EYE Strategy October newsletter 

Yellow fever vaccination campaign, Cameroon. May 2022

News release: EYE Strategy mid-term evaluation report 

Since 2017, according to EYE Strategy data, 248* million more people in Africa have been protected via yellow fever campaigns via a single-dose vaccine that provides lifelong protection. As a comparison, under the previous Yellow Fever Initiative, 105 million people were protected in an 8-year period. The EYE Strategy’s global coalition has contributed to the acceleration of vaccination during this period. 

“The EYE Strategy has worked closely with Member States and communities through integrated programmes to rapidly respond to outbreaks of yellow fever. This has been done through enhancing vaccine coverage, surveillance, and diagnostics to curb the deadly impact of this disease in Africa and the Americas,” says Dr Mike Ryan, Executive Director of WHO’s Health Emergencies Programme. “We have seen a resurgence of outbreaks of this disease in previously immunized areas, with risk in urban centres, which tells us the threat is far from over. Evidence shows that we are on the path to eliminating yellow fever epidemics, but our work is not yet done.”   

To read the full news release, please click here.  

*The current estimate of 248, 448, 430 people vaccinated includes estimates based on target population, preliminary reported numbers and admin coverage. 

Country updates 

Guinea 

Image: Field discussions for a root cause analysis workshop, Guinea. October 2023 

In October 2023, Guinea conducted a root cause analysis into yellow fever epidemics, which have occurred despite a history of mass vaccination campaigns in the country. This analysis included an evaluation of the delays in yellow fever outbreak response, and their causes.  

Guinea is the first country to have conducted an in-depth evaluation using a tool developed by WHO and TDR (For research on diseases of poverty) in collaboration with WHO Health Emergency Interventions (HEI) Department and the EYE Strategy technical working groups. The results of these analyses seek to enable an action plan to prevent future outbreaks.  

Alongside this, a yellow fever immunity gap analysis was conducted using a new tool. The tool seeks to identify priority districts and provide estimates of unprotected populations. This data will then form part of a catch-up vaccination plan to be implemented nationally. The target population is five- to 59-year-olds and will be complemented by a catch-up campaign for children of five and under. 

Results from the root cause analysis, evaluation of delays in outbreak response, and immunity gap analysis were presented and discussed at a workshop held on 25th October in Conakry. 

Reactive Vaccination Campaign (RVCs) 

Central African Republic (CAR) 

CAR conducted its RVC from 28th September to 2nd October 2023, targeting ~231,000 people aged nine months to 60 years, which included a population of high-risk workers (including seasonal workers and miners) and the ethnic minority group, pygmies. RVC also had a specific focus on determining recipients of the vaccine based on gender. The split was roughly 50% male and 50% female.  

Preventive mass vaccination campaigns (PMVCs)   

The Democratic Republic of the Congo (DRC)       

Yellow fever vaccination campaigns that were combined with measles round 1 have now been completed in Lomami, Kasai, and Central Kasai. Kasai Oriental was completed earlier this year. Further PMVCs are due to take place in Kongo Central, Kwango, Kwilu, and Mai Ndombe before the end of 2023 and will target almost 12 million people. 

Some districts in Kongo Central, Kwango, and Lualaba had completed an RVC during the Angola outbreak in 2016. Immunization gaps in these provinces are still being investigated. Two further provinces of Ituri and Nord Kivu are planned for 2024.  

Nigeria 

Nigeria has completed RVCs and PMVCs in 34 of its 37 states. The states of Yobe, Lagos and Pachabo are planned for 2024. 

Yellow fever vaccine allocation for 2024

2024 yellow fever vaccine allocation map

Five countries (Chad, DRC, Niger, Nigeria, and Uganda) have been confirmed for the 2024 allocation of vaccine for PMVCs. Approximately 62.8 million doses (MDs) have been confirmed (conservative estimates). Vaccines were allocated as follows:

1. Nigeria was allocated 24.2 MDs. This will enable coverage of its remaining states (including Borno and Lagos) in the final phase of the PMVCs and nationwide coverage.
    
2. Chad was allocated 18.4 MDs toward nationwide coverage in 2024.
    
3. DRC was allocated 10.3 MDs to protect populations of the Nord Kivu province.
    
4. Niger was allocated 5.3 MDs to initiate multi-year campaigns and the full coverage of two regions where confirmed cases have been reported since 2022 (Agadez and Maradi).
    
5. Uganda was allocated 2.4 MDs to continue multi-year campaigns. 

He is a former official of the Ministry of Health of Peru, where he worked on the surveillance of VPDs. He was also Deputy Chief and Acting Chief of the National Institute of Health of Peru, during which time yellow fever vaccination campaigns were implemented.  

He has worked as a consultant in epidemiology and public health for eight years in national and international institutions, conducting scientific research, training, and developing technical proposals for the surveillance and prevention and control of diseases including yellow fever, HIV, hepatitis B, and influenza.  

Dr Whittembury is a former PAHO/WHO staff member in Ecuador, where he worked as Immunization Adviser; a professor at the National University of San Marcos in Peru, and in postgraduate programs at Cayetano Heredia University.  

Dr Whittembury has been serving as Immunization Advisor in the PAHO/WHO Comprehensive Immunization Program (CIM) in the Regional Office in Washington DC, with responsibilities that include yellow fever vaccination. 

Ending disease in Africa: responding to communicable and noncommunicable diseases, progress report 2020-2022   

Key messages from the report:  

• The African Region continues to bear a heavy burden of tropical and vector-borne diseases, with climate-sensitive and epidemic-prone arboviruses becoming increasing public health threats. From 1st July 2021 to 30th June 2022, 13 countries reported new yellow fever outbreaks. 

• By the end of 2022, almost all yellow fever high-risk countries had introduced routine yellow fever vaccination at the national level. Most priority countries have conducted a PMVC against yellow fever or are in the process of doing so. Over 174 million people have been protected through mass vaccination campaigns since 2017. In addition, more than 4 million people were vaccinated during reactive vaccination campaigns conducted in five countries during 2021 and 2022 as part of outbreak response.  

• Yellow fever surveillance has been integrated as part of epidemic-prone disease surveillance and vaccine preventable disease surveillance system. 

• In 2021, estimated routine childhood immunization coverage against yellow fever in the African Region was 48%, much lower than the 80% threshold required to confer population immunity. 

• To date, the region has three accredited yellow fever regional reference laboratories with fully functional confirmation capacity (Pasteur Institute of Dakar, Senegal; Centre Pasteur du Cameroun, Cameroon; Uganda Virus Research Institute, Uganda). The National Reference Laboratory in Abuja, Nigeria has been accredited for serological and molecular diagnostics. 

To read more about the challenges and priorities of the EYE Strategy, and the full report on all communicable and non-communicable diseases in Africa, click here.