December 25, 2021

Omicron Variant: Double vaccination not enough, you need booster


By Sola Ogundipe

Have you been double jabbed with the Covid-19 vaccine? If you have, good for you, but you need a booster shot for greater protection against the Omicron variant. Double jabbing is crucial but the emergence of Omicron has made booster shots even more important.

It is now well known that Covid vaccines are less effective against the omicron variant compared with the globally dominant delta strain and other variants. Studies also show that three vaccine doses — the two preliminary shots plus a booster — significantly increase protection against omicron.

Even before the arrival of omicron, it was becoming clear that boosters were needed as vaccine protection declining after 90 days. With the omicron variant spreading rapidly, there is risk to the most vulnerable groups. Omicron also appears to be less dangerous when people are boosted with a third vaccine dose. 

It’s been  a month since the new, heavily mutated Covid strain was detected and designated a “variant of concern” by the World Health Organization. It’s now spreading rapidly. Governments around the world are desperately trying to deploy Covid booster shots to millions of people in order to bolster their protection against the more transmissible variant.

Everyone in Nigeria that is over 18 is eligible for a booster. You just need to have had your second dose six months ago or more. A booster dose is different from the third doses being offered to people with weakened immune systems, who may not have responded fully to their first two doses. 

Preliminary studies have found that omicron reduces the efficacy of two-dose Covid vaccines, but a booster shot can restore a significant level of protection. 

READ ALSO: COVID-19: Omicron not as deadly as previous variants ― Medical Guild

As the spectre of omicron looms large over the festive season, governments around the world are desperately trying to deploy Covid-19 booster shots in order to bolster people’s protection against the more transmissible variant.

It’s been less than a month since the new, heavily mutated Covid omicron strain was detected and designated a “variant of concern” by the World Health Organization. 

Before this, studies had shown that the immunity provided by Covid vaccines waned after around six months — meaning that booster shots are essential to increasing protective antibodies to fight a potential infection.

Unless there are strong reasons such as having had a severe allergic reaction or other side-effect previously, Pfizer or Moderna are preferred. The mRNA vaccines appear to be more effective as a booster dose compared to other COVID vaccines because they give the highest uplift in antibodies.

Research suggests that 20 weeks after their second jab, people over 65 were only 37 percent protected against symptomatic COVID if they had been given the AstraZeneca vaccine. If they had been given Pfizer, it was 55 percent with  estimates for protection against hospitalisation being 76 percent and 91percent respectively.

With omicron, protection is believed to be lower because of its mutations. Further research suggests that vaccine effectiveness against omicron more than 25 weeks after a second vaccine dose was negligible for AstraZeneca and only about 35 percent with Pfizer. But after a booster, effectiveness was around 75 percent.

Given that vaccines and boosters have shown greater effectiveness against severe disease than against infection with other variants,  protection against severe illness is much greater.

Scientists in South Africa, where omicron was first detected, found that the variant significantly reduces the antibody protection generated by Pfizer and BioNTech’s vaccine. They also found that people who had recovered from the virus and received a booster shot would likely have more protection from severe disease.

It was  concluded that “previous infection, followed by vaccination – or likely a booster – is probably protective against omicron, and almost certainly against severe disease.

It was found that a booster dose offered significant protection against the variant and noted that the initial two doses may still protect against severe disease.

More findings show that a two-dose course of Covid vaccines was significantly less effective against the omicron variant than the delta strain, but found that a “moderate to high vaccine effectiveness of 70 to 75 percent is seen in the early period after a booster dose.

Vaccine hesitancy, an avoidable threat

Although the COVID-19 pandemic has increased awareness of the importance of vaccines for the vast majority of people who accept vaccines, the apathy and hesitancy continues to grow.

A random survey conducted among Lagosians by Saturday Vanguard in June 2021 about three months after vaccination exercise commenced in the country, revealed that very few were prepared to be vaccinated. 

Many of those surveyed were either unsure or outrightly declared that they would not be vaccinated. Just this week, almost six months after when Saturday Vanguard conducted another random survey in the city, the perspective hardly changed and the outcome was near identical to what it was in June.

This was not surprising because despite the increase in the overall number of vaccinated persons, the rate of vaccination per population fell far short of target. The COVID-19 vaccine hesitancy had already gained ground to become an issue that needed to be addressed. 

The WHO defines vaccine hesitancy as the delay in the acceptance of blunt refusal of vaccines, despite the availability of vaccine services. While it is a growing trend vaccine hesitancy represents a threat that is seriously jeopardising the implementation and success of Nigeria’s COVID-19 vaccination campaign. 

It is not difficult to determine why Nigerians are shunning vaccination. Experts attribute it to several factors ranging from doubts about the existence of the coronavirus itself, concerns about the origin of the vaccines, myths and misconceptions about the safety and efficacy of vaccines, religious beliefs, complacency, mistrust of the vaccine industry and the healthcare system, amid other personal or generalised idiosyncracies. 

From its findings, Saturday Vanguard gathered that the rapid pace of vaccine development is one of the component reasons undermining vaccination confidence and increasedbcomplacency about the vaccine.

COVID-19 vaccine hesitancy may be aggravated in African countries, as a result of many theories on social and traditional media. 

Despite the potential benefits presented by the COVID-19 vaccine, experts say the reluctance of many to be vaccinated is ultimately limiting the effectiveness of the nation’s pandemic response. 

The federal government says it plans to fully vaccinate 40 percent  of its citizens against COVID-19 before the end of 2021, and 70 percent  by the end of 2022.

Lagos is the epicenter of the pandemic even with the most proactive health care in the country with emphasis on primary health care and insurance.

Majority of those encountered expressed some hesitancy with respect to the COVID-19 vaccines, due to perceptions. Contributory factors include the negative campaigns targeted at discrediting the vaccines and querying its safety and necessity.

Although there were efforts to debunk these misconceptions and misinformation, the general disbelief in the existence of COVID-19, and relevance of the vaccines remain significant. 

Experts that address these concerns about the vaccines, always assure that the benefit outweigh the associated risks. Most of the side effects are mild or moderate, and although there is evidence of severe adverse effects, these are the exceptions and are quite rare especially when viewed in relation to the public health benefits. The need for continuous enlightenment of the public about vaccine safety cannot be overemphasized. 

In the view of the President of the Nigeria Medical Association, MMA, Prof Innocent Ujah, more Nigerians need to be innoculated against the virus toward achieving herd immunity quickly.

Ujah said there are vaccine doses to inoculate more people even as he stressed the need to overcome vaccine hesitancy which he attributed to being fueled by mistrust, complacency, fear and misinformation. 

The Federal government imposed a December 1, 2021 deadline for civil servants to be vaccinated against COVID-19. Similarly, Edo and Ondo states recently announced compulsory COVID-19 vaccinations for adults. The uproar following these declarations are yet to die down. 

There are arguments that such mandatory COVID-19 vaccination is illegal without legislation or regulation and if imposed, would amount to violation of citizens’ right to privacy, right to movement and right to religious life.

Health watchers argue that even though COVID-19 vaccination is desirable, mandatory vaccination may not automatically attain high vaccination rates. 

Public information, education and communication are crucial towards dealing with vaccine hesitancy.  vaccination rates. Research into how to further improve uptake rates among vaccine-hesitant citizens is more important than mandatory vaccination.

Needle-free Covid-19 vaccine debuts

A new needle-free vaccine, developed by the University of Southampton using DIOSvax technology that is under trial in the UK, uses a jet of air to push through the skin rather than a needle and differs from the mechanism found in Pfizer and Moderna vaccines.

Saul Faust, clinical chief investigator and director of the National Institute for Health Research (NIHR) Southampton Clinical Research Facility, said: “This isn’t simply ‘yet another’ coronavirus vaccine as it has both COVID-19 variants and future coronaviruses in its sights. This technology could give wide-ranging protection to huge numbers of people worldwide.

Professor Jonathan Heeney at the University of Cambridge, who helped developed the vaccine with research company DIOSynVaxv said: “As new variants emerge and immunity begins to wane, we need newer technologies. It’s vital that we continue to develop new generation vaccine candidates ready to help keep us safe from the next virus threats.”

While most existing COVID-19 vaccines use mRNA technology to target the spike protein of virus samples found in January 2020, DIOSvax aims to predict how the virus could mutate, allowing it to target emerging variants.

“DIOS-CoVax vaccines target elements of the virus structure that are common to all known ‘beta-coronaviruses’ – those coronaviruses that are the greatest disease threats to humans. These are structures that are vitally important to the virus life cycle, which means we can be confident that they are unlikely to change in the future,” Heeney explained. 

“These next generation DIOSvax vaccines should protect us against variants we’ve seen so far – alpha, beta, delta variants, for example – and hopefully future-proof us against emerging variants and potential coronavirus pandemics.”

It is hoped that the needle-free mechanism will additionally help those with needle phobias receive full COVID-19 vaccination. If successful, the technology has the potential to be scaled up and manufactured as a powder to boost global vaccination efforts, particularly in low- and middle-income countries.

Vanguard News Nigeria