Positive SNAP Tests for Ehrlichia & Anaplasma: 2025 Vet Insights by Dr Duncan Houston 🐶🦠

Hello, I’m Dr Duncan Houston, BVSc. Today we're delving into positive SNAP tests for Ehrlichia and Anaplasma—two of the most common tick‑borne infections in dogs. I’ll help you understand what a positive result means, its limitations, and the best next steps to keep your pet healthy.

🧬 What SNAP Tests Detect

SNAP® tests from IDEXX screen for antibodies that dogs make in response to Ehrlichia and Anaplasma bacteria. These are often completed in‑clinic within minutes. A positive result confirms your dog has been exposed—but does not prove active infection. It simply indicates that your dog’s immune system has encountered the organism.

🔍 Why Positive ≠ Infection

There are several reasons your dog’s SNAP test might be positive:

• Recent exposure or cleared infection: Your dog created antibodies but didn’t get sick.
• Carrier state: The bacteria may still be present, but your dog shows no symptoms and appears healthy.
• Active infection: The disease may be present and may or may not have caused clinical signs.

⚠️ False Negatives & False Positives

• False negative: May occur early in infection when antibodies haven’t developed yet.
• False positive: Rare, but could reflect past exposure rather than ongoing disease.

📊 Interpreting SNAP Results

Your vet will look at the full picture:

• Tiny antibody test (+ SNAP) + no symptoms → might just monitor.
• SNAP positive + signs (low platelets, anemia, joint pain) → likely active infection needing treatment.

🧫 Confirmatory Tests

To determine whether treatment is needed, your vet may recommend:

• CBC (complete blood count): Often shows low platelets or anemia in active disease.
• Quantitative testing: Such as PCR to detect bacterial DNA in blood, or immunofluorescence assays (IFA) to confirm species.

🛡️ Monitoring vs. Treatment

1. Asymptomatic dogs (healthy + SNAP+):

• May only require regular check‑ups and follow‑up blood tests.
• Not every SNAP+ dog needs antibiotics immediately.

2. Symptomatic dogs (positive SNAP + clinical signs):

• Treatable with doxycycline for 4 weeks or longer.
• Your vet will set follow‑up blood tests to evaluate recovery.

🕒 When to Schedule Testing

Consider a SNAP test if your dog has:

• Been in tick‑endemic areas
• Suddenly developed bruising, bleeding, fever, lethargy, or joint pain
• Poor platelet or red blood counts on routine bloodwork

✔️ Key Takeaways

• A **positive SNAP test means exposure**, not necessarily disease.
• Further testing and clinical signs determine need for treatment.
• Watch, treat if sick, and repeat blood tests as directed by your vet.

📱 Ask A Vet for Next Steps

Unsure what your dog’s test means or whether to treat? Use the Ask A Vet app to consult with our veterinarians anytime—get clarity on testing, treatment, and follow‑up tailored to your pet. 🩺📞