Public Health Guidance for Monkeypox

Overview

Monkeypox outbreaks in the United States have allowed health authorities to learn more than ever before about disease epidemiology, case trends, transmission, clinical management, and prevention.

Health departments and agency collaborations play an enormous role in helping slow the spread of monkeypox. This success has been borne out through monkeypox-related surveillance expansion, laboratory capacity, case and data reporting efficiencies, risk communication messaging, and clinical guidance.

CDC offers recommendations for the clinical and public health management of monkeypox virus (MPXV) in the United States. This guidance may be updated based on trends seen in epidemiologic data and investigations performed in the United States and around the world.

Specifically, CDC recommends:

• Rapid clade-specific testing for any monkeypox patients with travel history to a country with ongoing clade I spread, or those who have had exposure to travelers from one of these countries
• Isolating people with possible clade I monkeypox while awaiting laboratory testing results, and afterward if results are positive for clade I MPXV.
• Active monitoring of high and intermediate risk exposure contacts

Because clade I cases have only recently been reported in the U.S., and because subclade Ib has been more recently described, CDC further recommends close clinician, state/local health department, and CDC collaboration to monitor the clinical course of patients with clade I monkeypox where possible. This monitoring will help increase understanding of the clinical severity and transmission patterns of clade I monkeypox in the United States.

Case definitions

Standardized national surveillance case definitions for monkeypox have been in place since 2022. Monkeypox is a national notifiable condition, and the Council for State and Territorial Epidemiologists (CSTE) recommends that all states and territories make monkeypox cases reportable in their jurisdiction. CDC has posted case definitions for clade I and clade II monkeypox to help with case surveillance and guide clinical decision-making.

Planning strategies

Monkeypox vaccination

Vaccination remains an important yet underutilized tool in stopping the spread of monkeypox. The size of a potential monkeypox outbreak varies with a county's population immunity from vaccination coverage and previous monkeypox case rates. In counties with immunity greater than 50 percent, outbreaks are expected to be smaller. In communities with immunity less than 50 percent, more people being vaccinated against monkeypox can reduce the risk of an outbreak.1

Monkeypox vaccination strategies are likely to be most effective when designed and implemented in partnership with communities and groups that are disproportionately affected.

Include monkeypox vaccination as part of broader prevention activities and routine sexual health care. For example:

• Help patients understand if they may be at risk for the disease in the United States or during travel to areas with sustained clade I or new clade II outbreaks.
• Discuss behavioral strategies to minimize risk when vaccine is not an option for the patient.
• Offer monkeypox vaccine alongside other vaccines like COVID-19 or flu vaccine.
• Include monkeypox prevention in discussions about HIV PEP, HIV PReP, or doxy PEP with patients and clients.
• Allow individuals to self-attest their vaccine eligibility (i.e., providing monkeypox vaccination without requiring individuals to specify which criterion they meet).
• Include monkeypox education and offer the vaccine during public health events and activities including:
  • Community health fairs
  • On-site vaccination events when groups of people disproportionately impacted by monkeypox may get together
  • Mobile testing vans
  • Street outreach

Clinical guidance

Most patients with monkeypox who don't have severe disease or risk factors for severe disease (e.g., severe immunocompromise) will recover with supportive care and pain control.

CDC has interim clinical guidance to assist clinicians in managing patients with severe manifestations of monkeypox. Treatment for these patients involves FDA–regulated drugs and biologics that are primarily stockpiled by the U.S. government for smallpox preparedness.

Currently there is no Food and Drug Administration (FDA)-approved treatment specifically for monkeypox. However, some patients may experience severe manifestations of monkeypox and may require additional treatment. These severe manifestations include:

• Ocular infections
• Neurologic complications
• Myopericarditis
• Complications associated with mucosal (oral, rectal, genital) lesions
• Complications from uncontrolled viral spread due to moderate or severe immunocompromise, particularly advanced HIV infection or those with certain skin conditions

Diagnosis and testing

CDC recommends clinicians and jurisdictions in the United States maintain a heightened index of suspicion for monkeypox in patients who present with a new rash characteristic of MPXV infection.

If monkeypox is suspected, clinicians should contact their state/local public health laboratory (PHL) to order real-time PCR-based tests for testing as per CDC clinical testing guidance. CDC guidelines for collection and handling specimens for monkeypox testing help clinicians safely manage specimens. PHLs should prioritize clade testing for individuals with recent travel to countries with community clade I transmission.

Diagnostic and clade-specific testing considerations

• Diagnostic specimens from both monkeypox clades have the same biosafety considerations, but specimens identified as confirmed clade I MPXV are regulated as select agents.
• The CDC-developed, FDA 510(k)-cleared, non-variola orthopoxvirus (NVO) test will detect both clades and all known subclades of MPXV but is unable to distinguish between them.
• Multiple laboratories in the United States currently perform clade-specific testing (via PCR and/or sequencing). Some of these laboratories use an emergency use authorized multi-target PCR test where specimens that are NVO positive and clade II negative are flagged for additional testing.
• CDC also provides clade differentiation testing on NVO-positive specimens referred from many U.S. laboratories.
• In addition, several PHLs in the United States have developed MPXV-clade-specific laboratory developed tests (LDT) to expand testing capacity.
• CDC is developing a monkeypox triplex assay that includes an NVO target along with clade I- and clade II-specific targets.

Infection prevention and control

Follow CDC's guidance for infection prevention and control of monkeypox in various settings:

Contact tracing

Conduct a public health interview to get names and contact information for all high- and intermediate-risk contacts going back 4 days prior to illness onset and ending with the resolution of the illness (or the time of the interview, if illness is not resolved). Begin contact tracing while laboratory confirmation of monkeypox is pending. Any probable or confirmed case of monkeypox, regardless of clade, should be reported within 24 hours to the state/local health department. At this time, eliciting and notifying contacts of those people identified as contacts of monkeypox cases ("contacts of contacts", or secondary contact tracing), is not expected to be useful.

Post-exposure risk assessment, monitoring, and prophylaxis recommendations

Contact monitoring for monkeypox is based on exposure risk. CDC also has guidance for Risk Assessment and Monitoring in Healthcare Settings and Risk Assessment and Monitoring in Community Settings.

Public health notification

Clinicians diagnosing either clade of monkeypox should follow state and/or local monkeypox reporting requirements. We also strongly encourage clinicians and health departments to collaborate to submit case information as per CDC case reporting recommendations.

If the patient has a potential epidemiologic link to clade I monkeypox, clinicians should promptly contact the state and/or local health department where the patient resides to report the possibility of a clade I monkeypox case. CSTE maintains 24/7 Epidemiology on-call numbers for states and large cities.

Resources

Health alert network