Climate change, which is proceeding fastest at high latitudes, is causing an increase in ticks in the northern hemisphere that are harmful to reindeer, researchers say.

The leap is due to warmer weather, and carries a risk of introducing infectious diseases to reindeer populations, other animals, and humans.

Associate Professor Ann Albihn from Sweden's National Veterinary Institute and the Swedish University of Agriculture said researchers had already documented infectious diseases present in reindeers in the US and Scotland.

"We must learn more about the disease, how much warmer it has to be in an area before we get a real elevation of the risk situation," she said.

Reindeers are more susceptible to climate change as they find it hard to adapt to changing environments compared to other animals.

Associate Professor Albihn said stressed animals were also more vulnerable to infections.

"If such new infectious diseases are introduced to reindeer by insect populations extending their northern range, this may be detrimental for the reindeer herding in Scandinavia and Russia," she said.

Associate Professor Albihn is part of a five-year international study focusing on climate change and the spread of infectious diseases between humans and animals.

She said she hoped better knowledge of the distribution of insects, reservoir animals and some infectious microbes may help identify areas at risk and preventative measures could be developed.

She will be addressing a conference dealing with adaption strategies in the face of climate change in Hobart in February.