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Epidemiology and Infection Jun 2023Although Africa is home to about 14% of the global population (1.14 billion people), it is growing three times faster than the global average [1]. The continent carries...
Although Africa is home to about 14% of the global population (1.14 billion people), it is growing three times faster than the global average [1]. The continent carries a high burden of disease, but there has been real progress in eradication, elimination, and control since 2015. Examples are the eradication of wild polio in 2020 [2] and the eradication or elimination of neglected tropical diseases, such as dracunculiasis in Kenya in 2018; Human African trypanosomiasis in Togo in 2022; and trachoma in Togo, Gambia, Ghana, and Malawi in 2022 [3]. New HIV infections reduced by 44% in 2021 compared to 2010 [4], and in 2021 the African region passed the 2020 milestone of the End TB Strategy, with a 22% reduction in new infections compared with 2015 [5].
Topics: Humans; HIV Infections; Dracunculiasis; Ghana; Poliomyelitis; Cost of Illness; Disease Eradication
PubMed: 37337304
DOI: 10.1017/S0950268823000997 -
The American Journal of Tropical... May 2021The total number of Guinea worm cases has been reduced by 99.9% since the mid-1980s when the eradication campaign began. Today, the greatest number of cases is reported...
The total number of Guinea worm cases has been reduced by 99.9% since the mid-1980s when the eradication campaign began. Today, the greatest number of cases is reported from Chad. In this report, we use surveillance data collected by the Chad Guinea Worm Eradication Program to describe trends in human epidemiology. In total, 114 human cases were reported during the years 2010-2018, with highest rates of containment (i.e., water contamination prevented) in the years 2013, 2014, 2016, and 2017 (P < 0.0001). Approximately half of case-patients were female, and 65.8% of case-patients were aged 30 years or younger (mean: 26.4 years). About 34.2% of case-patients were farmers. Cases were distributed across many ethnicities, with a plurality of individuals being of the Sara Kaba ethnicity (21.3%). Most cases occurred between the end of June and the end of August and were clustered in the Chari Baguirmi (35.9%) and Moyen Chari regions (30.1%). Cases in the northern Chari River area peaked in April and in August, with no clear temporal pattern in the southern Chari River area. History of travel within Chad was reported in 7.0% of cases, and male case-patients (12.5%) were more likely than female case-patients (1.7%) to have reported a history of travel (P = 0.03). Our findings confirm that human Guinea worm is geographically disperse and rare. Although the proportion of case-patients with travel history is relatively small, this finding highlights the challenge of surveillance in mobile populations in the final stages of the global eradication campaign.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Animals; Chad; Disease Eradication; Dracunculiasis; Dracunculus Nematode; Epidemiologic Methods; Female; Forecasting; Humans; Male; Middle Aged; Population Surveillance; Young Adult
PubMed: 34029207
DOI: 10.4269/ajtmh.20-1525 -
MMWR. Morbidity and Mortality Weekly... Oct 2020Dracunculiasis (Guinea worm disease) is caused by the parasite Dracunculus medinensis and is acquired by drinking water containing copepods (water fleas) infected with...
Dracunculiasis (Guinea worm disease) is caused by the parasite Dracunculus medinensis and is acquired by drinking water containing copepods (water fleas) infected with D. medinensis larvae. The worm typically emerges through the skin on a lower limb approximately 1 year after infection, resulting in pain and disability (1). There is no vaccine or medicine to treat the disease; eradication efforts rely on case containment* to prevent water contamination. Other interventions to prevent infection include health education, water filtration, chemical treatment of unsafe water with temephos (an organophosphate larvicide to kill copepods), and provision of safe drinking water (1,2). The worldwide eradication campaign began in 1980 at CDC (1). In 1986, with an estimated 3.5 million cases occurring each year in 20 African and Asian countries (3), the World Health Assembly (WHA) called for dracunculiasis elimination (4). The global Guinea Worm Eradication Program (GWEP), led by the Carter Center and supported by the World Health Organization (WHO), United Nations Children's Fund, CDC, and other partners, began assisting ministries of health in countries with dracunculiasis. This report, based on updated health ministry data (4), describes progress made during January 2019-June 2020 and updates previous reports (2,4,5). With only 54 human cases reported in 2019, 19 human cases reported during January 2019-June 2020, and only six countries currently affected by dracunculiasis (Angola, Chad, Ethiopia, Mali, South Sudan, and importations into Cameroon), the achievement of eradication is within reach, but it is challenged by civil unrest, insecurity, and lingering epidemiologic and zoologic concerns, including 2,000 reported animal cases in 2019 and 1,063 animal cases in 2020, mostly in dogs. All national GWEPs remain fully operational, with precautions taken to ensure safety of program staff members and community members in response to the coronavirus disease 2019 (COVID-19) pandemic.
Topics: Animals; Disease Eradication; Dog Diseases; Dogs; Dracunculiasis; Global Health; Humans
PubMed: 33119555
DOI: 10.15585/mmwr.mm6943a2 -
British Medical Journal Jan 1980
Topics: Animals; Crustacea; Dracunculiasis; Dracunculus Nematode; Humans; Larva; Mummies
PubMed: 6444538
DOI: 10.1136/bmj.280.6208.183-d -
PLoS Neglected Tropical Diseases Aug 2021In the absence of a vaccine or pharmacological treatment, prevention and control of Guinea worm disease is dependent on timely identification and containment of cases to...
BACKGROUND
In the absence of a vaccine or pharmacological treatment, prevention and control of Guinea worm disease is dependent on timely identification and containment of cases to interrupt transmission. The Chad Guinea Worm Eradication Program (CGWEP) surveillance system detects and monitors Guinea worm disease in both humans and animals. Although Guinea worm cases in humans has declined, the discovery of canine infections in dogs in Chad has posed a significant challenge to eradication efforts. A foundational information system that supports the surveillance activities with modern data management practices is needed to support continued program efficacy.
METHODS
We sought to assess the current CGWEP surveillance and information system to identify gaps and redundancies and propose system improvements. We reviewed documentation, consulted with subject matter experts and stakeholders, inventoried datasets to map data elements and information flow, and mapped data management processes. We used the Information Value Cycle (IVC) and Data-Information System-Context (DISC) frameworks to help understand the information generated and identify gaps.
RESULTS
Findings from this study identified areas for improvement, including the need for consolidation of forms that capture the same demographic variables, which could be accomplished with an electronic data capture system. Further, the mental models (conceptual frameworks) IVC and DISC highlighted the need for more detailed, standardized workflows specifically related to information management.
CONCLUSIONS
Based on these findings, we proposed a four-phased roadmap for centralizing data systems and transitioning to an electronic data capture system. These included: development of a data governance plan, transition to electronic data entry and centralized data storage, transition to a relational database, and cloud-based integration. The method and outcome of this assessment could be used by other neglected tropical disease programs looking to transition to modern electronic data capture systems.
Topics: Animals; Chad; Disease Eradication; Dog Diseases; Dogs; Dracunculiasis; Dracunculus Nematode
PubMed: 34370746
DOI: 10.1371/journal.pntd.0009675 -
The American Journal of Tropical... Jan 2022Dracunculus medinensis, also known as the African Guinea worm, is the causative agent of dracunculiasis and the focus of the global Guinea Worm Eradication Program...
Dracunculus medinensis, also known as the African Guinea worm, is the causative agent of dracunculiasis and the focus of the global Guinea Worm Eradication Program (GWEP). Transmission of D. medinensis to humans occurs primarily by drinking water containing cyclopoid copepods infected with third-stage D. medinensis larvae. A common intervention to interrupt transmission and decrease the number of copepods in infected water bodies is the application of the organophosphate larvicide Abate® (temephos). However, the use of alternative compounds to help decrease copepod populations would be beneficial to the GWEP. We compared the immobilization of copepods by three compounds: Abate, Natular® (spinosad), and diflubenzuron. Our results confirm that neither diflubenzuron nor Natular immobilized copepods as quickly or as effectively as Abate. However, doubling or tripling the suggested concentration of Natular resulted in immobilization rates similar to Abate over 72 hours of continuous exposure. Further research on the possible effects of higher concentrations of Natular on the environment and nontarget organisms is necessary to determine whether this compound can be used safely to control the copepod population.
Topics: Animals; Copepoda; Diflubenzuron; Dracunculiasis; Dracunculus Nematode; Drug Combinations; Humans; Macrolides; Temefos
PubMed: 35073509
DOI: 10.4269/ajtmh.21-0818 -
Food and Waterborne Parasitology Sep 2020Waterborne parasitic diseases form one of common and important public health and economic problems in low- and middle-income countries, though little is known on the...
Waterborne parasitic diseases form one of common and important public health and economic problems in low- and middle-income countries, though little is known on the burden and patterns of these diseases in most regions. This systematic scoping review informs on the prevalence and pattern of waterborne parasitic infections in eastern Africa from 1st of January 1941 to 31st of December 2019. The review found limited number of published studies on waterborne parasitic diseases, though 13 of the 15 studied countries in eastern Africa provided one or more published report(s) totalling 47 reports. Focus of studies was mainly on schistosomiasis where 44.8% of the 47 retrieved studies reported it. Other frequently reported diseases were giardiasis (23.4% of reports), soil-transmitted helminths (23.4%) and amoebiasis (21.3%). Rarely reported diseases were malaria, cryptosporidiosis, isosporiasis, dracunculiasis and trichomoniasis. Based on parasitological examinations, schistosomiasis prevalence ranged from 17 to 33% in Burundi, 1.9 to 73.9% in Ethiopia, 2.1 to 18% in Kenya, 7.2 to 88.6% in Uganda, 22.9 to 86.3% in Tanzania, 27.2 to 65.8% in Somalia, 15 to >50% in Mauritius, 2.4% in Eritrea and 5.0 to 93.7% in Madagascar. Amoebiasis prevalence was 4.6-15,3% (Ethiopia), 5.9-58.3% (Kenya), 54.5% (Rwanda), 0.7-2.7% (Sudan), 19.93% (Uganda) and 4.5-5.0% (Seychelles). Giardiasis prevalence was 0.6-55.0% (Ethiopia), 16.6% (Kenya), 3.6% (Rwanda), 21.1% (Sudan), 40.7% (Uganda), 45.0% (Eritrea) and 3.3-6.0% (Seychelles). Soil-transmitted helminths prevalence was 41.7-52.4% (Ethiopia), 32.4-40.7% (Kenya), 9997 cases (Rwanda), 85.0% (Somalia), 4.7% (Madagascar) and 1.1-84% (Seychelles), , and hookworms were the most common helminths detected. Malaria prevalence was 2.9-4.31% (Ethiopia), an annual episode of 9 million people (Sudan), 13.0% (Tanzania), 146 hospital cases (Madagascar), 1.4-2.0% (Seychelles) and <5.0% in Djibouti. It is also observed that >50% of the populations in eastern Africa region lack improved drinking water sources or sanitation facilities. This may account for the observed high prevalence of the diseases. The author also suggests likely underestimation of the prevalence as most waterborne parasitic diseases are neglected and cases likely only recorded and left unpublished in health facilities. Thus for a thorough mapping of burdens of these diseases, grey literature, including hospital records must be reviewed while interventions focusing on improved water and sanitation are likely to reduce the burden considerably.
PubMed: 32995583
DOI: 10.1016/j.fawpar.2020.e00089 -
Emerging Microbes & Infections Oct 2012Patrick Manson, a clinician-scientist serving in China (1866-1889), discovered that many tropical infectious diseases require a vector peculiar to warm climate for... (Review)
Review
Patrick Manson, a clinician-scientist serving in China (1866-1889), discovered that many tropical infectious diseases require a vector peculiar to warm climate for person to person transmission. He demonstrated the nocturnal periodicity of microfilariae in the blood of patients with elephantiasis. These microfilariae undergo metamorphosis when ingested by the mosquito acting as the vector for the completion of their life cycle. Furthermore, he demonstrated the linkage between the lung fluke and endemic haemoptysis by finding operculated eggs in patients' sputa. He predicted that the miracidium from hatched eggs uses crustaceans, such as fresh-water snails found at tropical conditions, as the intermediate hosts in the life cycle of many trematodes. His vector hypothesis leads to vector control which is now the cornerstone for the World Health Organization's programme for the elimination/control of lymphatic filariasis, dracunculiasis and malaria. Before leaving China, he established the Alice Memorial Hospital, the Hong Kong College of Medicine for Chinese (the forerunner of the University of Hong Kong), and the Hong Kong Medical Society for medical service and education. He also incepted the Hong Kong Dairy Farm for supplying hygienic milk affordable by pregnant women, children and patients.
PubMed: 26038403
DOI: 10.1038/emi.2012.32 -
Asian Pacific Journal of Tropical... Jul 2012Dracunculiasis (Guinea worm disease) is a preventable waterborne parasitic disease that affects the poorest people living in remote rural areas in sub-Saharan African...
Dracunculiasis (Guinea worm disease) is a preventable waterborne parasitic disease that affects the poorest people living in remote rural areas in sub-Saharan African countries, who do not have access to safe drinking water. The Guinea Worm Eradication Program, a 25-year old campaign to rid the world of Guinea Worm disease has now reached its final stage accelerating to zero cases in all endemic countries. During the 19th and 20th centuries, dracunculiasis was common in much of Southern Asia and the African continent. The overall number of cases has been reduced tremendously by ≥99%, from the 3.32 million cases estimated to have occurred in 1986 in Africa to only 1,797 cases reported in 2010 reported in only five countries (Sudan, Mali, Ethiopia, Chad and Ghana) and Asia free of the disease. This achievement is unique in its kind--the only previously eradicated disease is smallpox, a viral infection for which vaccination was possible--and it has been achieved through primary community-based prevention and health education programs. Most efforts need to be taken in two countries, South Sudan (comprising 94% or 1,698 out of 1,797 of the cases reported world-wide in 2010) and Mali because of frequent movements of nomads in a vast area inside and outside Mali's borders. All factors favourable to dracunculiasis eradication are available including adequate financial resources, community and political support and high levels of advocacy. Thus there is no reason that this disabling parasitic disease cannot be eradicated soon before surprises arise such as new civil conflicts in currently endemic countries.
Topics: Africa South of the Sahara; Animals; Disease Eradication; Dracunculiasis; Dracunculus Nematode; Drinking Water; Humans; Incidence; Life Cycle Stages; Physical Therapy Modalities; Water Quality
PubMed: 22647809
DOI: 10.1016/S1995-7645(12)60088-1 -
The American Journal of Tropical... Dec 2020Dracunculiasis, slated for global eradication, typically is acquired by drinking stagnant water containing microscopic crustaceans (copepods) infected with Dracunculus...
Dracunculiasis, slated for global eradication, typically is acquired by drinking stagnant water containing microscopic crustaceans (copepods) infected with Dracunculus medinensis larvae, causing clusters of case persons with worms emerging from the skin. Following a 10-year absence of reported cases, 9-26 sporadic human cases with few epidemiologic links have been reported annually in Chad since 2010; dog infections have also been reported since 2012. We conducted an investigation of human cases in Chad to identify risk factors. We conducted a case-control study using a standardized questionnaire to assess water and aquatic animal consumption, and links to dog infections. Case persons had laboratory-confirmed D. medinensis during 2013-2017. Each case person was matched to one to three controls without history of disease by age, gender, and residency in the village where the case person was likely infected. We estimated odds ratios (ORs) using simple conditional logistic regression. We enrolled 25 case persons with 63 matched controls. Dracunculiasis was associated with consumption of untreated water from hand-dug wells (OR: 13.4; 95% CI: 1.7-108.6), but neither with consumption of aquatic animals nor presence of infected dogs in villages. Unsafe water consumption remains associated with dracunculiasis. Education of populations about consuming safe water and using copepod filters to strain unsafe water should continue and expand, as should efforts to develop and maintain safe drinking water sources. Nevertheless, the peculiar epidemiology in Chad remains incompletely explained. Future studies of dogs might identify other risk factors.
Topics: Adolescent; Adult; Animals; Case-Control Studies; Chad; Child; Child, Preschool; Disease Eradication; Dog Diseases; Dogs; Dracunculiasis; Dracunculus Nematode; Drinking Water; Female; Humans; Infant; Infant, Newborn; Male; Middle Aged; Odds Ratio; Risk Factors; Surveys and Questionnaires; Young Adult
PubMed: 33289475
DOI: 10.4269/ajtmh.20-0584