potted plant near red wooden door
madeleineshort

Are we being unreasonable? (behavior towards omicron)

Welcome 2022! Here’s hoping it’s the final year of this pandemic.

Question: We have adopted a policy that any person who has not been vaccinated would not be allowed to enter our home, on the outside chance that we could expose them to the virus if we are asymptomatic with a breakthrough infection.  Are we being unreasonable?  

Answer: I validate your choice!  

  1. Omicron is extremely contagious.  In an immune naïve population, it’s estimated that 1 person will infect 10 people (e.g. R0 of 10)  This is much higher than the original strain, which had an estimated R0 of 2.5 and much higher than Delta, which had an estimated R0 of just under 7.
  2. Transmission begins before symptoms exhibit. CDC estimates that transmission begins 1-2 days before symptom onset (e.g. presymptomatic phase).  People who remain asymptomatic can also transmit the virus, though scientists estimate that asymptomatic transmission risk is lower than symptomatic transmission risk.
  3. Vaccinated people can experience breakthrough infection. While vaccines continue to protect against severe disease, including hospitalization, they are far less effective at protecting against infection over time and in response to omicron.  
  4. Breakthrough infections can cause onward transmission. The infectious period appears to be shorter among vaccinated individuals who experience breakthrough infection and the risk of onward transmission is lower if a person is vaccinated. Nevertheless, the risk of onward transmission is real. 
  5. Omicron may be milder than Delta, but it is still dangerous for unvaccinated individuals.  We’re still learning about the risk omicron poses to vaccinated and unvaccinated individuals.  Recent data from the UK indicate that ” the risk of presentation to emergency care or hospital admission with Omicron was approximately half of that for Delta.”  Furthermore, “the risk of being admitted to hospital for Omicron cases was lower for those who had received 2 doses of a vaccine (65% lower) compared to those who had not received any vaccination… [and] was lower still among those who had received 3 doses of vaccine (81% lower).”