Raghuram Y.S. MD (Ay) & Dr Manasa S, B.A.M.S

What is Measles?

Measles, also known as rubeola, is a highly contagious viral disease characterized by fever, a red rash, cough, and watery eyes. It spreads through the air via respiratory droplets when an infected person talks, coughs, or sneezes.

The virus is known for its distinctive symptoms, including a widespread red rash and small, bluish-white spots inside the mouth known as Koplik’s spots. There is no specific antiviral treatment for measles; instead, supportive care is provided to alleviate symptoms and prevent complications.

Vaccination is the most effective way to prevent measles. The measles vaccine, usually given as part of the MMR (measles, mumps, and rubella) vaccine, has significantly reduced the incidence of the disease. However, due to declining vaccination rates in some areas, outbreaks have re-emerged, underscoring the importance of maintaining high immunization levels. Unvaccinated individuals, especially those traveling to regions with low vaccination rates, are at higher risk of contracting measles.

Measles can lead to serious health complications, particularly in young children, pregnant women, and immunocompromised individuals, making vaccination crucial for public health.

Epidemiology of Measles

The epidemiology of measles varies globally and is closely tied to the levels of immunization in different regions. Here are the key points:

Global Impact:

–        Before widespread vaccination, measles caused an estimated 2.6 million deaths annually.
–        Despite modern vaccination efforts, the World Health Organization (WHO) reported about 134,200 deaths due to measles in 2015, equating to 15 deaths per hour.

Recent Data:

–        In the United States, the Centres for Disease Control and Prevention (CDC) reported 372 cases in 2018 and 764 cases by May 2019.
–        Measles is a reportable disease in most countries, including the U.S.

Transmission and Contagion:

–        Measles has no animal reservoir and only affects humans.
–        It is highly contagious, with each infected individual potentially causing 14 to 18 secondary cases among susceptible people.
–        Transmission occurs through respiratory droplets, aerosols, and close contact.

Incubation Period:

–        Typically lasts 10 to 14 days, although longer periods have been observed.

High-Risk Groups:

–        Unvaccinated young children and pregnant women are particularly at risk.
–        The disease most commonly affects young children but is now also seen in older children and adolescents due to increased immunization coverage and changing population immunity.

Infants and Immunity:

–        Young infants born to immune mothers are initially protected by passive antibody transfer, but this protection wanes, making them susceptible.

Infectious Period:

–        A person with measles is most infectious from four days before to four days after the rash appears, coinciding with peak levels of viremia and symptoms such as cough, conjunctivitis, and coryza.

Understanding the epidemiology of measles underscores the critical importance of maintaining high vaccination coverage to prevent outbreaks and reduce mortality.

Causes of Measles

Measles is caused by the morbillivirus, an extremely contagious virus. This airborne disease spreads through respiratory droplets when an infected person breathes, coughs, sneezes, or talks.

Below mentioned are the key factors that contribute to the transmission of measles:

Airborne Transmission: The primary mode of transmission is through the air. The virus can linger in the air for up to two hours after an infected person has left the room. Inhalation of these viral particles can lead to infection.

Direct Contact: Measles can spread through direct contact with an infected person. Sharing food or drinks, kissing, shaking hands, holding hands, or hugging someone with measles increases the risk of transmission.

Surface Contamination: The virus can survive on surfaces for several hours. Touching contaminated surfaces and subsequently touching the mouth, nose, or eyes can result in infection.

Maternal Transmission: Pregnant individuals can pass the virus to their babies during pregnancy, delivery, or while nursing.

Contagion Period

Individuals with measles are contagious from approximately four days before the rash appears until about four days after the rash begins. This makes the contagious period around eight days in total.

Pathophysiology of Measles

Measles is caused by a virus that spreads through droplets from coughs and sneezes. Here’s how it affects the body:

Initial Infection: The virus is inhaled and initially infects the cells in the respiratory tract, such as lymphocytes (a type of white blood cell), dendritic cells, and alveolar macrophages.

Spread: The virus then spreads to nearby lymphoid tissue and enters the bloodstream, leading to viremia (presence of the virus in the blood). This allows the virus to travel to different parts of the body.

Respiratory Transmission: Infected respiratory cells release the virus in droplets, which can infect others through coughing and sneezing. This is how measles spreads rapidly among people.

Symptoms Development

Early Symptoms: The initial inflammation causes symptoms like a runny nose (coryza), red eyes (conjunctivitis), and cough.

Fever and Rash: Fever appears when the virus is in the bloodstream, and the characteristic skin rash develops due to the body’s immune response (inflammation around blood vessels and infiltration by lymphocytes).

Immune System Responses:

–        The virus suppresses the body’s initial immune response by interfering with interferon production.
–        As the virus replicates, the body produces IgM antibodies (detectable 3-4 days after rash) and later IgG antibodies, which are crucial for lifelong immunity.
–        Cellular immune responses, involving different types of immune cells, are essential for recovery.

Immune Suppression and Recovery:

–        Measles can weaken the immune system for weeks to months, increasing susceptibility to other infections.
–        This is possibly due to “immune amnesia,” where measles-specific lymphocytes replace previous memory cells, making the body more vulnerable to new infections.

Long-term Immunity: Lifelong immunity against measles is primarily due to neutralizing IgG antibodies that prevent the virus from binding to host cells.

Understanding this pathophysiology helps in comprehending why measles is so contagious and why it can lead to severe complications, emphasizing the importance of vaccination and maintaining herd immunity.

Symptoms of Measles

Common Symptoms of Measles

Measles is a viral infection that presents with several distinctive symptoms. Recognizing these signs is crucial for early diagnosis and treatment. Here are the common symptoms of measles:

Fever: One of the first symptoms to appear, often starting mild but can escalate to high levels as the disease progresses.

Dry Cough: Persistent and often bothersome, the dry cough accompanies the early stages of measles.

Runny Nose: Similar to a common cold, a runny nose is a frequent initial symptom.

Sore Throat: Accompanied by the runny nose and cough, a sore throat is another early symptom.

Inflamed Eyes (Conjunctivitis): The eyes may become red, swollen, and watery, often making them sensitive to light.

Koplik’s Spots: Tiny white spots with bluish-white centres on a red background, found inside the mouth on the inner lining of the cheek. These spots are a hallmark of measles and appear a few days before the rash.

Skin Rash:

–        Characterized by large, flat blotches that often merge into one another.
–        The rash typically starts on the face and spreads down to the rest of the body, including the arms, chest, back, thighs, lower legs, and feet.

The signs and symptoms typically appear 10 to 14 days after exposure to the virus, occurring in distinct stages over a period of 2 to 3 weeks.

Incubation Period (10-14 days):

–        During this initial stage, the virus spreads throughout the body.

–        No symptoms are present during this period, making it asymptomatic and undetectable.

Nonspecific Signs and Symptoms:

–        Duration: Lasts 2 to 3 days.

–        Symptoms: Measles begins with mild to moderate fever accompanied by a persistent dry cough, runny nose, inflamed eyes (conjunctivitis), and a sore throat.

–        These symptoms resemble a common cold or respiratory infection.

Acute Illness and Rash:

Onset: The rash typically appears after the initial symptoms.

Characteristics:

–        The rash consists of small red spots, some slightly raised, which cluster tightly to give the skin a blotchy red appearance.

–        It starts on the face and spreads downward to the arms, chest, back, thighs, lower legs, and feet over the next few days.

Additional Signs:

–        Fever intensifies, often rising sharply to between 104 and 105.8°F (40-41°C).

–        Koplik’s spots, tiny white spots with bluish-white centers on a red background, appear inside the mouth on the inner lining of the cheeks.

–        This stage represents the peak of the illness, with the most severe symptoms.

Recovery:

–        Rash Duration: Approximately 7 days.

–        Rash Resolution: The rash gradually fades, starting from the face and moving downwards, with the thighs and feet being the last areas to clear.

–        Lingering Symptom: Cough and possible darkening or peeling of the skin where the rash was present may persist for about 10 days after other symptoms subside.

Infectious Period

–        A person with measles can transmit the virus to others from about four days before the rash appears to four days after it emerges.

–        This makes the contagious period approximately eight days in total, contributing to the rapid spread of the virus within communities.

Understanding these symptoms and the progression of measles is crucial for timely diagnosis and preventing further transmission, underscoring the importance of vaccination and public health measures.

Risk Factors for Measles

Understanding the risk factors for measles is crucial for prevention and management. The primary risk factors include:

Being Unvaccinated: Individuals who have not received the measles vaccine are significantly more susceptible to contracting the disease. The measles-mumps-rubella (MMR) vaccine is highly effective, and its absence markedly increases the likelihood of infection.

International Travel: Traveling to regions where measles is endemic or more prevalent elevates the risk of exposure and infection. International travellers are advised to ensure their vaccinations are up-to-date to mitigate this risk.

Vitamin A Deficiency: Adequate levels of vitamin A are vital for immune function. A deficiency in this nutrient can lead to more severe symptoms and complications if measles is contracted. Ensuring sufficient Vitamin A intake through diet or supplements can help reduce the severity of the disease.

Complications of Measles

Measles, while primarily a childhood illness, can lead to several serious complications, particularly in certain high-risk groups such as those with vitamin A deficiency or individuals traveling internationally where measles is more prevalent. Here are the main complications associated with measles:

Diarrhoea and Vomiting: These symptoms can lead to severe dehydration, posing a significant health risk, especially in young children.

Ear Infections: Bacterial ear infections are one of the most common complications, often resulting in pain and potential hearing loss.

Respiratory Infections: Bronchitis, Laryngitis, or Croup: Measles can cause inflammation of the airways, leading to conditions like bronchitis (inflammation of the lung’s main air passages), laryngitis (inflammation of the voice box), and croup (a severe swelling of the upper airways).

Pneumonia: A serious complication, especially in individuals with weakened immune systems, pneumonia can sometimes be fatal. It involves an infection that inflames the air sacs in one or both lungs, which can fill with fluid.

Encephalitis: Occurring in about 1 in 1,000 measles cases, encephalitis is an inflammation of the brain that can lead to permanent brain damage or death. This complication can manifest immediately following the infection or months later, posing a severe risk particularly to those with compromised immune systems.

Pregnancy Complications: Pregnant women who contract measles are at risk of premature birth, low birth weight, and foetal death. Special precautions are necessary to avoid infection during pregnancy to prevent these severe outcomes.

Prevention of Measles

The Centres for Disease Control and Prevention (CDC) provides several key recommendations for preventing measles:

Vaccination:

Children:

–        MMR Vaccine: Administered in two doses, first between 12-15 months and second between 4-6 years.
–        MMRV Vaccine: This combined vaccine includes measles, mumps, rubella, and varicella (chickenpox). It can be given in place of the MMR vaccine and is similarly effective.
–        Effectiveness: Both MMR and MMRV vaccines are 97% effective in preventing measles.

Adults: Recommended for those without immunity, especially if they are at increased risk, such as international travelers, college students, and healthcare workers.

International Travel: Children aged 6-11 months traveling internationally should receive the measles vaccine earlier than usual.

Herd Immunity: Maintaining high vaccination rates is crucial for widespread immunity and preventing outbreaks.

During Outbreaks:

–        Isolation: Infected individuals should stay home for about eight days (four days before and after rash onset).
–        Vaccination: Ensure unvaccinated individuals receive the vaccine promptly.

Following these guidelines helps reduce the spread of measles and protects those who are most vulnerable to severe complications.

Measles Diagnosis

Measles is typically diagnosed through its distinctive symptoms, including a characteristic rash and Koplik’s spots—small bluish-white spots on a red background inside the cheek.

 Healthcare providers may inquire about vaccination history, recent international travel, and contact with anyone showing symptoms of rash or fever.

 In uncertain cases, a blood test, throat swab, or urine sample can confirm the diagnosis.

Treatment

There is no specific antiviral treatment for measles once infection occurs. Management focuses on relieving symptoms and preventing complications:

Post-exposure Measures:

–        Vaccination: Administering the measles vaccine within 72 hours of exposure can prevent or mitigate the disease.
–        Immune Serum Globulin: Given within six days of exposure to pregnant women, infants, and immunocompromised individuals, these antibodies can prevent or lessen measles severity.

Medications:

–        Fever Reducers: Acetaminophen, ibuprofen, or naproxen sodium can help manage fever. Avoid aspirin in children due to the risk of Reye’s syndrome.
–        Antibiotics: Prescribed if bacterial infections like pneumonia or ear infections develop.
–        Vitamin A: Supplementation for children with low levels of vitamin A can reduce measles severity, typically given in large doses.

Self-Care

–        Rest: Ensure adequate rest and avoid strenuous activities.
–        Hydration: Drink plenty of fluids such as water, fruit juice, and herbal tea.
–        Humidification: Use a cool-mist humidifier to ease cough and sore throat.
–        Nasal Care: Saline nasal sprays can keep nasal passages moist.
–        Eye Comfort: Reduce exposure to bright light, and rest eyes by avoiding reading or screen time.

Related studies and research

Study – ‘Measles virus infection diminishes preexisting antibodies that offer protection from other pathogens’ states a study.

Study – ‘Birth by C-section more than doubles odds of measles vaccine failure’ states yet another study. Researchers therefore say that it is vital that the children born by caesarean section shall receive two doses of measles vaccine for robust protection against the disease.

Study – ‘Measles continues to cause death and severe disease in children worldwide. Complications from measles can occur in almost every organ system. Measles remains a common cause of blindness in developing countries’.

Study – ‘Following measles, children had increased rates of diagnosed infections, requiring increased prescribing of antimicrobial therapies. This study supports the hypothesis that measles has a prolonged impact on host resistance to non-measles infections diseases’.

Measles: Ayurveda Understanding

A disease named ‘Romantika’ has been correlated with measles. We find a two-line verse describing this condition similar to measles in the context of the Masurika Nidanam chapter of Madhava Nidana. We do not get a detailed elaboration of this condition. Master Charaka has described this condition in short, in a two-line verse in ‘Shvayathu Chikitsa Adhyaya’ which deals with treatment of different kinds of swellings. Master Sushruta has not explained this condition.

The disease presents with small red eruptions occurring at the roots of hairs making slight elevations / bumps, giving them an appearance of raised sweat glands or pores. It is caused by aggravation of kapha and pitta and is associated with cough, loss of taste and is preceded by presence of fever. (Madhava Nidana 54/13)

According to Master Charaka, it is caused by aggravated pitta and kapha and is characterized by small eruptions all over the body, is associated with fever, severe thirst, burning sensation, excessive salivation and anorexia. (Charaka Chikitsa 12/92)

According to Master Charaka, this condition needs to be treated on the lines of treating Visarpa or Kushta.

Related Reading – ‘Romantika – causes, symptoms, types, prognosis, treatment’