Mpox in the Democratic Republic of the Congo | |
---|---|
Disease | Mpox |
Virus strain | Monkeypox virus |
Source | Initially mainly animal contact in rainforest, later greater human-to-human transmission |
Location | Democratic Republic of the Congo |
Mpox is endemic in western and central Africa, with the majority of cases occurring in the Democratic Republic of the Congo (DRC), where the disease is reportable. [1] [2] There, the more virulent clade I has been affecting some of the world's poorest and socially excluded communities. [3]
Many cases occur sporadically or in small clusters, but large outbreaks also occur. [2]
The world's first case of human mpox was detected in a nine-month old child in 1970 in the Democratic Republic of the Congo (then Zaire), [4] [5] two years after it reported its last case of smallpox. [6] The onset of their rash was on 24 August. [7] That year, the disease was identified in another four children, including three in Liberia who were playmates. [8] At the time, evidence of the virus was found in non-human primates in Liberia and Sierre Leone. [8]
Active surveillance by the World Health Organization (WHO) between 1981 and 1986, identified 338 cases with a human-to-human transmission rate of 28%. [9] [10] Until 1986, 95% of cases worldwide were identified in the DRC. [11] Cases were rare in people over the age of 15-years, and over two-thirds of infections could be traced to animal contact within the rainforests. [12] Initially it was uncommon for a family member to contract the infection unless they did not have a smallpox scar. [12]
A reemergence of the disease in the DRC in 1996 also saw a large number of reported but not all laboratory confirmed cases, with a high transmission rate and lower fatality rate; leading experts to believe a significant number may have actually been chicken pox. [10] [13] Some likely had both mpox and chickenpox at the same time. [6] The DRC's Kasaï-Oriental region saw the largest number of cases during 1996–1997. [6]
Between 1996 and 2005, mpox cases appeared increasingly in gradually older people, with less than a quarter of cases being traced to rainforest animal contact, and with greater close contact infections. [12] Between January 2001 and December 2004, 2,734 cases of suspected human mpox were reported from the DRC. [10] However, civil war limited surveillance and only 171 clinical specimens were obtained from 136 suspected cases; less than 5% of all reported cases. [10]
After 2005, the DRC was reporting more than 1000 suspected cases per year. [14] Between November 2005 and November 2007, 760 laboratory-confirmed human mpox cases were detected; particularly in people living in forested areas, males, age less than 15-years, and no previous smallpox vaccination. [15]
Many cases occur sporadically or in small clusters, but large outbreaks also occur. [2] The risk of human-to-human transmission within households in the DRC was noted to range from 50% to 100% during the 2013 outbreak. [6] The DRC's Bokungu Health Zone saw an increase in cases of 600-fold that year. [2] In 2019 the DRC reported 3,794 suspected cases and 73 deaths. [11] In the first nine-months of 2020, it reported over 4,500 suspected cases of mpox, including 171 deaths. [11]
Mpox is reportable in the DRC, where the disease is endemic, and disease burden remains high. [2] [16] There, the more virulent clade I has been affecting some of the world's poorest and socially excluded communities. [3] A regional surveillance system collects reports of all suspected mpox cases, and where possible, they may be investigated. [2]
During 2023, a Clade I outbreak of mpox disease in the DRC resulted in 14,626 suspected cases being reported, with 654 associated deaths, making for a case-fatality rate (CFR) of 4.5%. The outbreak continued into 2024 with an additional 3,576 suspected mpox cases and 265 deaths being reported in the DRC through the first 9 weeks of the year, making for an estimated CFR of 7.4%. [17]
The outbreak appears to be of a primarily sexually transmitted nature and cases are occurring in areas without a history of mpox, such as South Kivu and Kinshasa. The outbreak seems to consist of two separate sub-variants of clade I, with one of the sub-variants having a novel mutation making detection with standard assays unreliable. [17]
The outbreak spread to the neighbouring country of the Republic of Congo, with 43 mpox cases being reported in March 2024. [17]
Mpox in the Democratic Republic of the Congo | |
---|---|
Disease | Mpox |
Virus strain | Monkeypox virus |
Source | Initially mainly animal contact in rainforest, later greater human-to-human transmission |
Location | Democratic Republic of the Congo |
Mpox is endemic in western and central Africa, with the majority of cases occurring in the Democratic Republic of the Congo (DRC), where the disease is reportable. [1] [2] There, the more virulent clade I has been affecting some of the world's poorest and socially excluded communities. [3]
Many cases occur sporadically or in small clusters, but large outbreaks also occur. [2]
The world's first case of human mpox was detected in a nine-month old child in 1970 in the Democratic Republic of the Congo (then Zaire), [4] [5] two years after it reported its last case of smallpox. [6] The onset of their rash was on 24 August. [7] That year, the disease was identified in another four children, including three in Liberia who were playmates. [8] At the time, evidence of the virus was found in non-human primates in Liberia and Sierre Leone. [8]
Active surveillance by the World Health Organization (WHO) between 1981 and 1986, identified 338 cases with a human-to-human transmission rate of 28%. [9] [10] Until 1986, 95% of cases worldwide were identified in the DRC. [11] Cases were rare in people over the age of 15-years, and over two-thirds of infections could be traced to animal contact within the rainforests. [12] Initially it was uncommon for a family member to contract the infection unless they did not have a smallpox scar. [12]
A reemergence of the disease in the DRC in 1996 also saw a large number of reported but not all laboratory confirmed cases, with a high transmission rate and lower fatality rate; leading experts to believe a significant number may have actually been chicken pox. [10] [13] Some likely had both mpox and chickenpox at the same time. [6] The DRC's Kasaï-Oriental region saw the largest number of cases during 1996–1997. [6]
Between 1996 and 2005, mpox cases appeared increasingly in gradually older people, with less than a quarter of cases being traced to rainforest animal contact, and with greater close contact infections. [12] Between January 2001 and December 2004, 2,734 cases of suspected human mpox were reported from the DRC. [10] However, civil war limited surveillance and only 171 clinical specimens were obtained from 136 suspected cases; less than 5% of all reported cases. [10]
After 2005, the DRC was reporting more than 1000 suspected cases per year. [14] Between November 2005 and November 2007, 760 laboratory-confirmed human mpox cases were detected; particularly in people living in forested areas, males, age less than 15-years, and no previous smallpox vaccination. [15]
Many cases occur sporadically or in small clusters, but large outbreaks also occur. [2] The risk of human-to-human transmission within households in the DRC was noted to range from 50% to 100% during the 2013 outbreak. [6] The DRC's Bokungu Health Zone saw an increase in cases of 600-fold that year. [2] In 2019 the DRC reported 3,794 suspected cases and 73 deaths. [11] In the first nine-months of 2020, it reported over 4,500 suspected cases of mpox, including 171 deaths. [11]
Mpox is reportable in the DRC, where the disease is endemic, and disease burden remains high. [2] [16] There, the more virulent clade I has been affecting some of the world's poorest and socially excluded communities. [3] A regional surveillance system collects reports of all suspected mpox cases, and where possible, they may be investigated. [2]
During 2023, a Clade I outbreak of mpox disease in the DRC resulted in 14,626 suspected cases being reported, with 654 associated deaths, making for a case-fatality rate (CFR) of 4.5%. The outbreak continued into 2024 with an additional 3,576 suspected mpox cases and 265 deaths being reported in the DRC through the first 9 weeks of the year, making for an estimated CFR of 7.4%. [17]
The outbreak appears to be of a primarily sexually transmitted nature and cases are occurring in areas without a history of mpox, such as South Kivu and Kinshasa. The outbreak seems to consist of two separate sub-variants of clade I, with one of the sub-variants having a novel mutation making detection with standard assays unreliable. [17]
The outbreak spread to the neighbouring country of the Republic of Congo, with 43 mpox cases being reported in March 2024. [17]