Vector-borne disease testing changes at PHOL

To: Ottawa Physicians and Nurse Practitioners
Date: July 10, 2025
From: Dr. Monir Taha, Associate Medical Officer of Health
Subject: Vector-borne disease testing changes at PHOL

Dear Colleagues,

Public Health Ontario Laboratory (PHOL) has recently updated its testing protocols for vector-borne disease testing. Please see an overview of the changes below. All links provide information in English only.

New PHOL Algorithm: Anaplasma PCR Replacing Single Serology Test Requests

PHOL has replaced single serology testing requests with PCR testing as the preferred diagnostic method for acute anaplasmosis. Serology will remain available but only if both an acute (within 2 weeks of symptom onset) and a convalescent (between 2 to 12 weeks of symptom onset) serum sample are submitted. A detailed description of testing methods can be found at Anaplasma – PCR and Serology | Public Health Ontario.

Implementation of a New Vector-borne and Zoonotic Virus Testing Intake Form

PHOL has introduced a new intake form to replace both the Arbovirus (Non-Zika) Testing Intake Form and the Mandatory Intake Form for Zika Virus Testing. Submission of the Vector-borne and Zoonotic Virus Testing Intake Form is now mandatory along with the General Test Requisition when requesting specific vector-borne or zoonotic virus tests. Submissions without the appropriate intake form may be cancelled. The new form includes updated clinical and epidemiological fields, including information for zoonotic viruses that was not previously collected.

The new Vector-borne and Zoonotic Virus Testing Intake Form must be completed and submitted for the following viruses: