Measles: Frequently Asked Questions for Health Providers
1. What is measles?
Measles is a highly contagious viral infection caused by the Measles morbillivirus. It primarily affects the respiratory system and can lead to severe complications such as pneumonia, encephalitis, and death, especially in young children and immunocompromised individuals.
2. How is measles transmitted?
Measles spreads through respiratory droplets when an infected person coughs or sneezes. The virus can remain airborne or live on surfaces for up to two hours. Measles has a high reproduction rate (R₀ of 12–18), making it one of the most contagious diseases.
3. What are the symptoms of measles?
Symptoms appear 7–14 days after exposure and progress through stages:
• Prodromal Phase (2–4 days): High fever, cough, coryza (runny nose), conjunctivitis (the "3 Cs").
• Koplik’s Spots (1–2 days before rash): Tiny white spots with a red halo on the buccal mucosa.
• Rash (3–5 days after symptom onset): Begins on the face and spreads downward. It is maculopapular and often confluent.
4. How is measles diagnosed?
• Clinical Diagnosis: Based on characteristic symptoms.
• Laboratory Confirmation:
o RT-PCR or viral culture (nasopharyngeal/throat swab, urine).
o Measles IgM and IgG serology (IgM detectable ~3 days after rash onset).
5. What is the treatment for measles?
• Supportive Care: Hydration, fever control (acetaminophen), and vitamin A supplementation (recommended for children to reduce complications).
• Hospitalization: For severe cases or complications (pneumonia, encephalitis).
• Isolation: Infected individuals should be isolated for at least four days after rash onset.
6. How can measles be prevented?
• Vaccination (MMR or MMRV):
o First dose at 12–15 months.
o Second dose at 4–6 years.
o Two doses provide ~97% protection.
• Post-Exposure Prophylaxis (PEP):
o Within 72 hours: MMR vaccine for unvaccinated individuals.
o Within 6 days: Immune globulin (IG) for high-risk individuals (infants <12 months, pregnant women, immunocompromised).
7. What should healthcare providers do during an outbreak?
• Identify and report cases immediately to public health authorities.
• Implement airborne precautions for suspected cases.
• Conduct contact tracing and offer PEP.
• Ensure healthcare workers are immune (documented vaccination or serologic evidence).
8. Who is at the highest risk for complications?
• Infants and young children
• Pregnant women
• Immunocompromised individuals
• Malnourished individuals, especially those with vitamin A deficiency
9. How long does immunity last after measles infection or vaccination?
• Natural infection provides lifelong immunity.
• Two doses of MMR vaccine generally provide long-term immunity, but rare cases of waning immunity have been reported.
10. Are there special considerations for healthcare workers?
Yes. All healthcare workers should have documented immunity (two doses of MMR or positive measles IgG titer). If exposed and unvaccinated, they should be excluded from work from day 5–21 after exposure.