Wild hog-borne virus causes hunting hound's death Alabama
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Author:  Buckshot [ Fri Oct 03, 2014 8:23 pm ]
Post subject:  Wild hog-borne virus causes hunting hound's death Alabama

Wild hog-borne virus confirmed as cause of hunting hound's death in Wilcox County


A 6-year-old male hunting dog died after contracting a case of pseudorabies virus from a wild hog in Wilcox County, Alabama's state veterinarian confirmed Thursday.

Dr. Tony Frazier said the National Veterinary Services Laboratory in Ames, Iowa, which is the animal version of the Centers for Disease Control, made the rare diagnosis this week after testing blood taken after the dog died Sept. 20 at Camden Veterinary Clinic in Camden.

The virus, also known as Aujeszky's Disease or mad itch, has never been transmitted to humans and does not pose a public threat, Frazier said.

Although the pig is the only natural host, the virus can infect cattle, sheep, cats, dogs, and goats as well as wildlife, including raccoons, opossums, skunks, and rodents.

Death often occurs within three days of infection in these dead-end hosts. There is no known pseudorabies cure. Despite the name, it is a herpes virus not related to rabies, so traditional rabies vaccines are useless in preventing it, Frazier said.

Preventative vaccines have been developed for commercial swine.

According to the NSVL, infectious pseudorabies virus can persist for up to seven hours in air with a relative humidity higher than 55 percent.

Other studies have demonstrated that the virus can survive for up to 7 hours in nonchlorinated well water; two days in stagnant lagoon effluent and in green grass, soil, feces and shelled corn; three days in nasal washings on plastic and pelleted hog feed and for four days in straw bedding.

Despite these potential avenues of transfer, Frazier is confident chances are low that the virus could make a comeback in the state's commercial swine operations based on the success of preventative vaccinations.

He also said those operations are limited to counties to the northern part of the state where wild hog numbers are lower and environmental conditions less favorable. Commercial swine are also confined to indoor facilities and farmers use additional fencing to eliminate the possibility that wild hogs and domesticated stock come into contact.

Alabama's commercial swine industry has been certified free of psuedorabies virus and brucellosis bacteria since 2000. All other states have been similarly certified.

Frazier said, however, that pseudorabies and brucellosis are endemic in the state's expanding wild hog populations.

"If we were able to test all the wild hogs in the state, We'd likely find that a large majority of them are carriers of the pseudorabies virus while maybe 10 to 15 percent would be positive for brucellosis," he said.

Why the infection rate among dogs used to hunt hogs is so low likely rests in the fact that the dog has to encounter a pig that is actively shedding the virus at the time, he said.

The dog's owner, Quintin Pearson of Pine Hill, said he had hunted the plot hound/cur mix named "Brennel" a week prior to its death during a three-day benefit hog rodeo held in and around Wilcox County's Possum Bend community.

Immediately after the hunt during which the dog was involved in 13 hog kills, Pearson traveled out of the county, leaving the dog and its kennelmates in the care of neighbors.

He said all of the hogs killed appeared to be healthy, which is common in most carriers of infectious viruses in animals.

The first symptom Brennel's caretakers noticed was that his right eye was swollen. He then began scratching his head uncontrollably.

When Brennel arrived at his clinic on Sept. 18, Dr. Bill Bledsoe said he first thought the dog was simply scratching at its swollen left eye. The scratching increased until the animal's head was bloodied, so it was sedated.

Despite the sedation, Bledsoe said the scratching worsened overnight to the point that by Friday morning, the dog had removed most of the skin on the right side of its head. At that point, Bledsoe anesthetized Brennel to prevent further self-trauma.

By that evening, Bledsoe said Brennel continued trying to scratch, but its vital signs were also deteriorating. Brennel died sometime during the night.

After doing some research that Monday, Bledsoe began to suspect that the dog may have been infected with pseudorabies. He reported his suspicions to Frazier's office as required and drew blood to be sent to the NSVL.

In this case, Frazier said the dog could have been infected after biting the hog and swallowing its blood, by breathing in the virus when the hog coughed, swallowed some of its saliva, which becomes more prevalent during the chase or some other way.

He added that since most dogs used to hunt hogs are well-kept, physically healthy and current on all their other shots, their immune systems may naturally perform better at preventing infection.

One other reason the state does not receive more pseudorabies reports, Frazier said, is that dog owners don't know what's happening when the animal begins showing symptoms or they simply find a dead dog with a bloodied head in its kennel.

In the wake of this case, Frazier is encouraging anyone whose dog begins showing typical pseudorabies symptoms or did so before suddenly dying to take it or the carcass to a veterinarian.

Since brucellosis bacteria can be transmitted to humans, it poses the greatest risk to people handling and infected animal and all necessary precautions to prevent infection such as using gloves should be taken.

Brucellosis is rarely fatal in humans, but symptoms such as an intermittent up-and-down fever, headaches, chills, depression, profound weakness among others can last from weeks to months.

Even though wild hogs are carriers of multiple diseases, their meat is safe to eat as long as it's prepared properly.

"Don't ever eat pork unless you know it's been heated to at least 160 degrees internal temperature," Frazier said.

The U.S. Department of Agriculture lowered the recommended safe-cooking temperature of commercial pork to 145 degrees in 2011.

For Bledsoe, this was the first case of pseudorabies he's seen despite treating dozens of dogs involved in thousands of hog hunts over his 33 years in practice.

"Truthfully, pseudorabies is kind of like one of those rare cancers. It's not common, but if you have it, it's a problem," Bledsoe said. "Right now, I don't think hog hunters have anything to worry about, but next week I might see 10 cases come through the door. Who knows?" ... cart_river