Shaping global vaccine strategies for zoonotic influenza
Zoonotic influenza viruses, particularly avian and swine strains, continue to pose a significant threat to global health. In response to these emerging zoonotic diseases with pandemic potential, the Food and Agriculture Organization of the United Nations (FAO), working with the World Organisation for Animal Health (WOAH) through their joint initiative, the WOAH/FAO Network of Expertise on Animal Influenza (OFFLU), plays a critical role in global influenza surveillance and response efforts.
Since 2011, FAO and WOAH, through OFFLU, have been contributing to the bi-annual World Health Organization (WHO) Vaccine Composition Meetings (VCMs). These meetings are crucial for assessing and updating candidate vaccine viruses for zoonotic influenza strains, which pose pandemic risks to humans. During the most recent meeting in September 2024, OFFLU provided valuable data on avian and swine influenza viruses that are circulating in animal populations worldwide, bringing crucial insights from the animal health sector to inform public health strategies.
OFFLU's contributions enhance the tripartite collaboration between FAO, WOAH, and WHO, ensuring a coordinated and comprehensive approach to zoonotic disease surveillance. This collaboration involves the efforts of FAO and WOAH country offices, WHO Collaborating Centers (WHO CCs), OFFLU network laboratories, research programs, and global partners. Also, key platforms and databases—such as Global Influenza Surveillance and Response System (GISRS), GISAID, EMPRES Global Animal Disease Information System (EMPRES-i+), and World Animal Health Information System (WAHIS)—facilitate data sharing and reporting.
Monitoring avian and swine influenza trends
Between February and September 2024, 843 outbreaks of avian influenza were reported worldwide, with OFFLU analyzing more than 14,225 sequences of highly pathogenic avian influenza (HPAI) H5 viruses. These outbreaks affected regions including Asia, Europe, Africa, the Americas, and even Antarctica.
In the same period, over 1,009 swine influenza detections were reported globally across 15 countries and three continents. These detections involved 32 different lineages of the virus, highlighting the genetic diversity and ongoing evolution of swine influenza strains.
OFFLU partners were instrumental in collecting and analyzing this data, ensuring swift responses to outbreaks. The data provided by the network allows for a more comprehensive understanding of how these zoonotic viruses evolve and spread. This is essential for identifying appropriate candidate vaccine viruses, which in turn are crucial for pandemic preparedness and response.
After consultation, WHO proposed three new CVVs. A/Cambodia/SVH240441/2024-like CVV for Gs/Gd lineage clade 2.3.2.1c viruses, A/Jiangsu/428/2021-like CVV for H10 viruses, and A/Pennsylvania/27/2024 CVV for H1 clade 1A.1.1.3 variant viruses.
Fostering international collaboration on zoonotic influenza
OFFLU's role extends beyond data collection and analysis—it serves as a platform for fostering international collaboration between laboratories, research institutions, and government agencies. This cooperative approach enables member states to share critical epidemiological and genomic data, ensuring that health experts have the most up-to-date information to monitor and address zoonotic threats. This strengthens both animal and human health policies, reinforcing the importance of the One Health approach.
Through the joint efforts of FAO, WOAH, and WHO, significant progress has been made in understanding the antigenic diversity of influenza viruses, leading to more targeted vaccine recommendations. FAO’s contributions ensure that timely, effective vaccines are developed, minimizing the impact of these viruses on both animal and human populations.