How do dogs and cats usually become infected with Hepatozoonosis?

Dogs and cats are commonly infected by ingesting intermediate hosts carrying the pathogen, such as raw or undercooked fish. Prevention includes avoiding raw food and discussing regular screening and isolation measures with your vet.

What tests are needed to confirm infection?

Common diagnostics include liver function blood panels, PCR nucleic acid testing, abdominal imaging (X-ray or ultrasound), and in some cases a liver biopsy — the exact tests are chosen based on your vet's assessment.

How soon can improvement be expected after starting treatment?

This varies with severity. Mild cases may show improvement within a few weeks, while complex cases involving liver damage can take several weeks to months. Regular follow-up visits are essential to monitor treatment response.

How can I reduce the risk of infection in daily life?

Avoid feeding raw or undercooked fish, minimize contact with wild intermediate hosts, and schedule regular health check-ups. Discuss preventive strategies with your vet.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Hepatozoonosis in Dogs & Cats: Symptoms, PCR Testing & Home Care [2025]

Hepatozoonosis is a tick-borne protozoal infection more commonly seen in dogs than cats. Signs include fever, weight loss, and muscle pain. While complete elimination is difficult, the condition can be effectively managed with long-term medication.

Take 1 minute to check the symptoms first

Last updated: 2026/01/05

Pethealthmap Editorial Team

Sources: WSAVA, Taiwan Society of Veterinary Internal Medicine, National Taiwan University Veterinary Hospital

When to See a Vet

Seek immediate veterinary care (emergency)

•Severe lethargy, unable to be roused or respond
•Persistent vomiting or complete refusal to eat for more than a day
•Eye/mouth membranes or the whites of the eyes turning noticeably yellow with no appetite

Schedule a veterinary visit soon (within 24–72 hours)

•Continued weight loss over more than a week with no clear improvement in eating
•Marked increase or decrease in water intake and urination
•Unsteady walking or intermittent lameness

01What Signs Indicate Something Is Wrong?

Common signs of Hepatozoon infection in dogs and cats, and what to watch for before your vet visit.

Gradual weight loss or noticeably reduced appetite
Changes in urination frequency or significantly abnormal urine output
Noticeably increased frequency or volume of water intake
Intermittent fever or persistently abnormal body temperature
Unsteady gait, limb weakness, or lameness
Discharge around the eyes, mouth, or nose; yellowing of mucous membranes or sclera (icterus)
If any of these signs appear, arrange a veterinary assessment as soon as possible

02How to Monitor at Home: Key Observations and When to Seek Emergency Care

Key observations to record at home before your visit — these help your vet make a faster, more accurate assessment.

Weigh your pet at the same time each day and record the results
Track daily urination frequency and any changes in urine volume
Measure and record total water intake each day
Take your pet's temperature at home and note the time and reading
Record short videos of your pet walking and moving, with timestamps
Note when changes in energy level or appetite first began
If symptoms persist or worsen, seek veterinary care promptly

03How Will the Vet Diagnose This? Common Diagnostic Tests

An overview of the diagnostic tests your vet may recommend and what each one is looking for.

Physical examination

palpation to assess pain and hepatomegaly

Blood work

assessing liver function, complete blood count, and inflammatory markers

Radiography

providing baseline abdominal imaging to rule out other causes

PCR testing

detecting pathogen nucleic acids to confirm infection

Tissue biopsy

evaluating microscopic pathological changes in the liver

CT scan

used for complex cases or pre-surgical evaluation

Seek a clinic equipped to perform PCR and imaging diagnostics

04Post-Diagnosis Treatment & Care: Medication, Diet Adjustments & Home Management

A summary of treatment principles, home care, and the importance of regular monitoring.

Develop a medication or supportive care plan based on diagnostic results
Adjust to a prescription diet and monitor food intake and digestive response
Monitor weight, water intake, and urination changes at home
Schedule regular follow-up visits as directed for blood work or imaging
If response to treatment is poor or the case is complex, consider referral to a specialist
Confirm follow-up test schedule and prognosis timeline with your vet

05What to Prepare Before Your Appointment: Helping Your Vet Identify the Cause Quickly

Write down the date symptoms started and how they have progressed

Bring water intake and urination records from the past week

Provide a list of current medications and supplements

Bring any previous imaging or lab reports if available

Prepare symptom videos and a written list of specific questions to ask

Call ahead to book at a clinic that can perform PCR or related diagnostic tests

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.