In a few weeks, a pivotal meeting of influenza experts from across the globe is set to take place at the Crick Worldwide Influenza Center in London. Led by the World Health Organization (WHO), this multi-day gathering aims to determine the specific viruses that next winter’s flu shot should target. However, a cloud of uncertainty looms over the event as it remains unclear whether representatives from the United States will be in attendance, potentially impacting the composition and efficacy of flu vaccines not only in the Northern Hemisphere but also worldwide.
The decision on which flu vaccine strains to recommend to manufacturers is typically made by the heads of seven WHO influenza collaborating centers and three key regulatory laboratories. Historically, U.S. government agencies have played a significant role in this process, with the Centers for Disease Control and Prevention (CDC) serving as one of the collaborating centers and the Food and Drug Administration (FDA) as one of the essential regulatory labs. However, with the current administration’s plans to withdraw from the WHO and its restrictions on government employees’ interactions with the global health agency, the U.S. participation in this crucial meeting remains uncertain.
Maria Van Kerkhove, acting director of the WHO’s department of epidemic and pandemic threat management, emphasized the importance of the upcoming vaccine composition meeting during a recent press conference. While the CDC and FDA have been invited, there is no confirmation yet on whether they will attend. The Department of Health and Human Services, overseeing both agencies, has yet to provide a response to queries regarding their potential participation.
The process of selecting flu vaccine strains is a meticulous one, as it takes several months to produce, package, and distribute these vaccines. This underscores the significance of experts convening to predict the most prevalent flu strains for the upcoming season while the current one is still ongoing. Kanta Subbarao, an influenza virologist with extensive experience in these meetings, described the deliberations as intense and the work as challenging.
Without the expertise of the CDC and FDA at the table, there are concerns about the potential impact on the effectiveness of next winter’s vaccines and the confusion it may cause for vaccine manufacturers. Moreover, the absence of U.S. representation at the WHO-led meeting could hinder the FDA’s ability to make informed decisions regarding vaccine strains for the U.S. market. Typically, the FDA aligns its selections with those made during the WHO-led meeting.
The uncertainty surrounding the U.S. participation in the meeting extends to the CDC’s data contributions to vital databases managed by the WHO. The halt in sharing influenza data could have repercussions on the decision-making process for selecting vaccine strains. The selection of strains for the seasonal flu vaccine involves an in-depth analysis of various influenza A and B viruses, with a focus on genetic changes and the potential threat these viruses pose in the upcoming season.
As the meeting approaches, the absence of U.S. experts, particularly from the CDC, raises significant concerns among influenza scientists regarding the strain selection process. The potential changes observed in influenza A viruses H1N1 and H3N2 further compound the challenges in predicting the most effective vaccine strains. Danuta Skowronski, a flu expert from the BC Center for Disease Control, emphasized the importance of having comprehensive data and expertise in the decision-making process to mitigate risks associated with selecting vaccine strains.
The strain selection process is inherently complex, requiring a delicate balance of informed decision-making and risk assessment. The involvement of key stakeholders, including the U.S. representatives, is crucial in ensuring the efficacy and relevance of flu vaccines for the upcoming season. The uncertainty surrounding the U.S. participation in the WHO-led meeting underscores the challenges faced in addressing the evolving landscape of influenza viruses and the critical role of global collaboration in protecting public health.
