Dr. Anne Zink, Alaska’s Chief Medical Officer, has recommended not following the idea of ‘herd immunity’ as a strategy to tackle future COVID-19 spikes in Alaska. She discussed the issue during a Thursday evening press briefing with Governor Mike Dunleavy.
Herd immunity is the epidemiological concept that says a sufficient number of people can no longer catch the disease, protecting the rest of the population who has not yet been infected.
For example, if 80% of a population is immune to a virus, four out of every five people who encounter someone with the disease won’t get sick or spread the disease any further. That could keep a lid on future spread of the disease. Measles, mumps, polio, and chickenpox are examples of infectious diseases that were once very common but are now rare in the U.S. because vaccines helped to establish herd immunity.
One method of achieving herd immunity is to allow a spike in the virus to take place to establish a natural immunity while a vaccine for non-infected people is being developed.
Dr. Zink says that exposing more people is a troubling concept, particularly because so many vulnerable Alaskans have not been infected, which could result in deaths as well as overloading our medical resources: “I think what’s really hard about this disease is that we don’t now who all it’s going to affect. We do know that those who are older and more vulnerable are more likely to die. There was a morbidity / mortality review that came from the CDC recently that showed a quarter of all people who are hospitalized in the U.S. from COVID-19 had no underlying health conditions, and were not considered ‘high-risk.’ So, it’s important to realize that while the people who tend to die from this disease tend to have a higher morbidity risk, we’ve seen very young people and very healthy people having very significant consequences from this disease, including hospitalization and stroke, and other significant complications.”
She further said that letting the disease spread like wildfire is a massive risk: “So, I think to just say ‘Let’s just build up herd immunity all at once,’ puts us at real risk for really affecting a lot of Alaskans, overwhelming our health care system, affecting those who are young and healthy as well as those who are older and more vulnerable. That is what we’ve seen in many areas around the world, even while they have tried to control the disease.”
The death rate for COVID-19 is uncertain at this point, but recent data suggests that it is ten times higher than the annual flu. It is even higher still among vulnerable groups like the elderly and people with weakened immune systems
Photo courtesy the Centers For Disease Control.
