Underlying Conditions that Can Influence Breakthrough COVID-19 Cases in Vaccinated Individuals.
The constantly repeated mantras of the COVID-19 vaccine makers have been that the risk of infection after vaccination is extremely low. The COVID-19 vaccines from Pfizer, Moderna and Johnson & Johnson were not intended to completely end transmission of the virus, rather they were supposed to reduce transmission to acceptable rates—i.e., sufficiently low enough that the virus would die out in a vaccinated population—and reduce the severity of infection.
A new study published in the United Kingdom found that the vaccines are, by and large, working as intended. Of the 1.2 million people in the U.K. who were vaccinated, less than 0.5 percent suffered a breakthrough infection following one dose, and less than 0.2 percent had a breakthrough infection after both doses of the vaccine. More importantly, the chances that the breakthrough infection would be asymptomatic was 63 percent after the initial dose but 94 percent after both doses.
How Preexisting Conditions Affect Breakthrough Infections
Since the start of the pandemic, it has been widely recognized that health conditions like heart, lung or kidney disease can raise the risk of infection, hospitalization, and death. It appears that these preexisting health conditions can also affect the likelihood of a breakthrough COVID-19 infection.
Because the population with the greatest number of chronic health conditions or weakened immune systems is the elderly, it is seniors that have seen the most breakthrough COVID-19 infections. For example, almost ten percent of breakthrough COVID-19 infections in the state of Oregon have occurred among people living in nursing homes, and most of the deaths have been among seniors. In Minnesota, the median age for breakthrough COVID-19 hospitalizations is 74.
It is obvious that vaccination confers powerful protections against COVID-19, but these protections are insufficient for many with underlying health conditions. Although the Centers for Disease Control and Prevention has stopped tracking all breakthrough COVID-19 infections since May 2021, many states continue to do so. Among 27 states, there have been 65,000 cases of breakthrough COVID-19 infection. The CDC does, however, monitor the number of serious hospitalizations following vaccinations and this has reached 5,500 with 75 percent of these cases involving someone over the age of 65.
These may seem like significant numbers but considering that there are more than 160 million fully vaccinated people in the United States, these are statistical outliers. This is underscored by the fact that many of these breakthrough COVID-19 infections may be asymptomatic but were detected during the treatment of an unrelated health issue.
The Risk of New COVID-19 Strains
There has been a lot of media coverage of new COVID-19 variants like Delta and Mu, which, in turn, has raised concern among the public. While it should be noted that almost all the hospitalizations in recent months are among the unvaccinated, the primary culprit has been the Delta variant of COVID-19.
A study from Israel found that 96 percent of vaccinated people who were hospitalized with COVID-19 also had an underlying medical condition like heart disease, diabetes or hypertension. Those most vulnerable to a breakthrough infection are seniors with a chronic health issue or have a compromised immune system.
Another report out of Singapore, however, found that vaccines do provide quite a bit of immunity against the delta strain of COVID-19 even for older people. Out of a population of 218 vaccinated and unvaccinated patients admitted to a hospital, the 84 vaccinated patients were three times more likely to be asymptomatic than those not vaccinated. Even those vaccinated patients with COVID-19 symptoms were more likely to have fewer symptoms, less systemic inflammation, and better clinical outcomes.
One outbreak in Massachusetts highlights the power of vaccination against the Delta variant. Of the more than 900 people infected—primarily by the Delta strain—almost 74 percent were fully vaccinated. In the course of this outbreak, there were no deaths and only 7 hospitalizations. At least one hospitalized patient was unvaccinated, and two of the hospitalized that were vaccinated had underlying health conditions.
Although current vaccines seem to offer sufficient protections against most of the versions of COVID-19 that we know about, there is some concern that emerging variants could breach their immunities. Among the more worrisome variants is the Mu strain that was first identified in Columbia in early 2021. Ongoing research cannot confirm that the Mu variant is vaccine-resistant, but there is some evidence that it is different enough from the original strain that it may, at least, be able to evade some of the antibodies that are produced as a result of our current vaccines.
Even if Mu is not the vaccine-resistant strain that the healthcare community dreads, there is growing concern that there soon could be one that is. Mu is the fifth major variant to appear in the past two years, and new variants are almost certain to appear. Without a global population that is sufficiently herd immunized—which according to health experts could be from 75 to 90 percent of the population–COVID-19 will continue to multiply and mutate.
Should You Be Worried about Breakthrough Infections?
From the available data, breakthrough COVID-19 infections do not appear to be any serious threat to vaccinated persons. It is less likely that an infection might occur, and even if you were to catch COVID-19, you would most likely have mild or no symptoms.
At this point, the only vaccinated people that should be seriously concerned about breakthrough COVID-19 infections are those with chronic medical conditions like hypertension or diabetes, or those with compromised immune systems like the elderly or people on immunosuppressant drugs. Luckily, the federal government is aware of the risk to these populations and has authorized booster shots for them.
If you fall into one of these vulnerable categories, then you should get a booster shot as soon as possible. You should also continue to practice good hygiene like staying six feet from strangers, wearing a mask in public, and frequently washing your hands with soap.
Article written by: Dr. Robert Moghim – CEO/Founder Colorado Pain Care
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