Saturday, January 28, 2012
Wolves are susceptible to more than 100 diseases and parasites. However, all animals suffer from diseases and parasites, including humans who have more diseases and parasites than wolves. In fact, humans suffer from more than 100,000 diseases. That is 1000 times the number of diseases attributed to wolves. Therefore, it is unfair to demonize the wolf for being a mortal animal with potential health problems that all animals suffer from.
Because wolves travel great distances, they may play an important role in spreading and maintaining diseases in certain areas. Infectious diseases spread by wolves include brucellosis, tularemia, listeriosis and anthrax. Canine distemper seems to only pose a serious problem for wolves in Canada and Alaska. It is a very contagious disease caused by a microscopic virus. The disease often centers on the skin, eye membranes, and intestinal tract, and occasionally the brain. Symptoms include fever, loss of appetite, and a discharge from the eyes and nose. Diarrhea and dehydration may follow, and in the final stages seizures may occur.
Contrary to popular myth, rabies is very rare in wolves. This was not the case a century ago. Most rare cases today are caused by contracting the disease from skunks, raccoons, bats, or foxes. Ninety-eight percent of rabies today in North America is from foxes. Wolves may also suffer from rabies and are a major host for the disease in Russia, Iran, Afghanistan, Iraq and India. Recorded incidences of rabid wolves in Eurasia go far back as the 13th century. The number of cases of rabid wolves are however low when compared to other species. Wolves do not serve as primary reservoirs of the disease, but can catch it from other animals such as dogs, jackals and foxes. Cases of rabies in wolves are very rare in North America, though numerous in the eastern Mediterranean, Middle East and Central Asia. Wolves apparently develop the "furious" phase of rabies to a very high degree. This, coupled with their size and strength, make rabid wolves perhaps the most dangerous of rabid animals, with bites from rabid wolves being 15 times more dangerous than those of rabid dogs. Rabid wolves usually act alone, travelling large distances and often biting large numbers of people and domestic animals. Most rabid wolf attacks occur in the spring and autumn periods. Unlike with predatory attacks, the victims of rabid wolves are not eaten, and the attack generally only lasts a day. Also, the victims are chosen at random, though the majority of cases involve adult men.
Rabies is a disease that is cause by the rabies virus, which is a small, bullet-shaped RNA virus. Rabies is usually transmitted from one mammal to another when an infected animal bites an uninfected one, as the rabies virus is capable of dividing rapidly within the salivary glands of an infected animal. The rabies virus cannot penetrate skin by itself and the deposition of infected saliva on an animal's skin does not always mean that the animal will contract the disease. Once the virus enters an animal's body, it is usually deposited within muscle tissues, where it will rapidly multiply. Rabies viruses normally replicate in muscle or subepithelial cells. After the virus has replicated extensively within the muscle tissue, it will begin to infect the neurons in the animal's muscles or skin. Rabies viruses can bind to the acetylcholine receptor of neurons. The virus will then travel through the sensory or motor nerves to the animal's central nervous system, and will most likely then infect the animal's spinal column. The virus will then end up in the animal's brain, where it will leave inclusion bodies, called Negri bodies, in the neurons.
Initial symptoms of the disease include anxiety, irritability, depression and sensitivity to light and sound. As the disease progresses, hydrophobia (fear of water) will develop, as the animal will experience difficulties swallowing. Paralysis then occurs, which will be followed by coma, and then death. In urban settings, dogs were once the main rabies vector. Now, thanks to pet vaccination programs, rabies has become rare in domestic animals in developed countries. Wild animals, especially raccoons, foxes, skunks, jackals, mongooses, squirrels, coyotes, badgers and bats are now the main transmitters of rabies. In North America, raccoons are the largest reservoir for the disease, and 98% of all cases of rabies are found in raccoons, skunks, bats or foxes. Rabies is extremely rare in North American wolves today. In the last few decades, only a handful of wolves have died from rabies, and most have been in Alaska, where wolves are common. In 1976, rabies was suspected of causing a decline in wolf numbers in northwest Alaska, although only one wolf from the area was actually found to have rabies. In 1977, rabies destroyed one wolf pack on the Brooks Mountain Range in Alaska, although the disease did not spread to other packs. In 1990, a rabies outbreak among red and arctic foxes in Alaska spread to wolves and caused 3 confirmed and 5 suspected wolf deaths. The disease only affected four wolf packs. Theberge et al. (1994), reported that rabies was responsible for 21% of the mortality among 29 radio collared wolves that died in Algonquin park from 1987-1992, although the rabies-caused mortality occurred in three different packs during a nine month period. In 1992, the Center of Disease Control reported that there were no cases of rabies in wolves during that year.
In the Asiatic region of Russia, rabies has occurred in wolves occasionally during the past three decades. In Kazakhstan, 17 out of 54 wolves examined as part of a study that spanned from 1972-1978 were found to be carriers of the rabies virus, and in 1980, ten peasants were attacked by a rabid wolf in the Voronezh region of Russia. In 1991, 11 people were bitten by a rabid wolf near L'vov. Rabies continues to be rare in North American and European wolves. However, that was not the case during the middle ages. Rabies is thought to account for many of the numerous attacks on humans by wolves that occurred during that time period, and it is thought to account for much of the strange wolf behavior that was reported. Rabies was also common in North American wolves during the 1800's and the early part of this century, as many settlers and Natives reported encountering rabid wolves.
The wolf has been blamed for instances of the extremely severe diseases of both domesticated animals and man – rabies. Lupine rabies after a latent period manifests itself in extreme agitation and aggression. Within a very short time such a dangerously sick wolf can widely spread out of his area of activity. For example, there is a recorded episode of just such a spread of rabies among farm animals and people in Belarus in 1957 when a rabid wolf within just a day and a half roamed over a hundred miles, bit 25 people (19 seriously), some 50 farm animals, and who knows how many forest creatures. Similar occurances are not rare. Moreover, while recognizing the undoubtedly serious role of the wolf in the spread of the rabies virus to man, one must be cognizant of the incomplete research in the wolf's role in limiting the numbers of other carriers of this disease, namely, the fox. The most recent examples of rapidly spreading rabies in Europe have occurred after the wolf was long gone, in the western regions of Europe and then spreading to the east.
Efforts to control the spread of canid-related diseases to Ethiopian wolves started in the Mountains Bale in 1995, led by Dr Karen Laurenson, formerly of the Centre for Tropical Veterinary Medicine of the University of Edinburgh, UK and currently an Africa Programme Officer for the Frankfurt Zoological Society. Spill-over from sympatric dogs living in and around wolf habitat is the likely source of pathogen transmission to Ethiopian wolves. Rabies is widespread in domestic dog populations, by far the most abundant carnivores in the Bale Mountains. EWCP activities to control disease includes: vaccination of domestic dogs, monitoring of disease incidence among dogs and wild carnivores and, more recently, an emergency vaccination of wolves. Dog vaccination Since 1995: EWCP is vaccinating domestic dogs in the Bale Mountains to reduce rabies incidence in the reservoir population (over 40,000 vaccinations). Vaccination campaigns also reached the Guassa-Menz range in 2003/2004 and Delanta, South Wollo, in 2003, following outbreaks of rabies among domestic dogs in nearby areas.
In Will Graves' book "Wolves in Russia", he states that rabies-infected wolves will run for 100 miles or more, deliberately biting and infecting every animal and person it encounters. Stories abound in Russian folklore of rabid wolves entering villages and attacking and biting every cow and person not sheltered inside buildings. This is not the bite-kill-eat behavior usual with wolves, but bite, move on and bite again typical of rabies-infected wolves. Will Graves behaves much the same way as a rabies infected wolf in his book: deliberately defaming the wolf in every way possible to encourage its extinction. Why do these wolf haters not mention that humans have more communicable diseases and parasites than wolves?
Wolves also carry the Canine coronavirus, with infections being most prevalent in winter months. Endoparasites include cestodes such as Taenia pisiformis, T. hydatigena, Echinococcus granulosus, Mesocestoidea lineatus, Dioctophyme renale and the adult phase of Multiceps multiceps. Wolves may carry Neospora caninum, which is of particular concern to farmers, as the disease can be spread to livestock; infected animals being three to thirteen times more likely to abort than those not infected. Wolves suffering from tapeworms may deliberately forego eating fresh meat in favour of putrified flesh, in order to rid themselves of the parasites. Other disease and parasites include: roundworm, flatworm, mange, mites, ticks, fleas, cataracts, oral papillomatosis, tularemia, bovine tuberculosis, arthritis, cancer, rickets, pnumonia, and Lyme disease. External parasites tend to be less of a problem in the cold northern regions.
Gray Wolf populations are remarkably resilient against disease outbreaks. Wolves are resilient animals that only rarely become ill. When they do, it is most often animals weakened by hunger or injuries, or cubs whose immune systems are not fully developed. Often diseases are communicated from dogs to wolves living in the wild. Usually a wolf displaying the first symptoms of disease will leave its pack, thus preventing the sickness from spreading to its pack mates. Wolves in Russia have been recorded to carry over 50 different parasite species. Ticks carried by wolves include Ixodes ricinus and Dermacentor pictus. Although wolves are host to Sarcoptes scabiei (or mange mite) they rarely develop full blown mange, unlike foxes. Other ectoparasites include biting lice, sucking lice and the fleas Pulex irritans and Ctenocephalides canis. Endoparasites include nematodes such as Toxascaris leonina and T. canis. Wolves are also carriers of Trichinella spiralis, the prevalence of which is significantly related to age.
Mange is caused by tiny mites that attach themselves to a wolfs fur or skin, In Sarcoptic mange, intense itching is caused by the female mites' burrowing under the skin to lay eggs. In demodectic mange, the mites live in the pores of the skin and cause little or no itching. The symptoms of mange include skin lesions, crusting, and fur loss. Wolves that suffer mange in the winter are in danger of freezing to death.
Canine distemper is a contagious viral disease that affects the skin, eye membranes, intestinal tract and sometimes the brain of the animals it attacks. Initial symptoms include fever, loss of appetite and a discharge from the animal's eyes or nose. Diarrhea then follows, which will usually cause dehydration. Seizures may follow, and if the disease progresses that far, the animal will most likely die. It usually occurs in young cubs, and is more likely to kill cubs than adults.
Distemper has been reported in captive wolves since 1904, although it is rather rare in wild wolves. A few outbreaks have occurred however. Carbyn (1982) found that distemper killed three 5-8 month old wolf pups in Riding Mountain National Park, Manitoba, and concluded that distemper was the second largest known mortality factor among the wolves in the park. In 1978 and 1980, two wolves were found to have died from distemper in Alaska.
Other than the two cases described above, distemper is not a major source of mortality in wild wolves. Many wild wolves do carry the disease (for instance, 48% of 71 wolves tested seropositive for distemper in northern Minnesota from 1977-1984) although distemper is rarely fatal to wolves, particularly the adults. It is possible that pups die from the disease occasionally, as the disease usually strikes puppies that are from 3 - 9 weeks old. However, cub recruitment is usually high in North America so distemper most likely does not kill very many wild wolf cubs.
Wolves sometimes suffer from viral illnesses. Canine parvovirus was discovered in dogs in 1976 in Europe and was recognized as a disease in dogs in 1978. It is spreading to wolves as well. It is a viral disease that attacks the animal's intestines and causes diarrhea, vomiting, and, consequently, dehydration. Its origins are unknown. This disease is lethal to wolf and dog pups. Like foxes and dogs, wolves can sometimes fall ill with rabies. This disease causes meningitis and manifests itself for example by paralysis, aggression and the development of foam at the muzzle, so that the animal can no longer swallow and therefore no longer takes in any fluids. Wolves can also die of the easily communicable canine distemper, which is caused by a virus that destroys lymphatic tissues and causes a strong suppression of the immune system. It was common in dogs by 1980 and first appeared in wild wolves in 1978-1979. From 1979 on, the disease began to increase its prevalence in wolves. In the early 1980's, it was found that 26% of Minnesota's wolves had been exposed to it, and in 1980, 9 out of 18 Alaskan wolves tested seropositive for the disease. It may have been responsible for a decline in wolf numbers in Isle Royale National Park from 1980-1982. The decline occurred at the same time that an outbreak occurred among domestic dogs in the area. During the late 1980s, several wolves on the island were infectd, although it is unknown as to whether or not the disease was responsible for the decline in wolf numbers. It strikes captive wolf packs far more often than it does wild wolves. In 1983, it killed 11 out of 12 cubs and yearlings in a captive wolf pack in Minnesota. It has also killed wild red wolves: four red wolf cubs died recently in the Great Smoky Mountains National Park of parvovirus.
In the wild, the threat of tick bites, lice and flees is quite high. Most of the time, these diseases are not dangerous, but in the worst case, a tick bite can be lethal. Lyme disease, also known as borreliosis, is transmitted to humans by ticks. But this disease is also dangerous for wolves and dogs. The disease progresses over three stages. There may be changes of the skin at the site of the bite, inflammation of the joints, and damages to the nervous system.
Infectious Canine Hepatitis was first discovered in free-ranging wolves in 1974, and tests done on wolves in northern Canada and Alaska suggest that the disease can be quite common among wolves. In 1982, it was found that 100% of the wolves in the Tanana flats and Nelchina basins of Alaska had been exposed to the virus and in 1987, a study done in northwest Alaska found that only 40% of the wolves in the area had been exposed to the virus. There is no relation between the occurrence of the disease in domestic dogs and in any nearby wild wolves. It is not known if ICH is a significant cause of mortality in wild wolves.
Oral Papillomatosis is a virus infects the mouth and lips of canines and can cause swelling and infection of the lips. It can also cause small tumours to form in the animals mouth and on its lips. Symptoms can be quite mild or very severe. This disease does not kill wild wolves directly, although it has been known to kill coyotes indirectly. In coyotes, it can alter the feeding behavior of the animal and may lead to multiple secondary infections. Some coyotes who contract the disease recover from it and become immune to it.
Within the last few years wolf packs have formed, which in order to survive, have been drawn to carrion, especially to dead cattle pits where the carcasses of the dead cows have not been properly buried despite the clear directives of veterinary medicine. In such situations these wolf carrion-eaters prove to be extremely serious spreaders of infectious diseases.
Together with the sufficiently negative influence of the wolf on its biocenosis by means of its spreading of infectious diseases to both animals and people, there are also not so rare data pointing out the elimination by the wolf-predator of sickly prey. In all likelihood, such sickly prey are the source of the diseases for healthy animals who get infected through the actions of the wolf. Most likely, both sides have a point in this matter. However, up to now neither side has evaluated the problem from an economic point of view. Moreover, in the report on the wolf the culling-out role of the wolf was strongly emphasized, whereas its negative influence on nature as a spreader of disease was not discussed.
Since wolves eat the entrails of their prey, they often contract dangerous infections. Wolves are susceptible to a variety of internal and external parasites. These include at least 24 species of nematodes (roundworms), 21 species of cestodes (tapeworms), nine species of trematodes (flukes), heartworms, and three species of acanthocephalia (spiny-headed worms). Wolves are also susceptible to being infested by fleas, ticks or mites. Many parasites, such as trematodes and nematodes lodge in their bodies. Only healthy wolves are able to survive this. Most adults have few problems with this disease, but many cubs die because of it becayse they do not yet have a similarly well developed immune system. From the age of about one year on, the young wolves take care of themselves and are significantly less prone to disease.
Heartworm is a parasite that enters into the wolves' bodies and releases micro-filarial worms (threadlike worms) into the blood. These worms are transmitted to other animals by mosquitoes. The worms lodge in the heart and the blood vessels and are then able to limit the wolf's blood supply and stamina. This reduces the wolf's hunting opportunities; he becomes generally weaker and susceptible to other diseases. Mosquitoes are the major vector of dog heartworm, Dirofilaris immitis. Once the worms end up in a canine, they will mature and grow on the right side of the animal's heart and on its pulmonary arteries. Initial symptoms include detectable heart murmurs and pulse deficits. As the problem progresses, the animal's heart may become enlarged and if the the infection becomes severe (up to 200 worms have been found in some animals), blood flow will be blocked. Heart failure may result from a major infection.
Heartworm is thought to be one of the major causes of the red wolf decline that occurred in the southeastern United States during this century. It has been found in in free ranging wolves in Minnesota, and it has also occurred in captive wolf populations in the southern United States. Heartworm has not been reported in Canada or Alaska, as the mosquitoes that carry it prefer warmer climates. There are medications that can be administered to dogs and captive wolves that can prevent the disease, and it is recommended that all dogs and captive wolves living in areas where heartworm occurs be on the preventative medication.
Two species of hookworms (which are a variety of nematode) occur in free ranging wolves, Ancylostoma caninum and Uncinaria stenocaphala. A. caninum is a large blood-sucking worm that attaches itself to and abrades its host's (which could be a Gray Wolf, red wolf, dog or coyote) intestinal wall. In dogs, symptoms include diarrhea, emaciation, anaemia, and, in severe cases, death. It has been known to kill coyotes and red wolves, but has not been reported to severely infect gray wolves, although it could pose a threat to them where it occurs in other canids. U. stenocaphala occurs in gray wolves, but its pathogenicity in them has not been studied.
The liver fluke, Metorchis conjunctus, is a trematode that infects the gall bladder and bile duct of a number of fish-eating mammals, as fluke larvae develop in the fish before they mature in a mammal. This parasite has been found in wolves in Alberta and Saskatchewan, and most of the cases involved wolves that were known to have been eating fish. Symptoms that were present in the infected wolves included swellings throughout the liver and dilated bile ducts. Two cases resulted in extensive damage to the pancreas. It is not known whether this parasite causes any mortality in wolves.
At least 21 different species of tapeworm have been known to infest wolves. Wolves usually contract tapeworm cysts from the prey animals they eat. Once the tapeworm cysts enter the wolf's body, they will attach themselves to the intestinal wall of the wolf and will feed off of the wolf's body fluids. The segments of the tapeworm (tapeworms are made up of a tiny, microscopic head and hundreds of body segments that are full of eggs) are usually expelled in the wolf's feces, and resemble tiny grains of rice. Symptoms of a severe tapeworm infestation include loss of appetite, weight loss, and mild diarrhea. Tapeworm infestations do not directly kill wolves, but a wolf suffering from a severe infestation may become weakened and unable to hunt effectively.
The two tapeworm genera that most often occur in wolves are Taenia and Echinococcus. Tapeworms are quite common in free ranging wolves, and it is thought that Echinococcus plays an important role in regulating wolf and moose populations. The mechanism goes as follows: As wolf density in an area increases, the sites that are being used extensively by the wolves will become contaminated by a large number of Echinococcus eggs. The presence of Echinococcus cysts present in moose populations using the areas frequented by wolves will then increase. Since the cysts usually occur within the pulmonary tissue of moose, animals with severe infections will become weak. Such moose will be more likely to be killed by wolves than healthy moose, so the presence of the parasite enhances the regulatory effect of wolf predation on moose.
Echinococcus Granulosus, EG for short and "Wolf Worms" by some is a parasite, a type of tapeworm. In Montana wolves examined there had literally thousands of these tiny tapeworms in their intestines. These tapeworms produce tens of thousands, maybe millions of microscopic eggs that are expelled in wolf feces. These eggs are viable for long periods of time, depending upon conditions. 63% of Montana wolves carry this disease, which is transmissible to humans. These millions of EG eggs can become airborne or get flushed by rain into moving water.
People who intake these eggs though inhalation or any sort of transport-to-mouth mechanism can develop cysts that may be discovered any time from soon after exposure to as long as 20 years later. Such a long incubation period causes EG to be a nightmarish, untrackable public health risk. When EG cysts form in a person, they are extremely difficult to detect. There are serological tests for presence of EG, but these tests have a spotty detection rate. Further, nearly all medical practitioners and diagnosticians are unaware of EG and are unlikely to look for or diagnose presence of EG cysts from non-specific patient complaints.
EG cysts have an affinity for human livers, lungs and brain, and sometimes heart. They may grow up to ten or 14 inches in diameter. Usually, there are multiple cysts in the affected organ. These cysts are an encapsulation of the larval form of EG, and one cyst may contain hundreds of these worm larvae. When a person develops EG cysts, that condition is called Hydatid Disease. If a diagnostician should luck onto the detection of any such cyst in a patient, the only way to address or remove the cyst is via surgery – cut it out. Because of the risks associated with such surgery, the physician will usually opt to let the cyst grow until it becomes life-threatening before attempting surgical removal. Meanwhile, more such cysts may form in the same or other organs of the patient.
A physician and pathologist who is a member of MSSA told me that he has seen a death from EG where the patient’s liver was destroyed by EG cysts. A scientific journal reports the potential for heart attacks because critical heart blood supply vessels are blocked by EG cysts. Imagine EG cysts in your brain and being forced to choose between the risks of letting them grow, or surgery to remove them. To summarize, 63% of Montana wolves are shedding millions of invisible, microscopic EG eggs across our landscape, eggs that can become airborne or water-borne and persist in the environment. These EG eggs can and do infect people. That is proven. Once infected, a person may develop cysts, up to 20 years later. The cysts will most likely be in the person’s liver, lungs, brain or heart. It is statistically unlikely that medical personnel will detect such cysts in a patient, except upon autopsy. If cysts are detected, the only solution is surgery, which is usually deferred because of the high risks of such surgery, until the risk of death from cysts exceeds the risk of death from surgery.
But, even that is not the whole story. There is another, similar type of tapeworm carried by wolves that is perhaps less studied and even more dangerous to humans. That is Echinococcus Multilocularis (EM for short). The life cycle, transmissibility and consequences of EM are similar to EG, but differ in some important ways. Since EM is even less studied than EG, we don’t know how prevalent EM may be in Montana. Further, when a person is infected with EM cysts, those cysts eventually rupture and the infected person dies suddenly from anaphylactic shock. The primary mechanism of death may or may not be detected upon autopsy, which, of course, no longer matters to the deceased. Because systematic EG and EM detection and reporting processes do not exist, we simply have no way at present to quantify the public health threat. In the face of this absence of information about EG and EM, FWP assures us that these diseases are no big deal. Instead of stressing that an ounce of prevention is worth a pound of cure, FWP, with its head firmly in the sand, assures us that there is no problem.
Research has been done both in Russia and abroad to try to explain the role of the wolf in the spread of invasive diseases caused by worms. In the Soviet Union alone the wolf can be infected with more than 50 types of parasites. Among these are several dangerous ones which can be transmitted to farm animals and to people. Significant damage can be done to wild hooved animals by larval parasites such as echinococcia, cysticercocci, and coenuri, all of which can attack man also. According to data from the Lenningrad Oblast' during a serious flare-up of cysticercosis not one observed female moose give birth to two calves, whereas in the Murmansk Oblast' where the outbreak was three times less severe all the moose females had two calves. The same type of situation was noted by Kheruvimov in 1969 in the Tambov Oblast'. There are also reports of the deaths of female moose and female deer caused by echinococcossi and cysticecocci. Wolves in the wild, seriously infected with the adult stage of cysticercosos by a tapeworm of the taenia family, are the sources of this parasitic invasion. It has been noted that where there aren't any wolves, the number of cysticerosis infected wild hooved animals is much less. According to our data those wolves seriously infected with tapeworms (the source of larval parasites in feral hooved animals and in man) are found where their main food supply is hooved animals. In the Nenets Autonomous Region all observed wolves were seriously infected with tapeworms and four out of five had widespread echinoccocci. In the Belovezhsk Forest from 1957 to 1962 all eight wolves who underwent autopsies were found to be infected with tapeworm types of parasites harmful to both animals and people.
Mange is cause by tiny mites that attach themselves to an animal's skin or fur. There are two main types of mange: sarcoptic and demodectic. In sarcoptic mange, the female mites will dig under the animals fur and lay eggs there, and the animal will become very itchy. Sarcoptic mange is probably the most significant ectoparasite of wolves, and is caused by the mite, Sarcoptes scabei. S. scabei is found throughout the world and can live on a variety of host species. In demodectic mange, the mites live in the pores on its host's skin and cause very little itching. Symptoms of mange include skin lesions, fur loss and crusting of the skin. The skin of animals with severe infections may become thickened and gray. Some animals with severe mange may also loose weight. Mange is spread when an animal carrying the parasites comes into direct contact with an uninfected animal, or when an uninfected animal rubs against a surface that an infected animal has directly contacted.
Mange is most likely an important regulating factor of wolf and coyote populations. Cases of mange in wolf populations increase when wolf densities increase, and the number of surviving pups in a wolf population decreases as the number of wolves with mange increases. Wolves with mange often freeze to death because of the hair loss that occurs with a severe infestation of mites.
Mange and parvovirus are known to be hammering wolf populations currently. In Yellowstone Park, the chief cause of wolf mortality now is wolves being killed by other wolves. Both of these are obvious signs of overpopulation. The wolf advocates will argue that because wolves are dying from overpopulation we must stop killing wolves, a pretty obvious comment on the quality of rationale used by wolf advocates. We know that rabies is endemic in other wild animals in Montana, especially in skunks and foxes. With wolves in the overpopulated condition demonstrated by wolf-wolf killing and existing diseases, it is only a matter of time before rabies begins to infect wolves, if it hasn’t already. Sarcoptic mange has been used in the past by wildlife "managers" to control wolf populations. In 1909, wolves that were caught and infected with sarcoptic mange were released into Montana, in hopes that the disease would spread to and infect and kill other wolves
The dog louse (Trichodectes canis) has been found in wolves throughout their North American range. It was most likely transmitted to wolves from dogs. Lice are transmitted when an infected individual comes into close or direct contact with an uninfected one. Wolves infested with lice may lose some of their guard hairs, and their underfur often becomes quite matted. Some wolves with severe infestations of lice may lose small patches of fur. Damage and and loss of hair is usually not the direct result of a louse infestation, but often occurs when the wolf attempts to remove the lice by biting or scratching. T. canis most likely does not significantly affect wolf populations, as adult wolves with lice are often noted to be in good condition.
Other ectoparasites that occur in gray wolves include fleas (Pulex simulans, Ctenocephalides canis), ticks (Amblyomma americanum, A. macuklatum, Dermacentor albipictus, D. variabilis, and Ixodes spp.) and the deer fly (Lipoptena cervi). These ectoparasites do not exert any control over wolf populations, and are less of a problem in northern regions than they are in warmer, southern regions.
Leptospirosis is a disease that is caused by bacteria from the genus Leptospira, which includes over 170 known species. This disease is transmitted when an uninfected animal comes into contact with the urine of an infected animal. The disease is very rare in free-ranging wolves.
Brucellosis is a disease caused by bacteria in the genus Brucella. This disease primarily affects ruminants and symptoms include orchitis, abortion or other reproductive problems. Wolves in northern Alberta, Siberia and the Canadian arctic have tested seropositive for the disease. In south-central Alaska, some of the wolves have been found to carry antibodies for the disease. The effects of brucellosis in wild wolves is largely unknown. Two pregnant wolves that were experimentally infected with Brucella gave birth to some dead cubs, although whether that was the result of the brucellosis infection or not could not be proven. However, the "scientists" who deliberately infected healthy pregnant wolves with the disease did prove themselves to be sadistic scumbags.
Lyme disease is caused by the bacterium Borrelia burgdorferi, and can affect dogs, horses and humans. The disease was first discovered in New England in 1975, and has since been reported in at least 43 states and eastern Canada. Infection typically results from bites from infected Ixodes dammini ticks (deer ticks). White-tailed deer are the major hosts for the mature ticks, while small rodents (usually white-footed mice or eastern chipmunks) are the hosts for the immature ticks. These hosts can become infected with B. burgdorferi, but never show symptoms of the disease. Wolves in Minnesota and Wisconsin have been found to be infected with the disease, but clinical Lyme disease has not yet been found in wild wolves. A wolf that was once experimentally infected with B.burgdrferi showed some symptoms of the disease, which suggests that wolves may be susceptible to it.
Blastomycosis is a disease caused by the fungus Blastomyces dermatitidis, and is not contagious. It is rare in wild wolves, but has occurred in wolf populations in Minnesota and Wisconsin. It can be fatal to wolves.
If you have a morbid fascination with the diseases, parasites, and infections that wolves suffer from, I refer you to Will N.Graves' book "Wolves in Russia" for more information. Graves is obsessed with this aspect of the wolf to convince everyone that the wolf should be eradicated. But never forget that humans are susceptible to more diseases, parasites, and infections than wolves. With Graves' logic, humans deserve to be eradicated. I nominate Will Graves for his well deserved eradication.