Two new flu vaccines developed for dogs

New York, Jan 27 (IANS) Scientists have for the first time developed two new flu vaccines for canines, known as man's best friend, which may also block flu strains from being transmitted and infecting people.

In the study, the researchers used a genetic engineering technique called reserve genetics to create a live vaccine against H3N8 canine influenza virus that replicates in the nose but not in the lungs.

"The nose is where the virus first enters a dog's body, so generating an immune response there could stop the virus in its tracks," said Luis Martinez-Sobrido, Associate Professor at the University of Rochester in New York, US.

"If the vaccines were to get into the lungs, it could create unwanted inflammation in response to the live virus," Martinez-Sobrido said.

Currently, veterinarians use vaccines that include inactivated or killed flu virus, but experts say they provide short-term and limited protection.

The study published in the Journal of Virology found the live vaccine was safe and able to induce better immune protection against H3N8 canine influenza virus in mice and dog tracheal cells than a commercially available inactivated vaccine.

In a separate study, highlighted in the journal, the researchers used reserve genetics to remove a viral protein called NS1 from H3N8 canine influenza virus, which significantly weakens flu viruses so that they elicit an immune response but do not cause illness.

This approach has been used with human, swine and equine flu viruses to generate potential vaccines and was also safe and more effective than a traditional inactivated H3N8 influenza vaccine in mice and dog tracheal cells, the researchers said.

The live-attenuated vaccines will now be included for clinical trials with dogs, the researchers said.