Challenges abound but herd immunity still possible

vaccination elderly

By Nina Muslim

KUALA LUMPUR: In these Covid-19 times, herd immunity has become this buzzword that signals freedom, normalcy and safety all in one.

Malaysia is set to focus solely on herd immunity within a few weeks once vaccinations for the general public begin under its National Covid-19 Immunisation Programme (PICK), instead of targeted populations, such as the elderly and the disabled.

However, obstacles remain, such as vaccine hesitancy, inequitable access and possible coronavirus mutations that render the vaccines useless. How well Malaysia does in tackling the challenges will determine when and to which degree normal life will resume.

But first, what is herd immunity and why do we need it?

Dr Megat Mohamad Amirul Amzar Megat Hashim, an executive committee member of Medical Mythbusters’ Strategic Planning Vaccination Campaign, described herd immunity as a set of umbrellas.

He described people who have been vaccinated, or gotten the infection and survived, as the ones carrying umbrellas. The coronavirus is the rain.

“If enough persons open up their umbrellas, it doesn’t have to be all persons … but everybody will be protected from the rain,” he said.

“(In other words,) if you achieve a certain threshold of immunity in the community, for example, 70 to 80 percent of the population is vaccinated, the protection encompasses 100 percent of the community,” he added.

However, getting to that threshold is easier said than done.

Malaysia has set the target for vaccination at 80 percent of the population or around 24 million people by February 2022, which means almost all adults and children over the age of 12 in the country need to be vaccinated.

To call the target ambitious goes without saying. So, is herd immunity a pipe dream?

Not necessarily, say public health experts. They are confident Malaysia will achieve herd immunity; the question is when. 

Associate Prof Dr Rafdzah Ahmad Zaki, a public health medicine specialist at Universiti Malaya, said vaccinations need to done as fast as possible to ensure herd immunity does not become unreachable.

“Herd immunity depends on the percentage of the population that has been vaccinated. So, the sooner we achieve high coverage, the faster we can achieve immunity. So, it depends on the availability of the vaccine and the distribution process,” she said.

In spite of some initial hiccups, Malaysia now seems to be in a good place to surpass the deadline of February 2022. For the week of June 7 to 13, an average of over 130,000 doses was administered daily. It hit a record 215,876 shots on June15, on track for hitting the 300,000 daily average target by the end of August.

Delivery of the two-dose Pfizer/BioNTech, AstraZeneca/Oxford University and Sinovac vaccines — enough to fully inoculate more than 100 percent of the population — is now more consistent. Malaysia is also planning to purchase the one-dose CanSino and Johnson & Johnson (J&J) vaccines.

But there is some concern that vaccine hesitancy may be responsible for the slow registration rate, which is 59.1 percent as of June 15, almost five months after vaccine enrolment under PICK began.

The possibility that some are reluctant to get a vaccine due to safety and other concerns has been enough of an issue that Prime Minister Tan Sri Muhyiddin Yassin recently mooted the idea of making vaccinations mandatory.

But gauging public interest in vaccinations via registration rates may not be accurate. According to a global study published by the US National Library of Medicine National Institutes of Health, Malaysia has one of the highest rates of Covid-19 vaccine acceptance in the world at 94.3 percent. Fears over Covid-19, estimated at 74 percent of Malaysians by IPSOS, may also be fuelling interest in vaccination.

The recent success of the AstraZeneca/Oxford University opt-in vaccine programme, despite over-hyped links to an extremely rare blood clotting disorder, showed many are eager to get their shot. If the studies’ findings hold, vaccine hesitancy is unlikely to be enough to hinder the country’s herd immunity goals.

What some see as vaccine hesitancy may instead be a lack of access issue.

The biggest challenge seems to be the lack of access, which the country is tackling with varying degrees of success.

On one hand, vaccination access and administration have improved, with the opening of mega-vaccination sites in urban areas to service thousands daily and drive-through sites, as well as using community, health and religious centres and deploying mobile units to rural populations, homebound residents and workers in certain industries, among others.

But on the other hand, some communities in Malaysia are in danger of being side-lined. Since most Covid-19 vaccines require two doses, hard-to-reach communities, like migrants and the Orang Asli, will find it more difficult to receive full protection.

The recently approved one-dose vaccines will help vaccinate those in the interior and rural areas, but undocumented migrants, refugees and the stateless face another hurdle; they may not be able to get vaccinated without risking arrest.

Coordinating Minister for the Covid-19 Immunisation Task Force (CITF) Khairy Jamaluddin Abu Bakar previously pledged safe passage for any migrant who came forward for their vaccine. He said embassies, non-governmental organisations (NGOs) and international organisations are aiding the government in the effort.

However, recent statements by Home Minister Datuk Seri Hamzah Zainuddin have put that into question.

At various events, Hamzah announced crackdowns against undocumented migrants. He also said undocumented migrants must surrender themselves when the time comes for them to be vaccinated.

Local leaders, NGOs and public health experts have come out against the plans. Chief of mission for the International Organisation for Migration (IOM) Kendra Rinas told Bernama it was crucial to create an inclusive environment for migrants to get vaccinated.

“IOM, as part of the UN and in coordination with other NGOs and the government, are ready to support migrant vaccinations, but migrants will not be willing to come forward if they fear arrest, detention and deportation,” she said via WhatsApp.

Datuk Dr Zainal Ariffin Omar, president of the Public Health Physicians’ Association Malaysia, agreed, saying, “The important thing is to protect these people as well as to protect the public. So, the only thing we can do is just give it. Don’t worry whether they’re illegal or not illegal.”

Activists and public health experts also hope that the recent approval of the one-dose J&J and CanSino vaccines can reduce red tape and make it easier to vaccinate migrants. Dr Zainal said the government should provide the vaccines to NGOs that are willing to do the work to vaccinate the migrant communities.

Whether the government ultimately decides to follow the advice of social, medical and public health experts remains to be seen.

The last main obstacle getting in the way of herd immunity is something that Malaysians cannot fully control: the emergence of new variants that may be able to evade vaccine protection.

Dr Rafdzah said the risk came if vaccination was delayed or if not enough people got their shot.

“If we delay the process … the infections will increase. When we have more transmissions within the community, you have more new variants. It may be one day; the vaccine might not be as effective on the new variant. Then the time to achieve herd immunity will take longer as we look for a new vaccine,” she said.

But even if Malaysia reaches its vaccination targets by the end of the year, it may not be enough to outpace the coronavirus’ mutation rate as other countries struggle to secure enough supplies or vaccinate their people.

The Delta variant, formerly known as the Indian variant, is fast becoming the dominant strain worldwide as it is more infectious. It has also shown it is able to evade some antibody protections, which means vaccines will be less effective in preventing infection and transmission compared to previous strains.

However, this does not mean we should not get the shot.

Molecular virologist Dr Vinod Balasubramaniam of the School of Medicine, Monash University Malaysia, said the new variant has made vaccination even more crucial to prevent death. In the UK, most of the deaths related to the strain were among the unvaccinated.

“Vaccines are the only way out, despite the emergence of all these variants. We have to reduce susceptible hosts for the virus. The virus will find it really hard to infect and grow and transmit from one person to another person if the person is vaccinated,” he said.

The government recently approved the Pfizer vaccine for children aged 12 and above, increasing the likelihood that Malaysia reaches its herd immunity target soon.

“Vaccinating the younger population definitely will help us achieve herd immunity. Those above 18 only represent about 70 percent of the population and we would never reach herd immunity if we just focused on those over 18,” said Dr Rafdzah.

But experts do not see a return to pre-Covid normal even if we hit the magic number. Vaccines protect against death and severe infection but it is still possible to get infected and transmit the disease even if vaccinated. Scientists are also not sure how long the protection will last.

There is also the issue of uneven vaccination rates in the world.

Dr Megat Mohamad Amirul said until the world reaches the same level of protection, there will always be pockets of Covid-19 outbreaks, especially in rural areas where communities may not have achieved complete coverage.

“When we’re talking about herd immunity, we’re not talking about total eradication of the virus. I foresee that total eradication of the virus is not something feasible,” he said.

Dr Zainal said this meant that although vaccinated people may be able to get close to living a normal life, those who are unvaccinated whether by choice or necessity would not be able to participate.

“We cannot expect normal but near to normal … For a certain group of people, those vaccinated and healthy young people can go around but for the vulnerable group, they still have to be cautious of public places and adhere to SOPs (standard operating procedures),” he said.

This does not mean everyone will remain in lockdown till then, however.

Experts agree some semblance of normal can return before we hit the 80 percent vaccinated figure, akin to life under the Recovery Movement Control Order last year where interstate travel, small gatherings and most social activities were allowed to resume albeit with some restrictions.

They also say lifting restrictions should depend on the percentage of people vaccinated rather than the number of cases, pegging it at around 50 percent fully-vaccinated rate.

But life may never return to pre-Covid levels.

Dr Vinod expects the coronavirus to continue mutating, turning into something akin to seasonal flu, which can still kill the weak and frail. Annual Covid-19 booster shots may then become a fixture to protect against new variants.

“I feel that it is here to stay. The goal of a virus is not to kill its host immediately. It needs to remain relevant, to stay within the community,” he added. – Bernama