Measles is one of the most contagious infections known. A single case in an unprotected room leaves virus suspended long enough to infect anyone who enters up to two hours later. Nine out of ten susceptible people exposed to a case will catch it. These numbers have not changed. What has changed, in 2026, is where the susceptible people are — and why they got that way.
This piece is not primarily about the disease. It is about how three very different settings ended up in the same place, and what that means for Malaysia specifically.
Bangladesh and the United States are both in the middle of large measles outbreaks right now. In Bangladesh, the WHO was notified of a significant increase in cases on 4 April 2026, with transmission reported across all eight divisions and 58 of 64 districts. By early April, 9,883 suspected cases and 1,398 laboratory-confirmed cases had been reported, with at least 128 suspected and 21 confirmed deaths. Cases declined in June and July following the emergency vaccination campaign, then resurfaced sharply in August — with daily suspected case counts regularly exceeding 1,200 and daily hospitalisations topping 1,000. As of 16 September 2026, 172,720 suspected cases, 19,933 laboratory-confirmed infections, and 1,030 deaths classified by DGHS as confirmed or suspected measles deaths — comprising 100 confirmed and 930 suspected measles deaths — had been recorded since 15 March, with more than 152,000 patients hospitalised. The outbreak remains active; authorities are preparing a further round of vaccinations focused on reaching children missed by previous campaigns. In the United States, 3,134 confirmed cases had been reported across 47 jurisdictions as of 3 September 2026 — the highest annual total in more than 35 years — with two measles-associated deaths in Pennsylvania under CDC review.
Neither outbreak is an isolated event. In January 2026, WHO confirmed that six countries — Armenia, Austria, Azerbaijan, Spain, the United Kingdom, and Uzbekistan — had lost their measles elimination status, joining Canada, which lost it the previous year. Mexico, India, Yemen, Pakistan, and most of continental Europe are all in active outbreak. In England alone, 933 cases were reported in the first part of 2026. Across the Americas, PAHO documented a 32-fold surge in cases in 2025 compared to the prior period. Globally, first-dose measles vaccine coverage stood at 84% in 2025. In 2024, an estimated 95,000 people died from measles — mostly children under five — despite the availability of a safe and effective vaccine that has averted 59 million deaths since 2000. The 2026 figures, when they are complete, will be worse.
Bangladesh and the United States are the two largest and most structurally distinct outbreaks within this wider picture. The clinical disease in Dhaka and in South Carolina is the same. The reasons are not.
| ~90% | of susceptible close contacts infected by a single case |
| 4 days | infectious before the rash appears |
| 93% | protection after one MMR dose |
| 97% | protection after two doses |
In this piece
What the disease is
Measles spreads through respiratory droplets and airborne particles. It infects only humans and has no animal reservoir — which is why measles is theoretically eradicable, and why sustained transmission is ultimately preventable when sufficiently high population immunity is maintained. The incubation period runs from 10 to 14 days from exposure to the onset of symptoms. A person can transmit measles from about four days before until four days after the rash appears — making presymptomatic recognition and isolation difficult.
The illness runs in two stages. The prodrome lasts three to five days: high fever, runny nose, cough, and conjunctivitis — the “three Cs” — followed by Koplik’s spots, a highly characteristic early finding. Koplik’s spots are small, bluish-white specks on a red base on the inside of the cheek, typically opposite the lower molars. They appear one to two days before the rash and disappear within 48 hours of its onset. In the appropriate clinical and epidemiological setting, they should immediately raise measles to the top of the differential diagnosis and prompt notification and laboratory confirmation. Most clinicians who have not encountered measles in practice miss them. Photograph them immediately — they are gone within 48 hours. What to Do If You Think It’s Measles covers the immediate clinical steps.
Suspected measles should not sit in a waiting room: isolate the patient promptly, use appropriate airborne precautions, and notify public health authorities without waiting for laboratory confirmation.
The exanthem begins on day three to five: a maculopapular rash starting at the hairline and behind the ears, spreading downward over two to three days. It blanches under pressure, which distinguishes it from petechial and purpuric rashes. Recovery takes another week.
Complications are common enough that the word “uncomplicated” deserves scrutiny every time it is used. Diarrhoea occurs in roughly 8% of cases and is the leading cause of death in young children in low-income settings. Pneumonia — viral or secondary bacterial — occurs in about 5% and is the leading cause of measles mortality overall. Otitis media in about 7%, with a significant risk of permanent hearing loss. Acute disseminated encephalomyelitis occurs in about 1 in 1,000 cases, with 10 to 20% mortality and frequent permanent deficits in survivors. Subacute sclerosing panencephalitis — SSPE — is uniformly fatal, presenting years to a decade after the original infection, and occurs in roughly 1 in 10,000 cases — with much higher rates in children infected before their second birthday. Malnutrition, vitamin A deficiency, and immunocompromise each substantially worsen outcomes.
This matters particularly in Bangladesh. High levels of malnutrition among children were identified by UNICEF as a critical risk factor amplifying the severity and death rate of the current outbreak — one in four Bangladeshi children under five are stunted, and one in ten suffer from acute malnutrition — against the background of a reported case-fatality rate of approximately 1%, compared with around 0.1–0.3% in the United States. Malnutrition is likely one contributor to severity, but differences in surveillance, ascertainment, age distribution and access to care all play a role in that comparison. Measles in pregnancy is associated with premature labour, miscarriage, and low birthweight.
What treatment consists of
There is no antiviral drug specific to measles. Supportive care includes adequate hydration, antipyretics, and close monitoring for complications. Antibiotics are indicated when secondary bacterial infection is suspected or confirmed, particularly bacterial pneumonia or otitis media.
Vitamin A is actively prescribed, not merely supportive. WHO recommends two doses on consecutive days for all children under five with measles — 200,000 IU for children over 12 months, 100,000 IU for infants 6 to 11 months, 50,000 IU for infants under 6 months — with a third dose 4 to 6 weeks later if there are clinical signs of vitamin A deficiency such as Bitot’s spots. Vitamin A supplementation has been associated with reduced morbidity and mortality in children with measles, particularly in young children and populations at risk of vitamin A deficiency; the evidence is strongest in settings where deficiency is prevalent. In Bangladesh, only one of the two annual supplementation rounds was completed in 2025 — a fact worth holding when reviewing the outbreak’s death toll.
For SSPE there is no curative treatment; for severe or immunocompromised measles, ribavirin has been used off-label with limited evidence. With measles, prevention does what treatment cannot.
The vaccine in detail
The measles vaccine is a live attenuated virus, given as part of the combined MMR (measles-mumps-rubella) or MMRV formulation. One dose is approximately 93% effective; two doses are 97% effective. The second dose is primarily intended to immunise those who failed to respond to the first dose, rather than simply to boost waning immunity. Measles and rubella protection from the two-dose schedule is durable across decades of follow-up data.
Most countries give the first dose at 12 to 15 months and the second at 4 to 6 years. Malaysia’s schedule is compressed: first dose at nine months, second at 12 months, driven by continuing regional circulation. The nine-month dose in a child with residual maternal antibodies may have lower immunogenicity than one given after 12 months — this is the trade-off the schedule accepts in exchange for earlier coverage.
Three situations modify the standard schedule. In outbreak settings, WHO allows vaccination from six months; Bangladesh lowered the eligibility age to six months during the current outbreak, with doses given before 12 months not counting toward the standard series and requiring re-dosing later. For infants aged 6 to 11 months travelling to areas with active measles transmission — which in 2026 includes many countries and regions worldwide — one MMR dose is recommended before departure, with two further doses required at routine ages on return. For post-exposure prophylaxis, MMR given within 72 hours of exposure may prevent or modify infection; immunoglobulin given within six days is the alternative for those who cannot receive live vaccine — immunocompromised individuals, infants under six months, pregnant women.
Because measles is so contagious, sustained elimination generally requires at least 95% population coverage with two doses — and that coverage must be distributed evenly rather than concentrated in national averages. In the United States, only 10 states reached 95% among kindergartners in the 2025–2026 school year, against a national average that has fallen from 95.2% in 2019 to 92.4% — and Idaho’s coverage stands at 78.5%. That gap is measurable. What is happening in the United States is the epidemiological consequence of susceptible populations accumulating within communities.
Bangladesh: when a programme frays
Bangladesh entered 2026 with widening immunisation gaps, depleted vaccine stocks, and a growing population of zero-dose children. A nationwide MR vaccine stockout between 2024 and 2025 — combined with the absence of any nationwide supplementary measles-rubella campaign since 2020 — had left large cohorts of unprotected children by the time the outbreak began.
After Sheikh Hasina’s government was ousted in 2024, the interim government introduced procurement reforms shifting away from UNICEF’s system toward open bidding. Rana Flowers, UNICEF’s Representative to Bangladesh, said she warned the interim government on at least ten separate occasions. As she put it at a press conference: “I sat with the interim adviser and the staff on at least 10 occasions, saying, we are worried. Look at my face. I am worried.” The political transition and procurement disruption appear to have compounded pre-existing immunity gaps and declining routine coverage — the kind of accumulated vulnerabilities that WHO and UNICEF describe as typically underlying measles resurgences rather than any single cause. The virus found the resulting gap.
The demographic picture, documented in UNICEF’s Situation Report #1, is stark: 81% of cases in children under five, 34% in infants under nine months who were below vaccination age, 72% in unvaccinated individuals, 16% in the partially vaccinated. At the Infectious Diseases Hospital in Dhaka, over 90 patients were admitted in a single day. The Government allocated Tk 604 crore (US$49.3 million) for emergency vaccine procurement and launched a phased emergency measles-rubella vaccination campaign beginning 5 April in 30 high-risk upazilas, progressively expanding it nationwide over the following weeks. By 28 May, 18 million had been vaccinated. Cases declined in June and July — then resurfaced sharply in August, with daily suspected cases regularly exceeding 1,200 and daily hospitalisations topping 1,000. The DGHS director general attributed the resurgence to children who had not received the vaccine; an additional intensive vaccination programme and a further campaign planned for later in September are underway. As of 16 September 2026, 172,720 suspected cases, 19,933 laboratory-confirmed infections, and 1,030 deaths — comprising 100 confirmed and 930 suspected measles deaths — had been recorded since 15 March, with more than 152,000 patients hospitalised. The DGHS spokesman acknowledged that herd immunity had not been achieved, and authorities are preparing a further targeted round of vaccinations focused on micro-planning — identifying and reaching susceptible children community by community — rather than another broad national campaign. The pattern illustrates a point the numbers alone do not: vaccination campaigns, however large, take time to interrupt established transmission chains, and infants below nine months — too young for routine vaccination — remain particularly vulnerable while community transmission continues.
The United States: when a choice becomes a policy
The United States declared measles eliminated in 2000. As of 10 September 2026, 3,294 confirmed cases had been reported across 47 jurisdictions — the highest annual total since the US declared measles eliminated in 2000 — with 95% in unvaccinated individuals or those with unknown vaccination status. 38 outbreaks have been recorded in 2026, with 95% of confirmed cases outbreak-associated. Pennsylvania has recorded two measles-associated deaths: the Lancaster County coroner confirmed a measles-associated infant death, and a 40-year-old unvaccinated woman died from measles-related complications on 13 September 2026 — a rare adult fatality, and the second confirmed death of the outbreak. CDC's National Center for Health Statistics had not yet formally recorded either death in its national count at the time of publication, noting it is developing standardised classification criteria in coordination with state epidemiologists.
Dr Jennifer Nuzzo, who heads the Pandemic Center at Brown University, said in a July 2026 NPR interview that the US should by all measures already have lost its eliminated status, describing the pattern as “Whac-A-Mole” — states that contained outbreaks are seeing recurrence, pointing to re-establishing endemic transmission rather than isolated events. She attributed the resurgence to vaccine hesitancy driven by political rhetoric and noted that confusing messaging from the Department of Health and Human Services had complicated the public health response.
The mechanism here appears different from Bangladesh. Bangladesh’s coverage fell because a public health system frayed under political transition and procurement disruption. In the United States, by contrast, vaccine hesitancy and refusal have become important drivers of declining coverage in some communities, alongside other local barriers to vaccination. Several outbreaks have been concentrated in some Mennonite and Amish communities where vaccination coverage has been substantially below the level needed to prevent sustained transmission, even where overall state coverage appears adequate. D8 genotype transmission has been documented across the United States, Canada and Mexico, illustrating how measles can move rapidly across borders through susceptible populations. A 35-year high in a wealthy country with established vaccine supply, extensive cold-chain infrastructure and broadly available vaccination cannot be explained primarily by vaccine scarcity. It is, to a substantial degree, a decision aggregate.
A brief note on Malaysia
Malaysia is not in a measles crisis, but it is not a disinterested observer. MOH launched a nationwide supplementary immunisation activity in August 2025, targeting children aged 6 to 59 months for a third dose, with stated national MMR coverage exceeding 95% annually. That headline figure is reassuring. The detail behind it is less so.
In a written parliamentary reply dated 27 August 2025, as reproduced in full by Ova/Galen Centre and reported by CodeBlue, Health Minister Dzulkefly Ahmad confirmed that Malaysia recorded 3,791 measles cases in 2024 — nearly double the 2,002 cases in 2023, and a 693% increase from 2020. Sabah accounted for 2,015 of those 3,791 cases, more than half the national total. The number of outbreaks rose from 112 in 2023 to 231 in 2024. And despite national coverage exceeding 95%, only 62% of districts had actually reached that threshold. Administrative national coverage, however, is not the same thing as evenly distributed population immunity: district-level gaps, missed second doses and primary vaccine failure leave susceptible clusters behind. Malaysia's National Fatwa Council has declared the MMR vaccine permissible under Islamic law, and MOH provides it free of charge for citizens. Non-citizen residents, however, face a registration fee and a per-dose charge that places routine immunisation out of reach for low-income undocumented families. Persistent hesitancy also exists in some communities, driven partly by online misinformation about vaccine ingredients — concerns that official religious guidance has not fully resolved at the level of individual parents making individual decisions. A 2023 analysis in BMC Public Health found that no Malaysian birth cohort has achieved 95% effective population immunity since the programme began in 1982, and attributes the persistence of measles in Malaysia specifically to pockets of insufficient coverage. The WHO Western Pacific region — which includes Malaysia — saw measles cases increase 743% between 2022 and 2024, and as of early 2025 Malaysia was specifically named as a country with continued active transmission.
The lesson from both outbreaks is the same. Coverage numbers are averages, and measles does not respect averages. It finds the unprotected fraction.
Bangladesh and the United States arrived at the same epidemiological destination by different routes: one through disruption and gaps in delivery, the other substantially through declining vaccine acceptance. Malaysia offers a third warning — that national averages can conceal local vulnerability. Measles is indifferent to the reason immunity was lost. It needs only enough susceptible people to find one another.
What the Malaysia figures mean for Malaysians travelling abroad — and for families planning to travel with young children or infants — is covered in the companion piece Before You Travel: Measles and the MMR.