Disease Guide

Plague in Dogs & Cats: Symptoms, PCR Testing & Isolation Care [2025]

Yersinia pestis infection — a rare but serious zoonotic disease

Last updated: 2026/01/06
PetHealthMap Editorial Team
Sources: CDC, WOAH, AVMA, National Taiwan University Veterinary Hospital

When to See a Vet

Seek emergency care immediately

  • Persistent high fever with lethargy or unresponsiveness
  • Rapid breathing or visibly labored breathing
  • Sudden loss of mobility or brief collapse

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

  • Persistent vomiting with inability to maintain normal food intake
  • Increasing diarrhea frequency with noticeable decline in alertness
  • Significant short-term weight loss or sudden drop in appetite

01What symptoms indicate something is wrong?

Dogs and cats infected with plague typically show systemic illness and gastrointestinal or multi-organ symptoms. Early signs may be subtle but tend to worsen progressively.

  • Lethargy and noticeably reduced activity
  • Reduced appetite or complete refusal to eat
  • Repeated vomiting or changes in vomit appearance
  • Diarrhea or changes in stool consistency and frequency
  • Gradual weight loss or sudden noticeable drop in body weight
  • Persistent or intermittent fever (elevated body temperature)
  • If any of the above symptoms appear, schedule a veterinary appointment promptly

Seek emergency care immediately if you notice the following symptoms:

  • ⚠️ High fever that does not subside, with severe depression and unresponsiveness
  • ⚠️ Difficulty breathing or obvious respiratory distress
  • ⚠️ Sudden collapse or inability to stand

02How to assess your pet at home — observation tips and emergency criteria

Keeping a systematic record of symptoms at home helps your vet quickly understand the progression and narrow the diagnosis.

  • Note when lethargy began and how much it has worsened
  • Record daily food intake and any episodes of refusal to eat
  • Log the number of vomiting episodes, timing, and the appearance of vomit
  • Observe and record bowel movement frequency and any changes in stool character
  • Weigh your pet regularly using the same scale and track weight trends
  • If you can measure temperature, record daily readings and the time taken
  • If symptoms persist or worsen, arrange an appointment with an internal medicine or infectious disease specialist

03How will the vet make a diagnosis? Common diagnostic tests

At the clinic, the vet will start with a physical examination and follow up with laboratory tests to confirm the infection source and severity.

Physical examination

assessing mentation, dehydration status, and lymph node enlargement

Complete blood count and biochemistry panel

evaluating organ function and inflammatory response

PCR molecular testing

identifying potential bacterial or pathogen presence

Serology

assessing antibody response or prior exposure history

Bacterial culture (if needed)

confirming the causative organism and testing antibiotic sensitivity

Advanced imaging (X-ray, CT)

evaluating thoracic and abdominal changes or pulmonary involvement

Testing is recommended at a specialist hospital or laboratory equipped to perform PCR and culture

04How to treat and care for your pet after diagnosis? Medication, dietary adjustments and care guide

Treatment and follow-up will be adjusted based on test results. Follow your vet's isolation and environmental cleaning instructions to reduce transmission risk.

  • The vet will determine appropriate treatment and supportive care based on test results
  • Follow the vet's dietary and hydration instructions to maintain your pet's strength
  • Monitor and record changes in alertness, appetite, and elimination at home
  • The vet will schedule follow-up visits to monitor blood work and other test results
  • Referral to an infectious disease specialist or a specialist hospital with diagnostic capabilities may be arranged if needed
  • Follow isolation and environmental disinfection recommendations throughout the follow-up period to minimise exposure risk

05What to prepare before your vet visit? Key information to help your vet diagnose quickly

1
Prepare a timeline or notes recording when symptoms began and how they changed
2
List recent diet, water intake, and any changes in food or environment
3
Record the number of vomiting or diarrhea episodes and the specific times they occurred
4
Bring a list of all current medications and supplements
5
If you have recent weight or temperature records, bring them to share with the vet
6
If you have stool or vomit samples, store and bring them as directed by the clinic

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.

Frequently Asked Questions (FAQ)