Certain US states saw elevated rates of parasite-borne illnesses in cats and dogs last year, according to 2024 data from the Companion Animal Parasite Council, a nonprofit organization focused on bringing awareness to the risks posed by parasites. Although parasite-related illness rates in dogs and cats varied by state, these organisms affect all states, including during the winter months.

"Parasites don't follow a calendar," Kelly Cairns, DVM, MS, DACVIM (SAIM), vice president of medical excellence and education at Thrive Pet Healthcare, said in a news release.

 "We see dogs and cats dealing with parasite-related illnesses throughout the year, even if they don't go outside much. Sometimes, it just takes one little mosquito slipping in through an open door or a flea hitching a ride on someone's pant leg for your furry friend to end up with more than just an itch."

Last year, 1 in 15 dogs tested positive for heartworm disease in Mississippi, making this the state with the highest infection rate. Louisiana, Alabama, and Arkansas followed closely behind, each with a rate of 1 in 30 dogs testing positive. According to Thrive, cases of heartworm have risen in Texas, South Carolina, and Georgia.

Mosquitoes are vectors for heartworm, which affects a dog or cat’s heart and lungs. Symptoms of heartworm in dogs include coughing, shortness of breath, fatigue following moderate activity, or weight loss. Still, some canines may not exhibit any signs until the disease has progressed.

Although less common, cats are also at risk of contracting heartworm, with infection being possible through a single mosquito bite. In the US, approximately 1 in 500 cats test positive for heartworms annually.

 In 2024, Texas, Mississippi, Alabama, and Louisiana showed higher rates of heartworm in cats, with 1 in 200 of these animals testing positive for the parasite.

Cats that have been infected with heartworm may exhibit nonspecific symptoms that can resemble other feline diseases. Symptoms include vomiting, coughing, difficulty breathing, decreased activity and appetite, and weight loss.

Like dogs, some cats may be asymptomatic, with some being able to naturally eliminate the heartworms, while others may die suddenly without ever showing signs of illness.

 According to the FDA, felines with heartworm disease seldom show signs of heart failure

Last year, West Virginia reported the highest infection rate in the US for Lyme disease, where 1 in 6 dogs tested positive. Other states at high-risk for the disease include Vermont, Maine, and Connecticut, with 1 in 8 dogs testing positive. Trailing closely were Pennsylvania, Massachusetts, and New Hampshire, with 1 in 10 dogs showing positive Lyme disease results.

In dogs, Lyme disease is the most prevalent tick-borne disease. Symptoms include joint stiffness, lethargy, and loss of appetite.

With 1 in 3 dogs testing positive for anaplasmosis, Maine and Vermont had the highest rates of the disease in the nation. Following these 2 states were Connecticut, New Hampshire, and Massachusetts, with 25% of dogs showing positive results.

Affecting dogs, cats, and humans, the disease is spread by ticks. Symptoms of anaplasmosis in cats and dogs include fever, lethargy, joint pain, and loss of appetite. In humans, symptoms mimic those of the flu.

Ehrlichiosis is another tick-borne illness, with the disease being poorly understood.

 In cats, ehrlichiosis affects their blood cells. 

, the bacteria that cause the disease, can be transmitted to cats within 3 hours of when the tick attaches itself. Infected cats can experience a range of varying symptoms, including

Enlarged spleen, causing an enlarged appearance of the abdomen

One in 6 dogs tested positive for ehrlichiosis in Arkansas, making it the state with the highest number of cases. Missouri and Oklahoma followed, with 1 in 10 dogs and 1 in 11 dogs, respectively, having the disease.

Canines with ehrlichiosis will undergo 3 stages of the disease: acute, sub-clinical, and clinical or chronic.

In the acute stage, dogs may experience fever, swollen lymph nodes, respiratory distress, weight loss, bleeding disorders, and neurological disturbances. Patients who progress to the sub-clinical phase show no clinical signs. Following the sub-clinical phase, untreated dogs will advance to clinical ehrlichiosis, during which they are likely to develop issues like anemia, bleeding episodes, lameness, eye problems, neurological problems, and swollen limbs.

With approximately 1 in 4 cats and 1 in 7 dogs being affected by fleas, officials with Thrive expressed the importance of year-round prevention in a recent news release. “A tick can survive for more than 200 days without food or water, and fleas can continue to multiply even in your living room," Cairns said.

 "That's why year-round prevention makes a big difference."

Parasite hot zones: States where pets are most at risk. News release. Thrive Pet Healthcare. April 2, 2025. Accessed April 3, 2025. 

https://prnmedia.prnewswire.com/news-releases/parasite-hot-zones-states-where-pets-are-most-at-risk-302418633.html

Keep the worms out of your pet’s heart! The facts about heartworm disease. December 22, 2022. Accessed April 3, 2025. 

https://www.fda.gov/animal-veterinary/animal-health-literacy/keep-worms-out-your-pets-heart-facts-about-heartworm-disease#:~:text=Cats%20with%20heartworm%20disease%20may,show%20signs%20of%20heart%20failure

Jones L. Ehrlichiosis in cats. PetMD. May 25, 2022. Accessed April 3, 2025. 

https://www.petmd.com/cat/conditions/infectious-parasitic/ehrlichiosis-cats

Williams K, Llera R, Ward E. Ehrlichiosis in dogs. VCA Animal Hospitals. Accessed April 3, 2025. 

https://vcahospitals.com/know-your-pet/ehrlichiosis-in-dogs

Articles

Data on US states with the highest infection rates for heartworm, Lyme disease, anaplasmosis, and ehrlichiosis is presented.

States with the highest cases of parasite-borne diseases in cats and dogs

Welcome to The Decade of the Cat. The emotional bond between humans and their feline companions has gained significant recognition in recent years, reflecting a deeper understanding of this relationship's profound impact on both species. As cultural attitudes shift and caregiving priorities evolve, more caregivers seek veterinary support for their cat’s emotional and behavioral health. This presents a meaningful opportunity for veterinary teams to lead, innovate, and elevate feline patient outcomes. Emotional well-being is no longer a fringe topic, it has become a central focus for cat owners and veterinary professionals alike.

Cats have journeyed from revered companions in ancient civilizations to their status as cherished family members in modern households. Historically, widespread misconceptions portrayed cats as aloof and independent, with emotional needs often overlooked. However, recent studies reveal their intricate emotional lives and cognitive abilities, challenging the notion that they are merely solitary animals. Misunderstandings about their behavior and innate expertise in masking signs of illness have long challenged our ability as veterinary professionals to provide optimal care. Yet today, the science is clear: cats are emotionally complex, cognitively advanced, and socially nuanced.

Research has shown cats can form secure attachments to their owners, like infants with caregivers and they recognize human emotions, read tone and gesture, and exhibit behaviors linked to empathy and social awareness.

 For veterinarians, this knowledge isn’t just interesting; it’s clinical. It shapes how feline behavior is interpreted in the exam room, manage stress in hospitalized patients, and guide caregivers through decisions impacting quality of life.

The mutual benefit: Why emotions matter in medicine

Understanding the reciprocal emotional bond between cats and their people opens new pathways for preventive care and client communication. Research shows that pet ownership, especially for cats, can reduce anxiety and stress, improve cardiovascular health, and build emotional resilience.³ Conversely, a caregiver’s mental health and emotional stress can directly influence a cat’s behavior, stress levels, and overall welfare. This interplay gives veterinary professionals a clear role: we’re not only treating animals but also guiding caregivers, helping them interpret signs of stress, pain, behavior change, or environmental mismatch that may impact their cat’s health. Insights from organizations like FelineVMA, International Cat Care, Human Animal Bond Research Institute, and the Waltham SHINE study confirm what many caregivers and clinicians have long suspected: cats experience a wide range of emotions and possess the cognitive capacity to form social bonds and navigate complex environments.⁴

Today’s cat caregivers are more informed, invested, and increasingly prioritizing their cats' emotional well-being and physical health. They seek relationships with veterinary teams who understand their feline companions' emotional and behavioral needs and offer species-specific, proactive guidance. This evolving mindset reshapes veterinary practices, drives product innovation, and influences market dynamics. For veterinarians, this isn’t just a cultural shift; it’s a call to deliver more personalized, feline-focused care that integrates emotional well-being into everyday protocols and addresses the full spectrum of each cat’s needs.

Innovation strengthens the human-feline bond

As caregivers become more emotionally invested in their cats’ overall well-being, new tools are emerging to support a more proactive, informed approach to feline health. Moggie, a cat-only health and behavior tracker, is designed to help caregivers effortlessly understand how their cats are doing physically and emotionally. By continuously monitoring daily activity in the home environment, tools like this offer valuable insights that support early intervention, behavioral awareness, and peace of mind across all life stages. Unlike the limited snapshot provided during a clinic visit, where stress, unfamiliar environments, and masking behaviors often alter a cat’s responses, real-time data from the home offers a clearer, more accurate picture of a cat’s true behavior and well-being. In a world where emotional wellness is increasingly prioritized, tools like Moggie strengthen the bond between cats and their people while helping to elevate the standard of care.

The future of feline care will be defined not only by medical advances but also by how well we understand and support the emotional lives of cats and their people. Continued innovation and research, especially through collaboration between veterinary professionals, pet brands, and tech startups, will be essential in shaping this next chapter. Moggie exemplifies this evolution, showing how technology can deepen our connection to cats while enhancing their quality of life.

Today’s veterinary care teams have access to tools that can dramatically transform care. By prioritizing emotional well-being alongside physical health and embracing solutions extending our reach beyond the exam room, we can build stronger, more meaningful relationships between cats, caregivers, and clinicians. The opportunity is ours: to lead with empathy, innovate with intention, and ensure that every cat receives care that honors the full depth of who they are.

Vitale KR, Behnke AC, Udell MAR. Attachment Bonds between Domestic Cats and Humans. 

. 2019;29(18):R864-R865. doi:https://doi.org/10.1016/j.cub.2019.08.036

Quaranta A, d'Ingeo S, Amoruso R, Siniscalchi M. Emotion Recognition in Cats. 

. 2020;10(7):1107. Published 2020 Jun 28. doi:10.3390/ani10071107

HABRI Benchmark Survey of Pet Owners. Human Animal Bond Research Institute. News release. Accessed April 3, 2025.

Heath S. Understanding feline emotions: … and their role in problem behaviours. 

. 2018;20(5):437-444. doi:https://doi.org/10.1177/1098612x18771205

Elevating the human-cat connection in veterinary care

Deepening the human-feline bond

The American Veterinary Medical Association (AVMA), after working with congressional offices and other advocacy work, worked to lead the reintroduction of the Rural Veterinary Workforce Act in the Senate and House. The legislation, reintroduced by Senators Mike Crapo (R-Idaho) and Tina Smith (D-Minn.) and Representatives Adrian Smith (R-Neb.) and John Larson (D-Conn.), would help underserved and rural areas recruit and retain veterinarians.

"Recruiting and retaining veterinarians through the Rural Veterinary Workforce Act is key to protecting our nation’s food supply, preserving animal welfare, and upholding public health," said Sandra Faeh, DVM, AVMA president, in an organizational release.

 "Livestock and public health veterinarians are essential to strengthening the nation’s animal health infrastructure and agricultural economy. We urge Congress to address this increasingly important issue by passing the Rural Veterinary Workforce Act."

According to the release, the legislation, which is strongly endorsed by the AVMA, would

Align tax code with human and other healthcare professions’ award funds.

Expand the reach and maximize the allocated funding of the Veterinary Medicine Loan Repayment Program (VMLRP). This will help attract veterinarians in US Department of Agriculture-designated veterinary shortage areas by assisting with student debt.

End federal taxation on VMLRP awards, giving more veterinarians the chance to participate in a program that offers up to $120,000 over 3 years for student loan repayment in exchange for service in one of the designated shortage areas.

"Veterinarians are vital to the work of America's farmers and ranchers and the integrity of our food supply chain. Yet many areas of the country suffer from lack of access to their services," said Rep.Smith.

 "This bipartisan bill would make commonsense tax relief available to veterinarians who choose to live and work in the communities which need their help to care for their livestock and protect the agriculture industry from pests and disease. I thank my colleagues for joining me in reintroducing it."

The USDA declared 243 rural veterinary shortage areas in 46 states in 2025, making it the highest number of shortage areas ever, compared to 237 rural veterinary shortage areas in 47 states the USDA declared in 2023.

 The USDA has awarded 883 veterinarians with the VMLRP since 20210, with 2,197 applications received to participate in the program since it was created.

"In nearly every state in the country, there are shortages for veterinarians, especially in rural areas," expressed Sen. Smith.

 “This record shortage causes serious harm to the health of animals and the public. Providing additional funding to the Veterinary Medicine Loan Repayment Program and updating the tax code to better serve veterinarians will allow more qualified vets to do vital work with our animals in underserved communities."

AVMA echoes Congress’ renewed call to recruit and retain veterinarians in high-need areas. News release. American Veterinary Medical Association. March 27, 2025. Accessed April 3, 2025. 

https://www.avma.org/news/press-releases/avma-echoes-congress-renewed-call-recruit-and-retain-veterinarians-high-need

AVMA reignites congressional efforts to address highest level of rural veterinary shortages. News release. American Veterinary Medical Association. September 19, 2023. Accessed April 3, 2025. 

https://www.avma.org/news/press-releases/avma-reignites-congressional-efforts-address-highest-level-rural-veterinary

The Rural Veterinary Workforce Act would help retain and recruit veterinarians in rural or underserved areas

Congress renews call to recruit and retain veterinarians in areas of need

Clostridial myositis, also known as gas gangrene, malignant edema, or clostridial myonecrosis, is an infection of skeletal muscle by any of several 

species. Pathogenic bacteria within the genus 

are anaerobic, gram-positive rods that can produce spores that are resistant to various environmental and chemical factors.

The key component for clostridial myositis to occur is the creation of a local anaerobic environment within the skeletal muscle, which can occur with tissue injury, along with the presence of spores or bacteria. There is still debate whether these spores may be introduced at the time of injury or reside within the skeletal muscle prior to injury, and both sources may be valid.

 Clostridial myositis is reported to occur most frequently secondary to intramuscular injection, particularly of flunixin meglumine; however, it can also occur because of wound contamination, perivascular injection, castration, foaling injuries, or omphalophlebitis.

 Rare cases have no history of open injury, and in these cases, previous seeding of the muscle with spores followed by blunt trauma is suspected.

Once the clostridial spores or bacteria have the correct environment for spore germination and bacterial proliferation, toxin production results in severe tissue necrosis, along with systemic toxemia and bacteremia. Malignant edema is when cellulitis is present without myositis, but it may progress to involve the skeletal musculature.

Clinical signs of clostridial myositis are typically seen within 6 to 72 hours of injury or injection.

 Systemic toxemia may develop very quickly after the onset of clinical signs, and animals may be found dead.

 Initial clinical signs include fever, severe lethargy, tachycardia, reluctance to move, and anorexia. The affected site becomes swollen and painful and develops crepitus and subcutaneous edema.

 Horses may become recumbent because of systemic toxemia and severe pain.

A presumptive diagnosis of clostridial myositis is often made based on clinical signs and history. Aspiration of the swollen, edematous areas reveals serosanguinous, malodorous fluid with or without gas. Gram stain of the aspirated fluid often reveals gram-positive, spore-forming rods.

 Exudate and/or affected muscle tissue can be submitted for fluorescent antibody testing, immunohistochemistry, anaerobic culture, and/ or polymerase chain reaction for confirmation and species distinction, which may affect prognosis.

 Clinicopathologic abnormalities are nonspecific and consistent with a septic process, and elevated muscle enzymes may be noted but often do not correlate with the degree of myonecrosis.

 Ultrasound and/or radiographs of the area will show areas of subcutaneous edema and gas under the skin (

Images courtesy of Erica Secor, DVM, MS, DACVS-LA

Rapid diagnosis and aggressive treatment are pivotal for the survival of horses with clostridial myositis and, even with appropriate therapy, may be unsuccessful. Surgical fenestration of the skin and fascia, along with debridement of infected muscle tissue, appears crucial to a successful outcome, both through the removal of bacteria and disruption of the anaerobic environment, which lead to bacterial proliferation and toxin production (

Figure 2A, Figure 2B, Figure 2C, Figure 2D, Figure 2E and Figure 2F

Typically, the skin overlying these areas will necrose and slough, resulting in large wounds requiring long-term therapy. Wound therapy is crucial following fasciotomy and should include continued debridement of infected tissue, hydrotherapy, topical wound care, and additional fasciotomy if needed.

Antimicrobial therapy includes high-dose potassium penicillin (44,000 IU/kg intravenously every 6-8 hours) with or without the addition of metronidazole.

 Susceptibility suggests that tetracyclines and chloramphenicol should be effective and may be considered for oral medication options following the discontinuation of intravenous antimicrobials.

 Antimicrobial medications should be continued for a minimum of 7 days following infection resolution.

Hyperbaric oxygen therapy is often used in humans with gas gangrene and may improve survival when used in conjunction with surgical debridement; however, this is not common equipment in most equine hospital facilities.

 Additional supportive measures may include intravenous fluid therapy, management of anorexia through intravenous or oral routes, and pain management. Additional complications can arise because the primary disease process includes hemolytic anemia

Complications secondary to systemic toxemia may include disseminated intravascular coagulation, multiorgan failure, and laminitis. Airway management by tracheostomy may be necessary in cases where the neck or head is involved because of severe swelling and edema.

Prognosis is guarded for cases of clostridial myositis, with reported survival rates of 31% to 73%.

 Rapid intervention, including fasciotomy, appears key in improving survival rates, with a nearly 40% improvement in survival in horses undergoing fasciotomy in the first 24 hours of hospitalization compared with those with delayed surgical intervention.

infections showing the greatest survival, whereas those with 

or mixed infections show lower survival rates.

 It is important to remember that therapy must be initiated before identifying 

Educating owners on the risks of intramuscular injections, particularly of flunixin meglumine, may help reduce the chance of clostridial myositis. These cases are best managed in a hospital setting, and successful treatment requires the owner’s dedication in time and finances. Although this disease is a rare outcome of skeletal muscle trauma, early recognition and therapy are essential for a successful outcome and, even then, can be difficult to attain.

MacLeay J. Diseases of the musculoskeletal system. In: Reed SM, Bayly WM, Sellon DC. 

Peek SF, Semrad SD, Perkins GA. Clostridial myonecrosis in horses (37 cases 1985-2000). 

. 2003;35(1):86-92. doi:10.2746/042516403775467513

Ortega J, Daft B, Assis RA, et al. Infection of internal umbilical remnant in foals by Clostridium sordellii. 

. 2007;44(3):269-275. doi:10.1354/vp.44-3-269

Uzal FA, Navarro MA, Asin J, Henderson EE. Clostridial diseases of horses: a review. 

. 2022;10(2):318. doi:10.3390/vaccines10020318

Wang C, Schwaitzberg S, Berliner E, Zarin DA, Lau J. Hyperbaric oxygen for treating wounds: a systematic review of the literature. 

. 2003;138(3):272-280. doi:10.1001/ archsurg.138.3.272

Jeanes LV, Magdesian KG, Madigan JE, Meagher D. Clostridial myonecrosis in horses. Comp Cont 

. 2001;23:577-587. http://assets.prod.vetlearn.com.s3.amazonaws.com/mmah/f2/68cc5be7ac420399a2bfe1244bbfe4/ filePV_23_06_577.pdf

This skeletal muscle infection is best managed in a hospital

Clostridial myositis in horses

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, discusses diagnostic techniques for dermatophytes

Diagnostic tests for identifying dermatophytes

, Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, offers an overview of the various diagnostic tests available for dermatophytosis—a common fungal infection in cats and dogs. In the video, Santoro discusses some pros and cons of each test, and explains what the best diagnostic technique is.

Below is a partial transcript, lightly edited for clarity:

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM: 

One of the common fungal infections is dermatophytosis, and with dermatophytes, there are different type of tests that we can do. The simplest test is called Wood lamp, which is a very sensitive test but not very specific, followed by hair plucking and trichography.

So trichography essentially implies that the veterinarian will take [a] hair sample, look at the microscope, and look for alterations of the hair shaft. This test is very specific, but contrary of the wood lamp, it’s not really sensitive because it depends [on whether] we collect the affected hair or not.

Then there is a dermoscopy, which is a new technique, relatively new, in which we use a magnified lens, essentially, to magnify the visualization of the skin and you can see specific alterations of the hair associated with dermatophytosis.

And again, as I said earlier, the best diagnostic methodology is a fungal culture. So a fungal culture [involves] the collection of hair, specifically the periphery of the lesion, and putting this hair or scales—or whatever material we have—in a culture medium and submitting it to the microbiology laboratory. This test is the best in terms of specificity and sensitivity, but also requires up to 3 weeks to kind of specifically isolate the organism.

Once the organism has grown and is present in the culture, the culture has to be followed by a microscopic identification of the organism. So the microbiologist will specifically look at what type of morphology the organism has, to identify the genus of the species of the fungus.

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, discusses diagnostic techniques for dermatophytosis

Shannon Bass, DVM, president of the North Carolina Veterinary Medical Association,and host Adam Christman, DVM, MBA,  to discuss the NCVMA's role in helping those impacted by disasters.

The Vet Blast Podcast presented by dvm360: Are you prepared for a disaster?

On this week's episode of The Vet Blast Podcast presented by dvm360, Adam Christman, DVM, MBA, welcomed Shannon Bass, DVM, president of the North Carolina Veterinary Medical Association to discuss preparedness and ways to help if you are in or near an area that was impacted by some type of disaster. Throughout the episode, Bass shared with Christman why professionals should not just self-deploy, where to access grants, and how much NCVMA has been able to give back to its veterinary community. 

The communities like to get involved too. So not just, I'm assuming, not just the veterinary professionals too, but pet owners and alike, they really want to get involved. So it sounds like it's a collaborative approach to disaster preparedness.

It really is, and we saw so many examples of a shelter might say, I need cat litter. And so pretty quickly, what we saw within a few days, they'd get cat litter, but then someone would find that social media post a week later and start to propagate it again. And then the shelter would get the second and third and fourth wave of cat litter that they didn't meet at that time, and they had no place to store it at that time.

So it was really tricky when you saw kind of this glut of supplies. And then on the non veterinary side, when I was there, a few times, you would drive by churches that had just tables of soaking wet clothes in their parking lot, because so many random clothes had been donated with no real destination that they were just going to get thrown in the trash.

It's unbelievable. And I know the AVMA has some resources through their website as well, right?

They have some great resources. And the AVMF, the American Veterinary Medical Foundation, they donated to the NCVMA. They were great partners. They have wonderful grants as well. And so any AVMA member, and I do think they even have a set of grants for non members. And so the AVMA is has been a really great partner for us. We were able to establish 2 different grants that were new just for this disaster, one [was] veterinary community grants, and those were $300 grants that were available to any veterinary staff member. All they had to do was prove to us that they were employed at a veterinary hospital on the day of the storm. They didn't have to have receipts. It didn't have to be for any specific expense. It was a community grant for those individuals, and that has felt really good. It's not a ton of money, but it's something to to help folks in that area

Podcasts

NCVMA president Shannon Bass, DVM, shares how veterinary teams can help and be more prepared for a natural disaster