Synthetic vaccine to combat epidemics

A new vaccine developed against the mosquito-borne virus Chikungunya, which can be stored at warmer temperatures and negates the need for refrigeration, could mark a major advance in vaccine technology. The vaccine, which was engineered using a synthetic protein scaffold, could probably revolutionise the way vaccines are designed, produced and stored in the future.

Vaccination has proven to be an exceptionally powerful medical tool in the fight against infectious diseases that decimate populations in many parts of the world. Vaccinations have helped eradicate smallpox from the world, and aided in constraining measles, polio and tetanus. However, severe challenges to human health persist, evidenced by epidemics caused by Ebola, Zika and others. This is particularly severe in developing countries which often lack adequate infrastructure and resources to prevent or manage outbreaks, bringing about disruption and damage in affected communities and massive economic shortfall.

A recent example is Chikungunya, a virus transmitted by the bite of an infected mosquito. The disease causes crippling headache, vomiting, swelling of limbs and can lead to death. Even if a fever ends abruptly, chronic symptoms such as intense joint pain, insomnia and extreme prostration remain. Formerly confined to sub-Saharan Africa, Chikungunya has recently spread worldwide as its mosquito host leaves its natural habitat due to deforestation and climate change, with outbreaks reported in the US and Europe.

Researchers from the University of Bristol and the French National Centre for Scientific Research (CNRS) in Grenoble, France, teamed up with computer technology giant Oracle to find a way to make vaccines that are able to withstand warm temperatures (thermostable), can be designed quickly and are easily produced.

The team worked with a synthetic protein that forms a multimeric particle resembling a virus but is completely safe as it has no genetic material inside. The scientists were completely surprised to find that this particle also remained incredibly stable even after months, without refrigeration.

The particle with its flexible surface allowed the scientists to insert small, harmless bits of Chikungunya to generate a virus-like mimic that they could then potentially use as a vaccine.

Tests using the particles on animals have yielded exceptionally promising results and have set the stage for a future vaccine to combat Chikungunya in humans.

The vaccine candidate is easy to manufacture, extremely stable and elicits a powerful immune response. It can be stored and transported without refrigeration to countries and patients where it is most needed. Intriguingly, the scientists said they could very rapidly make similar vaccines to combat many other infectious diseases.