By Sola Ogundipe
A new clinical trial has found that giving people just one-fifth of a yellow fever vaccine is as effective as the full dose. This means that more lives can now be saved during outbreaks of the deadly disease.
The study was led by Epicentre – the research arm of Médecins Sans Frontiéres / Doctors Without Borders, MSF, with the findings published in the medical journal The Lancet.
The results showed that reducing the standard yellow fever vaccine dose was both effective and safe, prompting the World Health Organisation, WHO, to change its official guidelines on the disease.
This will make it easier for governments and international aid organisations to prevent people from getting sick from yellow fever during outbreaks or vaccine shortages.
The Epicentre study, in collaboration with the Kenya Medical Research Institute, Institut Pasteur de Dakar, and the WHO took place in Uganda and Kenya between November 2017 and February 2018.
During this period, researchers administered either one fifth or a standard dose of the yellow fever vaccine to 960 adults between the ages of 18 and 59 years old. People receiving one-fifth of the dose were found to have an immune response that was considered equal to the standard dose.
The study was conducted as a “randomised, double-blind” trial – meaning neither staff nor patients knew which dose was being given and when – to achieve unbiased results.
“This research is significant because it shows that trials involving different manufacturers, where their products are independently evaluated, is possible,” said Rebecca Grais, research director of MSF’s Epicentre.