We have each worked on childhood vaccination programs in both development and humanitarian emergency settings for more than 40 years. In that time, we have seen a lot.
The current situation in Gaza is as bad as it gets. According to all reports, and as is visible on our television screens daily, living conditions are atrocious. The basic necessities of life — food, water, and shelter — are difficult to access, and the health system is essentially non-functional. In addition to the horrific toll that weapons of war have exacted on the population, outbreaks of diseases that are preventable under almost all circumstances are inevitable and, indeed, are occurring. Cases of diarrhea, pneumonia, hepatitis, and other infectious diseases are being reported in large numbers, and one can only guess how many people, children and adults alike, have needlessly died.
One case of paralytic poliomyelitis has been confirmed, and hundreds of other children have undoubtedly been infected. In response, the Gaza Ministry of Health, World Health Organization, UNICEF, U.N. Relief and Works Agency, and other partners have managed, against all odds and with unparalleled effort, to mount a vaccination campaign targeting more than 600,000 children under 10 years old with two doses of novel oral polio vaccine in two rounds four weeks apart in an effort to prevent further spread of this crippling disease. They are off to a great start. Demand has been high and the number of children vaccinated in the first few days has exceeded expectations.
Continued success will require attention to countless details: staffing, cold chain equipment, communications, transportation, crowd control, and the many, many other logistical and operational needs of a mass vaccination campaign. Not to mention contingency plans should any of these go wrong.
Despite the high level of preparations and clear early progress, we are surprised and alarmed that there seems to have been little discussion, at least not publicly, of using this opportunity to vaccinate Gazan children against what has long been considered by humanitarian health experts to be the most urgent and most dangerous of the vaccine-preventable diseases in emergency settings: measles.
Measles has been recognized as a major cause of childhood mortality in conflict areas and other humanitarian settings since the late 1970s on the Thai-Cambodia border and the early 1980s in the Horn of Africa. Mass measles vaccination campaigns have long been among the earliest health interventions in emergencies. Measles is one of the most highly transmissible diseases known, with an infectivity rate of almost 100% to non-immune individuals, few sub-clinical cases, and a case-fatality rate as high as 15% in undernourished children. Contrast this with polio, for which only a small fraction of infected individuals will develop symptoms of paralysis and only a small proportion of paralytic cases prove fatal.
Fortunately, as is the case for polio vaccination, over 95% of Gazan children were reported to have been immunized against measles before the current military assault began in October 2023, but after nearly a year of relentless conflict, a significant cohort of unvaccinated children has accumulated. No cases of measles have been reported yet, but with cooler temperatures on the horizon, the narrow window of opportunity during “humanitarian pauses” to access the population to prevent a major outbreak is closing fast — and must be seized.
Because measles is infectious for up to four days before the appearance of a rash, it would be too late to mount an effective outbreak response once it begins spreading in the densely populated Gazan population. Since mortality from measles would be high and since virtually all unimmunized children will be infected, we strongly urge adding measles vaccine to the planned second round of polio vaccination, which will begin in a few weeks.
The good news is that a single measles shot is sufficient to confer long-lasting immunity, as opposed to multiple doses needed for polio. A downside of measles vaccine is that it needs to be injected as opposed to swallowed, as is the case for the oral polio vaccine chosen for use. However, now that the operational and logistical needs of a mass vaccination campaign are in place and, given the smaller target population for a measles campaign (we would recommend vaccinating children from 6 months to at least 24 months of age), we feel that it would be entirely possible to prevent a potentially lethal outbreak from occurring should measles virus be introduced into Gaza in the coming months.
Using oral and injectable vaccines at the same time during campaigns has been standard practice in countless vaccination campaigns, including in conflict settings, for several decades, starting with Days of Tranquility in El Salvador throughout the 1980s. We propose that this is doable by trained health workers, alongside the community volunteers offering the oral polio vaccine.
The polio vaccination campaign is clearly warranted, and we should acknowledge those whose Herculean efforts have allowed it to proceed successfully. They have shown us what can be done even in the most difficult of circumstances.
But copious evidence from decades of experience in responding to the public health consequences of armed conflict and the unconscionable toll that measles has taken in all affected parts of the world when vaccination has been delayed or neglected teaches us that more must be done. To forgo measles vaccination of the children of Gaza would be a grave missed opportunity, a demonstrated failure to learn from the past, and in our view, ethically questionable. The children of Gaza have suffered enough, and it is incumbent upon the public health authorities of the world to do everything feasible to curb the further occurrence of preventable diseases.
Robert Steinglass, MPH, has five decades of public health experience in immunization and vaccine-preventable diseases in 50 resource-poor countries. Phillip Nieburg, M.D., MPH, is an epidemiology and infectious diseases consultant with four decades of experience in domestic and global public health. Ron Waldman, M.D., MPH, has worked in humanitarian health emergencies around the globe, at the U.S. CDC, WHO, Columbia University, and George Washington University.