The jury is still out on Covid-19 vaccine effectiveness

Emeritus Professor Tan Sri Dato' Dzulkifli Abdul Razak
Opinion - New Straits Times
December 9 , 2020

THE recent report of a death involving a priest in a Covid-19 vaccine trial must have jolted the world that is expecting much from the touted "vaccine race". Allegedly, he passed away after participating in a vaccine trial in the US.

The breaking news came from a church announcing the death at his home.

The cause behind his death is unclear, perhaps due to a heart attack at the age of 70. The priest received his first injection in August. His test for Covid-19 was said to be negative. Half of the participants received the experimental vaccine and the remaining half a non-drug entity (placebo) of saline solution.

The participants and the study team were not informed as to who received the vaccine or the placebo. The injections, however, were coded for purposes of the study.

"During the first week, each day I had to report my temperature and any symptoms — fatigue, nausea, injection site pain, arm swelling, chills, fever or headaches. I had none," the priest reported.

In October, he was given the second injection, and another Covid-19 test was conducted, which also gave a negative result. No symptoms were reported.

His next evaluation was to take place early next year. All along, the priest seemed to have no concern about the risks.

He was among 30,000 volunteers in a US study that is racing to deliver Covid-19 vaccines. The politics of the then US presidential election allegedly had some interest in the outcome.

The expectation was to provide maximum protection against the virus, which is wreaking havoc with millions of American lives.

When a vaccine is claimed to be 95 per cent effective, this means that among 100 people who received it and were then exposed to the virus, 95 would be unlikely to get sick. Five people would be at risk of still developing the infection, though these five susceptible individuals could have milder infections compared with those who did not receive the vaccine.

The protection afforded by vaccines is not all-or-nothing. Nevertheless, it is not easy to eliminate the pandemic in one go, even if the vaccine is made available globally for public use. The vaccine, per se, is not perfect.

Furthermore, the body's immune system takes time to be ready to provide protection. In addition, the vaccines could be less effective than cited as the population receiving it grows.

Moreover, while the clinical trials are carefully set up, the possibility that the virus has evolved cannot be ruled out, such that less benefits are seen from its application.

To achieve herd immunity, more time is needed for enough vaccines to be made and administered to the population. The most hazardous hurdle for the injection is yet uncertain, namely, challenging the participants with wild Covid infection.

At this stage, past experiences at developing Covid vaccines have always faltered as both humans and animals, while achieving robust antibody response, grew sick and died when exposed to the wild virus.

At this juncture, it is useful to remember what Ken Frazier, the chief executive officer (CEO) of a well-known pharmaceutical company, Merck, said in October, "that drugs to treat or prevent Covid-19 aren't a 'silver bullet' solution to the pandemic. I think it'll be with us for a while, and I would say certainly well into next year we'll still be trying to observe these public health measures".

According to his assessment, a potential vaccine will not likely be widely available for people until the middle of next year. Earlier, Frazier reminded the world that vaccine development takes time, typically a decade.

To hope for an effective and viable vaccine against the novel coronavirus by the end of December is, therefore, premature.

Reportedly, in a June 30 interview with the Harvard Business Review, as recorded by Reuters, Frazier warned that vaccines may not have the qualities necessary to be deployed rapidly and on a large enough scale as politically promised.

"If you're going to use a vaccine on billions of people, you better know what that vaccine does," he said in the interview.

Now with the tragic death of the priest, it is imperative to deeply reflect on what the Merck CEO said. The jury is still out.

The writer, a 'New Straits Times' columnist for more than 20 years, is International Islamic University Malaysia rector