Facts about coronavirus vaccine

It is hard to know without knowing how effective the vaccine is going to be in case of corona Virus that has infected 54 million and has taken life of 1.3 million people. It is thought that 60-70% of the global population need to be immune to the virus in order to stop it spreading easily (known as herd immunity) – in other words, billions of people, even if the vaccine works perfectly.

But if you want your life to get back to normal, then we need a vaccine. Even now, the vast majority of people are still vulnerable to a coronavirus infection. It is only the restrictions on our lives that are preventing more people from dying. But vaccines safely teach our bodies to fight the infection. This can either stop us catching coronavirus in the first place or at least make Covid less deadly. The vaccine, alongside better treatments, is “the” exit strategy.

Not everyone responds the same to immunization. People will be watching the results in older people closely, because they are most at risk from the virus. But history also suggests any vaccine could be less successful in old people because an aged immune system does not respond as well to immunization. We see this every year with the annual flu jab. It may be possible to overcome this by either giving multiple doses or giving it alongside a chemical (called an adjuvant) that gives the immune system a boost.

In UK Pfizer are the first to share data from the final stages of testing – known as a phase 3 trial.

This is a crucial point in vaccine development, where some experimental vaccines will fail. The vaccine uses a completely experimental approach, which involves injecting part of the virus’s genetic code into people, in order to train the immune system. About 43,000 people have been given the vaccine, and no safety concerns have been raised.

Pfizer believes it will be able to supply 50 million doses by the end of this year, and around 1.3 billion by the end of 2021.The UK should get 10 million doses by the end of 2020, with a further 30 million doses already ordered.

However with tropical heat, remote island communities, a dearth of ultra-cold freezers and a limited quantity available, many Asian countries and developing nations aren’t betting on Pfizer vaccine solving their Covid-19 crisis any time soon.

The World Health Organization (WHO) estimates about 70pc of people must be inoculated to end the pandemic, and Asia alone is home to more than 4.6 billion — or three-fifths of the global population.Pfizer can manufacture only a limited quantity of the vaccine next year — about 1.3 billion doses, according to a report by NPR. But more than 80pc of the supply is already spoken for by the United States, the United Kingdom, the European Union, Canada and Japan.

This means that there is hardly anything left for the rest of the world, particularly poorer countries. For most people in low- and middle-income countries, this vaccine is not likely to be available, at least, by the end of next year,

Japan is among three countries in Asia Pacific that have announced supply deals for the Pfizer/BioNTech vaccine. It has signed a deal for 120 million doses, while Australia has secured 10 million doses and China’s Fosun has secured 10 million doses for Hong Kong and Macau.

Professor AttaurRahman, head of the Task Force on Science and Technology, told Voice of America that it would be premature for Pakistan and other developing nations to celebrate Pfizer’s announcement.

“The cold storage infrastructure and chains to take this from the airport, across cities and countries are missing in the developing world,” he told the publication. He added that patients would require two doses of the vaccine three weeks apart and a “low temperature carriage” makes it all the more difficult to carry out inoculation.

There are 10 more vaccines in the final stage of testing,

The leading contenders are:

• The University of Oxford and AstraZeneca vaccine in the UK
• Moderna in the US
• CanSino with the Beijing Institute of Biotechnology in China
• Gamaleya Research Institute in Russia
• Janssen
• Beijing Institute of Biological Products and Sinopharm in China
• Sinovac and InstitutoButantan in Brazil
• Wuhan Institute of Biological Products and Sinopharm in China
• Novavax in the US

It is worth noting that four coronaviruses already circulate in human beings. They cause common cold symptoms and we don’t have vaccines for any of them.The point of a vaccine is to harmlessly show parts of the virus to the immune system so it recognizes it as an invader and learns how to fight it.

However, there are many ways to do this and researchers are using different approaches.Both the Pfizer and Moderna vaccines inject pieces of the coronavirus’s genetic code. Once inside the body, this starts making viral proteins to train the body. This is a completely new technique.

The Oxford and Russian vaccines take a harmless virus that infects chimpanzees, and genetically modify it to resemble coronavirus, in the hope of getting a response.

Two of the big China-made vaccines use the original virus but in a disabled form, so it cannot cause an infection.

Understanding which method produces the best results will be vital. Challenge trials, in which people are deliberately infected, could help answer these questions.

• A way of producing the vaccine on a huge scale must be developed for the billions of potential doses
• Regulators must approve the vaccine before it can be given
• Finally, there will be the huge logistical challenge of actually immunizing most of the world’s population