Washington, Jul 19 (IANS): The US National Institutes of Health (NIH) has invested nearly $29 million in the last two years to breed more monkeys for biomedical research, Nature reported.

The funding is been used to refurbish housing, building outdoor enclosures and making other infrastructure improvements at the US National Primate Research Centers (NPRCs).

The NIH is expected to spend another $7.5 million by October. The US government has proposed a 27 per cent increase in funding for the NPRCs in its budget request for fiscal year 2022. If approved by Congress, that would add $30 million for the centres, the report said.

The aim is to balance an ongoing shortage of these animals, which grew worse in 2020 as scientists tested scores of Covid-19 vaccines and treatments on primates before trials began on people.

"We have been making investments to bring the levels up and to plan for the future," James Anderson, director of the NIH Division of Program Coordination, Planning, and Strategic Initiatives in Bethesda, Maryland, was quoted as saying.

"What happens if [a pandemic] happens again, with another virus in three years? We want to be ready for that," he added.

US scientists use non-human primates, most commonly rhesus macaques (Macaca mulatta), to study a range of medical conditions, including infectious diseases. Genetically and physiologically similar to people, primate models offer a way to run tests and experiments before human trials or when human trials are not possible. In 2019, US scientists used 68,257 non-human primates in research, according to the US government.

"A couple of years ago, we were feeling the pinch," Nancy Haigwood, director of the Oregon NPRC in Beaverton, which houses about 5,000 non-human primates, was quoted as saying. But owing to the pandemic, "we are truly out of animals", she added. "We're turning away everyone."

While experts stated that the new funding is a step in the right direction, it will take a bigger investment to fully address the shortage, they noted.

"It's very encouraging to see the Biden administration make an investment in the future of primate research in the US," said Matthew Bailey, president of the National Association for Biomedical Research (NABR) in Washington DC -- a group that advocates support for animal research.

But he added that it takes time to establish monkey colonies, and yields could be years away.