The COVID-19 vaccine and herd immunity
Globally COVID-19 vaccines have begun being rolled out. The thought process is that these vaccines will help us reach something called herd immunity — a common ending to viral outbreaks. The term has been used a lot as of late but what is herd immunity, how does it work, and how long it might take us to achieve it.
What is herd immunity?
When the majority of the population is immune to a disease this is often referred to as herd immunity. It is a type of indirect protection from a contagious disease and the more people that are immune to it the more challenging it becomes to spread it. Eventually, with no new hosts the disease dies out.
While the majority of the population can be vaccinated, there is still a portion that, for health reasons, can’t be vaccinated. This is where herd immunity protects those people. Once enough healthy people get vaccinated the rate of transmission and infection decreases significantly.
How Many People Need To Be Vaccinated Before We Reach Heard Immunity?
Every infectious disease has a different number of people that need to be infected for a disease to spread at high rates. This is known as a threshold. For a country to have herd immunity, the number of immune people has to be equal to or above the threshold.
Since every disease has a different threshold sometimes it takes time to learn what that threshold is. Measles, another infectious illness, took 95% of the population to be vaccinated before they were able to stop the spread. Polio on the other hand requires only 80% of a community to be vaccinated to snuff out new infections. Scientists still do not know what that threshold is for COVID-19.
How does herd immunity happen?
Herd immunity is achieved in two different ways. Either by large numbers of a population catching the disease and recovering from it or through mass vaccination programs.
Catching the disease
Anytime a foreign substance like a virus or bacteria enters your body, your immune system creates antibodies, which proteins that your immune system uses to identify, attack, and destroy the disease. The more exposure you have to the unwanted germ, the better your body gets at identifying and eradicating it. Eventually, you become immune to the foreign substance, as your body can attack and destroy the intruder so quickly that you don’t develop any symptoms.
People who have caught COVID-19 and recovered now have COVID-19 antibodies in their systems. The number of antibodies a person develops can vary, and scientists still are not sure how many antibodies your body will produce nor do they know how long they offer protection. Those that caught COVID-19 and developed symptoms might have more antibodies in their system than those that were asymptomatic. We do not even know if everyone that catches COVID-19 will produce enough antibodies to ward off a second infection.
Vaccination
Vaccines contain a small part of a virus, bacteria, or disease-causing organism that can be either dead or seriously weakened. A small amount of the foreign substance is introduced to your system in a controlled way, but not enough to infect you. In return, your immune system is learning how to identify the substance and how to develop antibodies. The hope is that if you’re exposed to COVID-19 in the future, your immune system will know how to destroy it before it makes you sick and contagious.
The theory is that once enough people get the COVID-19 vaccine, the number of new cases will begin to decline to the point that becoming infected is unlikely.
How long will it take for us to develop COVID-19 herd immunity?
When it comes to how quickly we can reach herd immunity, we need to consider vaccine availability, current infection rates, how to vaccinate enough people, and if the foreign substance mutates.
Vaccine availability and rollout.
While makers work around the clock to develop and produce vaccines every country is still dealing with shortfalls. Either way, we will need a significant amount of the world population to be vaccinated before we can reach herd immunity. You can track daily progress here
Keeping new infection rates low
If infection rates continue to rise, it will take us longer to reach an adequate threshold for her immunity to take over. The fewer new cases of COVID-19 there is week to week, the quicker we can reach that threshold.
New strains
It is not surprising to see that there are several new strains of COVID-19 have been detected around the world. After all, viruses normally mutate, and there should be no need to be alarmed. As more people become immune to the virus, the less chance there is for the virus has to mutate.
The best way to help your community achieve herd immunity is by following all the necessary public health guidelines in your area. Make social distancing, mask-wearing, and hand-washing part of your daily routine wherever possible. The fewer new cases there are while the vaccine is rolling out, the faster we’ll get to enjoy the benefits of herd immunity.
It is safe to say COVID-19 has been tough on all of us, not just physically but mentally as well. Make sure you speak to a doctor or therapist to get help for your individual needs.
