Monkeypox Virus Detected in Hamilton Wastewater
Hamilton Public Health Services (PHS) is notifying health care providers of the detection of monkeypox virus in Hamilton’s wastewater. While the mpox outbreak has been declared over, the detection of monkeypox virus in wastewater may indicate undiagnosed sporadic mpox cases. There have been no cases of mpox reported to Hamilton PHS since September 16, 2022.
Signs & Symptoms
Monkeypox is an orthopoxvirus that causes mpox, a disease similar to, but less severe than smallpox. The disease is usually mild and self-limiting, however severe illness can occur. Mpox infection presents with prodrome symptoms of fever, chills, headache, myalgias, lymphadenopathy, and fatigue, followed one to three days later by a progressively developing rash. The rash typically begins on the face, then spreads to other parts of the body, including the hands, feet, mouth, genital, and/or peri-anal region.
Action Required
Hamilton PHS is requesting health care providers to:
- Consider mpox as a differential diagnosis in individuals presenting with compatible clinical illness. While gbMSM are at highest risk, anyone with close personal contact could also be at risk for infection.
- Continue to consider the following differential diagnoses, which may be hard to distinguish from mpox, such as syphilis, herpes simplex virus, chancroid etc.
- Recommend Imvamune® vaccine as pre-exposure prophylaxis (PREP) to eligible individuals. Imvamune® is given as a two-dose primary series, with at least 28 days between the first and second dose.
- Encourage patients who have had one dose of Imvamune® vaccine to complete their two-dose series. A second dose is required to maintain protection. Currently, the rate for second doses administered is extremely low in Hamilton at 9.03%.
- Place individuals with compatible mpox infection in a single room with a closed door upon arrival. Ensure appropriate PPE is worn, including a fit-tested, seal-checked N95 respirator, eye protection, gloves and a gown. Patients should wear a medical mask for source control.
Testing
The Public Health Ontario Laboratory has a Monkeypox virus test information sheet which can be found at https://www.publichealthontario.ca/en/Laboratory-Services/Test-Information-Index/Monkeypox-Virus. Note: For patients with skin lesions that can be swabbed or skin lesion material (e.g. scabs), NP/throat swabs and blood specimens are usually not recommended. This is because skin lesions have higher viral loads, therefore submitting swabs or skin lesion material (e.g. scabs) are more sensitive to virus detection. For patients who do not have a skin rash (e.g. close contact with febrile illness but no rash) or their skin rash can’t be reliably swabbed (e.g., macular or popular rash only), blood should always be submitted along with a nasopharyngeal swab or throat swab. Anal or rectal swabs are recommended for patients with lesions in these locations, or symptoms of involvement (e.g. rectal pain). Refer to the test information sheet for details.
Vaccination
Hamilton Public Health Services offers mpox vaccination for at-risk populations at our Sexual Health Clinic located at the David Braley Health Sciences Centre. Individuals who meet the provincial criteria for vaccination to prevent mpox infection can book an appointment by calling our Sexual Health Info Line at 905-528-5894, Monday to Friday from 08:30 am to 4:30 pm. An OHIP card is not required. The next mpox clinic is Wednesday, December 20, 2023. The clinic will be offered again in the new year on Wednesday January 3, 2024.
Reporting Requirements
Mpox disease is reportable to the Medical Officer of Health under the Health Protection and Promotion Act, R.S.O. 1990, c. H.7.
Reporting to Public Health Services
To report suspect and confirmed mpox cases, call Hamilton Public Health Services Monday to Friday, 8:30 am. to 4:30 pm at 905-546-2063 or fax reports to 905-546-4078. After hours and on weekends, call 905-546-2063 and ask to speak with a Public Health Nurse.