related_tweet: vaccines less effective against variant strains of covid-19 (delta, alpha etc.) 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  they reduce severity of illness, but asymptomatic transmission is still possible. it's important to still wear masks, practice social distancing when encountering immunocompromised persons