Monkeypox (Mpox) is an endemic Orthopox virus in West and Central Africa. Mpox is now occurring in other countries, causing major healthcare concerns. Most human Mpox infections are reported from the Congo Basin of the Democratic Republic of Congo (Hughes et al., 2021). Mpox is most commonly found in rural, forested communities with poor sanitation and chronic malnutrition (Beer & Rao, 2019). However, as of January 25th, 2023, there were 30,093 total confirmed Mpox/Orthopoxvirus cases in the United States (Centers for Disease Control and Prevention [CDC], 2022b).
In November 2022, the World Health Organization (WHO) sent out a news release regarding Mpox. Due to the outbreak expansion over the past year that exposed racist and stigmatizing language, after consultation with several global experts as well as the general public, WHO recommended a new name for "Monkeypox" (World Health Organization [WHO], 2022b). "Mpox" was recommended to become the preferred term, to replace "Monkeypox" after a period of one year, to allow time for the transitioning of all policies and procedures to reflect the new name as well as for the International Classification of Diseases (ICD) to adopt the new term for medical coding purposes (WHO, 2022b).
Mpox cases are being reported sporadically around the world. It is believed to have spread worldwide due to the lack of immunization after the smallpox vaccine was stopped (Grant et al., 2020). Therefore, people who did not receive a smallpox vaccine (those younger than 40-50 years of age) may be susceptible.
Mpox is categorized into 2 genetic clades. These include the genetic clades of West Africa and Central Africa (also called Congo Basin). These clades have epidemiological and clinical differences. The mortality rate of the West African clade is less than 1%, and there is no human-to-human transmission. The Central African clade is more frequent, can have a mortality of up to 11%, and has human-to-human transmission (Singh et al., 2021). Beer and Rao (2019) conducted a systematic review of the research published in English before August 15, 2018. They found an often-quoted 10% mortality rate. This rate came from early 1981-1986 data: 33 deaths out of 338. Data from the Democratic Republic of Congo (2001-2013) consistently reported mortality of <5%. Case fatality rate (CFR) from countries with the West African Mpox were mostly 0%. The mortality for the Nigeria outbreak was 2.8%. Six deaths, 4 of whom were immunocompromised, out of 228 suspect cases. The mortality for 47 cases in United States outbreaks was 0%. No deaths have been reported from the April 2018 outbreak in Cameroon or the recent outbreak in the Central African Republic. In reports documenting the cause of death, people in high-risk groups comprised most of the deaths (Beer & Rao, 2019).
Because of inconsistencies in healthcare and surveillance systems in rural African settings, Mpox data is incomplete and unreliable (Beer & Rao, 2019). This unreliable data is insufficient for statistical analysis (Beer & Rao, 2019). Due to the clinical overlap and insufficient laboratory availability, varicella-zoster virus (VZV) is often misdiagnosed as Mpox, and the conditions may be co-infected in the same patient (Beer & Rao, 2019; Hughes et al., 2021). There is some suggestion that Mpox is increasing in incidence. Data in more developed countries is more reliable.
Below is the Mpox Outbreak Global Map with data as of January 29th, 2023, directly from the CDC:
Mpox Outbreak Global Map
Centers for Disease Control and Prevention (January 29th, 2023)
As included in the legend, the orange circles indicate areas of reported cases of Mpox that historically had not had cases in prior outbreaks. The blue circles indicate areas that had. For more information and specific numbers, feel free to visit the CDC here.