How Long Does It Take To Make a Vaccine?

Ebola has broken out in the Democratic Republic of Congo and Uganda, with 223 suspected deaths and 18 confirmed deaths. With no vaccine currently available, the World Health Organization has declared the situation a public health emergency of international concern. There are multiple strains of Ebola, and while a vaccine exists for the Zaire ebolavirus, commonly known as the Ebola disease, which killed more than 11,300 people in 2014, there is currently no vaccine available for the strain responsible for the current outbreak, the Bundibugyo ebolavirus. However, work is underway on developing new drugs, with UK scientists saying that a vaccine could be ready for trials in just a few months.

So, how long does it take to make a vaccine? As the following chart shows, the Covid-19 pandemic was a turning point for vaccine development. In breakneck speed, scientists raced from the stage of first isolating the pathogen causing the disease to developing an initial vaccine and clearing it for emergency use. All of this happened in under a year, in 2020. While the speed of this turnaround was driven by multiple factors, including political willpower, global collaboration and funding, the efficacy was also a result of decades of knowledge-building and advancements in technologies such as messenger RNA and vector vaccines. According to Gavi, parallel, overlapping human trials also sped up the testing process, with social media and keen public interest making it faster and easier to recruit participants.

Other vaccines have taken far longer to develop. For example, Zaire ebolavirus was first isolated in humans in 1976, and its first vaccine was not trialed until decades later. In 2015, the vaccine rVSV-ZEBOV was finally studied in Guinea, which was experiencing new Ebola cases at the time. It wasn't until 2019 that the FDA announced the first FDA-approved Ebola vaccine - some 43 years since the pathogen was first discovered.

In multiple instances, vaccines were first tested out on the U.S. military before being made commercially available. This was the case for Typhoid fever. After the bacterium responsible for the disease was first identified and isolated between 1880 and 1884, a first vaccine was developed in 1896. In 1911, the U.S. Army then made typhoid immunization mandatory for all service members and in 1914, a vaccine was licensed for use in the general U.S. population. It was a similar story with the vaccine for Influenza, which was tested for safety and efficacy on the U.S. military before it was licensed for wider use in the U.S. in 1945, as well as the vaccine for Yellow Fever, which was used to vaccinate military personnel stationed in tropical regions of the Western Hemisphere before the drug was available to the public.

The Bundibugyo ebolavirus was officially identified and isolated in 2007.