New Hampshire remains free of a variant of mad cow disease that is sweeping through populations of deer and elk in many parts of the country, protected in part by distance and our relative lack of hunting preserves, according to test results collected by the state.
“It’s not a surprise, but it’s always a relief,” said deer biologist Dan Bergeron of New Hampshire Fish and Game after the finding was released Wednesday.
For 16 years, New Hampshire has been testing tissue samples from deer brought to check stations by hunters during the fall hunting season, looking for signs of chronic wasting disease, a contagious brain disease that is fatal to deer, elk and moose. In 2017, 444 tissue samples were tested by a federal lab, and all proved negative.
New Hampshire’s monitoring program is part of a nationwide effort. Since it began in 2002, 6,261 deer have been tested in New Hampshire.
Despite the good news, Bergeron noted that CWD continues to spread in other parts of the country and unless something changes, it is likely to show up in New Hampshire.
“Eventually, I think it will be everywhere,” he said. “We are buffered a little bit, still separated by other states.”
CWD is a contagious neurological disease similar to mad cow disease or scrapie in sheep, spread by an abnormal protein known as a prion. It has not been shown to infect humans.
It is found in 25 states and two Canadian provinces, with its closest sighting in Pennsylvania and New York state. The latter had one small outbreak that appears to have been eradicated; no CWD has been found in New York since 2005.
CWD has often shown up in preserves, where deer or elk are kept to be hunted, presumably because the population density is higher and contamination can spread more easily. New Hampshire does not allow such preserves except for Blue Mountain Forest Association, a 26,000-acre hunting preserve in Newport often called Corbin Park, which predates the ban.
The disease is most easily spread through contaminated parts of a sick animal, especially the brain and spinal cord. That is why many states prevent deer carcasses from being carried across state lines from areas where CWD is found or suspected.
The laws can make transporting deer carcasses complicated. New Hampshire does not forbid importing deer carcasses from New York, because of the lack of recent CWD, but both Vermont and Massachusetts do forbid it. As a result, a New Hampshire hunter bringing a deer back from New York is breaking the law when traveling through those neighboring states; Fish and Game recommends that hunters debone their deer in New York before coming back.
Fish and Game also recommends that hunters who sprinkle scented lures to attract male deer during breeding season should not use natural lures, which are based on urine collected from deer in pens. The concern is that CWD prions may be spread by the urine, particularly because there is little regulatory oversight of the industry making the lures. Some states, including Vermont, have banned their use.
This position is opposed by many hunters, who say there is no evidence CWD can be spread by the urine-based lures, which are said to be far more effective than synthetic lures.
The origin of CWD is unknown. It was first recognized in the late 1960s as a syndrome in captive mule deer in Colorado wildlife research facilities, and it may have been present in free-ranging populations of mule deer for more than 40 years.
For more information on CWD in New Hampshire, see the website wildnh.com/wildlife/cwd.
(David Brooks can be reached at 369-3313 or dbrooks@cmonitor.com or on Twitter @GraniteGeek.)