Dog heartworm

Dog Heartworm

Dog heartworm, scientifically known as *Dirofilaria immitis*, is a parasitic worm that primarily infects dogs, but can also affect other animals such as cats, wolves, and foxes. This parasite is transmitted through the bite of an infected mosquito and can cause serious health issues, including heart failure and damage to other organs.

Life Cycle

The life cycle of the dog heartworm involves several stages:

1. Mosquito Stage: The life cycle begins when a mosquito bites an infected animal and ingests microfilariae, which are the larval stage of the heartworm.
2. Larval Development: Inside the mosquito, the microfilariae develop into infective larvae over a period of 10 to 14 days.
3. Transmission to Host: When the mosquito bites another animal, the infective larvae are transmitted through the mosquito's saliva into the host's bloodstream.
4. Maturation in Host: Once inside the host, the larvae migrate to the heart and lungs, where they mature into adult worms over the course of 6 to 7 months.
5. Reproduction: Adult heartworms can live for 5 to 7 years in dogs, and during this time, they reproduce and release microfilariae into the host's bloodstream, continuing the cycle.

Symptoms

Infected dogs may exhibit a range of symptoms, which can vary depending on the severity of the infection:

• Mild Infection: Coughing, fatigue, and reduced exercise tolerance.
• Moderate Infection: Persistent cough, difficulty breathing, and signs of heart failure.
• Severe Infection: Severe weight loss, fainting, and fluid accumulation in the abdomen.

Diagnosis

Diagnosis of heartworm disease in dogs typically involves:

• Blood Tests: Detecting the presence of heartworm antigens or microfilariae in the blood.
• Imaging: X-rays or ultrasound may be used to assess the extent of heart and lung damage.

Treatment

Treatment of heartworm disease can be complex and involves several steps:

• Stabilization: In severe cases, the dog may need to be stabilized with medications to manage heart failure or other complications.
• Adulticide Therapy: Medications such as melarsomine are used to kill adult heartworms.
• Microfilaricide Therapy: Additional medications may be used to eliminate microfilariae.
• Preventive Measures: After treatment, dogs should be placed on a heartworm preventive to avoid reinfection.

Prevention

Preventing heartworm disease is crucial and involves:

• Monthly Preventive Medications: Administering medications such as ivermectin, milbemycin, or selamectin to prevent heartworm infection.
• Regular Testing: Annual testing for heartworm infection to ensure early detection and treatment.

Also see

• Heartworm disease in cats
• Parasitic diseases in dogs
• Mosquito-borne diseases