several deer sitting in texas lawn

Deer Diseases To Be Aware Of

In the realm of deer management, it's crucial to stay vigilant about deer diseases. Whether you're a professional providing deer control services or a homeowner, being well-informed is paramount. Recognizing the signs of illness in deer is essential. Sick individuals may exhibit different behaviors than healthy ones. Additionally, it's important to note that deer can harbor various diseases, some of which can be transmitted to humans, pets, or other animals. These diseases play a significant role in the transmission cycle of Lyme Disease and can introduce ticks into the surrounding landscape.

Here are a few examples of diseases that deer can carry:

Chronic Wasting Disease (CWD)

Among the diseases that deer can carry, Chronic Wasting Disease (CWD) stands out as a particularly concerning threat. CWD is a fatal neurological condition affecting deer, elk, moose, and other cervids. Originating in captive mule deer in Colorado during the late 1960s, it has since spread to wild deer populations across multiple US states. Also, it is found in Canadian provinces and other countries.

CWD is instigated by misfolded proteins known as prions, which wreak havoc on the brain and nervous system of infected animals. Shedding through saliva, urine, and feces, these prions can endure in the environment for extended periods, complicating efforts to control the disease's spread.

Wildlife managers face a formidable challenge in addressing CWD due to its potential impact on deer populations. With no known cure and a prolonged shedding period preceding symptoms, infected animals can unwittingly spread the disease to others, potentially leading to population declines. Moreover, CWD compromises the safety of deer meat, rendering it unfit for human consumption.

CWD Control

Efforts to control the spread of CWD include testing for the disease in deer populations and implementing regulations to prevent the movement of infected animals. Many states have also implemented management strategies.  Also, these include techniques such as culling infected animals in an attempt to control the disease.

In addition to its impact on wildlife, CWD also has economic and social implications. The presence of CWD can result in reduced hunting opportunities and decreased revenue for local communities. Furthermore, the loss of healthy deer populations can have ecological impacts, such as changes in plant communities and impacts on other wildlife species.

EHD (Epizootic Hemorrhagic Disease)

EHD (Epizootic Hemorrhagic Disease): EHD is caused by a virus and is primarily spread by the bites of certain types of biting flies. It can cause fever, loss of appetite, weight loss, stiffness, and death. 

Epizootic Hemorrhagic Disease (EHD) is a viral disease that affects wild and domestic ruminants. These include white-tailed deer, mule deer, elk, and pronghorns. The disease is transmitted by biting midges of the Culicoides species. These species are found throughout the United States and in many other parts of the world. EHD is not a threat to humans, but it can be devastating to deer populations.

Symptoms of EHD in deer can vary depending on the strain of the virus, the age of the deer, and the deer's immune status. Some infected deer may exhibit no symptoms at all. Others may develop a high fever, severe internal bleeding, and extensive tissue damage. Symptoms can appear within a few days of infection and can progress rapidly, leading to death within one to two weeks.

Effects of EHD

The effects of EHD on deer populations can be significant. In some areas, mortality rates can reach as high as 90 percent. This disease can also have a long-term impact on deer populations. Surviving deer may be weakened and more susceptible to other diseases and predators. EHD can also affect hunting and wildlife management programs, as well as the economies of communities that rely on hunting and outdoor recreation.

EHD Control

While there is currently no vaccine or treatment for EHD, control measures are limited. Nonetheless, some steps can be taken to reduce the risk of infection. These include reducing the number of midges by controlling vegetation and avoiding areas with high midge populations during peak activity times. Also, removing stagnant water sources where midges breed.

Moreover, in addition to reducing the risk of infection, wildlife managers can also help monitor and control EHD outbreaks. This involves reporting sick or dead deer to state wildlife agencies, practicing proper field dressing and disposal of carcasses. Avoiding moving deer carcasses from areas with confirmed EHD cases to other locations is also crutial.

In conclusion, overall, EHD poses a serious threat to deer populations and the ecosystems that depend on them. Understanding the disease and taking steps to reduce the risk of infection can help protect deer populations and preserve the important role they play in our natural world.

Lyme Disease

Deer play a role in the transmission of this disease, they can carry the ticks that carry the bacteria responsible for Lyme Disease. 

Lyme disease is a bacterial infection that is transmitted to humans through the bite of an infected tick. However, many people are not aware that deer also play a significant role in the spread of Lyme disease. In fact, deer are the primary host for adult black-legged ticks, which are the primary carriers of the Lyme disease bacteria.

Deer Ticks

Black-legged ticks, also known as deer ticks, are small parasites that feed on the blood of animals, including deer, mice, and humans. These ticks are typically found in wooded areas, particularly in regions with a high population of deer. When an infected tick bites a deer, the deer becomes a carrier of the Lyme disease bacteria.

Deer are particularly important in the life cycle of the black-legged tick. After feeding on the blood of an infected deer, the tick can lay up to 3,000 eggs, which will hatch into larvae. The larvae then feed on the blood of small mammals, such as mice, which can also be carriers of the Lyme disease bacteria. As the larvae develop into nymphs, they feed on larger mammals, including deer. If an infected nymph bites a human, the person can become infected with Lyme disease.

Deer populations have increased significantly in many areas over the past several decades, in part due to the eradication of natural predators like wolves and cougars. As a result, the risk of Lyme disease transmission has also increased. In fact, studies have shown that the risk of Lyme disease is highest in areas with a high population of deer.

Steps To Reduce Risk

There are several steps that can be taken to reduce the risk of Lyme disease transmission from deer. One approach is to reduce the deer population in areas with a high risk of tick-borne diseases. This can be accomplished through the use of controlled hunting programs, as well as by encouraging natural predators to return to the area.

Another approach is to implement measures to reduce tick populations. This can be accomplished through the use of pesticides, as well as through the promotion of landscaping practices that reduce tick habitats. Useful practices include removal of leaf litter and the planting of tick-repelling plants like lavender and rosemary.


Brucellosis is a bacterial disease that affects the reproductive organs of white-tailed deer and other animals, it can also affect livestock and humans.

Brucellosis is a bacterial infection that can affect both humans and animals. In deer, the disease is caused by the bacteria Brucella suis, which can cause a variety of symptoms, including reproductive failure, weigh

In wild deer populations, Brucella suis can have significant ecological impacts. The disease can cause reproductive failure in female deer, which can lead to reduced population growth rates and even population declines. Brucellosis can also have economic impacts, particularly in domestic deer populations. In infected herds, the disease can cause decreased fertility and milk production, as well as weight loss and chronic wasting.

Brucellosis Strategies

There are several strategies that can be used to control and prevent the spread of Brucella suis in deer populations. One approach is to implement surveillance programs to detect the presence of the disease in wild and domestic deer populations. This can involve testing animals for the presence of the bacteria, as well as monitoring population trends and reproductive success rates.

Another approach is to implement management strategies that reduce the risk of disease transmission. This can involve implementing measures to reduce contact between infected and uninfected animals, such as by separating infected animals from the rest of the herd. It can also involve implementing measures to reduce the risk of transmission through ticks, such as by implementing tick control measures.

In some cases, vaccination may also be used as a strategy to control the spread of Brucella suis in deer populations. Vaccination can help to reduce the prevalence of the disease and can also help to reduce the severity of symptoms in infected animals.

Brucellosis is an important disease in deer, as it can affect both wild and domestic populations and can have significant economic and ecological impacts.

Transmission of Brucellosis

Transmission of Brucella suis in deer can occur through a variety of routes, including contact with infected animals or their bodily fluids, ingestion of contaminated feed or water, and inhalation of contaminated dust particles. The bacteria can also be transmitted through the bite of infected ticks.


It's worth noting that human infection by these diseases is generally rare, but it is possible. The risk of infection is higher for people who have close contact with deer and their habitat, such as hunters and farmers. To protect yourself and your loved ones, it's important to take necessary precautions such as wearing protective gear, avoiding contact with deer feces, urine and hunting or handling deer from areas with known cases of CWD.

 It's also important to cook deer meat thoroughly, and to avoid consuming the meat of deer that appear to be sick. Additionally, it's important to take precautions to prevent tick bites such as using insect repellents, wearing protective clothing, and checking for ticks regularly.

Also, these diseases are specific to certain regions and not all of them will be present in every region. It's important to consult with local authorities, check with local state wildlife agencies or local health department to get more information on what diseases are present in your region.

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