September 2, 2020

Galloping herd

Today I saw one of my favorite patients. Well, actually it was a video visit, so she would not need to risk coming into the clinic. I only became her doctor a few years ago when her prior doctor retired, but I treasure the relationship we have developed. She uses a wheelchair due to scoliosis and muscle weakness that developed after having polio many years ago. She was not always in a wheelchair, but developed post-polio syndrome decades later which caused severe weakness in her muscles in her legs and spine. It has also caused weakness in her muscles that help her breathe so she is at risk if she were to get exposed to SARS-CoV-2. Post-polio syndrome sucks, but she bears it with dignity and a wicked sense of humor.

Post Polio Syndrome effects as many as 40% of people who had polio and comes on decades later, causing severe fatigue and muscle weakness among other things. I am betting that most of you have never heard about it, because polio was essentially eradicated in the US when vaccines were introduced starting in the 1950’s.

And that is why I worry about the new attention being paid to “herd immunity”. Herd immunity is when enough people in a community or population are immune to a disease so that if exposed they don’t catch the disease and thus can't transmit it further. There are estimates flying around about what percentage of our population needs to be immune to stop the spread of SARS-CoV-2, and the answer is not clear.

The two main ways to get to Herd Immunity are:

A. Increase number of infections so most people get infected to reach the threshold to stop transmissions;

or

B. Vaccinate a high enough percentage of the population so it can’t spread.

Simplistically, reaching herd immunity through infections seems like a reasonable idea. It can help us open up the economy and open up society again. Sweden tried this by keeping their economy and society open, hoping to reach herd immunity. It didn’t work out as they hoped. Sweden had the highest number of infections and deaths in the nordic countries and their economy suffered despite keeping things open.

But the United States is not Sweden. We have much higher rates of pre-existing high risk conditions, like obesity and diabetes, that put our citizens at risk of death. Already we have 4% of the world’s population and 25% of the deaths. The obesity epidemic has put our citizens at higher risk than many countries. Reaching herd immunity through increased infections would cause untold suffering and death, while overwhelming the health care system. Some estimates say this policy could lead to as many as 1 million deaths. This dangerous idea of reaching herd immunity through having more people get infected is being pushed by a new advisor to our president, a neuro-radiologist, who has not been trained in epidemiology or infectious diseases. He has spent his career reading MRI’s and other studies of the brain and nervous system, until he became a member of the Hoover Institute, a conservative think tank, and a health advisor on Fox News. Dr. Fauci, an infectious disease doctor, trained in epidemiology and public health, does not agree with this idea, because he sees the great costs it would bring to patients, families, and the medical community. I am sticking with Dr. Fauci.

And I am also thinking of my patient today with post-polio syndrome, suffering effects from a disease she had decades ago. I think about other patients with “long-covid” symptoms, who are suffering now from their infections. We do not yet know the long term consequences of COVID-19, so I will not shoot for herd immunity until we have a safe vaccine. We already have too much grief and suffering that is being dismissed by many in our president’s party. Heartbreaking to the families who have suffered loss.

Wash your hands, cover your nose, keep safe six, and remember herd immunity is coming. Advocate for a safe and effective vaccine.

And finally, my caveat is that this is my experience and my opinions, which are subject to change as more information is available, and not related to the organization I work for. Thanks for reading.

https://www.medpagetoday.com/infectiousdisease/covid19/88401

https://en.wikipedia.org/wiki/Post-polio_syndrome

https://www.mayoclinic.org/diseases-conditions/post-polio-syndrome/symptoms-causes/syc-20355669

https://en.wikipedia.org/wiki/Herd_immunity

https://www.mdanderson.org/cancerwise/what-is-covid-19-coronavirus-herd-immunity-when-will-we-achieve-herd-immunity.h00-159383523.html

https://www.medpagetoday.com/infectiousdisease/covid19/87812

https://www.seattletimes.com/nation-world/what-is-herd-immunity-and-why-are-trump-officials-pursuing-an-idea-who-calls-dangerous/

https://talkingpointsmemo.com/news/wh-covid-adviser-advocating-controversial-herd-immunity-approach