Influenza virus sharing is essential to prepare the world against pandemics. Virus sharing also enables the development of candidate vaccine viruses, surveillance for resistance to antiviral medicines, and revision of diagnostic reagents and test kits. Owing to the ongoing conflict in Yemen, the country has been unable to share virus samples every year with the WHO Collaborating Centers under the Global Influenza Surveillance and Response System (GISRS).
However, in May 2024 Yemen succeeded for the first time in shipping the first 50 samples of seasonal influenza viruses to the WHO Collaborating Centre for Reference and Research on Influenza in London, in the United Kingdom. This milestone was made possible by WHO's continuous support to the country over several years.
During the H1N1 pandemic in 2009, Yemen's Ministry of Public Health and Population designated the Central Public Health Laboratories (CPHL) as the National Influenza Centre. Following the COVID-19 emergency, Yemen has adapted its respiratory disease surveillance system to monitor both influenza and SARS-CoV-2 viruses. This was done with support from WHO headquarters and the WHO Regional Office for the Eastern Mediterranean. Since then, Yemen has been expanding its services for the subtyping of influenza and other respiratory viruses to feed into this new national integrated surveillance programme and GISRS.
In March 2022, WHO headquarters and Regional Office experts arranged a mission to Yemen in coordination with the WHO Country Office in Yemen. The mission aimed to reactivate influenza sentinel sites, which had been suspended during the COVID-19 emergency; train Ministry of Public Health and Population and CPHL staff on virus testing and on sharing influenza viruses with human pandemic potential, in line with the Pandemic Influenza Preparedness Framework; and to ensure that CPHL has met the WHO requirements for testing procedures for respiratory viruses.
Since January 2023, samples are being collected at influenza sentinel sites and shipped to the CPHL's governorate-level National Centre for confirmation by polymerase chain reaction (PCR) test. However, until May 2024, logistics constraints prevented the next step of sharing confirmed samples with the WHO Collaborating Centre in London – dry ice, which is needed to ship samples internationally, has been unavailable in Yemen since 2015 due to the war and an embargo.
With support and facilitation from WHO, dry ice was received in Aden, Yemen, from Addis Ababa, Ethiopia, on 13 May 2024. This was transported via a United Nations Humanitarian Air Service flight from Addis Ababa to Aden, and the same plane then took the packaged samples on to Amman, Jordan. The samples safely made the last leg of their journey via international courier from Amman to London, where they were received the next day by the WHO Collaborating Centre for Reference and Research on Influenza for further processing.
The same coordination mechanism will be used for future shipments of influenza virus samples until Yemen can produce dry ice.
