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Every year a vaccine is designed to protect against the 3 or 4 influenza viruses determined by surveillance as most likely to spread & cause illness during the upcoming flu season. Many steps in this process are a helpful for perspective with emerging #SARSCoV2 variants
Influenza viruses change constantly (2x faster than coronaviruses)Every year flu vaxx
is reviewed & updated. Updates are based on 1)variants most likely to make people 
2) how well the previous protects vs. new strains & 3) how quickly new strains are spreading.
More that 100 national influenza centers in >100 countries conduct year-round surveillance for influenza! They test thousands of influenza virus samples from patients. Representative viruses are send to 5 WHO Collaborating Centers for Reference and Research on Influenza
2x/ year, WHO consults w Collaborating Centers, Essential Regulatory Labs & key national labs/academies. They review results of surveillance, laboratory & clinical studies, & the availability of vaccine viruses & make recommendations on composition of the flu vaxx.
The WHO recommends specific vaccine viruses for inclusion in influenza vaccines Each country makes their own decision about which viruses should be included in flu vaxx licensed in their country.*This process is seamless and hardly makes the news.
On a very good year the flu is about 70% effective
That protection may wane as the virus evolves during flu season.
Most of the SARSCoV2 are crushing the fluwhen it comes to effectiveness.
the protection they confer appears more stable/durable too (*so far).
#SARSCoV2 variants are expected but should be monitored. 
We will need to update vaccines over time. 
Genomic surveillance like with flu viruses will help guide when.Most current vaccines are still effective vs concerning variants.
Slowing spread helps 
the virus
Each country will decide which vaccines to 
out based on efficacy and circulating variant.Immunizing many and doing it quickly will also helpslow the virus.
Keep calm. We will see more variants over time (remember influenza is doing this too, but its not in the news)
If the latest news on variants makes you nervous
STOP, take a deep breath, mask-up, keep your distance, wash
your hands
and when it's your turn
roll up your sleeve
and get your . 
.FIN
STOP, take a deep breath, mask-up
, keep your distance, wash your hands and when it's your turnroll up your sleeve
and get your . .FIN
