Leptospirosis can be a highly contagious disease in cattle and researchers are testing a vaccine developed years ago to judge its immunity response. David Alt at the USDA's National Animal Disease Center says they hope by studying the existing vaccine they can develop something better.

"Our studies are focusing on trying to look for some commonalities that may eventually lead us down the road to a vaccine that can be used for multiple strains and would hopefully be less expensive for companies to produce as well."

Alt says the vaccine is partially effective, but there are around 200 different strains of the disease and so a lot of work remains to be done.