Hong Kong Airport Measles Cases Prompt Public Health Alert

Hong Kong health authorities are investigating a cluster of measles cases linked to the city’s international airport, raising concerns about potential community spread. As of late April 2025, three confirmed cases have been identified among airport staff, marking a notable resurgence of the highly contagious virus in a setting frequented by international travelers.

The cases involve workers at Hong Kong International Airport (HKIA), including a 37-year-old employee who tested positive in mid-April. Subsequent investigations revealed two additional infections among colleagues, prompting the Centre for Health Protection (CHP) to launch contact tracing and vaccination outreach efforts.

Understanding the Measles Threat

Measles is a viral infection caused by the measles virus, a member of the Paramyxoviridae family. It spreads through respiratory droplets when an infected person coughs or sneezes and can remain airborne or on surfaces for up to two hours. The virus is exceptionally contagious — one infected individual can transmit measles to up to 90% of unvaccinated close contacts.

Symptoms typically appear 10 to 14 days after exposure and include high fever, cough, runny nose, red eyes, and a characteristic red rash that begins on the face and spreads downward. Complications can be severe, particularly in young children, pregnant women, and immunocompromised individuals, and may include pneumonia, encephalitis, and, in rare cases, death.

Vaccination remains the most effective preventive measure. The measles, mumps, and rubella (MMR) vaccine is about 97% effective after two doses and has led to the elimination of endemic measles in many regions. However, gaps in vaccination coverage — due to hesitancy, access issues, or missed doses — can allow the virus to reestablish transmission chains.

Response from Hong Kong Health Authorities

The Centre for Health Protection confirmed the first case on April 15, 2025, involving an airport worker who developed symptoms after returning from overseas duty. Laboratory testing confirmed measles infection, prompting an immediate investigation into potential exposures at the airport and during travel.

By April 22, two additional cases were identified among close coworkers, all of whom had not received two documented doses of the MMR vaccine. The CHP has since:

• Notified all potentially exposed airport staff and passengers.
• Offered free MMR vaccinations at airport clinics and nearby public health centers.
• Issued alerts to airlines and ground handling companies to monitor employee health.
• Reinforced infection control protocols in airport terminals and staff facilities.

Dr. Edwin Tsui, Controller of the Centre for Health Protection, emphasized the importance of vaccination: “Measles is preventable. We urge all airport workers and residents to check their vaccination status and receive the MMR vaccine if they are not fully protected.”

Broader Context: Measles Resurgence Globally

Hong Kong’s cases reflect a worrying global trend. According to the World Health Organization (WHO), measles cases increased by 79% worldwide in 2023 compared to the previous year, with over 9 million infections and 136,000 deaths reported — mostly among children.

Factors contributing to the resurgence include disruptions to routine immunization during the COVID-19 pandemic, vaccine misinformation, and uneven access to healthcare in certain regions. Even areas with previously high immunity, like Hong Kong, are vulnerable when vaccination rates dip below the 95% threshold needed for herd immunity.

In Hong Kong, childhood MMR coverage remains high at over 95%, but adult vaccination rates — particularly among foreign domestic workers and transient airport staff — can be lower. Authorities are now reviewing occupational health policies to ensure all airport employees have verifiable immunization records.

What Travelers and Workers Should Know

For individuals passing through or working at Hong Kong International Airport:

• Check your vaccination records: Ensure you have received two doses of the MMR vaccine, especially if born after 1967 or if you function in healthcare, education, or aviation.
• Watch for symptoms: Fever, cough, and rash following recent travel or airport exposure warrant prompt medical evaluation.
• Isolate if symptomatic: Suspected cases should avoid public spaces and contact healthcare providers in advance to prevent further spread.
• Practice hygiene: Regular handwashing and mask use in crowded indoor settings can reduce transmission risk.

There is no specific antiviral treatment for measles. Care is supportive, focusing on fever reduction, hydration, and monitoring for complications. Vitamin A supplementation is recommended for children with measles to reduce mortality risk, per WHO guidelines.

Key Takeaways

• Three measles cases have been confirmed among Hong Kong International Airport staff as of April 2025.
• All infected individuals were unvaccinated or under-vaccinated against measles.
• The Centre for Health Protection is conducting contact tracing and offering free MMR vaccinations.
• Measles is highly contagious but preventable with two doses of the MMR vaccine.
• Travelers and workers should verify their immunization status and seek care if symptoms develop.

Frequently Asked Questions

Can I get measles if I’ve been vaccinated?

Extremely rarely. The MMR vaccine is 97% effective after two doses. In rare cases, vaccinated individuals may experience a mild form of the disease, but they are much less likely to transmit it to others.

Is it safe to travel through Hong Kong airport right now?

Yes. The risk to the general public remains low due to high community immunity and rapid public health response. Authorities continue to monitor the situation closely.

How long is someone with measles contagious?

Individuals with measles are contagious from four days before the rash appears to four days after — meaning they can spread the virus before knowing they are sick.

Where can I get the MMR vaccine in Hong Kong?

The MMR vaccine is available free of charge at public clinics, private doctors’ offices, and through occupational health programs. The CHP has set up temporary vaccination stations at the airport for staff.

What should I do if I think I was exposed?

Monitor for symptoms for 21 days after exposure. If fever or rash develops, contact a healthcare provider immediately and inform them of your potential exposure so they can take precautions.

This article is based on information from the Centre for Health Protection (Hong Kong), the World Health Organization, and peer-reviewed public health guidelines. All facts were verified as of April 2025. For updates, visit the Centre for Health Protection website or consult your healthcare provider.