With the level of infection of the Delta transformation, more and more experts believe that countries are difficult to achieve community immunity, at least in the short term.

According to most epidemiologists, community immunity is the necessary immunity level in a country so that the virus can no longer spread widely.

In theory, community immunity will be achieved if the R0 coefficient falls below 1, ie an average of an infection will spread under someone else.

However, NCOV is infecting easier with the appearance of new strains.

Allen Cheng, former Victorian Health Director in Australia, estimates the R0 coefficient of the Delta strain is about 5, while the US Disease Control and Prevention Center (CDC) offers 5-9, nearly equal

In addition, vaccines are not 100% effective before NCOV.

Professor Peter Doherty, the Nobel Prize winner in 1996, explains that this is because the vaccine is injected into the hand, but to prevent NCOV infection, antibodies should be maintained in the nose.

The vaccine antibody will help prevent the virus from spreading systems in the body, but it is difficult to keep antibodies in the nose, Professor Doherty said.

An elderly who was vaccinated with Covid-19 in Netanya, Israel, on January 19.

Professor Fiona Russell, a leading specialist in the Melbourne University of Australia, said these things could make the perspective to reach community immunity.

Professor Andrew Pollard, head of Vaccine Oxford Vaccine Cooperation CoView-19 with Astrazeneca, on August 10 also pointed to the UK MPs that with the Delta transformation, the community immune target was no longer available

The problem is that NCOV is not measles.

Meanwhile, Professor Robert Booy, a senior specialist at the Australian National Immunization and Monitoring Center, indicating that the problem is not in community immunizations.

Community immunity is an ideal state to aim, but only need to close this goal, we still achieve what I want to be a disease control, meaning that all outbreaks occur in time

Sydney Mingnix's Liam Mannix science commenter said that in the absolutely unable to remove Covid-19 by community immunity, the world will witness the three scenarios of the pandemic, which is NCOV will only inductive

The first scenario is said to be the most optimistic, based on the fact that at least 4 corona viruses only cause common colds and are not worrisome.

Many people hope personal immunity to Covid-19 will gradually become strong, partly thanks to the vaccine and the injections remind regularly.

When people are exposed to regular viruses, the protective capacity of the immune system will be increasing in future exposure, even in the face of the transformation, Jennie Lavine, the studyer of infectious diseases

The second scenario is Covid-19 to become a seasonal disease.

At that time, instead of becoming a common cold as the first scenario, Covid-19 will be similar to the flu, which is boosting seasonally and a number of years of more dangerous transformations.

The darkest scenario is that the new NCOV strains constantly appear, causing the protective shield of the vaccine.

Without any scripting Mannix mentioned that Covid-19 will disappear.

After spacious vaccination, reducing the case of suffering and death, we need to think and respond to Covid-19 in the same way that other viruses appear annually, she comments.