Herd Immunity and Covid-19: What is "herd immunity" and will we acheive it with Covid
During the COVID-19 pandemic there have been some that have tossed around the term “herd immunity” without really understanding what it is. In reality, herd immunity as it relates to disease states simply means that a large enough percentage of the population has achieved the antibodies to that disease so that it can no longer spread. Achieving the number of people that is large enough to stop the spread of the disease is called the “threshold.” There are two ways to achieve herd immunity: through widespread vaccinations or by the population getting the disease. When it comes to pandemics, the latter is not the best choice. Waiting for a pandemic to circulate through a population can take years while people are sick and dying.
Herd Immunity of Past Pandemics
The Black Death is one of the most infamous of pandemics. From 1346-1353 the plague spread throughout Europe. Contagions occurred so quickly that people had little time to recognize that their friends and family had the disease before they were dead. Citizens in many countries could do little but carry that massive quantities of bodies to large pits for burial. By the time the Black Death was finished it had killed 60% of the population of Europe or over 50 million people.
The Spanish Flu is occurred in the years of 1918-1919 and was part of the H1N1 virus. The mortality rate was highest in a variety of age groups: Under 5 yrs., 20-40 yrs., and over 65 years. Just as with the Black Death, there were no antibiotics or vaccines, and the world was also in the middle of World War I. The war meant that more people were traveling to a variety of countries, spreading the virus faster than any that had previously infected human beings. The only methods of treatment that were known involved non-pharmaceutical interventions such as quarantining, isolation, limiting gatherings, wearing masks, and good hygiene. However, none of these were enough because not all people complied with the restrictions. By the time the Spanish Flu ended, one-third of the population of the world or 500 million people had died.
Herd immunity of COVID-19 through natural processes, even with antibiotics, will result in millions of death around the globe. Given the political climate of the topic of COVID-19, it has already been seen that as long as people don’t believe in its existence or refuse to quarantine, wear masks, or social distance, even today’s society has behavior that would continue to spread the virus.
In addition to the large percentage of deaths in the population, research involving COVID-19 is finding that around 50% of thepeople that have had the virus and survived are also showing long term/life long problems involving major organs, specifically heart problems.
Herd Immunity Through Vaccines
In comparing the two methods of gaining immunity it becomes obvious that allowing the deaths of large percentages of the population to achieve the antibodies to fight off a virus isn’t a good choice. Natural methods required the deaths of millions of people in order to meet a herd immunity “threshold.” Today’s science has allowed us to make medical achievements of vaccinations that can save lives. The pharmaceutical companies now have the ability to create vaccines that can give the body the opportunity to create antibodies without illness or death. Vaccines have been successful for many of the diseases that are contagious such as polio, rubella, smallpox, diphtheria and others.
The original vaccines used a dormant version of the virus and introduced it into the body in the form of an injection. The body’s reaction to the dormant version was to recognize it as a foreign attacker and allow the immune system to kick in and develop antibodies to fight off that particular virus. The more people that received the vaccine, the higher the number in hitting the goal of vaccine-related herd immunity threshold. Pharmaceutical companies have advanced in the methods of creating vaccines so that each one has a different way to target the specific virus. The newer vaccine designs allow for faster production to get a higher volume of the vaccine out to the public.
There are some individuals that object to vaccines based on reasons that run the gamut from religious, skepticism, and fear. If the percent of these people is large enough they can tip the scales for herd immunity threshold, allowing the disease to continue to spread. An example of this has been in the recent resurgence of measles in some parts of the world, including the U.S. where the vaccination rates for measles were reduced.
Viruses have survived through the millennia due to their ability to evolve and change. When the number of hosts for infection becomes too low, they alter themselves into a variant. We are seeing this happen with COVID-19 as new variants are appearing in a few countries and areas. Thus far, the current vaccines that have been developed have been able to combat the variants, but this might not always be the case. To address the possibility of newer and stronger COVID-19 variants pharmaceutical companies are already researching and developing the vaccine “boosters” that may be required to supersede the variants.
Some form of COVID-19 will be around for a long time and based on history, the only safe way to achieve herd immunity for the world’s population is to address it with vaccines.