Mpox Clinician Update

Alert Date

The Windsor-Essex County Health Unit is sharing important updates from the Office of the Ontario Chief Medical Officer of Health about mpox (March 10, 2023).

General Information

Consistent with the World Health Organization’s November 28, 2022, announcement, Public Health Ontario will now refer to human monkeypox disease as mpox. There have been eight new cases of mpox in Ontario since January 2023, and cases continue to occur globally. Mild and subclinical infections are suspected to be the cause of ongoing transmission.

Clinical Presentation and Testing

Mpox has a broad range of clinical presentations. Common symptoms include fever, new rash/lesions in the mouth, genital, and/or peri-anal region, rectal pain, and lymphadenopathy. Emerging evidence suggests that the clinical presentation of mpox in vaccinated individuals may be more mild or subclinical. It is therefore recommended that clinicians keep mpox on their differential diagnosis and to use a lower threshold to test at-risk groups with compatible signs/symptoms. Specimens should be taken from skin lesions in patients with a rash and rectal swab for those with rectal pain/lesions. Nasopharyngeal (NP) swabs can be used when a patient does not have a rash but present with other compatible signs and symptoms. When conducting mpox testing, testing for other STIs including syphilis, HSV, and VZV must also be considered.

Individuals at Risk

Mpox has mainly, but not exclusively, affected gay, bisexual, men who have sex with men, men who have more than one, new, and/or anonymous sexual partners.


The provincial guidance recommends self-isolation for all suspected and confirmed cases of mpox. During case management, the WECHU will determine on a case-by-case basis when self-isolation can be discontinued. For more information, please refer to Recommendations for the Management of Cases and Contacts of Mpox in Ontario.


The anti-viral tecovirimat (TPoxx) is available for mpox patients at risk (severely immunocompromised) or experiencing severe disease. For more information, please visit MPOX Antiviral Guidance for Health Care Providers and MPOX Antiviral Information Sheet


Imvamune® (authorized in Canada for protection against mpox) is a two-dose series, spaced apart by at least 28 days. Any clients that receive first and not second doses should complete the series. Clients can book and/or cancel an appointment by telephone at: 519-258-2146 ext. 1420. Currently, people who have or have had mpox are not eligible for the vaccine. For more information, please visit Mpox Vaccines- WECHU website and Imvamune Product Monograph


Please continue to report all suspected and confirmed cases of mpox to the Infectious Disease Department at WECHU using the reporting form. Reporting forms can be faxed to 226-783-2132. For questions or concerns please contact the WECHU at 519.258-2146 ext. 1420.