Our hospital is open for entry! We are requiring masks to be worn in the building at all times. Thank you!

Starting June 22nd, our Wednesday hours will be: 8am – 12pm, 1pm – 6pm 

Call us: 708-383-3606 | Get Directions | After Hour Emergencies: 773-281-7110

Heartworm Awareness


April is the official Heartworm Awareness Month, but whenever the temperature is above freezing it is Heartworm Awareness Month. 

At long last the winter chill is starting to abate! But with the coming of warmer weather, comes greater concern for transmission of heartworm disease to our pets.

Although heartworm disease is a concern year round, April is Heartworm Awareness month. We have discussed heartworm disease before (Carlson blog – heartworm prevention),  but we wanted to once again draw attention to this very concerning, yet very preventable disease.

How do our pets become infected with heartworm disease?

Heartworm disease is transmitted by mosquitoes.

Adult female heartworms living in an infected dog, fox, coyote, or wolf produce microscopic baby worms called microfilaria that circulate in the bloodstream. When a mosquito bites and takes a blood meal from an infected animal, it picks up these baby worms, which develop and mature into “infective stage” larvae over a period of 10 to 14 days.

When the infected mosquito bites another dog, cat, or susceptible wild animal, the infective larvae are deposited onto the surface of the animal’s skin and enter the new host through the mosquito’s bite wound. Once inside a new host, it takes approximately 6 months for the larvae to mature into adult worms that live in the heart. Once mature, heartworms can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet. – (American Heartworm Society   https://www.heartwormsociety.org/pet-owner-resources/heartworm-basics )

How can you prevent Heartworm disease?

Heartworm disease is easily prevented by giving one Heartgaurd tablet once monthly, year round. (This also prevents/treats some intestinal parasites).

The American Heartworm Society advises annual blood testing for heartworm disease followed by continual monthly heartworm prevention. 

Why should you purchase your medication through us?

If your pet should develop heartworm disease while taking preventive purchased at our hospital, Boehringer Ingelheim, our medical supplier, will cover all costs for the treatment for heartworm disease. Treatment includes injections, oral medication, and sometimes hospitalization. Treatment cost can range from $400 to over $1,500 depending on size of your pet and severity.

You will have the assurance that your product has been stored appropriately and is authentic.

Why do you need to treat your dog for 12 months?

The American Heartworm Society recommends protection every month regardless of where you live. Owners are mobile and travel with pets to warmer climates thus increasing the chance of infection. 

Although mosquitoes shut down at temperatures below 50 degrees, based on the calendar to your right you can see that we consistently have temperatures allowing for mosquitoes to be present in the Chicago area every month November – February.

Why is heartworm becoming more prevalent?

We are treating more cases of heartworm disease in Oak Park because many pet owners are not treating their pets with preventative year round or not at all. Our shelters are housing animals coming from warmer climate states where natural disasters have occurred. These states have a higher prevalence of heartworm disease. When these heartworm positive animals are brought to the Chicago area, the risk of transmission to our local pet population increases. This has greatly impacted the number of cases we are seeing in our area.

It is our pleasure to serve you and your pets. Please do not hesitate to call our offices (708-383-3606) if you have any questions or concerns. Thank you for allowing us to be a part of your veterinary healthcare team.


Contact Us

Carlson Animal Hospital


414 Lake St. Oak Park, IL 60302

Clinic Hours

Monday-Tuesday: 8 AM-12 PM, 1-6 PM Wednesday: 8 AM-12 PM, 1 PM-4:30 PM, 6-8 PM Thursday-Friday: 8 AM-12 PM, 1-5 PM Saturday: 8 AM-1 PM Sunday: Closed