H1N1 Found in Elephant Seals
May 16, 2013

Elephant Seals Test Positive For H1N1 Swine Flu

Brett Smith for redOrbit.com - Your Universe Online

Swine flu can now officially be considered a misnomer for H1N1, as a team of American and Chilean scientists have identified it in a population of northern elephant seals living off the coast of central California, according to a new report in the journal PLOS ONE.

In an attempt to understand how viruses surface and move among species, the study authors from the University of California, Davis have been investigating flu viruses in wild birds and mammals since 2007.

"We thought we might find influenza viruses, which have been found before in marine mammals, but we did not expect to find pandemic H1N1," said lead author Tracey Goldstein, an associate professor with the UC Davis Wildlife Health Center. "This shows influenza viruses can move among species."

From 2009 to 2011, researchers tested over 900 nasal swabs from 10 different species of marine mammals living off the North American Pacific Coast. They positively detect H1N1 in two northern elephant seals as well as an immune reaction — a sign of exposure — to the virus in an additional 28 seals. None of the seals appeared to have symptoms.

According to Goldstein, the findings should come as a warning to those responsible for handling marine mammals. When H1N1 first appeared in 2009, it became clear that those who were regularly exposed to pigs were at the greatest risk of contracting the virus.

"H1N1 was circulating in humans in 2009," said Goldstein. "The seals on land in early 2010 tested negative before they went to sea, but when they returned from sea in spring 2010, they tested positive. So the question is where did it come from?"

The seals were fixed with satellite tags, allowing the researchers to know where they had been upon returning to the coast. One infected seal traveled from California to southeast Alaska and returned to Point Piedras Blancas near San Simeon, California from February to April of that year. The other seal that tested positive left San Mateo County in early February and headed to the northeast Pacific before returning in May.

The report said the seals were likely exposed to the virus before they returned to land, as both were tested within days of coming near the shore.

"The study of influenza virus infections in unusual hosts, such as elephant seals, is likely to provide us with clues to understand the ability of influenza virus to jump from one host to another and initiate pandemics," said co-author Adolfo Garcia-Sastre, a microbiology professor at the Icahn School of Medicine.

The virus began appearing in April 2009 in parts of the US and Mexico. It appeared to spread rapidly with almost 2,100 diagnosed cases by May 7, despite extensive prevention measures enacted by both the US and Mexican governments. In June, the World Health Organization (WHO) declared an H1N1 pandemic, the first global pandemic since 1968. In 2009, President Barack Obama declared H1N1 a national emergency.

However, after becoming a worldwide pandemic and national emergency, the WHO currently considers H1N1 a controlled seasonal virus.