KUALA LUMPUR, Oct 6 — As anticipation grows with results of human trials of at least one of the Covid-19 vaccine hopefuls coming out this month, public health experts are counselling caution and adherence to current precautionary measures for the foreseeable future.

The world recently crossed the one million mark in terms of Covid-19 deaths, making an effective and safe vaccine even more imperative. In Malaysia, cases are on the rise again, sparking fears of another wave.

Results of human trials by Pfizer are expected as early as this month, while many other vaccine-makers expect to know whether their product works by the end of the year.

There are over 150 vaccines in various phases of development, according to the World Health Organisation (WHO).

However, WHO representative to Malaysia, Singapore and Brunei Dr Ying-Ru Jacqueline Lo reminded the public not to expect a vaccine until mid-2021 at the earliest.

"We are expecting that sometime later next year, we will have a Covid-19 vaccine — a safe and effective Covid-19 vaccine available. Having said that, the vaccine alone will not be the solution. The vaccine has to be available in the quantities we need,” she told Bernama in an interview recently.

She said any vaccine that is approved by the WHO under the Covax facility, an initiative of over 172 countries to procure and provide an effective vaccine to at least 20 per cent of the members’ population, has to undergo other steps before it can reach the masses. 

Long road ahead

Eleven vaccines, three of them included in the Covax facility, are currently undergoing Phase Three trials, where thousands in many countries get inoculated while some receive a placebo. 

Malaysia announced on Sept 19 that it would be joining Covax, with Science, Technology and Innovation Minister Khairy Jamaluddin saying that Malaysia would be negotiating bilaterally with other countries to procure vaccines.

While this sounds like good news, experts are cautioning the road from Phase Three to widespread vaccination is a long one.

For one thing, only time can ensure the safety and efficacy of the vaccine. Subjects in Phase Three trials have to go through months to see if they can get infected with the coronavirus and if so, how they respond to it.

Researchers also monitor subjects for any adverse side effects. They then compare the results to those who received a placebo, to see if there is any statistically significant difference in the data.

According to the US Centers for Disease Control, once experts deem a vaccine effective and safe, it goes into the manufacturing and quality control phases.

The whole process usually takes between 10 and 15 years, but for Covid-19, this has been compressed into about two years. Approval, however, does not mean availability. 

"It is important that the vaccine is rolled out in all countries around the world, not only some countries,” said Dr Lo.

She said even with the fast-tracking of the vaccine, there were certain steps that should not be removed, adding that respective countries’ approval bodies will have to test and approve it, on top of producing enough doses.

To be truly effective, the Covid-19 vaccine needs to have a success rate of 50 percent, either by preventing infection or by reducing the severity of the disease. It also needs to have 60 or 70 percent coverage among the population. 

WHO has said the first groups to be vaccinated should be healthcare workers, and high-risk groups such as the elderly and people with health problems. Others will have to wait.

All this talk of caution and delays in the distribution has not dampened the Malaysian public’s appetite for a Covid-19 vaccine, however. 

In a poll by IPSOS for the World Economic Forum, 85 percent of Malaysians surveyed said they would take a Covid-19 vaccine if one was available. About half think a vaccine will be available by the end of the year.

Of the 15 per cent that refused to get vaccinated, almost half cited fear of side effects as a reason.

 Lessons of Dengvaxia

Public health experts say the fears of the 15 percent may be valid. With the production and approval process being sped up, there are concerns that no amount of safety trials will be enough and any adverse effects would only embolden the small but loud anti-vaccination movement in Malaysia.

"We have to try to be cautious, and at the same time we don’t give a bullet to these anti-vaxxers,” said Malaysian Public Health Physicians Association president Datuk Dr Zainal Ariffin Omar.

He said no one wanted a repeat of the Dengvaxia incident, where the dengue vaccine in the Philippines in 2017 was found to have possibly caused the deaths of hundreds of schoolchildren. 

Its maker Sanofi Pasteur found the vaccine could exacerbate the effects of a dengue infection within people who never had the disease, but only after the Philippine government had inoculated millions of schoolchildren. 

Dengvaxia has been blamed for falling trust in vaccines in the Philippines, which then contributed to an outbreak of measles last year. 

The vaccine, which had been in the works for over 20 years before being approved for use, is now recommended only for people who have had dengue previously.

Malaysian Medical Association former president Dr N. Ganabaskaran, however, thinks the trend would go the other way, saying Covid-19 has increased support for vaccines.

"Normal people we’re talking to, they know the vaccine is very important,” he said.

 Old is new again

So what should people do when a vaccine is available but they cannot or do not want to get it?

Rely on the old tried-and-tested methods of preventing disease, as in physical distancing, hand-washing and movement restriction, say public health experts.

Dr Zainal said the vaccine should not be considered a cure-all but rather a complementary way to combat the disease.

"Keep doing what we’ve been doing until we’re sure of the vaccine,” he said.

Dr Lo agreed. 

"We have seen what works,” she said, adding that self-discipline works against other diseases too.

"It is always good. It prevents many things. Transmission not only of Covid-19, but influenza and other infections which are transmitted through respiratory droplets,” she added. — Bernama