Overview
CDC has been actively involved in mpox outbreak preparedness, response, and research for more than 20 years. CDC adapts scientific risk assessments to epidemiological findings, research results, and other outbreak learnings. CDC also uses data from these outbreaks and patterns of disease spread in the United States and other countries to model the potential spread of mpox in the United States. Such assessments can also lead to public health guidance and recommendations.
CDC Public Health Science Agenda for Clade I Mpox - October 2024
The U.S. Centers for Disease Control and Prevention (CDC) established a clade I mpox emergency response on March 13, 2024, to address the outbreak of clade I mpox in the Democratic Republic of the Congo (DRC) and neighboring countries. The CDC mission includes providing a range of CDC support for the clade I mpox outbreak response in DRC and bordering countries and ensuring domestic preparedness to rapidly detect and respond to case(s) of clade I mpox in the United States, if they occur.
The Democratic Republic of the Congo (DRC) is experiencing the highest number of mpox cases on record for that country; the number of 2024 cases reported for the clade I mpox outbreak is the highest number of cases ever recorded for a year. As of December 30, 2024, the neighboring countries of Burundi, Rwanda, Central African Republic, Republic of the Congo, and Uganda are also experiencing outbreaks; travel-associated cases have been reported in Belgium, Canada, Germany, India, Kenya, Oman, Sweden, Thailand, the United Kingdom, the United States, Zambia, and Zimbabwe.
The first case of clade I mpox was reported in the United States in November 2024. This case is related to the outbreak in Central and Eastern Africa. The anticipated overall risk of mpox to the general population in the United States from the 2024 clade I mpox outbreak remains low. There remains concern about the outbreak and the potential for sustained clade I Monkeypox virus (MPXV) transmission outside of endemic countries.
To help guide understanding of MPXV and mpox disease, CDC has identified the following scientific and research objectives for the current outbreak of clade I mpox.
- Determining the effectiveness of mpox vaccines at preventing circulating clade I virus.
- Determining the vaccination strategies (e.g., populations eligible for vaccination, ring vaccination, pre-exposure vaccination) effective at protecting different groups from clade I mpox in various settings.
- Evaluating the difference in effectiveness between strategies, depending on vaccine type.
- Evaluating the difference in effectiveness between strategies, depending on vaccine type.
- Understanding vaccine uptake, interventions to improve uptake, perceptions, and hesitancy among populations eligible for vaccination.
- Determining the degree and duration of immunity provided by a previous mpox or smallpox vaccine.
- Evaluating the difference between populations.
- Evaluating the difference between populations.
- Determining the effectiveness of each mpox vaccine within particular populations and settings (e.g., resource rich vs resource limited, global vs domestic).
- Determining the degree and duration of immunity a previous MPXV infection provides.
- Describing the population-level immunity to mpox in DRC and other endemic countries
- Identifying the proportion of the population that has previously been infected with orthopoxviruses.
- Identifying the proportion of the population that has previously been infected with orthopoxviruses.
- Evaluating interventions (e.g., therapeutics, clinical support, contact tracing, behavior modifications, infection prevention and control at facilities and in communities), programs, and communication approaches that are effective for Clade I mpox prevention in various settings
- Reducing transmission among different populations.
- Increasing equitable access to prevention strategies.
- Increasing uptake of prevention strategies.
- Reducing transmission among different populations.
- Understanding knowledge, attitudes, & awareness of mpox and mpox prevention strategies among priority populations including health care providers.
- Determining the impact of genetic characteristics of the virus on detection using currently available diagnostic tests.
- Validating point-of-care molecular testing for resource-limited settings.
- Evaluating the effectiveness of the CDC-developed triplex PCR assay (non-variola orthopoxvirus (NVO), clade II and clade Ia targets) in detecting clade I MPXV.
- Describing the sensitivity of the NVO test in areas where clade Ib is circulating.
- Describing the sensitivity of the NVO test in areas where clade Ib is circulating.
- Determining the performance characteristics (i.e., sensitivity and specificity) of the new point-of-care and/or field-deployable diagnostic tests at detecting MPXV.
- Describing the impact of genetic characteristics of the virus on clinical presentation and outcomes.
- Describing the impact of genetic characteristics of the virus on the effect of therapeutics (e.g., effectiveness, duration of effectiveness).
- Evaluating the comparative effectiveness of treatment strategies, including combination therapy and supportive care alone, at reducing morbidity and mortality of clade I mpox in resource-limited and resource-rich settings.
- Determining if clinical presentation differs by route or type of exposure.
- Determining the causes of resistance to therapeutics.
- Evaluating the impact of viral resistance to mpox treatment on clinical outcomes.
- Describing the clinical presentation and disease course of clade I mpox in various settings.
- Evaluating the impact of viral resistance to mpox treatment on clinical outcomes.
- Determining the proportion of rash illnesses suspected to be mpox that are caused by MPXV in DRC.
- Determining which interventions are most effective in various settings for increasing access to equitable clinical care for people with clade I mpox.
- Understanding facilitators and barriers to providing clinical care (testing, diagnosis and treatment) among health care providers/health care system.
- Describing the transmission dynamics for clade I mpox.
- Describing the impact of genetic characteristics of circulating viruses on virulence and transmission dynamics.
- Determining which populations are most at risk for clade I MPXV infection.
- Evaluating any difference in epidemiologic characteristics between clade Ia and Ib.
- Evaluating any difference in epidemiologic characteristics between clade Ia and Ib.
- Describing the trajectory of the current outbreak.
- Describing the circumstances in which surges in various environments (e.g., endemic vs non-endemic) are likely to occur in the future.
- Determining effective strategies for surveillance of clade I MPXV and/or mpox disease.
- Evaluating the effectiveness of wastewater surveillance in detecting clade I MPXV.
- Determining the key animal reservoirs for clade I MPXV in various settings.
- Determining whether there is a difference between animal reservoirs for clade Ia and Ib.
- Determining which non-African species are susceptible to infection with clade I (a and b).
- Determining whether there is a difference between animal reservoirs for clade Ia and Ib.