Although reported cases of mpox in the United States have significantly declined since the outbreak peak in the summer of 2022, small clusters have continued to occur. Severe mpox manifestations, including deaths, also continue to occur. Currently, only one in four of the approximately 2 million people eligible to receive JYNNEOS in the United States have received both doses. The Centers for Disease Control and Prevention (CDC) encourages providers to remain diligent about taking their patient’s sexual history and recommending the two-dose JYNNEOS vaccine to those who are eligible to help reduce the risk of continued mpox transmission.

In October 2023, the Advisory Committee on Immunization Practices recommended that people 18 years and older who are at risk or potential risk for mpox receive two doses of the JYNNEOS vaccine 28 days apart. The vaccine is safe and effective in preventing or minimizing the severity of mpox. CDC strongly urges clinicians, health departments, and community-based organizations to continue recommending the two dose JYNNEOS vaccine to eligible people and to encourage patients who have only received one dose to get the second dose to have the best protection. The vaccine is FDA-approved for prevention of mpox, regardless of the Clade. 

Jurisdictions that are interested in exploring funding options for vaccine-related services for mpox response should consider the availability of their jurisdiction’s awarded CDC Mpox Public Health Crisis Response funding. CDC recommends contacting your jurisdiction’s principal investigator to explore funding options and opportunities. 

In December 2023, CDC issued a Health Alert Network (HAN) health advisory to notify clinicians and health departments about the Clade I monkeypox virus (MPXV) outbreak in the Democratic Republic of the Congo (DRC). Clade I MPXV is associated with more severe illness and is genetically distinct from the Clade II MPXV that has been circulating in the United States since May 2022. To-date, no Clade I cases have been identified in the United States; however, Clade I spreads similarly to Clade II MPXV, and clinicians should be aware of the possibility of Clade I MPXV in travelers from the DRC. JYNNEOS vaccine and other medical countermeasures (e.g., tecovirimat, brincidofovir) are available and expected to be effective for both Clade I and Clade II MPXV infections. For testing purposes, clinicians need to collect two swabs from a suspect mpox lesion, so that MPXV clade-specific testing can be performed if necessary.