Executive Summary
Data published by the World Health Organization, UNICEF and the Global Polio Eradication Initiative reveal an escalating health and human rights crisis in Yemen. Since 2021, 452 children have been paralysed, with most cases concentrated in the northern governorates, while 96% of the cases recorded by September 2025 involved children under five. This has coincided with the inability to conduct mass vaccination campaigns in the northern governorates since 2022, leaving more than 4.5 million children under five unvaccinated or vulnerable to infection.
The crisis reflects a severe collapse in immunization coverage. National polio vaccination coverage declined from 58% in 2022 to 46% in 2023, while fewer than 30% of children between two and three years of age receive all required vaccine doses. Coverage stands at only 41% for measles, 46% for polio, and 55% for diphtheria, tetanus and pertussis, indicating that millions of children are being denied essential protection against preventable diseases.
Available evidence indicates that restrictions on door-to-door vaccination campaigns, combined with vaccine misinformation and inflammatory rhetoric, have widened the immunity gap and allowed the virus to continue circulating. By contrast, campaigns conducted in government-controlled governorates have demonstrated the capacity to reach more than 1.3 million children in a single round through thousands of mobile and fixed vaccination teams, highlighting a profound geographical disparity in children’s access to preventive healthcare.
SAM considers the obstruction of immunization campaigns and restrictions on the movement of medical teams, despite awareness of the continuing outbreak, to constitute a serious interference with children’s rights to health, life, development and non-discrimination. As the de facto authority in the northern governorates, the Houthi group bears responsibility for removing restrictions, ending vaccine misinformation and ensuring unconditional access for health teams to every child.
The organization calls for an independent investigation into the decisions and practices that have obstructed vaccination campaigns and for accountability for those responsible for preventing access to vaccines or deliberately disseminating misleading health information. It further urges United Nations agencies to adopt a publicly announced access plan, ensure sustainable funding for routine immunization and epidemiological surveillance, and establish specialized programmes to provide treatment, rehabilitation and family support for children affected by paralysis.
Geneva - SAM for Rights and Liberties said that the continued spread of poliovirus in Yemen, coupled with the accumulation of hundreds of cases resulting in permanent disabilities, reveals a prolonged health and human rights crisis. The situation has been exacerbated by the collapse of the healthcare system, declining routine immunization rates, and the inability of mass and door-to-door vaccination campaigns to reach millions of children, particularly in the northern governorates controlled by the Houthi group.
The organization added that restrictions imposed on immunization campaigns, combined with the growing dissemination of rhetoric questioning the safety and effectiveness of vaccines, do not only threaten children living within a specific geographical area. They also allow the virus to continue circulating within Yemen and spreading to other countries, transforming a disease preventable through safe vaccine doses into a cause of permanent childhood paralysis.
SAM stated that Yemen had achieved historic progress in combating the disease, as the World Health Organization confirms that the country has been free of wild poliovirus since 2006. However, in 2020, a new outbreak of circulating vaccine-derived poliovirus type 1 was announced, paralysing 35 children. The outbreak was concentrated in Saada Governorate, where door-to-door vaccination had not been permitted for several years. (World Health Organization)
The organization noted that a joint statement issued by WHO and UNICEF on 11 September 2020 linked the virus’s re-emergence to low immunity levels among children. The statement explained that cases were concentrated in Saada, where routine immunization coverage was extremely low and where the polio programme had been unable to reach children for more than two years. (UNICEF)
SAM indicated that this decline followed years during which comprehensive campaigns had reached millions of children. In 2016, a national door-to-door campaign targeted approximately 5,019,948 children under the age of five and succeeded in immunizing more than 4.5 million children, representing 90% of the target population, with the participation of more than 40,000 health workers. The organization considers these figures evidence that broad access is possible when political will exists and restrictions on medical teams are removed. (World Health Organization)
The organization noted that the Global Polio Eradication Initiative warned in March 2022 of two simultaneous outbreaks of circulating vaccine-derived poliovirus types 1 and 2. It stated that, since 2019, 35 children had been paralysed by type 1 and 14 children by type 2, and that the type 2 virus was expanding and spreading to other countries in the Eastern Mediterranean Region. (Global Polio Eradication Initiative)
SAM pointed out that by 2022, 197 children had been paralysed by circulating vaccine-derived poliovirus type 2 in the northern governorates. This represented approximately one-third of all global cases of this strain recorded during that year. The Initiative also confirmed that viruses genetically linked to the strain circulating in Yemen had been detected in Djibouti, Egypt and Somalia. (Archived Global Polio Eradication Initiative statement)
SAM stated that United Nations data continued to show a gradual increase in the number of cases. UNICEF and WHO reported that Yemen had recorded:
237 cases of circulating vaccine-derived polioviruses between 2021 and 2023.
273 cases of variant polioviruses during the three years preceding October 2024.
SAM reported that the joint statement issued by WHO, UNICEF and the Ministry of Public Health and Population on 30 September 2025 raised the cumulative number recorded since 2021 to 451 cases, with 96% involving children under five. The statement also recorded 29 confirmed cases of circulating vaccine-derived poliovirus type 2 during the first 38 weeks of 2025, including 28 cases in the northern governorates and one case in the southern governorates. (United Nations in Yemen)
SAM added that the most recent United Nations figure identified by the organization appeared in a World Health Organization statement issued on 21 May 2026 and in a subsequent regional update. The cumulative number of children paralysed by circulating vaccine-derived poliovirus type 2 had increased to 452 children since 2021, most of them in the northern governorates. (World Health Organization)
The organization explained that the figures cited in different reports—including 237, 257, 273, 282, 451 and 452 cases—must not be added together or treated as separate cumulative series. They were published on different dates, and some referred specifically to cases of circulating vaccine-derived poliovirus type 2, while others used a broader description of variant poliovirus cases recorded since 2021.
SAM emphasized that the most recent and comprehensive figure published by WHO as of May 2026 is 452 children paralysed since 2021, with the highest concentration of cases remaining in the northern governorates. The figure of 451 cases is the specific number contained in the joint United Nations statement dated 30 September 2025.
SAM noted that the Emergency Committee under the International Health Regulations on the international spread of poliovirus warned on 4 March 2026 that more than 4.5 million children under five in the northern governorates were unvaccinated or otherwise vulnerable to infection. The Committee explained that an adequate oral vaccine response had not been implemented because of insecurity and access difficulties. (World Health Organization)
The organization added that WHO confirmed in May 2026 that no mass vaccination campaign had been able to reach the northern governorates since 2022, leaving millions of children outside the required response and increasing the likelihood of continued virus transmission. (World Health Organization)
SAM stressed that the danger represented by this figure is not limited to children living in those governorates. International transmission of polioviruses linked to the Yemeni strain demonstrates that obstructing the response in one area creates a public health threat to Yemen and the wider region.
SAM stated that the Global Polio Eradication Initiative requires repeated access to at least 90% of targeted children to stop outbreaks of circulating vaccine-derived poliovirus and considers door-to-door vaccination the most effective method for reaching the youngest and most vulnerable children. (Global Polio Eradication Initiative)
The organization noted that the Initiative explicitly called upon the health authorities in Sana’a to permit high-quality door-to-door campaigns. It further explained that, when such campaigns cannot be conducted, intensified fixed-site vaccination should be made available close to communities, accompanied by broad social mobilization led by trusted community and religious figures.
SAM also stated that the Regional Subcommittee on Polio Eradication called on the authorities in the northern governorates to resume door-to-door campaigns and to take urgent measures to confront vaccine-related misinformation, which it said was endangering the lives of thousands of children in Yemen and across the region. (Archived Global Polio Eradication Initiative statement)
SAM noted that UNICEF’s April 2024 report, “Vaccination in Yemen: Saving Lives, Protecting the Economy” found that fewer than 30% of Yemeni children between two and three years of age had received all required vaccine doses. (UNICEF)
The report stated that immunization coverage stood at:
41% for the measles vaccine.
46% for the polio vaccine.
55% for the diphtheria, tetanus and pertussis vaccine.
It also found that Yemen lost approximately 41,000 children in 2022 to diseases that could have been treated or prevented, equivalent to one child dying every 13 minutes. (UNICEF)
SAM pointed out that a joint WHO and UNICEF statement issued on World Polio Day in October 2024 showed that national polio immunization coverage had declined from 58% in 2022 to 46% in 2023. (UNICEF)
SAM also cited UNICEF’s July 2025 statement that 242,000 Yemeni children had missed the first dose of their routine vaccines, and that approximately 39,000 people had died within one year from preventable diseases, equivalent to the death of one child every 13.5 minutes. (UNICEF)
The organization warned that declining coverage does not only lead to infection among unvaccinated children. It also reduces community immunity and allows the virus to reach children who are too young to be vaccinated, those suffering from malnutrition or weakened immunity, and children living in displacement camps and remote areas lacking health services.
SAM stated that United Nations bodies have not limited their analysis to weaknesses in the health system but have repeatedly warned about the impact of misinformation. A statement by the Regional Subcommittee on Polio Eradication described the spread of misinformation and disinformation in the northern governorates as a factor threatening the lives of thousands of children in Yemen and across the region.
The organization noted that media reports documented an event held in Sana’a in February 2023 under the title “The Danger of Vaccines to Humanity,” attended by officials affiliated with the Houthi authorities. The event reportedly included claims describing vaccines as “filth and poisons” and denying that any vaccine is safe. Statements were also attributed to the then health minister in the Sana’a authorities that “vaccination is not compulsory at all” and that anyone requesting it must bear responsibility.
SAM stressed that these quotations originate from media reports rather than United Nations statements. However, they are consistent with official warnings issued by the Global Polio Eradication Initiative and WHO regarding the expansion of vaccine misinformation and hesitancy in the northern governorates.
The organization stated that any authority exercising actual control over media outlets, mosques, schools or health institutions bears heightened responsibility for the information it disseminates, particularly when such information influences decisions that determine whether a child receives protection from paralysis or remains exposed to permanent disability.
SAM stated that immunization campaigns implemented in governorates controlled by the internationally recognized government demonstrated the possibility of reaching large numbers of children through door-to-door campaigns. In February 2024, the campaign targeted:
5,882 mobile door-to-door teams.
845 fixed teams operating from health facilities.
The campaign subsequently reached more than 1.29 million children, achieving overall coverage of 101%, with coverage rates ranging from 89% to more than 100%, depending on the governorate. (UNICEF)
SAM noted that the second round, conducted from 15 to 17 July 2024, targeted more than 1.3 million children in 120 districts across 12 governorates, following the training of approximately 9,000 health workers, supervisors and community mobilizers to reach nearly one million households through door-to-door vaccination. (UNICEF)
The organization added that the July 2025 campaign targeted more than 1.3 million children and was implemented by approximately 7,000 teams, including more than 6,000 door-to-door teams and approximately 800 fixed teams, under the supervision of nearly 2,000 team supervisors and 240 district-level supervisors. (Joint UNICEF and WHO statement)
SAM noted that the Ministry of Health announced that the campaign had vaccinated 1,358,360 children, achieving coverage of 101% of the target, through 6,924 teams, including 6,079 mobile teams and 845 fixed teams, with the participation of 13,003 health workers and supervisors in 120 districts across 12 governorates. (Government-run Saba News Agency)
The organization stated that campaign results demonstrated geographical disparities requiring further intervention. Reported coverage reached 109% in Lahj and Hodeidah, 108% in Marib, 105% in Taiz and 100% in Aden, while declining to 73% in Al-Mahrah and only 43% in Socotra. The operations room therefore recommended extending the campaign in districts that did not achieve the required levels. (Government-run Saba News Agency)
During the second round launched on 29 September 2025, the campaign targeted more than 1.3 million children under five in 12 governorates, involving approximately 15,000 health workers and nearly 1,000 supervisors, operating through door-to-door teams and fixed vaccination sites. (United Nations in Yemen)
According to Ministry of Health figures reported by Yemeni media, 384,873 children were vaccinated on the first day, representing 38% of the target. This included 315,690 children between 12 and 59 months of age, representing 40% of the target for that age group, and 69,183 children under one year of age, representing 31%, in addition to approximately 930 children over five years old. (Source)
SAM emphasized that the success of door-to-door campaigns in some areas, contrasted with the deprivation of millions of children from such campaigns elsewhere, creates a discriminatory disparity in access to preventive healthcare and makes a child’s opportunity for protection from paralysis dependent on their place of residence and the authority controlling it.
SAM stated that UNICEF’s 2024 report affirmed that vaccines prevent more than 4 million child deaths worldwide each year, and that every US dollar invested in childhood immunization may generate an estimated economic return of approximately US$20 in low- and middle-income countries between 2021 and 2030.
The report also stated that vaccination may save families direct expenses amounting to approximately 16 times the cost of the vaccine, by preventing treatment costs, disability and long-term care. (UNICEF)
SAM emphasized that a child’s permanent paralysis does not end with the immediate medical harm. It may deprive a family of a source of income, impose treatment, rehabilitation and assistive-device costs, and affect the child’s ability to receive an education, participate in society and work in the future.
SAM affirmed that basic vaccination is not an optional service granted at the discretion of the authorities. It forms part of the child’s rights to health, life, development and protection from preventable diseases.
The organization noted that Article 24 of the Convention on the Rights of the Child recognizes the child’s right to the highest attainable standard of health and requires appropriate measures to combat disease and ensure that no child is deprived of access to healthcare services.
SAM also referred to General Comment No. 15 of the Committee on the Rights of the Child, which requires health interventions directed at children to be based on scientific evidence and the highest public health standards, while observing the best interests of the child and the principle of non-discrimination.
The organization noted that Article 12 of the International Covenant on Economic, Social and Cultural Rights includes the adoption of measures necessary for the prevention, treatment and control of epidemic and endemic diseases, and the creation of conditions ensuring medical services for all when needed.
SAM explained that during armed conflict, Rule 55 of customary international humanitarian law requires parties to allow and facilitate the rapid and unimpeded passage of relief supplies and equipment essential to civilians. Rule 56 requires freedom of movement for authorized humanitarian relief personnel performing their functions and permits temporary restriction only where required by imperative military necessity.
The organization considers that preventing or obstructing door-to-door vaccination campaigns, confining vaccines to sites inaccessible to poor and displaced families, or disseminating false health information from positions of authority constitutes direct interference with the availability and accessibility of health services. Such conduct may amount to a serious violation of the right to health when it foreseeably results in preventable infections, disabilities and deaths.
SAM stressed that the Houthi group, as the de facto authority in the northern governorates, bears responsibility for ensuring the population’s access to basic health services, refraining from obstructing vaccination teams and humanitarian organizations, and protecting health workers from threats, incitement and interference in their duties.
The organization stated that the continued inability to conduct mass campaigns since 2022, the presence of more than 4.5 million children under five who are unvaccinated or vulnerable to infection, and the concentration of most paralysis cases in the northern governorates are indicators requiring an independent investigation into the decisions and restrictions that prevented the implementation of the internationally recommended epidemiological response.
SAM noted that responsibility is not limited to direct administrative prohibition. It also includes producing or sponsoring rhetoric that generates fear of vaccines, failing to correct false information, and using religious, educational or media institutions to discourage families from immunizing their children.
SAM for Rights and Liberties called on the Houthi group to:
Immediately remove all restrictions on mass and door-to-door vaccination campaigns and allow WHO, UNICEF and their partners to reach children in all governorates and districts under its control.
Permit repeated door-to-door campaigns capable of achieving coverage of at least 90% of targeted children, in accordance with standards established by the Global Polio Eradication Initiative.
End misleading media and religious rhetoric against vaccines and issue a clear official position affirming the safety and effectiveness of vaccines approved by WHO.
Publish epidemiological data regularly and transparently, including numbers of infections, deaths and disabilities, disaggregated by governorate, district, age, sex and vaccination status.
Ensure the safety of vaccination teams and health workers and prevent security or political interference in the selection of personnel, beneficiaries or campaign routes.
SAM also called on the Yemeni government to unify the epidemiological surveillance and data-sharing system, strengthen cold-chain and laboratory capacities, ensure the continuous and free availability of routine vaccines, and avoid relying solely on temporary emergency campaigns.
The organization called on WHO, UNICEF and the Global Polio Eradication Initiative to establish a publicly announced timetable for reaching children in the northern governorates, publish periodic reports identifying areas that vaccination teams were unable to reach and the reasons for the lack of access, and refrain from relying exclusively on general expressions such as “access difficulties” or “security challenges” without identifying the authorities or decisions responsible for the obstruction.
SAM called on international donors to provide sustainable funding for routine immunization, emergency response campaigns, environmental and laboratory surveillance, programmes countering misinformation, and physical therapy and rehabilitation services for children affected by paralysis.
The organization further recommended establishing a national support programme for affected children and their families, including medical treatment and rehabilitation, assistive devices, psychosocial support, inclusive education and financial assistance for families that have lost sources of income while caring for a child with a permanent disability.
SAM called for an independent and transparent investigation into all decisions and measures that resulted in the suspension or restriction of door-to-door immunization campaigns in the northern governorates and into the relationship between those restrictions and the continued spread of the virus since 2021.
The organization stressed the need to investigate organized misinformation campaigns against vaccines, identify those responsible for financing, managing or disseminating them through official, media and religious institutions, and assess their impact on vaccine refusal rates and recorded infections.
SAM affirmed that accountability should extend to any authority or official found to have deliberately prevented vaccines, obstructed medical teams, withheld data or disseminated false information while aware of the serious harm that could result for children.
SAM for Rights and Liberties concluded its statement by emphasizing that the paralysis of 452 children since 2021, the presence of more than 4.5 million children at risk in the northern governorates, and the decline in national polio immunization coverage to 46% in 2023 are not isolated health indicators, but evidence of a prolonged failure to protect children’s rights.
The organization stressed that every new case of paralysis caused by a vaccine-preventable disease represents a child’s life permanently altered. It affirmed that children’s health must not be subjected to political, ideological or security calculations and called upon all parties to guarantee access to vaccines for every Yemeni child, without discrimination, restriction or condition.