Introduction

A brief overview of measles

Measles is a highly contagious viral disease with a prodromal phase, which is the onset of the disease, characterised by fever, coryza, cough, and conjunctivitis, followed by a generalised maculopapular rash. The causative agent is the measles virus, which belongs to the Morbillivirus genus within the Paramyxoviridae family.¹

Importance of understanding diagnosis and treatment

Public health implications

Understanding the diagnosis and treatment of measles is important for public health because of its high contagion potential and its significant impact on morbidity and mortality. Measles can lead to severe complications such as pneumonia, encephalitis, and even death, particularly in children. Despite the availability of an effective vaccine, measles remains a leading cause of vaccine-preventable deaths worldwide.^1,2

Prevention of outbreaks

Preventing measles outbreaks requires maintaining high levels of population immunity. This can be achieved through widespread vaccination, which protects individuals and provides herd immunity, helping to reduce the overall incidence of the disease. Continuous monitoring and rapid response to outbreaks are essential in controlling the spread. Public health initiatives must focus on increasing vaccination coverage and ensuring vaccine availability, especially in underserved areas.^1,2

Measles diagnosis

Clinical diagnosis

Initial symptoms

Measles typically begins with a high fever, cough, coryza, and conjunctivitis. These initial symptoms, often known as the “three Cs” (cough, coryza, and conjunctivitis), precede the appearance of the characteristic rash.^1,2 

Rash development

The measles rash usually appears 3-4 days after the onset of the initial symptoms. It typically starts on the face, particularly behind the ears, and then spreads to the trunk and extremities. This maculopapular rash progresses from erythematous macules to papules and may persist for 3-4 days. In some cases, especially among malnourished people, the rash can become deeply pigmented and desquamate during recovery.^1,2 

Koplik spots

Koplik spots are a specific sign of measles. These are small, white lesions on the buccal mucosa, typically appearing a day or two before the rash. They provide an early clinical diagnostic clue before the rash develops, allowing for prompt identification of the disease.²

Physical examination findings

A physical examination of a patient suspected of having measles will reveal the characteristic rash, Koplik spots, and signs of complications may also be present, such as pneumonia, otitis media, or keratoconjunctivitis. In severe cases, signs of malnutrition and immune suppression may be observed, especially in patients with underlying conditions such as HIV.

Laboratory diagnosis

Serology

Measles-specific IgM antibodies

Detecting measles-specific IgM antibodies in serum or plasma is the primary method for confirming an acute measles infection. These antibodies typically become detectable 4 days after rash onset, peaking within 1-3 weeks. However, early sampling may result in false-negative results if IgM levels have not yet risen sufficiently.^1,2

IgG antibody seroconversion

Diagnosis can also be confirmed by demonstrating a four-fold or greater increase in measles-specific IgG antibodies between acute and convalescent serum samples. This seroconversion indicates a recent infection and helps confirm the diagnosis when IgM results are inconclusive.¹

Differential diagnosis

Rubella

Rubella has a similar rash but normally involves milder symptoms. The rash of rubella is less intensely red and spreads more rapidly. Other symptoms may include mild fever, headache, and lymphadenopathy, which can help differentiate rubella from measles.³

Roseola

Roseola, caused by human herpesvirus 6, commonly affects infants and young children. It features a sudden high fever that resolves abruptly, followed by a pinkish rash. The sequence of fever followed by a pinkish rash is a key distinguishing factor.³

Scarlet fever

Scarlet fever, caused by group A Streptococcus, presents with a fine, red, sandpaper-like rash. It is usually accompanied by a sore throat and high fever, which can help differentiate it from measles.³

The correct diagnosis of measles through both clinical and laboratory methods is important for effective management and outbreak control. Understanding the differential diagnoses helps to prevent misdiagnosis and ensure appropriate public health interventions.³

Measles treatment

Symptomatic treatment

Fever management

Fever, a common symptom of measles, can be managed with medications such as paracetamol or ibuprofen. These medications help reduce fever and alleviate associated aches and pains. It is important to avoid aspirin in children under 16 years old due to the risk of Reye’s syndrome.^1,2

Hydration and nutritional support

Maintaining adequate nutrition is crucial, especially in cases where fever and diarrhoea may lead to dehydration. Drinking fluids and ensuring proper nutrition can help support the immune system during recovery.²

Management of complications

Measles can lead to serious complications such as pneumonia, encephalitis, and severe diarrhoea. These complications require specific treatments:^1,2

• Pneumonia may require antibiotics if it is bacterial
• Encephalitis often requires hospitalisation and intensive supportive care
• Severe diarrhoea should be managed with rehydration solutions to prevent dehydration

Vitamin a supplementation

Dosage and administration

The World Health Organisation (WHO) recommends high-dose vitamin A supplementation for children with measles, particularly in areas where vitamin A deficiency is prevalent. The typical dosage is 200,000 IU for children over one year old, administered once daily for two consecutive days.⁴

Impact on measles outcomes

Vitamin A supplementation has been shown to reduce the severity and duration of measles symptoms, as well as the risk of complications and mortality. This is because vitamin A plays a critical role in maintaining the integrity of epithelial tissues and supporting the immune system.⁴

Isolation and infection control

Preventing spread in healthcare settings

In healthcare settings, patients with measles should be placed in airborne infection isolation rooms (AIIR) to prevent the spread of the virus. Healthcare personnel should use respiratory protection, such as N95 respirators, and follow strict infection control protocols.

Recommendations for home isolation

To prevent the spread of measles to others, individuals with measles should stay home from school or work for at least four days after the rash appears. Good hygiene practices, such as regular hand washing and using tissues when sneezing, are also recommended.

Hospitalisation criteria

Severe cases

Hospitalisation is necessary for severe cases of measles, particularly when complications such as pneumonia, encephalitis, or severe dehydration occur. Intensive supportive care and close monitoring are required in these instances.

High-risk groups

High-risk groups, including infants, pregnant women, and immunocompromised individuals, are more susceptible to severe complications from measles. These individuals often require hospitalisation and specialised care to manage the disease effectively.⁵

By following these treatment protocols and preventive measures, the burden of measles can be significantly reduced, protecting vulnerable populations and preventing further outbreaks.^2,4,5

Measles prevention

Vaccination

MMR vaccine

Vaccination schedule

The measles, mumps, and rubella (MMR) vaccine is typically administered in two doses. The first dose is recommended at 12-15 months of age, and the second dose is given at 4-6 years of age. In some circumstances, such as during outbreaks or for individuals in high-risk settings, the schedule may be adjusted to provide earlier or additional doses to enhance immunity.²

Effectiveness and coverage

The MMR vaccine is highly effective, with the first dose providing about 93% immunity against measles and the second dose increasing this to approximately 97%. Global efforts have significantly increased vaccination coverage; however, achieving and maintaining high coverage rates is essential for interrupting measles transmission. Despite these efforts, some regions still experience suboptimal coverage, highlighting the need for ongoing vaccination campaigns and public health initiatives.²

Herd immunity

Herd immunity occurs when a high percentage of the population is immunised against a contagious disease, thereby providing indirect protection to unvaccinated individuals. For measles, a highly contagious virus, about 95% of the population needs to be vaccinated to achieve herd immunity. This high level of vaccination helps prevent outbreaks and protects those who cannot be vaccinated, such as infants and individuals with certain medical conditions.

Public health measures 

Surveillance and outbreak control

Effective surveillance systems are critical for monitoring measles incidence and promptly identifying outbreaks. Public health authorities must conduct thorough case investigations, implement quarantine measures, and initiate outbreak response immunisation campaigns to contain and control the spread of measles.⁵

Education and awareness campaigns

Education and awareness campaigns are crucial for promoting vaccination and dispelling myths. They emphasise the benefits of vaccination, the risks of measles, and the need for widespread coverage. Collaborating with healthcare providers, community leaders, and the media amplifies their impact.⁵

Summary

• The highly contagious measles virus causes measles, which is characterised by a prodromal phase (the onset of the infection) followed by a distinctive rash
• Accurate diagnosis and timely treatment are essential for managing complications and preventing outbreaks
• Vaccination, particularly with the MMR vaccine, plays a vital role in preventing measles and achieving herd immunity
• Public health initiatives should focus on increasing vaccination rates and improving global vaccine access