A fresh outbreak of brucellosis in India serves as a stark reminder of the need for effective control measures against brucellosis in cattle.
In July, more than 50 cows were reported infected with brucellosis in the town of Tirumala. This follows a similar outbreak in February, during which a dozen cows contracted the disease.
The infected animals were segregated in order to prevent further infection by the disease – which, as a highly contagious zoonosis, can spread quickly humans. An estimated 500,000 new human cases are reported worldwide annually, with a World Health Organization report attributing around 400,000 of these specifically to food-borne routes.
Sascha Al Dahouk, Scientific Director at the German Federal Institute for Risk Assessment in Berlin and Professor for Internal Medicine at the RWTH Aachen University, says such outbreaks serve as a reminder of the need to introduce control via means of an effective vaccine.
“We have these highly endemic regions where it's very important to introduce control. This control is mainly based, at the beginning, on vaccination. Afterwards, when it is controlled, surveying and culling is the better model, but at the beginning in the high endemic regions vaccination is definitely needed.”
Dr. Al Dahouk adds that brucellosis can easily transfer from livestock to humans via the food chain.
“Taking Brucella melitensis in goats, as an example, if people consume unpasteurized milk or cheese from goats infected with brucellosis, there is a very high likelihood of contracting the disease,” he says.
Brucellosis can also result in decreased productivity – and is endemic in a number of developing countries. The toll on smallholder farmers in South Asia and sub-Saharan Africa is particularly devastating, since cattle and small ruminants, such as goats and sheep, are a crucial source of income for this population. The annual impact of brucellosis to smallholder farmers in South-East Asia and Sub-Saharan Africa alone is estimated at US $500 million per year.
Dr. Al Dahouk says further hotspots have been identified in the Mediterranean area and the Arabian Peninsula.
“This is only what we know at the moment,” he says. “There are a lot of white spots on the map in Africa, some parts of South America where we do not know whether brucellosis is endemic – more specifically in goats and sheep, or in cattle.”
The impact on human and animal health are key drivers behind a global initiative to incentivize the development of a new vaccine to control Brucella melitensis. The AgResults Brucellosis Vaccine Development Prize is a US $30 million competition designed and funded by AgResults (a collaborative initiative between the governments of Australia, Canada, the UK and the US as well as the Bill & Melinda Gates Foundation), and implemented by the Global Alliance for Livestock Veterinary Medicines (GALVmed). Aiming at a One Health solution, AgResults is looking for animal health innovators to develop and register a vaccine that is safe, efficacious and viable for use against Brucella melitensis in small ruminants across the developing world.
Three first stage prizes of US $100,000 have recently been awarded to pharmaceutical, biotech and academic organizations across the world based upon their applications; seven such prizes remain available in Phase 1 of the competition, which closes on 18th November 2017.
Dr Al Dahouk welcomes the competition as he believes it will push forward the idea of an ideal animal vaccine for different species, which is safe for people and livestock.
“If you stop brucellosis in livestock, you definitely stop it in humans: this is the key,” he says.