THREAD: One risk of decision to pull out of WHO, and its intersection with Covid, relates to the Global Influenza Surveillance and Response System, started 70 years ago to provide early warning of flu viruses circulating globally and mitigate pandemic risk ncbi.nlm.nih.gov/pmc/articles/P…
GISRS is a network of about 150 international labs in 114 countries that collect flu specimens for sequencing to allow us to get an early warning on new circulating flu strains and track global prevalence. This effort is key to selection of strains for the annual flu vaccine. 
Trevor Bedford, who participates in this effort, gives an excellent overview of the critical contributions here @trvrb
As Trevor observes, this network sequenced and shared over 28,000 viruses via @GISAID in 2019, allowing researchers at @nextstrain to track viral evolution and forecast emerging strains at nextstrain.org/flu. The process is key for selecting strains for annual flu vaccines.
WHO enables communications between GISRS laboratories. Another example of this is the FluNet platform, an electronic database that allows GISRS laboratories to upload lab and epidemiological data. This network was launched 20 years ago.
In months leading up to biannual Vaccine Consultation Meetings, WHO Collaborating Centers exchange viruses, reagents, and information on flu strains. The meetings are held twice a year. The Feb meeting makes recommendations for Northern Hemisphere, Aug for the Southern Hemisphere
The GISRS is key for monitoring flu and developing vaccines targeted to prevalent strains. We need a similar network for Covid. It'll likely sit on top of GISRS. But how will U.S. support this mission? It's a critical need as Covid evolves, and we’ll need to update vaccines.
We'll need to quickly develop a way to support the GISRS and expand it to cover SARS-CoV-2 so that we are actively tracking the genetic drift that Covid is likely to undergo and make sure our vaccines for influenza and Covid remain up to date and best target the prevalent strains
