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Herd immunity for COVID-19 variants


As we explored in our recent blog post, "COVID-19 and the Missing Patient," the COVID-19 pandemic has had far-reaching consequences on the overall health of our country. Until we reach herd immunity, we run the risk of losing more lives to COVID-19 and simultaneously creating new health issues by delaying care.

The longer the virus continues to circulate and pose a threat, the longer it will take people to feel comfortable returning to the doctor's office.

Herd immunity

A key milestone we need to return to a new normal is “herd immunity.”

As you likely know, "herd immunity" is when the majority of a population has immunity to a disease thus making it harder for the disease to spread. There are two primary ways people gain immunity to disease – either through vaccination or through exposure to – and recovery from – the virus.

According to the CDC, COVID-19 herd immunity will be achieved when between 70% to 90% of the population has immunity to the virus.

The COVID-19 vaccination race

While we haven’t yet achieved herd immunity for COVID-19, the U.S. has dramatically picked up the pace for vaccinations.

According to data from the CDC, nearly 44% of the population has received one shot of the COVID-19 vaccine and nearly 31% of the population is fully vaccinated. And as of April 19th, all adults 16+ are eligible for vaccinations, which should significantly increase the number of people who gain vaccine immunity.

However, COVID-19 variants could threaten these hard-earned gains.

How COVID-19 variants will impact herd immunity

Right now, experts are concerned with the spread of the B 1.1.7 variant, otherwise known as the British variant, since data indicates it may be more contagious. According to the CDC, B.1.17 is now the dominant strain of COVID-19 in the U.S.

According to Definitive Healthcare’s COVID-19 Reopening Predictor, in states such as Michigan, where B.1.17 is the dominant strain, there has been an increase in cases and hospitalizations.

In fact, our data shows Michigan’s reproductive rate is trending upward. The reproductive rate is a key metric that gauges how many new individuals will likely be infected by one COVID-positive person. With Michigan’s number rising, it indicates community spread of the virus is increasing and more people are at risk of being infected.

Additionally, according to Definitive Healthcare’s COVID-19 Capacity Predictor, Michigan’s hospitalizations, ICU capacity, and ventilator usage have spiked in recent days to rates last seen during the second wave in December 2020. Healthcare resources in the state are under added strain as they seek to combat an increase in COVID-19 patients.

If additional variants emerge, which becomes more likely the longer the virus circulates in a population, vaccines may become less effective. Booster shots would be necessary to keep those vaccinated safe from emerging variants if they threaten vaccine immunity. Variants could threaten the timeline out for safe reopenings.

Herd immunity and care delays

With more contagious variants circulating, cases on the rise, and restrictions being lifted, we run the risk of never achieving vaccination immunity.

Until herd immunity is achieved, we’ll continue to lose people to COVID-19, as well as to other illnesses such as heart disease, cancer and diabetes as people continue to delay routine screenings.

According to data from the Definitive Healthcare Medical Claims Database, Americans missed more than 2.5 million new screenings in 2020 for heart disease, cancer, and diabetes. Patients are coming in with more severe complications and additional comorbidities for these diseases, adding even more cost to the healthcare system and lowering the quality of life of millions of Americans.

What we can do to achieve herd immunity

There is a light at the end of this tunnel. To mitigate the impact of COVID-19 on the entire population and get patients back into the doctor's office, we can do three things:

  1. Continue to follow local masking and social distancing guidelines. This is particularly important if you are not vaccinated to reduce community spread.
  2. Get vaccinated as soon as you can. Vaccines are safe and effective. You can use VaccineFinder to find locations and schedule an appointment for vaccination.
  3. If you're vaccinated, schedule an appointment with your primary care provider to check in on screenings you may have missed over the last year.

Want to understand when it may be safe to reopen and enter the new normal? Check out our COVID-19 Reopening Analysis Predictor.

To learn more about COVID-19 vaccination trends, check out the replay of our FiercePharma webinar "Spotlighting COVID-19 Vaccination and Delayed Care Trends."

Definitive Healthcare

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Definitive Healthcare

This blog was written by a former contributor at Definitive Healthcare. At Definitive Healthcare, our passion is to transform data, analytics and expertise into healthcare…

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