The miracle of vaccines

The first vaccine was developed in 1796 by Edward Jenner, who used cowpox material to develop immunity to smallpox. According to historyofvaccines.org, the next major breakthrough occurred in 1885, almost 100 years later: the development of the rabies vaccine by Louis Pasteur.

Other vaccines developed through the 1930s (50 years later) include those against tetanus, cholera, typhoid, and TB. “The middle of the 20th century was an active time for vaccine research and development. Methods for growing viruses in the laboratory led to rapid discoveries and innovations, including the creation of vaccines for polio. Researchers targeted other common childhood diseases such as measles, mumps, and rubella, and vaccines for these diseases reduced the burden greatly,” the site says.

Polio and measles are diseases that supposedly no longer exist because of herd immunity. The Association for Professionals in Infection Control and Epidemiology says “herd immunity (or community immunity) occurs when a high percentage of the community is immune to a disease (through vaccination and/or prior illness), making the spread of this disease from person to person unlikely. Even individuals not vaccinated (such as newborns and the immunocompromised) are offered some protection because the disease has little opportunity to spread within the community.”

This is something the world will struggle to achieve for COVID-19.

Vaccines must go through extensive trials to ensure they are not only effective but also safe to use. Unlike drugs to cure, which are administered to sick people to make them better, vaccines are given to healthy people to prevent them from getting sick. And they are administered to millions of people, not just a few. So, ensuring they are safe through rigorous, no-compromise (Trump, please note) processes with no side effects is extremely important — nay, essential.

Vaccines go through four phases. Clinical development takes up three phases. The Centers for Disease Control and Prevention outlines it as: “During Phase I, small groups of people receive the trial vaccine. In Phase II, the clinical study is expanded and the vaccine is given to people who have characteristics (such as age and physical health) similar to those for whom the new vaccine is intended. In Phase III, the vaccine is given to tens of thousands of people and tested for efficacy and safety. Many vaccines also undergo Phase IV formal, ongoing studies after the vaccine is approved and licensed.”

It’s in Phase IV of post-marketing surveillance that more information on the vaccine’s safety and efficacy is collected — particularly important as it confirms whether or not side effects occur.

This is what happened with Dengvaxia, and look at the hysterical reaction it generated. Instead of accepting that this was a safe drug proven in extensive trials and Phase III tests of 29,000 people that went on for 25 months — not the few that COVID-19 is being forced through — there was a weakness that post-marketing surveillance discovered. Some people who had not had dengue before suffered more severely when they did get dengue than if they hadn’t been vaccinated—something that wasn’t uncovered in the Phase III trials and was only discovered after actual use in Phase IV. Sanofi, the manufacturer, did the responsible thing of informing health authorities worldwide.

Will we get the same mindless, hysterical reaction if subsequent market surveillance uncovers a worrying side effect from a COVID-19 vaccine?

It’s time to accept that no vaccine is perfectly safe. As long as it saves vastly more lives than it risks, it should be accepted and used. Dengvaxia has been approved and is in use in 19 countries, and has saved an estimated 1 million lives. Yet it is banned here.

Latest data from the Department of Health show that in the first eight months of 2019, there were 1,107 deaths due to dengue. Many of the 1,107 people who died of dengue would still be alive today if they’d been vaccinated. Their families might not be too happy with the Dengvaxia ban. It’s time the DOH brought Dengvaxia back on the market. And takes care in accepting and using a COVID-19 vaccine, but accepts it with the recognition that it, too, may share side effects later discovered. But they’ll almost certainly not lead to death — as lack of a vaccine will.

Email: wallace_likeitis@wbf.ph