What is Herd immunity? Herd immunity in COVID19/ Corona virus

What is Herd immunity?

When most of the population is immune to an infectious disease, this provides indirect protection to the remaining population who are not immune to that particular infection is called herd immunity or herd protection.
If around 70-80% of the total population gets immunity from a specific disease or infection i.e 4 out of 5 people won’t be sick by that infection. Then it’s called herd immunity.
How can Herd immunity be useful during Coronavirus in India?
 We use to have diseases which were common like measles, polio, chickenpox in past but now these diseases are very rare because either we had developed a vaccine to have a herd immunity or once the person got infected from any of this disease got herd immunity and because of this herd immunity these diseases became rare.
So there are 2 ways by which we can have herd immunity from this Coronavirus and can save people from this virus. The 2 ways are :
1. To take the vaccine against this coronavirus which can protect us from this virus.
2. To get the maximum population infected from this virus to develop herd immunity. Will be needing around 70% of the total population to get infected to develop herd immunity.
But the problem is, firstly there is no vaccine available against coronavirus in the whole world and second because of high rates of death during the infection from coronavirus mainly in elder age and in children due to weaker immunity, it’s risky to risk life’s of many people to get infect and develop herd immunity.
Our aim should be :
1. Decrease the number of deaths.
2. Control virus transmission.
3. Reduce the morbidity(infection) and mortality(deaths) by early intervention.
What all options we have to protect India from coronavirus?
1. Let’s assume we don’t take the precautions for the spread of virus and don’t maintain the lockdown & social distancing.Virus will infect many people in few months like what is happening in USA and other European countries and because of our large population and poor medical facilities, our hospitals, doctors,nursing staff will be overloaded which will lead to a medical emergency and high mortality i.e many deaths as comparitive to those developed countries
2. Second way is that we take all the preventive measures to stop the spread of this virus by lockdown, social distancing, personal hygiene etc and reduce the rate of infection untill the vaccine gets available. This will need a lot of effort from everyone of us as we don’t know till when the vaccine will be available in markets and till then we need to maintain the lockdown and social distancing. This will cause a lot of financial problems, whole world’s economy will be affected and a lot of financial pressure will come to every one of us.
* 3. The best way can be somewhat in between both. We can allow the younger population to move around freely (but no gathering of more than 5 people) as we have seen that younger age people have less percentage of severity and deaths due to coronavirus as compared to elder population and children. We also don’t want younger population to get effected together as that will put a burden on our medical care system which will lead to more deaths.
-Isolate people with co-morbid condition and elder population( even at home from younger age population).
– Isolate corona positive patients untill there last 2 reports come negative.
By this we can relax the social distancing measures when number of infection cases fall and then to implement the restriction again when the cases increase. This way we can also help our people to have herd immunity slowly and by protecting elder age, children in isolation one can decrease the mortality rates. i.e can decrease deaths through this virus.
I know this 3rd step of getting around 70% of populations infected from this virus is a risky way of getting the herd immunity as death rates are very high in elder age, children due to weak immunity in coronavirus as compared to other diseases or infection in past. But presently this is the best way we can have herd immunity till the vaccines come.
So it’s always to have a gap between infection over time so that there will be no burden on our healthcare system which leads to less death.
We also hope sooner the vaccine is developed so that large population can get immunity against this virus. Till then everyone should follow this lockdown and social distancing to protect ourself and our country.
Dr. Abhishek singla