Heartworm disease is a serious condition that can affect dogs, and regular testing is crucial for prevention and early detection. It is generally recommended to test your dog for heartworms at least once a year, especially if your dog is at risk of exposure to mosquitoes, which are the primary vectors for heartworm transmission.

Here are some key points to consider:
1. **Annual Testing**: For most dogs, an annual heartworm test is sufficient, especially if they are on a year-round heartworm prevention regimen.
2. **New Dogs**: If you adopt a new dog or move to a new area, it’s a good idea to have them tested for heartworms before starting them on preventive medication, even if they were tested recently by the previous owner.
3. **High-Risk Areas**: In regions where heartworm is endemic, more frequent testing may be recommended, particularly if your dog has missed doses of heartworm prevention or has had any other risk factors.
4. **Symptoms of Heartworm**: If your dog shows signs of heartworm disease, such as coughing, lethargy, or difficulty breathing, consult your veterinarian immediately, regardless of their last test date.
5. **Veterinary Guidance**: Always follow your veterinarian's recommendations regarding heartworm testing and prevention, as they can provide tailored advice based on your dog's health and lifestyle.

In summary, annual testing, combined with consistent use of heartworm prevention, is the best strategy to keep your dog safe from heartworms.

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Topics covered in this question:

Dog Health Prevention Vet Care Heartworm Dog Owner Tips