HEALTH UPDATE: PREVENT MPOX TRANSMISSION IN SUMMER 2023

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While cases of mpox (formerly called monkeypox) have declined in Santa Clara County and the United States, the outbreak is not over. Recently, Chicago has reported 23 mpox cases since April 2023. As noted in a health alert from Chicago, which reported the first 12 confirmed and one probable cases from this cluster, nine out the first 13 (69%) cases were fully vaccinated. For the nine out of 13 cases for which travel history was available, four had traveled recently (three traveled within the US, one traveled out of the country). None of the patients required hospitalization.
 
This cluster shows the need to continue to remain vigilant about mpox. As noted in a recent CDC health update, the summer season, when people gather for festivals and events, could bring a resurgence of cases, and steps towards prevention are important.

Providers are encouraged to take the following steps:

1. Provide mpox vaccination with two doses of the JYNNEOS vaccine to all eligible persons and offer either subcutaneous or intradermal routes of vaccination depending on patient preference.
2. Maintain capacity to offer JYNNEOS vaccination by ensuring supply and procedures are up-to-date.
3. Continue to counsel all patients, even those vaccinated for mpox, to avoid close, skin-to-skin contact with someone who has mpox or a rash suspicious for mpox.
4. Continue to consider mpox when evaluating a diffuse or localized rash and report suspected and confirmed cases of mpox to the County of Santa Clara Public Health Department by calling 408-792-3720.
5. Manage patients with mpox with supportive care and treatment with tecovirimat for those patients who may need it.
6. Continue to test for sexually transmitted infections, including HIV, gonorrhea, chlamydia, and syphilis in all patients suspected of having mpox.
7. Adopt a comprehensive approach to sexual health by ensuring STI and HIV prevention messaging along with mpox prevention.

Detailed information and additional resources regarding mpox:

1. Provide mpox vaccination with two doses of the JYNNEOS vaccine to all eligible persons and offer either subcutaneous or intradermal routes of vaccination depending on patient preference.

New data from two case control studies, one conducted in New York and another in 12 U.S jurisdictions, show that the JYNNEOS vaccine is efficacious, with vaccine effectiveness rates ranging from 86-88% after receiving two doses of the vaccine. Another study using data from a national Electronic Health Record database found that vaccine effectiveness was 66% after receiving two doses of the vaccine. These studies show that the vaccine is effective and should be offered to those with high potential for exposure. Although new mpox cases may occur in previously vaccinated people, those who are vaccinated may experience less severe symptoms, hence vaccination remains important.
 
Vaccination is encouraged for the following people  (note that an extensive risk assessment should not be conducted in people who request vaccination in order to avoid barriers created by stigma):

• People with a known or suspected exposure to mpox
• Gay, bisexual, and other men who have sex with men, and transgender or nonbinary people who in the past 6 months have either had a sexually transmitted infection or more than one sex partner
• People who in the past 6 months have had sex at a commercial sex venue or in association with a large public event or who have had sex in exchange for money or other items
• People who are sex partners of those with the above risks
• People who anticipate experiencing any of the above scenarios
• People with HIV or other causes of immunosuppression who anticipate potential mpox exposure
• People who work in settings where they may be exposed to mpox

In California, of the estimated population at risk for mpox, only 39% have been fully vaccinated indicating the need to continue to offer vaccination.  
 
JYNNEOS is administered as a 2-dose series 28 days apart; at this time no booster doses are recommended. The vaccine may be administered either through the subcutaneous route or the intradermal route. Patients with concerns about intradermal administration due to stigma or other personal reasons should be offered subcutaneous doses. If your clinic does not have vaccination capability, patients can obtain free vaccination through the county public health department and upcoming events where the public health department is partnering to offer vaccines.

2. Maintain capacity to offer JYNNEOS vaccination by ensuring supply and procedures are up-to-date.

Clinics should ensure that they have an adequate supply of JYNNEOS vaccination. For those clinics that are interested in offering JYNNEOS or need to obtain more vaccine doses, please contact the County of Santa Clara Public Health Pharmacy Team at medicalsupply@phd.sccgov.org for more information.

3. Continue to counsel all patients, even those vaccinated for mpox, to avoid close, skin-to-skin contact with someone who has mpox or a rash suspicious for mpox.

All persons, even those previously vaccinated for mpox, should be counseled to avoid close contact with someone with mpox. Regardless of vaccination status, all individuals with potential exposures should monitor for symptoms for 21 days. All persons with mpox should be counseled to try and isolate until infection has resolved. Post-exposure prophylaxis (PEP) with JYNNEOS can be given to those with known or presumed exposure to mpox; PEP is most effective when given within 4 days of exposure but may still provide some protection when given 4 to 14 days after exposure.

4. Continue to consider mpox when evaluating a diffuse or localized rash.

Consider mpox when evaluating a diffuse or localized rash and perform a complete physical examination, including a thorough skin and mucosal examination, for patients with a rash. A detailed sexual history is also important in any patient with suspected mpox. Notify all suspected and confirmed cases of mpox to the County of Santa Clara Public Health Department by calling 408-792-3720.

5. Manage patients with mpox with supportive care and treatment with tecovirimat for those patients who may need it.

 Mpox can cause severe pain, and patients with mpox can benefit from supportive care. Topical and oral therapies to manage pain should be considered. Tecovirimat is an oral medication that is available for treatment and should be considered in people who have severe disease, lesions at sensitive anatomic sites, or those who are at high risk for severe disease. Providers who wish to prescribe tecovirimat, but do not currently have access to it, can call the County of Santa Clara Public Health Department (408-792-3720) for assistance in obtaining it.

6. Continue to test for sexually transmitted infections, including HIV, gonorrhea, chlamydia, and syphilis in all patients suspected of having mpox.

HIV and other sexually transmitted infections (STIs) have been highly prevalentamong persons with mpox. It is important to screen all suspected patients with mpox for these STIs. For gonorrhea and chlamydia, screening should be done at all sites of potential exposure. All STIs should be treated in accordance with the 2021 CDC STI treatment guidelines. Note that the diagnosis of a STI does not exclude mpox since concurrent infection can occur.

7. Adopt a comprehensive approach to sexual health by ensuring STI and HIV prevention messaging along with mpox prevention.

Along with promoting vaccinations for mpox among those who are eligible, providers should ensure that prevention strategies for HIV and STIs are offered. Pre-exposure Prophylaxis (PrEP) to prevent HIV and doxy-PEP to prevent bacterial STIs, along with vaccination for sexually associated infections including Meningococcal ACWY vaccine, Hepatitis A, Hepatitis B, HPV vaccine, should be discussed with eligible patients.

References:

1. Resurgence of Mpox-Provider Update: May 9, 2023. Chicago Department of Public Health. 2023.  
2. Potential Risk for New Mpox Cases. Centers for Disease Control and Prevention. 2023.
3. Effectiveness of JYNNEOS Vaccine Against Diagnosed Mpox Infection — New York, 2022. MMWR Morb Mortal Rep. 2023.
4. Estimated Effectiveness of JYNNEOS Vaccine in Preventing Mpox: A Multijurisdictional Case-Control Study — United States, August 19, 2022–March 31, 2023. MMWR Morb Mortal Rep. 2023.
5. Vaccine Effectiveness of JYNNEOS against Mpox Disease in the United States. New England Journal of Medicine. 2023.
6. Demographic and Clinical Characteristics of Mpox in Persons Who Had Previously Received 1 Dose of JYNNEOS Vaccine and in Unvaccinated Persons — 29 U.S. Jurisdictions, May 22–September 3, 2022. MMWR Morb Mortal Rep. 2022.
7. JYNNEOS Vaccine Coverage by Jurisdiction. Centers for Disease Control and Prevention. Accessed May 2023.
8. Interim Clinical Considerations for Use of JYNNEOS and ACAM2000 Vaccines during the 2022 U.S. Mpox Outbreak. Centers for Disease Control and Prevention. Accessed May 2023.
9. Patient and Provider Choice on Route of Administration of Jynneos Mpox Vaccine. California Department of Public Health. 2023.
10. Monkeypox or mpox. County of Santa Clara Public Health Department. Accessed 2023.
11. Isolation and Infection Control At Home. Centers for Disease Control and Prevention. Accessed May 2023.
12. Clinical Considerations for Pain Management of Mpox. Centers for Disease Control and Prevention. Accessed May 2023.
13. Guidance for Tecovirimat Use. Centers for Disease Control and Prevention. Accessed May 2023.
14. HIV and Sexually Transmitted Infections Among Persons with Monkeypox — Eight U.S. Jurisdictions, May 17–July 22, 2022. MMWR Morb Mortal Rep. 2022
15. 2021 CDC STI treatment guidelines. Centers for Disease Control and Prevention.2021
16. HIV prevention PrEP and PEP. County of Santa Clara Public Health Department. Accessed 2023.
17. Doxycycline use as post-exposure prophylaxis to prevent bacterial sexually transmitted infections. County of Santa Clara Public Health Department. 2023

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    Original notice from County of Santa Cara Public Health Department on May 22, 2023.