Sea otters living off the coast of Washington state in America were infected with the same H1N1 virus that caused the global ‘flu pandemic in 2009.
The study, carried out by the US Geological Survey (USGS) and Centers for Disease Control and Prevention, found evidence that northern sea otters were affected by human ‘flu.
Researchers discovered antibodies for the 2009 H1N1 ‘flu virus in 70% of the sea otters studied, but it is unclear how they were exposed.
The animals showed no visible signs of sickness, but the presence of antibodies means the otters were previously exposed to influenza.
Zhunan Li, a scientist at the Centre for Disease Control, said: “We are unsure how these animals became infected. This population of sea otters live in a relatively remote environment and rarely come into contact with humans.”
LeAnn White, USGS scientist, said: “Our new study identifies sea otters as another marine mammal species that is susceptible to influenza viruses and highlights the complex interspecies transmission of ‘flu viruses in the marine environment.”
The study is published in the journal Emerging Infectious Diseases.