The Dark Side of Measles

The government must promptly respond to the International Health Regulation notification. This is because, after visiting Indonesia, two Australian citizens were exposed to measles. The highly contagious disease even claimed the life of an intern doctor at RSUD Cimacan-Cianjur. He was still very young, 26 years old. His death has simultaneously triggered a danger alarm. This is the first mortality case in a young adult individual. It means that measles should never be underestimated. The general public perception is that measles is not dangerous and only affects children.

Indonesia has received ‘red’ status for the extraordinary measles incident (KLB). Its ranking is second among all countries in the world, after Yemen. According to the Ministry of Health, the pattern has fluctuated since the beginning of 2026. The KLB is spread across 39 districts/cities in 14 provinces.

The measles virus has the highest transmissibility hierarchy among all infectious diseases, including COVID-19. If someone is infected, it is predicted that 90% of people around them will also be exposed. Especially if they lack immunity to measles. Transmission occurs from four days before until four days after the appearance of the rash. The pattern is exactly the same as COVID-19, through droplets when coughing, sneezing, or speaking. It can also occur through surfaces contaminated by droplets, then touching the eyes, nose, or mouth of nearby individuals.

IMMUNITY

A robust immune system is the spearhead in fighting infections. At all times, various microbes have the opportunity to invade. Immune system dysfunction triggers infection risks at various levels. Although it can heal on its own, measles poses dangers to toddlers and the elderly. This is because their immune system spectrum is not at peak level. In toddlers, it has not developed optimally, while in the elderly, its performance begins to diminish.

The risk of danger in young adults is relatively low. However, if they experience immunocompromise, the probability of complications increases. The causes are varied. For example, chronic diseases (tuberculosis, HIV/AIDS, diabetes, autoimmune diseases, cancer). Obesity and unhealthy lifestyles, such as lack of sleep, excessive fatigue, stress, smoking, alcohol consumption, and nutritional deficiencies, also trigger immunocompromise.

KLB

There are only two analyses why measles is spreading. First, the global transmission rate is increasing. Based on a release from the World Health Organization (WHO), outbreaks have occurred in the United States and Mexico. Recorded in 2011, 2014, 2018, 2019, and most recently in July 2025. The incidence is the highest in the last three decades. Yet in 2000, measles was declared eradicated in the US.

Canada lost its measles elimination status on 10 November 2025. Although it had declared elimination in 1998. Europe faces a similar fate. Nearly 60,000 cases were detected in 45 out of 53 countries in the ‘Blue Continent’ region. According to UNICEF, the outbreak has spread to more than a hundred countries and has infected 10.3 million people worldwide in 2023. It is categorised as eliminated if transmission stops in a geographical area for at least 12 months.

Second, increasing global vulnerability due to declining vaccination coverage, especially since 2023. Epidemiological facts prove that the more individuals who are unvaccinated, the higher the risk of outbreaks. There is a research model that can predict the correlation. If MMR vaccination coverage reaches 97%, the chance of an outbreak is only 16%. If coverage is 70%, the outbreak probability is predicted to increase to 78%. As many as 95% of reported measles cases in the US have never been vaccinated. Especially in individuals who experience complications up to death.

Why does the measles KLB always recur? Even though vaccination has proven to be the most effective and efficient modality in eradicating infectious diseases. The most dramatic example is the eradication of smallpox. Vaccines succeeded in ending the smallpox pandemic, although it took about 200 years.

WHO declared eradication on 8 May 1980. Vaccines also mitigated the COVID-19 pandemic. Their effectiveness is not 100%, but they have succeeded in ending the pandemic. Misinformation and the emergence of anti-vaccine groups colour the challenges in their implementation. The pattern differs in each country. Now, similar challenges are faced in eradicating the measles outbreak. Not only in Indonesia, but also in other countries.

Over the last two decades, Robert F. Kennedy Jr (RFK) has actively promoted the theory of autism triggers. He has vigorously accused thimerosal as the cause through the Children Health Defense organisation he founded. Thimerosal, which is mercury-based, is commonly used as a vaccine preservative. Now, through evidence-based medical research, it has been proven that there is no connection between autism and thimerosal.

However, reality says otherwise. Parents in the US have become reluctant to vaccinate their children due to concerns. To avoid widespread impact on vaccination programmes, thimerosal has been gradually replaced with other preservatives. RFK’s activities have greatly influenced public thinking in the US and the world regarding rejection of vaccination programmes.

Vaccine misinformation in Indonesia is instead linked to halal issues, fear of side effects, and feeling it is not needed. However, authorities have guaranteed that such opinions are untrue.

PREVENTIVE-VACCINATION

Clean and healthy living behaviours (PHBS) are a preventive modality that should be practised. The use of masks is highly recommended, especially if in crowds or at-risk environments. MMR vaccination (Measles, Mumps, and Rubella) is the best preventive modality. In addition to being safe, its effectiveness reaches 97% after two doses. In children, MMR can be combined with the varicella vaccine. It is called MMRV. After vaccination, the majority will be protected for life. Medical personnel and international tourists who lack immunity should be prioritised for vaccination.

Hopefully, outbreak response immunisation can prevent the measles outbreak.