Understanding many aspects of the COVID-19 pandemic is constantly changing. One of them is the amount and duration of immunization and immunity to natural disease.
We now have more information and experience on viruses and vaccinations. For example, we once thought – perhaps mistakenly – that vaccination provides a broader and stronger immunity than the one acquired after infection. Also, new variants have emerged, especially those that have changed the ohmicron equations.
Of course, SARS-CoV-2 is a cruel, disgusting, inventive, and resistant virus that is able to avoid immune protection from both infection and vaccination; so it is very difficult to control. Think about it.
Here is my assessment of what is known about the amount and duration of immunity acquired. Our understanding will continue to develop.
The best evidence from the first two studies of the mRNA vaccine is that post-infection immunity is approximately equal to or higher than that of immunization. Some natural disease studies believe that protection against re-infection lasts about six months and possibly more than a year. Reinfections are usually less severe than primary infections.
The pre-omicron vaccine was given against the infection, but very high (approximately 95 percent) after four to six months it dropped to a low level of protection, but at a high level to protect against severe immunity and death. Immunosuppression (third dose) restored immunity to infection, but was similarly short-lived.
Hybrid immunity – any combination of vaccines – plus natural, disease-induced immunity provides the greatest overall protection. These studies do not include amplifiers. In addition, two studies published this spring in the New England Journal of Medicine provide significant additional and long-lasting protection for people who have previously been infected.
Omicron deserves special attention. It has a special ability to escape and spread our immunity after infection. As a result, the level of reinfection increases sharply. Of the reported cases, recurrent infections accounted for 1 percent of infections; now 10 percent. The effectiveness of previous infection protection against infection decreased from 90 percent in previous variants to 56 percent in omicron.
There has also been a significant increase in post-vaccination infections and the percentage of hospitalizations and deaths of the vaccinated elderly population.
Preliminary data also show that for omicrons, amplifiers (third and fourth doses) have improved infection but provide relatively less protection, but remain very effective in preventing severe infections and death. Busters are especially important for the elderly and people with weakened immune systems.
The pandemic is not over yet. We need to do the same. But with about 50 percent of Americans infected and two-thirds vaccinated, they will soon have enough “collective” immunity to transition from the epidemic to the endemic phase of COVID-19. Then, we hope for a predictable, manageable, and less severe disease experience with a seasonal appearance similar to the flu that requires only vaccination each year.
But what kind of vaccination is this? What options does it include? Is it possible to create a more effective universal COVID vaccine against all current and future strains?
Numerous studies have shown that people who have not been vaccinated against infection, hospitalization, and death are more immune to disease and vaccination than those who have not been previously infected.
However, this vaccine, unlike natural disease, reduces morbidity and mortality and moves us to an endemic phase.
Dr. Richard Feldman is a family physician in Indianapolis and a former Indiana health commissioner. Send it to email@example.com.
This article first appeared on the Evansville Courier & Press website: Data on the growth of natural and vaccine-based COVID immunity