Corona virus: What is 'hard immunity', how much does it cost?

In order to cope with the coronavirus situation in Bangladesh, measures like shutdown or 'lockdown' were taken. The measures did not prevent the spread of the coronavirus in the form of an epidemic. Later, those arrangements were gradually relaxed. Now there are virtually no restrictions in place in Bangladesh to prevent epidemics except to close educational institutions and instruct people to follow hygiene rules after face masks.

Professor Nazrul Islam, one of the country's top virologists, said in May that there was no way out except to wait for "hard immunity" to appear in the pattern or graph of the infection. Professor Islam thinks that it is not possible to impose a strict lockdown in Bangladesh.

But four months later, restrictions have been lifted in all sectors except education. The number of identities in Bangladesh has crossed three lakhs and reached the threshold of three and a half lakhs. The death toll has also risen to 5,000. But no one in the country has been able to provide any information on whether the country has had or is going to have hard immunity.

When the coronavirus epidemic began around the world, there was talk of hard immunity in many countries. Although in the end no country has walked that path but the path of lockdown.

This is because before the invention of the vaccine, the number of people who would naturally be infected to develop hard immunity, and the number of people who would die, would be huge.

'Sheep'
Former director of the Department of Disease Control. Bay-Nazir Ahmed said the English word hard comes from a flock of sheep. And immunity is immunity.

Sheep were vaccinated to prevent infection, he said. If 80 out of 100 sheep had been vaccinated, the infection would not have spread to those flocks. Although not every one in a hundred was vaccinated, a kind of protection zone worked for them. This is hard immunity.

In the case of humans, when vaccines or vaccines are given in a certain proportion within a certain population, that community is no longer infected. This is called hard immunity.

The Oxford University Vaccine Knowledge Project website has detailed information on what hard immunity is and who it protects. It says that when most people in an area are vaccinated against an infectious disease, there is no risk of the disease spreading in that area. Because there are no more infected people in that area.

For example, if measles occurs in someone in a community, and most people are vaccinated, the disease cannot spread to anyone else. This is hard immunity or community immunity. Because of this, newborns, the elderly, and sick people who cannot be vaccinated remain immune.

The way hard immunity works

Hard immunity will only work when most people in a group are given antidotes. For example, in the case of measles, if only 19 out of 20 people can be vaccinated, then hard immunity will develop in certain communities.

In this regard, Mr. Ahmed said the number of hard immunity for various diseases has been fixed. This means that the number of people in a community who need to be vaccinated for a disease is determined by the number of people who will not be infected. For example, the number of people who need to be vaccinated to develop a strong immunity to a disease like polio is determined.

However, if immunity is not given, hard immunity does not work there. Also, if most members of a community are not vaccinated, it will not work. On the contrary, the disease will spread very soon. This is what happened in Wales in 2013. There was an outbreak of measles.

Hard immunity to coronavirus:

No coronavirus has yet been marketed. Although several vaccines discovered in different countries are now in the trial stage at different stages. Russia has already given final approval to a vaccine, although it will take more time for it to hit the market. So how will hard immunity work to deal with it?

In this case, it is said that those who are once infected with the virus, the immune system against the virus is strong.

In this way, when more people become infected with the virus, a large number of people develop immunity to the virus. This creates a protective zone within a particular community and stops the spread of the disease.

Mr. Ahmed says hard immunity works in the case of coronaviruses. Because, he thinks, more than 90 percent of people need to be infected with the virus if they are to develop strong immunity against the coronavirus.

Earlier, countries like the United States and Sweden had considered taking measures on hard immunity. From the beginning, Sweden did not seem to adhere to such a social distance.

This is not yet a recognized method of preventing coronavirus. But many think it could be a way.

According to the World Health Organization, a person infected with coronavirus can infect two and a half people.

To have hard immunity to coronavirus, at least 90 percent of people must be infected. In other words, 9 out of 10 people should be infected.

If there is to be hard immunity in the case of Bangladesh, if there are 160 million people here, then about 160 million people will have to be infected with coronavirus.

If 160 million people are infected and 0.001 percent of them have to be hospitalized, then it is impossible to provide the huge number of people who need to be hospitalized in the reality of the current health system in Bangladesh.

And because of this the number of deaths will increase at a deadly rate.

As of September 14, the number of people identified in Bangladesh is 3 lakh 36 thousand 520 people. Although the actual number of victims is much higher, there is a strong perception among many. But somehow it is not 16 crore, no doubt.

Dr. Ahmed said he is totally against the hard immunity theory in Bangladesh. Because Bangladesh does not have the system to provide health care to a large number of infected people.

He thinks that the current situation in Bangladesh would not have happened if preventive measures had been taken. This would not have been the case if quarantine had been carried out well, flights had been grounded or affected people from outside the country could not come to Bangladesh.

Decisions such as opening garments and easing lockdowns or lifting restrictions on public transport are tantamount to "neglecting preventive measures," he said. Ahmed.

"We have to pay the price," he said.