The path to eliminate Kovid-19 is long and paved with uncertainty. Counting continues in many countries Vaccines to create adequate immunity in their populations so that SARS-COV-2 is not able to find those susceptible to infection, which slows the transmission of coronovirus and eventually stops. But even with the rollout of highly effective vaccines, vaccination coverage may not reach that level – the so-called Herd immunity limits anytime soon. For one thing, it is It is not known what level of immunity is necessary and whether the vaccines will Powerful enough to achieve it. There is danger of Emerging coronavirus variants that may weaken immune effects.
1. Can Kovid-19 be deleted?
so far, Only one human disease – smallpox – has been officially done is erased; I.e. reduced to zero cases and kept longer without continuous intervention measures. Smallpox is a highly effective vaccine and is thanks to the fact that humans are only mammals Naturally susceptible to infection with Variola virus which sometimes causes fatal disease. Man is the only known reservoir Poliovirus, yet it still spreads In some countries, widespread use of effective immunization and despite 32-year-old causes paralysis The global eradication effort SARS-Cove-2 is considered to sustain nature in horseshoe Bats, and mink, are known to infect cats, gorillas and other animals. Wiping the virus will require it to disappear from every susceptible species, which is not possible. In countries that successfully suppress Covid-19 cases, Disease eradication has been proposed instead.
2. What is elimination?
This is when the result of efforts to suppress an outbreak Zero new cases of a disease or infection in a defined area over a continuous period. There is no official definition of how long it should be. Make a proposal Corresponding to twice as long as 28 days The outer limit of the incubation period of SARS-CoV-2 – the time between infection and the presence of symptoms. Some countries, such as New Zealand, have achieved zero new cases for long periods using border closures, lockdowns and diligent case detection and isolation. during An epidemic, which is the outbreak of a new infection across the continent, is to maintain the eradication of any infectious country Challenging, if not impossible, as the international threat from the virus threat re-enters the country.
3. Will vaccines eliminate Kovid-19?
it’s hard to say. Don’t know what To prevent the coronovirus from circulating, the population must have immunity, or even the most potent vaccines will be able to prevent it from spreading. One study speculated that preventing transmission, 55% to 82% of the population require immunity, which can be achieved through infection or through vaccination. However, herd immunity In the Brazilian state of Manaus, Amazonas was not achieved, even after an estimated 76% of the population was infected. Nevertheless, there is reason to believe that mass vaccination would have a more powerful effect as vaccines appear to have stronger and more durable protection from a pre-infection.
4. How effective will vaccines be?
There is good evidence that shots are made by Pfizer Inc.Biotech SE and Modern Ink are very effective – up to 95% – on preventing recipients from developing Kovid-19 on their own. However, data on their ability to prevent people from developing asymptomatic infections or transmitting the virus to others have not been released. The gold standard in vaccinology is to prevent infection as well as disease, so-called provides Sterilizing immunity. But this has not always been achieved. For example, the measles vaccine prevents infection so that the virus is not spread among the vaccinated people, while the vaccine for it Whooping cough works well to prevent serious illness but is less effective at preventing infection. Encouragingly, A. Modern studies of the Kovid vaccine in monkeys suggested that it would reduce, if not completely prevent, the transmission of the virus. Using diagnostic tests AstraZeneca PLC vaccines indicate that it may be less than 60% effective in preventing infection – it does not reduce the likelihood of achieving herd immunity, even if everyone in the population received two doses.
5. How are virus factor changes?
Researchers reported new, fast-spreading B.1.1.7, 501Y.V2 and P.1 variants in the UK, South Africa and Brazil to study the ability of antibodies in the blood of recovered Kovid-19 patients. Some research indicated the ability for these infections to survive the immune defenses borne by natural infections. Scientists cautioned that lab studies are only indicative and there is no evidence that this is actually happening in the community, or whether vaccine-borne antibodies would be less effective against the new strain.
6. Is infection preventable to prevent cases of Kovid-19 vaccines?
No vaccine Completion is not necessary for public health benefits. New Zealand Vaccinologist Helen Pettusis-Harris points to rotavirus and chickenpox as examples of diseases that “have almost been eliminated by using vaccines to prevent serious diseases, which is quite good at preventing any disease, but it Does not completely prevent infection at all. ” Since SARS-CoV-2 is transmitted through respiratory particles from an infected person’s throat and nose, a vaccine that reduces the amount of virus in the respiratory tract or reduces the frequency of an infected person reduces the likelihood of coughing. Can and can be transmitted to others Effective Reproduction Number (RAY), which is the average number of new infections estimated to stem from a single case. Mike Ryan, Head of At the World Health Organization’s emergency program, journalists reported on January 25 that instead of focusing on eliminating SARS-CoV-2, success was seen as “reducing the ability to kill the virus, putting people in to be seen” In the hospital, To destroy our economic and social life. “
7. What if Kovid-19 is not eliminated?
David Heyman, WHO’s strategic and technical advisory group chair for infectious threats, Warned in late 2020, “It seems the destiny of SARS-CoV-2 has become endemic.” Viruses that are spatially continuously spreading often cause periodic spikes in the community, when disease symptoms and human behavior patterns promote transmission. Examples include norovirus, the infamous cause of gastroenteritis on cruise ships, and a myriad of viruses including four Coronavirus, which causes the common cold, especially in winter.
8. What are the implications?
It is unknown how things will evolve, but researchers have begun to spin the scenarios. Those who survived Kovid-19 and those who have been vaccinated against it will likely be protected. Against the disease for some time. It is likely Reactivation of virus or booster shot of vaccine Ensure their safety. In this way more and more people develop immunity, the virus will find those who are not yet immune, so until herd immunity is established to protect them. This would mean people who cannot get vaccinated – because their immune system is compromised, or they are allergic to vaccine ingredients, or they are too young (any of the authorized vaccines in Western countries are for children. Not approved) – will remain weak. Some scientists have predicted that, once the endemic stage is reached and the primary risk of the virus is in childhood, SARS-CoV-2 may occur There is nothing more viral than the common cold.
- Devi Sridhar and Deepti Gurdasani of Edinburgh University gave detailed information Hard lessons learned from a largely uncontrolled Kovid-19 epidemic in Manaus, Brazil.
- Anita Heywood and Raina McIntire of the University of New South Wales What is eradication, eradication and suppression, and eradication of Kovid-19 Look like MacIntyre also presents Principles of vaccine programs for Kovid-19 control.
- Related quicktech how Vaccine hesitancy threatens to delay epidemic end, why Delaying second shot of Kovid-19 vaccine is messy, why The mutated variant is very worrisome, how is the coronovirus Sent, Vaccine rollout, whether you can Forced to vaccinate, coronavirus Treatment and Unanswered questions about the virus.
– With the help of Alisa Odenheimer