Last Updated on 21/12/2021 by Ulka
According to an increasing amount of early evidence, the COVID vaccines used in most parts of the world provide essentially little protection against infection with the extremely contagious omicron form.
All vaccinations appear to provide some level of protection against major omicron disease, which is the most important goal. However, only the Pfizer and Moderna vaccinations appear to have an initial success rate of halting infections when boosted with a booster, and these vaccines are not available in most parts of the world.
Early research reveals that alternative vaccines, such as those made by AstraZeneca NSE -2.36 per cent, Johnson & Johnson, and vaccines made in China and Russia, offer little to nothing to limit the spread of omicron. Because most countries’ inoculation programmes are based on these vaccines, the gap could have a significant impact on the pandemic’s outcome.
A global outbreak of illnesses in a world where billions of people are still unvaccinated not only jeopardises the health of the unvaccinated but also increases the risk of new variations emerging. The gap between countries’ abilities to weather the pandemic will almost probably widen. Furthermore, news of vaccine efficacy against omicron infection could dampen immunisation demand in the underdeveloped world, where many people are already wary or busy with other health issues. The majority of evidence so far comes from laboratory tests, which don’t represent the whole range of the immune system’s response, and not from studies of real-world populations. The outcomes, on the other hand, are stunning.
The Pfizer and Moderna vaccines use a novel mRNA technology that has consistently provided the highest protection against infection across all variants. All of the other vaccinations work by inducing an immune response using older ways. Sinopharm and Sinovac, two Chinese vaccinations that account for over half of all vaccines administered worldwide, have essentially no protection against omicron infection. These shots, which are also commonly utilised in low- and middle-income nations such as Mexico and Brazil, have been given to the vast majority of individuals in China.
The Oxford-AstraZeneca vaccine failed to prevent omicron infection six months after vaccination, according to a preliminary efficacy study conducted in the United Kingdom. This vaccine, known as Covishield, was given to 90% of immunised persons in India; it was also widely utilised across much of Sub-Saharan Africa, where COVAX, the worldwide COVID vaccine programme, provided 67 million doses to 44 nations.
According to researchers, the Russian Sputnik vaccine, which is widely used in Africa and Latin America, will provide similarly poor protection against omicron.
The Johnson & Johnson vaccine has been in high demand in Africa due to its single-shot delivery regimen, which makes it simple to administer in low-resource settings. However, it, too, has demonstrated a minimal capacity to prevent omicron infection.
Vaccine-induced antibodies are the initial line of protection. The shots, on the other hand, encourage T cell proliferation, and preliminary research suggests that these T cells still recognise the omicron variety, which is critical in preventing severe disease.
“You lose protection against asymptomatic mild infection first, but you keep protection against serious sickness and death much better,” said John Moore, a virus expert at Weill Cornell Medicine in New York. He referred to the fact that omicron looks to be less harmful than the delta form as a “silver lining.”
However, according to J. Stephen Morrison, head of the Center for International and Strategic Studies’ Global Health Policy Center, this protection will not be adequate to prevent omicron from causing global disruption.
“The sheer quantity of infection will overwhelm health services,” he said, “simply because the denominator will be so large.” “What does the world look like on the opposite side of a universal outbreak of infection, a shock?” Is it ‘The battle is over,’ or ‘The conflict has just entered a new phase,’ or something else entirely? We haven’t even begun to consider any of that.”
People who contract the virus in breakthrough instances may only have an asymptomatic infection or moderate disease, but they can transfer it to unvaccinated people, who may become more seriously ill and become a source of new variations.
More data is needed before drawing conclusions regarding vaccinations’ effectiveness against omicron, according to Dr. Seth Berkley, CEO of Gavi, the global vaccine alliance, and expedited immunisation should remain the emphasis of pandemic response.
According to preliminary evidence from South Africa, omicron has a substantially higher likelihood of reinfecting patients who have already been infected with COVID than the original virus and earlier variations. However, some public health experts feel that nations that have already seen severe COVID outbreaks, like Brazil and India, maybe immune to omicron, and that vaccination after infection results in high antibody levels.
“The combination of vaccination and viral exposure appears to be more effective than just having the vaccine,” said Ramanan Laxminarayan, a New Delhi-based public health researcher. He pointed out that while India’s adult vaccination coverage is just approximately 40%, the country has 90% exposure to the virus in some locations.
“Without a doubt, omicron will overwhelm India,” he said. “However, India should be protected to some level as a result of immunisation and exposure.”
China lacks this layer of defence to back up its ineffective vaccines. Few people have had previous exposure to the virus due to China’s vigorous efforts to stop it from spreading within its borders. In Wuhan, where the pandemic began, only about 7% of the population was affected.
AstraZeneca and Chinese and Russian vaccines have been used extensively throughout Latin America. More than 90% of Chileans had two doses of one vaccination, according to Mario Rosemblatt, an immunology expert at the University of Chile, but the vast majority of them were Coronavac, the Sinovac injection. He claims that high vaccination coverage combined with early findings that omicron does not because major sickness has given the country a false sense of security.
“We have to persuade people that it doesn’t work that way: If you have great transmissibility, the health system would be overburdened because the number of individuals who get sick will be higher,” he added.
Brazil has advised that all persons who have been vaccinated have a third dosage, and it has begun utilising Pfizer’s vaccine for all boosters, but just 40% of those who have been vaccinated have shown up for the additional shot. Dr. Amilcar Tanuri, a virus expert at the Federal University of Rio de Janeiro, expressed cautious optimism that the high levels of previous COVID exposure would mitigate omicron’s impact but noted that the most vulnerable Brazilians were given Coronavac first, and tens of millions more were given AstraZeneca. Morrison called omicron’s capacity to avoid vaccination protection “a tremendous setback” for low- and middle-income countries, where the focus is still on administering first shots rather than boosters.
“Doesn’t the world get divided into two parts?” he said. “Those who have a short path to booster’s vs those who have made very little progress and are suddenly subjected to this new standard.”
Only 13% of Africans have received at least one dose of the COVID vaccine.
According to Laxminarayan, the Indian government is considering booster shots, but the delta variety still poses a big threat in India, and two vaccine doses provide protection against delta. As a result, the government is faced with a difficult decision: focus on getting those who are still unvaccinated or only partially vaccinated to two doses, or try to get boosters to older people and those with high-risk medical problems to protect them from omicron.
The finding that non-mRNA vaccines give minimal protection against omicron infection may diminish demand for doses in areas that are already failing to meet demand, according to Morrison.
“This calls into question the value of immunizations as a whole,” he said. “If you’re so far behind and then you get sick, it’ll fuel anti-vaccine sentiment and erode trust.”
The emerging threat to countries in the global south that have relied on non-mRNA vaccines, according to Tolbert Nyenswah, a senior researcher at the Johns Hopkins Bloomberg School of Public Health, is an indictment of wealthy countries’ failure to share that technology or help build production points in low- and middle-income countries.
As a result, hazardous variations will continue to arise from places with low vaccine coverage, prolonging the pandemic, according to Nyenswah, who served as deputy minister of health in Liberia during the deadliest Ebola outbreak in the country’s history.
According to Berkley of Gavi, governments should not relax off on breakthrough vaccination efforts or presume that only mRNA vaccines are worth delivering.
“It’s possible that we’ll see a situation where governments say, ‘If rich countries don’t want these vaccines, then neither do us,'” he said. “Of course, if it turns out that these vaccines protect against serious sickness and death that would be the incorrect interpretation.”
