Over the past week, around 50 influenza scientists from various countries have gathered at a Hilton hotel in Istanbul, Turkey, to devise a next-generation flu vaccine set to offer the best protection for the upcoming flu season beginning in fall 2026. These experts have been meticulously analyzing extensive data regarding the virus’s evolution worldwide, evaluating last year’s vaccine efficacy, and identifying which strains could be most viable for mass production.
The World Health Organization (WHO) hosts this vital meeting, part of its Global Influenza Surveillance and Response System, biannually. Dr. Dan Jernigan, who previously led the CDC’s National Center for Emerging and Zoonotic Infectious Diseases, described the process as “really tedious,” emphasizing the necessity of thorough review to make informed vaccine choices.
Despite uncertainties following the U.S. withdrawal from the WHO in January, the Biden administration confirmed earlier this month that the CDC would participate in the meeting virtually. The Department of Health and Human Services stated that the agency’s involvement would focus on providing technical expertise and contributing to scientific discussions regarding vaccine strain recommendations.
Epidemiologist Jennifer Nuzzo, director of the Pandemic Center at Brown University, highlighted the significance of these international collaborations for effective public health measures. She noted that, despite political changes, the reality is that the safety and health of the nation rely on global cooperation.
Historically, the CDC has played a crucial role in these meetings; however, the withdrawal of the U.S. from the WHO could diminish its influence in determining which flu strains are prioritized for vaccines. The WHO’s surveillance system, crucial in tracking flu viruses globally, collects data year-round from infected individuals across 130 countries. These samples are then analyzed by seven WHO collaborating centers, including the CDC. The system’s efficiency relies on a steady flow of samples, which has faced disruptions due to budget cuts following the U.S. exit.
Maria Van Kerkhove, WHO’s interim director of epidemic and pandemic threat management, acknowledged challenges in maintaining sample flow, saying there was a slight dip in flu vaccine circulation due to funding issues. Although recent efforts have resumed shipments globally, there are concerns about the long-term sustainability of this system.
The lack of U.S. officials able to engage directly in discussions is another significant deviation from tradition. Dr. Jernigan pointed out that the collaborative nature of these meetings is essential for objectivity and data-driven decision-making regarding vaccine strains. With U.S. representatives participating only virtually, the dynamics may shift, potentially impacting the selection of strains that align with current trends in the United States.
Tomorrow, the WHO will announce its recommended strains for next year’s flu vaccine, after which manufacturers will begin the nine-month production process. Dr. Ali Khan, dean of public health at the University of Nebraska, emphasized that the collaborative nature of this effort is reassuring; nevertheless, he noted ongoing concerns about the diminishing influence of the U.S. in global health discussions.
The cooperative spirit of this global assembly, notwithstanding political challenges, offers hope for a robust response to influenza threats in the upcoming season. Together, these scientists are addressing a critical public health issue, aiming to fortify defenses against a virus that affects billions of individuals each year.