Rabies breakthrough offers fresh hope in battle against deadly virus [View all]

https://www.theguardian.com/global-development/2019/nov/15/rabies-breakthrough-offers-fresh-hope-in-battle-against-deadly-virus

Rabies breakthrough offers fresh hope in battle against deadly virus

New research raises hopes of oral vaccine for dogs, the chief source of transmission to humans

Rebecca Ratcliffe

Fri 15 Nov 2019 09.00 GMT Last modified on Fri 15 Nov 2019 09.07 GMT

Researchers have discovered a way to stop rabies from shutting down critical responses in the immune system, a breakthrough that could pave the way for new tools to fight the deadly disease.

Rabies kills almost 60,000 people each year, mostly affecting poor and rural communities.

It is hoped that the discovery could lead to new and improved vaccines, including oral vaccines for dogs – which are responsible for the vast majority of transmissions to humans.

The study, published in Cell Reports and carried out by teams at Monash University and the University of Melbourne, provides crucial information about how the rabies virus targets the body.

The researchers believe they are the first to observe how a particular protein made by the rabies virus binds to a critical cellular protein known as Stat1, halting key parts of the immune response. The discovery has allowed scientists to make a modified, vulnerable version of the virus – which could be used to make a new, safe and effective live vaccine.

“You can very specifically change the rabies virus and change the sequences and structures of the proteins,” said Dr Greg Moseley, from the Monash Biomedicine Discovery Institute, a lead author of the study. “The modified virus can still reproduce, but is no longer able to stop strong antiviral immune mechanisms,” he added. “It is weakened and also should make a very strong immune response. Used in a vaccine, this would protect against infection by the deadly virus.”

Scientists plan to test these modifications in vaccine strains against rabies. If successful – and if regulatory hurdles are overcome – a modified vaccine could be administered orally to dogs through bait.

“If you can get high enough immunity in the dog population, rabies will die out. Safe and highly effective live oral vaccinations for dogs would make a great contribution to elimination,” said Moseley.

In up to 99% of cases, domestic dogs are responsible for transmitting the rabies virus to humans, according to the World Health Organization (WHO).
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