Dr Mutahar Ahmed, R, reviewing the location of AFP cases with Dr Khaled Al-Moayad, Director of Disease Control and Surveillance in Sanaa, Yemen © Omar Nasr / WHO Yemen
Dr Mutahar Ahmed, R, reviewing the location of AFP cases with Dr Khaled Al-Moayad, Director of Disease Control and Surveillance in Sanaa, Yemen © Omar Nasr / WHO Yemen

At his office in Sana’a, Yemen, Dr Mutahar Ahmed stands before a wall-sized map of his country and feels the weight of the world on his shoulders.

“The situation here in Yemen is very complex, and the problems we face are quite immense,” said Dr Ahmed.

As Yemen’s national surveillance coordinator, Dr Ahmed leads the country’s acute flaccid paralysis (AFP) surveillance efforts, the primary means of tracking poliovirus transmission. With an explosive outbreak of circulating vaccine-derived poliovirus type 2 having paralysed 115 children and counting, and with swathes of the country’s infrastructure – from roads to hospitals – decimated by conflict, you’d be forgiven for thinking that his and his team’s efforts to surveil for poliovirus were falling short or otherwise compromised. But you’d be wrong.

In Yemen, despite a long-running conflict and complex humanitarian disaster that has significantly impacted health care, AFP surveillance indicators tell a promising story of a functioning system where case detection, sample collection and laboratory analysis – the steps that enable us to detect poliovirus so we can respond to it – are, in fact, on track.

Surveillance data allows the polio programme to identify new AFP cases and to test those cases to determine whether polio infection is the cause. In this way, a robust and wide-reaching AFP surveillance system enables health workers to detect the presence and circulation of poliovirus.

Dr Mutahar Ahmed, national surveillance coordinator, at a health facility in Sanaa, Yemen. © Omar Nasr / WHO Yemen
Dr Mutahar Ahmed, national surveillance coordinator, at a health facility in Sanaa, Yemen. © Omar Nasr / WHO Yemen

“In addition to our work building the engagement and knowledge of pediatricians and clinicians, we are reaching the community and community-based health care providers including traditional healers. We also appeal to families for their support in reporting cases. The more aware they are of the symptoms of paralysis in a child, the quicker our surveillance coordinators can collect the stool sample for analysis,” said Dr Ahmed.

Early detection of symptoms such as AFP is a crucial step in the chain of polio surveillance. If a case of paralysis is not reported within the first 14 days of the onset of symptoms, the reliability of testing the sample in the lab reduces significantly. In Yemen, the AFP surveillance system in high-risk districts is supported by volunteers trained in community-based surveillance. In 2021, 82% of AFP cases were detected early, within the first seven days of the onset of paralysis, which is above the global target of 80%.

Once a case is detected and stool samples are collected, it’s vital to make sure the samples reach the laboratory in good condition.

“Two stool samples are required from each child showing symptoms of paralysis. Both samples need to be collected within the first 14 days, 24 hours apart. They need to be correctly labelled, and their temperature needs to be maintained at between 2 and 8 degrees. Otherwise, they are not adequate samples,” said Dr Ahmed.

In 2021, 921 AFP cases were detected. Of these cases, 87.84% had adequate specimens collected, which is above the global target of 80%.

Along with stool adequacy, another key performance indicator for surveillance is the non-polio AFP rate. This refers to the detection of diseases, other than polio, that can cause AFP. Yemen’s non-polio AFP rate is 5.96 per 100,000 children aged below 15 years in 2021, significantly higher than the global standard of three per 100,000 for polio outbreak countries like Yemen. This accomplishment points to the sensitivity of Yemen’s surveillance system due to the relentless efforts and commitment of the surveillance personnel working with Dr Ahmed.

Dr Mutahar Ahmed, L, inspecting samples with Dr Abdullah Yahya, assistant national coordinator for AFP surveillance © Omar Nasr / WHO Yemen
Dr Mutahar Ahmed, L, inspecting samples with Dr Abdullah Yahya, assistant national coordinator for AFP surveillance © Omar Nasr / WHO Yemen

Due to electricity shortages, maintaining the cold chain (keeping vaccines cold) and reverse cold chain (keeping stool samples cold) poses a significant challenge for the programme. To overcome this and further increase the efficiency and sensitivity of the surveillance system to detect polioviruses as quickly as possible, solar power panels have been installed in health facilities at the central and governorate levels to support the storage and transfer of stool samples. One indicator of the impact of this change is Yemen’s non-polio enterovirus rate, which tells us what percent of stool samples tested negative for poliovirus, but were in such condition that they could still test positive for enteroviruses. In 2021, that rate was 20 percent above the global target of 10 percent.

Because Yemen does not have a poliovirus laboratory in-country for testing, samples are first collected at the central level in Sana’a and then sent by road to Muscat, Oman. The journey can take up to seven days, barring any obstacles or emergencies.

“Working in this role is a challenge, but what I particularly enjoy is how we are able to turn these challenges into opportunities for the AFP surveillance programme. The AFP indicators for the last year show us how far we have come in our journey,” said Dr Ahmed.

He explained why these indicators are so critical to the polio programme.

“The fact that our indicators are above the minimum global standards shows that the surveillance system is functioning, sensitive and responsive, despite the critical humanitarian situation. The data from our surveillance work has helped us identify the outbreak of circulating vaccine-derived polioviruses type-1 and type-2. The situation is quite fragile, but we are committed to addressing these challenges, and we will continue to do so.”

WHO has supported Yemen to establish an environmental surveillance system to supplement its AFP surveillance system and support early detection of polioviruses and more timely responses.

Dr. Nabil vaccinating administering polio drops to one of his grandsons in front of the community to convince people about the safety of the polio vaccine. © UNICEF Yemen
Dr. Nabil vaccinating administering polio drops to one of his grandsons in front of the community to convince people about the safety of the polio vaccine. ©UNICEF/Firdous

It’s been a long day for Dr. Nabeel Abdu Omar Ali. Since early morning, he has been going from  one house to the next in a community in Aden, Yemen – listening to the concerns of parents and speaking to them about the importance of vaccination to save their children from polio. And he plans to continue till the sun goes down.

“The weather is pleasant now and I want to meet as many parents as possible, especially those who have concerns about vaccines. In a month’s time, the heat and humidity will be unbearable, making it difficult to walk from house to house,” says Dr. Nabeel.

Nicknamed “the mobile imam” by his peers, Dr. Nabeel is a pediatrician by profession, and a certified imam (Islamic teacher) from the Ministry of Endowment in Southern Yemen. He uses his religious knowledge and medical facts to educate the public about the importance of vaccination in protecting children from polio and other deadly diseases.

A few weeks back, he visited several families who were refusing vaccines in a nearby neighborhood. In addition to speaking to them about the safety and benefits of the polio vaccine, the ‘mobile Imam’ administered polio drops to his grandchildren in front of everyone at the community meeting.

“When the people saw a doctor and Imam like me vaccinating my own grandchildren, I think it was easier for them to believe that the vaccine was safe for their children too,” says Dr. Nabeel with a smile.

Reaching out to other Imams for support 

Dr. Nabeel frequently reaches out to other Imams, training them about the benefits of vaccination and encourages them to share with the public during their Friday sermons.

Dr. Nabeel accompanying a polio vaccination team from one house to the next to speak with parents and caregivers. © UNICEF Yemen
Dr. Nabeel accompanying a polio vaccination team from one house to the next to speak with parents and caregivers. ©UNICEF/Firdous

“Imams are very influential in our communities – to raise awareness, shape social values, and promote positive attitudes, behaviours and practices. For example, a single sermon is powerful enough to change misconceptions about vaccines in some communities. If Imams are fully equipped with accurate information, it goes a long way in build trust and creating vaccine acceptance among the people – helping children in the community to stay health and free from polio and other vaccine-preventable diseases,” he adds.

The ongoing conflict in Yemen has severely damaged the health and basic infrastructure. There are frequent interruptions in power supply, and this often creates suspicion among community members as well as Imams whether vaccines are being stored safely.

“I was training a group of imams and they shared their doubts about the safety of the vaccine. They were skeptical about how refrigerators could store polio vaccines safely when there are so many power cuts in the area.”

In response, Dr. Nabeel organized a tour for the group to a vaccine storage facility where they were able to see and learn about special refrigerators that are powered by solar energy when there are power cuts.

Promoting the benefits of vaccination for over a decade

Dr. Nabeel has been working for the immunization programme in Yemen for over 12 years, partnering with UNICEF for numerous polio vaccination campaigns and routine immunization services.

When he first started out as pediatrician, he met many children who were paralyzed by polio. He felt frustrated that so many children would have to suffer for the rest of their lives by a disease that could have been easily prevented by a vaccine. That is when he decided to dedicate his time to educate caregivers and parents on the benefits of vaccination.

Dr. Nabeel (third from left) speaking with male members of a local community on the benefits of vaccination for children’s health and well-being. Photo: ©UNICEF Yemen
Dr. Nabeel (third from left) speaking with male members of a local community on the benefits of vaccination for children’s health and well-being. Photo: ©UNICEF/Firdous

“There are many misconceptions about vaccines. Throughout my career I have been confronted by people who were resistant to the idea of vaccination. Some people think that the vaccine will make them infertile, while others believe it’s some kind of a conspiracy.  However, my many years of work in immunization and knowledge of religious scriptures has proven to be valuable so far in building trust in vaccine in communities,” says Dr. Nabeel.

The ‘mobile Imam’ is also quite adept in working with the media to promote vaccination. He is often seen and heard on TV and radio talk shows speaking about the benefits of vaccination and answering to questions from concerned parents and caregivers.

“I use a mixed approach to address vaccine hesitancy and dispel misinformation about vaccines. Sometimes it is helpful to talk about vaccines during Friday sermon, while other times, it is more effective to explain to a caller on a radio programme why vaccines are important,” he explains with a smile.

Yemen is currently experiencing twin outbreaks of circulating vaccine-derived poliovirus type 1 and type 2 (cVDPV1 and cVDPV2). Both strains of poliovirus emerge in populations with low immunity and both can result in lifelong paralysis and even death.

Since 2019, 35 and 14 children have been paralysed by cVDPV1 and cVDPV2 respectively, three of the cVDPV2 cases confirmed in the past 10 days alone. The cVDPV2 outbreak, in particular, is ongoing and expanding and has already spread to other countries in WHO’s Eastern Mediterranean Region and UNICEF’s Middle East and North Africa Region.  At its fourth meeting on 9 February 2022, the Eastern Mediterranean Ministerial Regional Subcommittee on Polio Eradication and Outbreaks issued a statement, expressing deep concern around these expanding outbreaks and requesting all authorities in Yemen to facilitate resumption of house-to-house vaccination campaigns in all areas.

The Global Polio Eradication Initiative (GPEI) partners strongly recommend high-coverage mass vaccination campaigns to stop a cVDPV outbreak.  The vaccination response must achieve at least 90% of children vaccinated repeatedly with polio vaccine to protect them from polio and prevent seeding new vaccine-derived emergences. Therefore, the guidelines in the Polio Outbreak Response Standard Operating Procedures recommend that the vaccination response to polio outbreaks should be conducted using the house-to-house vaccine delivery strategy to maximize coverage of vulnerable children.

The GPEI urges the health authorities in Sana’a to conduct high quality house-to-house vaccination campaigns to stop the two concurrent outbreaks as soon as possible. If the current conditions in parts of Yemen do not permit house-to-house vaccination, then an intensified fixed-site vaccination campaign with appropriate social mobilization by the community and religious leaders trusted by the local communities should be implemented to maximize coverage among all vulnerable children.

Yemeni children face no shortage of threats: prolonged conflict, a devastated healthcare system, hunger and disease. But polio is one disease that can easily be prevented. Its circulation can be stopped in Yemen or anywhere else by vaccinating all children with oral polio vaccine.

The GPEI partners – WHO, Rotary International, the U.S. Centers for Disease Control and Prevention, UNICEF, the Bill & Melinda Gates Foundation and Gavi – are committed to providing support to all stakeholders in Yemen for responding to the polio outbreaks including in conducting polio vaccination campaigns that can reach all vulnerable children.

Cairo, 10 February 2022 – The fourth meeting of the Regional Subcommittee on Polio Eradication and Outbreaks was convened on Wednesday 9 February, by WHO’s Regional Director for the Eastern Mediterranean Dr Ahmed Al-Mandhari. The meeting was attended by health ministers or their representatives from Djibouti, Egypt, the Islamic Republic of Iran, Pakistan, Qatar, Saudi Arabia, Sudan, United Arab Emirates and Yemen.

The Subcommittee declared the ongoing circulation of any strain of poliovirus in the Region to be a regional public health emergency and called on all authorities to enable uninterrupted access to the youngest and most vulnerable children through the resumption of house-to-house vaccination campaigns. It issued statements on wild poliovirus circulation in Afghanistan and Pakistan and on the circulation of vaccine-derived poliovirus strains in Yemen, where limits on house-to-house vaccination are preventing access to the most vulnerable children.

The spread of polio in the Eastern Mediterranean Region is a pressing emergency and it remains a Public Health Emergency of International Concern (PHEIC) under the International Health Regulations (IHR 2005).

Members noted a sharp decrease in cases of wild poliovirus in Afghanistan and Pakistan in 2021 but warned against complacency.

“Wild poliovirus transmission is at a historic low in the endemic countries of Afghanistan and Pakistan. The progress is remarkable, but it is fragile. The opportunity to end polio is knocking at our door, and we must seize it,” said Dr Al-Mandhari.

Speaking to the progress made in the last year, the Special Assistant to the Prime Minister on Health, Dr Faisal Sultan, assured members that the programme in Pakistan was leaving no stone unturned in the pursuit of zero polio transmission.

“We have intensified efforts in the hardest districts and core reservoirs and we are closely monitoring transmission across the border in coordination with Afghanistan, taking measures to respond to outbreaks if they occur and making every effort to ensure that the virus doesn’t spill over in either direction. To boost the confidence of marginalized communities, we are also providing essential services and vaccination of other antigens and diseases,” he said.

Outbreaks of circulating vaccine-derived polioviruses type 1 (cVDPV1) and type 2 (cVDPV2) continued to emerge and spread in the Region in 2021. As of February 2022, Afghanistan, Djibouti, Egypt, Pakistan, Somalia, Sudan and Yemen are responding to transmission of vaccine-derived polioviruses.

“The increasing outbreaks of circulating vaccine-derived poliovirus type 2 in the Eastern Mediterranean Region and neighbouring countries of Africa are deeply concerning and must be stopped rapidly. To do so, we need to ensure that we are creating an enabling environment for health workers to reach children with those two drops of polio vaccine,” said newly nominated co-chair H.E. Dr Hanan Mohamed Al Kuwari, Minister of Public Health of Qatar.

During the meeting, Djibouti’s Public Health Minister, Dr Ahmed Robleh Abdilleh, shared plans for vaccination campaigns and increased surveillance in response to the transmission of cVDPV2, recently detected through the newly launched environmental sampling programme.

Reflecting on the work of the Subcommittee, co-chair and Minister of Health and Prevention of the United Arab Emirates H.E. Abdul Rahman Mohammed Al Owais urged members to sustain the commitment seen in in 2021.

“We have together advocated for an increase in domestic funds, we have driven collaborative public health action in our own countries, and collectively pushed for a regional response to address the regional public health emergency of the poliovirus. But these things alone will not end transmission,” he said.

Dr Al-Mandhari expressed appreciation for Egypt’s role as the first country in the Region to roll out a nationwide vaccination campaign using the novel poliovirus vaccine, and Chris Elias, Chair of the Polio Oversight Board, praised the remarkable progress made in polio eradication in Pakistan with support of the United Arab Emirate’s Pakistan Assistance Programme.

“This regional solidarity and commitment we have seen, through this Subcommittee, is something I am proud of. It is this commitment to the end goal that will help push us over the last mile,” said Dr Hamid Jafari, director of the regional polio programme and co-facilitator of the Regional Subcommittee.

Mass polio vaccination campaign to prevent outbreaks

A Yemeni child receives oral polio vaccine during the November vaccination round. WHO
A Yemeni child receives oral polio vaccine during the November vaccination round. WHO

As long as poliovirus continues to circulate anywhere, it threatens children everywhere. Yemen has taken this message on board, ensuring the country’s children are protected against polio by holding a nationwide vaccination round this month. Funding for the campaign included a grant from the Kingdom of Saudi Arabia.
Yemen, which has been polio-free since 2009, is considered to be at high risk of reinfection with poliovirus, as recent instability has led to decreasing access to social and healthcare services, including vaccination for children. Yemen is also threatened by the possible international spread of poliovirus from the Horn of Africa region and continued intense transmission in Chad and northern Nigeria. The country suffered from a severe outbreak of polio in 2005, following the importation of poliovirus of northern Nigerian origin, paralysing 478 Yemeni children.

Heeding the lessons of the past, the country launched National Immunization Days (NIDs) on 14 November at a ceremony hosted by Vice President Abd-Rabbu Mansour Hadi. More than 40,000 health workers were mobilized, aiming to vaccinate more than four million children under five years of age over four days. Prior to the vaccination round, public service message were broadcast on television and radio, posters and banners were widely distributed, and around 3,330 Imams were brought on board to inform Yemeni parents of the importance of vaccinating their children.

While a full analysis of the round is still being compiled, initial reports tell of “unprecedented cooperation and support from communities and local authorities in most part of the country”. By the third day of the campaign, more than 3.7 million children had already been immunized.

In addition to conducting National Immunization Days, countries at risk of polio re-infection, like Yemen, should continue to ensure that their acute flaccid paralysis (AFP) surveillance system is well functioning and able to detect poliovirus importations, and routine immunization coverage is increased.

Yemen is planning to conduct another round of National Immunization Days in early December.