Human vaccine against Rift Valley fever virus urgently needed

19 Jul 2019 | Back to News, Publications and Annual Reports

The Rift Valley fever virus (RVFV), transmitted by mosquitos, is relatively unknown in Europe but it can still pose a serious danger to both humans and farm animals on our continent. The development of better and safer vaccines is urgently required to prevent outbreaks. 

The Rift Valley fever virus is among the top 10 pathogens for which the development of vaccines is urgently required, according to the World Health Organization. This virus is now chiefly found in Africa but laboratory research shows that our European mosquito can also transmit the virus. So it’s possible that the Rift Valley fever virus could break out in the Netherlands at any moment. And this could lead to huge (economic) damage.

Fatal to 1 in 10 people

This is because the Netherlands is a densely populated country with a large number of farm animals. Infection is almost always fatal in young cows, sheep and goats, and in pregnant animals it usually leads to a miscarriage. If humans are infected, then the virus proves fatal to about 1 in 10 patients. The best way of limiting damage is through a specially developed vaccine against this virus. 

An effective vaccine trains the immune system to recognise and quickly neutralise the virus. Currently the only available vaccines are intended for animals. Due to unacceptable safety risks these vaccines are not suitable for humans. A further disadvantage of the current animal vaccines is that, if an outbreak of the disease is suspected, laboratory tests can’t distinguish between the blood of an infected animal and of a vaccinated animal. 

Non-animal test methods not yet available

So there are strong reasons for developing better and safer vaccines, ensuring that people and animals have better protection against this dangerous virus. Something also emphasised by the national and international authorities in the field of epidemiology. These bodies believe that the scientific community needs to prepare for this deadly Rift Valley fever virus and they have provided funds for corresponding research.

So far, there are no non-animal test methods available for testing the effectiveness of potential new vaccines. Our only option for carrying out these studies is with an animal model using animals which are susceptible to the virus but also have an efficient immune system. This is why BPRC researchers have set up a Rift Valley fever virus model in primates.

Antibodies protect against infection

Primates are not humans, but just like humans their immune system responds to a vaccine by producing antibodies. If a new vaccine works well in a proof-of-concept study like this, then the antibodies will protect against infection. And then researchers can further test the vaccine in people.
Would you like to read more about the Rift Valley fever virus and the need for a good vaccine for people and animals? Then go to the website of the Coalition for Epidemic Preparedness Innovations (CEPI)