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By the end of 1998, Asia was free of dracunculiasis (Guinea worm disease), with Pakistan, India, and Yemen having interrupted transmission in 1993, 1996, and 1997, respectively. Transmission of the disease was also interrupted in Cameroon and Senegal during 1997. Chad reported only 3 cases during 1998. Dracunculiasis is now confined to only 13 countries in Africa. The overall number of cases has been reduced by more than 97% from the 3.2 million cases estimated to have occurred in 1986 to 78,557 cases reported in 1998. Because the civil war in Sudan remains the major impediment to eradication of dracunculiasis, the interim goal is to stop all transmission outside that country by the end of 2000. The most important operational need now is for national programs to improve the frequency and quality of supervision of village-based health workers in order to enhance the sensitivity of surveillance and effectiveness of case containment.

SummaryThe use of cloth to filter drinking water for guinea worm prevention is a long-standing control strategy and part of a mixed approach that includes the provision of wells, chemical treatment of ponds and protection of water supplies. As the goal of eradication nears, filters are a useful component of the quick response needed to implement case containment at village level. Various designs of filters have been used. Individual hand-sewn filters (HSFs) using monofilament nylon cloth have played a central role in village-based control to date. Problems such as the need to continually reinforce correct habitual filtering behaviour have led to the design and testing of communal filtration units (CFUs) made from metal oil drums with filter cloth inserted in the top and spigots at the bottom. Approximately one year after the introduction of CFUs in the South-western Zone of Nigeria, village surveys were conducted to determine opinions about the two types of filters and reported use. Percentage use was calculated by dividing the number of times water was filtered in the week preceding the survey by the number of times water was collected in that week. Those respondents with access to CFUs filtered an average of 91.9% of the time compared to 75.7% of those with HSFs. Using the village as level of analysis since it was the main level of intervention, the average percent of times villagers in CFU villages filtered was 91.1% compared to 77.8% in HSF villages. Although CFUs were more expensive in the short run, their greater acceptance by villagers is a factor to recommend their wider implementation to speed up elimination of guinea worm from Nigeria.

The serum antibody responses (specific IgG1, IgG4, and IgE, and total IgE) to Dracunculus medinensis infection in humans from a highly endemic area of northern Ghana were examined regularly by ELISA over a period of one year in cohorts of individuals who developed a patent D. medinensis infection during the study period (actively infected category), or who claimed to have never had a patent infection (endemic normal category). The results were analyzed in relation to seasonality and time of patency of infection. For individuals in the actively infected category, a clear seasonal variation in the mean levels of specific IgG1 and IgG4 was found, with the highest levels late in the dry season and early in the rainy season, when transmission is high, and the lowest levels late in the rainy season and early in the dry season. Endemic normal individuals responded with low and fluctuating levels of specific IgG1 and with low and nonfluctuating levels of specific IgG4. For specific and total IgE, no seasonal variation was observed in any of the two infection status categories. In relation to time of patency of infection (only involving the category of actively infected individuals), the mean levels of specific IgG1 and IgG4 increased from two months before patency of infection, peaked during patency, and then gradually decreased for four months until a constant level was reached. No significant fluctuations in the levels of specific and total IgE were observed in relation to time of patency. The present study thus showed extensive variation in levels of D. medinensis-specific IgG1 and IgG4 (but not IgE) over time. Seasonal variations in antibody responses may also occur in other helminth infections, especially those with seasonal transmission, and these should be taken into consideration when interpreting the results of immunologic studies.

Infections with Dracunculus medinensis frequently occur in the same geographical area as infections with Onchocerca volvulus and Wuchereria bancrofti . This study analysed the significance of D. medinensis infections for the specificity and sensitivity of available tests for antibody-based diagnosis of onchocerciasis (using individual recombinant clones OV-10, OV-11 and OV-16, and the OV-7/OV-10/OV-16 tri-cocktail, in an enzyme-linked immunosorbent assay) and for circulating antigen-based diagnosis of bancroftian filariasis (using the TroBio ™ and the ICT ™ card tests). Some immunological cross-reactivity was observed with all tests. When using individual recombinant O. volvulus antigens, the highest assay indices were obtained for clone OV-10, and the lowest for clone OV-16. Testing the serum responses against the tri-cocktail of recombinant antigens did not notably improve the assay indices. Two of 40 serum samples from individuals with patent dracunculiasis gave a false positive response in the ICT ™ test and one of these was also positive in the TropBio ™ test. Possible implications of applying these diagnostic assays in areas endemic for dracunculiasis are discussed.

To explore the possibility for development of an immunodiagnostic test for Dracunculus medinensis infections, the antibody responses (IgG1, IgG2, IgG3, IgG4 and IgE) to antigen preparations made from adult female worms (ADGW) and first stage larvae (LVGW) of D. medinensis were analysed. By sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE)/Western blotting, sera from individuals with patent D. medinensis infection reacted extensively and similarly with ADGW and LVGW over a broad molecular weight range (5-200 kDa). Sera from individuals infected with Onchocerca volvulus (the major cross-reacting infection) had a more pronounced reaction with ADGW than LVGW, and only with antigens of molecular weights above 23 kDa. These findings were used to design an enzyme-linked immunosorbent assay (ELISA) with high sensitivity and specificity for D. medinensis infection. The most promising results were obtained when detecting for specific IgG4. Thus, when using LVGW, the assay had a sensitivity of 83% and a specificity of 97%. Refining the antigen into a low molecular weight filtrate improved the sensitivity to 92%, and the sensitivity was further improved (to 96%) when combining the results from two or more antibody types measured simultaneously, without affecting the specificity. The results were encouraging for the prospects for developing an applicable immunodiagnostic test for patent D. medinensis infections based on detection of specific serum antibodies.

Dracunculiasis is rarely reported in cats, yet over the last few years we have identified two cats with filarioid-like spirurid infections. Case 1 was a 9-year-old cat with pituitary-dependent hyperadrenocorticism from New York tate from which four adult dracunculoid nematodes were isolated from its torso. Based on morphometric characteristics and parasite geographic distribution, the specimens were identified as Dracunculus insignis females; at least one of the females was gravid, suggestive of patent infection. Species identification was confirmed through amplification and sequence analysis of nuclear and mitochondrial loci. Case 2 was a 14-year-old diabetic cat from Massachusetts. Formalin-fixed sections were obtained from a subcutaneous mass excised from the left foreleg. Histopathological examination revealed a large nematode with morphometrical characteristics of Dracunculus, surrounded by lymphocytes and sheets of eosinophils. These two cases appear to be the first published reports of dracunculiasis in domestic cats in the USA, and based on the findings from case 1, D insignis may be the species associated with both infections.

There are a number of nematode infections that rarely involve the central nervous system. Ascaris lumbricoides and the pig nematode A. suum have been associated with encephalitis. Adult Dracunculus medinensis may invade the spinal cord resulting in epidural abscess and paralysis. Lagochiloascaris spp. are free-living nematodes reported mainly in Brazil. Lagochiloascaris minor infection may cause diseases of the head and neck and the central nervous system. Halicephalobus (Micronema) parasitizes horses and may also involve the human central nervous system.

After 30 years of control campaigns, guinea worm faces eradication. However, dogs are expected to thwart the eradication of dracunculiasis as they act as alternative hosts of the worm. The health community un doubtedly have to recognise the success of the Guinea Worm Eradication Program (GWEP), although some flaws cannot be overlooked. One of the most essential points when trying to achieve the control of parasitic infections is to determine the role of reservoirs that could maintain the disease. Erroneously, dogs are likely to have been ignored as reservoirs of Dracunculus medinensis so far. I fi nd it hard to believe that a parasite that has always been considered specific to humans is able to adapt perfectly to a supposedly new host in such a short period of time. The considerable increase in the number of infected dogs detected in Chad in 2015 has led to the assertion that there was a “mysterious epidemic” of dracunculiasis in that country. On the contrary, I believe that the reward off ered since February, 2015, (US$20) for reporting infected dogs in Chad has provoked the increase in the detection of parasitised dogs from that month onwards. Before trying to analyse the peculiar epidemiology of dracunculiasis in Chad, experts should consider that these results are likely to be the direct consequence of this incentive in such a poor country, where the monthly minimum wage is around $110. Several other factors should also be considered. First, it seems that the only information available about the presence of guinea worms in dogs came from people living in villages along the Chari River. Apparently, locals cannot recall there being infected dogs in the past. Is that level of reporting reliable enough? Second, dogs, supposedly, become infected by eating the entrails of fi sh with dracunculus larvae. However, these larvae have not been found in any potential paratenic hosts (fi sh, frogs, or lizards). Third, in August, 2014, and 2015, the larvicide temephos was applied to specifi c sections of lagoons where dogs usually drink. This measure was probably taken too late. The infected dogs detected in 2015 probably became infected before the use of the larvicide, considering the long incubation period of D medinensis. These factors notwithstanding, the continued presence of guinea worms in dogs does not mean that the parasite cannot be expected to disappear in humans if they continue to drink safe water.

Dracunculiasis (Guinea worm disease) is caused by Dracunculus medinensis, a parasitic worm. Approximately 1 year after initial infection from contaminated drinking water, the worm emerges through the skin of the infected person, usually on the lower limb. Pain and secondary bacterial wound infection can cause temporary or permanent disability that disrupts work and schooling for the entire family. In 1986, the World Health Assembly (WHA) called for dracunculiasis elimination and the Guinea Worm Eradication Program, supported by The Carter Center, World Health Organization (WHO), United Nations Children's Fund (UNICEF), CDC, and other partners, was coalesced to assist ministries of health of endemic countries in meeting this goal. At that time, an estimated 3.5 million cases occurred annually in 20 countries in Africa and Asia. This report updates published and previously unpublished surveillance data reported by ministries of health and describes progress toward global dracunculiasis eradication. In 2011, a total of 1,058 cases were reported. As of 2012, dracunculiasis remained endemic in only four countries. Through June 2012, worldwide reductions in reported cases continued, compared with the first 6 months of 2011. Failures in surveillance and containment, lack of clean drinking water, and insecurity in Mali and parts of South Sudan continue to challenge dracunculiasis eradication efforts.

SummaryFor centuries, the Guinea worm parasite (Dracunculus medinensis) has caused disabling misery, infecting people who drink stagnant water contaminated with the worm's larvae. In 2012, there were 542 cases of Guinea worm reported globally, of which 521 (96.1%) were reported in South Sudan. Protracted civil wars, an inadequate workforce, neglect of potable water provision programs, suboptimal Guinea worm surveillance and case containment, and fragmented health systems account for many of the structural and operational factors encumbering South Sudan's Guinea worm eradication efforts. This article reviews the impacts of six established Guinea worm control strategies in South Sudan: (1) surveillance to determine actual caseload distribution and trends in response to control measures; (2) educating community members from whom worms are emerging to avoid immersing affected parts in sources of drinking water; (3) filtering potentially contaminated drinking water using cloth filters or filtered drinking straws; (4) treating potentially contaminated surface water with the copepod larvicide temephos (Abate); (5) providing safe drinking water from boreholes or hand-dug wells; and (6) containment of transmission through voluntary isolation of each patient to prevent contamination of drinking water sources, provision of first aid, and manual extraction of the worm. Surveillance, community education, potable water provision, and case containment remain weak facets of the program. Abate pesticide is not a viable option for Guinea worm control in South Sudan. In light of current case detection and containment trends, as well as capacity building efforts for Guinea worm eradication, South Sudan is more likely to eradicate Guinea worm by 2020, rather than by 2015. The author highlights areas in which substantial improvements are required in South Sudan's Guinea worm eradication program, and suggests improvement strategies.

The long time needed for global eradication of dracunculiasis (Guinea worm disease) was not anticipated at the outset. The successful eradication of smallpox in 10 years compares with the target date set in 1985 for dracunculiasis eradication - 1995. Seventeen years after that date, transmission continues. Why? Various factors are responsible, mainly lack of resources, or resources ineffectively used. The example of Ghana, where the programme stagnated for a decade, sheds light on this delay. When more resources were put into Ghana's programme in 2007, transmission of the disease was interrupted in 3 years. The variable success of dracunculiasis eradication in different countries provides lessons for future disease eradication programmes.

In 1986, the World Health Assembly (WHA) called for the elimination of dracunculiasis (Guinea worm disease), a parasitic infection in humans caused by Dracunculus medinensis. At the time, an estimated 3.5 million cases were occurring annually in 20 countries in Africa and Asia, and 120 million persons were at risk for the disease. Because of slow mobilization in countries with endemic disease, the 1991 WHA goal to eradicate dracunculiasis globally by 1995 was not achieved. In 2004, WHA established a new target date of 2009 for global eradication; despite considerable progress, that target date also was not met. This report updates published and previously unpublished data and describes progress towards global eradication of dracunculiasis since January 2010. The number of indigenous cases of dracunculiasis worldwide decreased 44%, from 3,185 cases in 2009 to 1,793 in 2010. As of June 2011, dracunculiasis remained endemic in three countries (Ethiopia, Mali, and South Sudan). Of the 814 cases that occurred during January-June 2011, a total of 801 (98%) were reported from 358 villages in South Sudan. By October 2010, Ghana had gone 12 months without an indigenous case, thereby interrupting transmission; Ethiopia and Mali are close to interrupting transmission, as indicated by the small and declining numbers of cases in these two countries. An outbreak of 10 cases was discovered in Chad in 2010. The current target is to interrupt transmission in the remaining countries as soon as possible. Insecurity (e.g., sporadic violence or civil unrest) in areas of South Sudan and Mali, where dracunculiasis is endemic, poses the greatest threat to the success of the global dracunculiasis eradication campaign.

Transmission of dracunculiasis (Guinea worm disease), a waterborne, parasitic disease targeted for eradication, was thought to have been interrupted in Chad since 2000, when the last case was reported. However, in 2010, 10 cases were confirmed by the Chad Ministry of Public Health (Ministère de la Santé Publique [MSP]) and the World Health Organization (WHO) during field investigations in which rumored cases were investigated and nearby villages were actively searched for additional cases. Because patients were not prevented from contaminating water sources, new cases were expected in 2011. During January-February 2011, MSP, WHO, and CDC conducted an investigation to gather additional information to guide prevention and response activities before the 2011 transmission season. Seven districts where cases had been confirmed or suspected in 2010 or where dracunculiasis was endemic during 1994-2000 were surveyed. The results of those surveys indicated that residents of 116 (55%) of 210 villages and 13 (87%) of 15 nomad camps consumed water from unsafe sources; 157 (75%) of 209 village key informants (KIs) and five (33%) of 15 nomad camp KIs knew about dracunculiasis. Thirty-one villages had confirmed or suspected cases during 2009-2011 and were classified as at-risk, requiring weekly active surveillance and urgent pre-positioning of materials for the 2011 transmission season. Nomadic populations are at risk for dracunculiasis because of unsafe water consumption and minimal knowledge of the disease. These populations also require targeted surveillance and prevention efforts (e.g., filter distribution, education, and case containment) to interrupt dracunculiasis transmission .

Dracunculiasis currently occurs in only 5 countries, Nigeria inclusive.To study the prevalence and management of the guinea worm disease at the threshold of its eradication in Oyo state.KAP questionnaires were administered to head of households and cyclopoid copepods in domestic water sources were identified and checked for infection. Prevalence of infection in the study population was monitored and reasons for continued transmission in the area ascertained.Fifty three cases were reported in study area in 2004 and 2005 but no cases in 2006. Five hundred head of households were interviewed in ten villages. 43.9% believe the disease is in the blood and further probing shows that 54.6% believe infection is due to inherited susceptibility. 1.8% used antibiotics for treatment while 37.1% used herbs. Boreholes, wells, treatment of ponds with Abate™, filter distribution and health education were interventions in place. Un-infected Halicyclops korodiensis and Africyclops curticornis were recovered from ponds.Ignorance especially belief in inherited susceptibility, lack of sustained safe water sources and influx of infected immigrant farmers are major variables responsible for the continued presence of the disease in the state.

The serum antibody response (total, and isotypes IgG1, IgG4, IgM, IgA and IgE) to Guinea worm infection was examined in humans from a highly endemic area of northern Ghana by ELISA and SDSPAGE/Western blot techniques using an adultD. medinensisantigen. Sera were obtained early and late in the peak transmission period, from persons with patent and postpatent infections, as well as from persons from the same endemic area who claimed never to have had Guinea worm infection. To observe for potential cross-reactions in the tests, sera were also obtained from areas with no transmission of Guinea worm from patients with hookworm.O. volvulusandW. bancroftiinfections, and from non-infected controls. Sera from persons living in the Guinea worm endemic area reacted extensively with Guinea worm antigen in both tests, and large numbers of bands were produced in the Western blots (up to 35 identified for some sera). For most antibody isotypes, the ELISA absorbance values obtained with sera from the same individuals varied between the two transmission seasons, with the highest titres present towards the end of the peak transmission period. The mean antibody titres for persons in the patent and postpatent infection categories were not significantly different when sera were obtained at the same season of the year. Persons from the endemic area, who claimed never to experience patent infections, also had antibodies to Guinea worm, although at significantly lower mean levels than for the patent and postpatent categories. The highest specificity in the ELISA and the most homogenous Western blots were obtained when detecting for antibodies of the IgG4isotype.

We describe 11 cases of suspected Dracunculus medinensis infection in which the worm recovered was identified as Onchocerca volvulus. Identification was based on morphology of the examined specimen.

Introduction of the host is the main reason behind introduction of the parasite, e. g., nematodes. The introduction of the Japanese eel (Anguilla japonica) in Europe in the 1980s resulted in expansion of the swimbladder nematode Anguillicola crassus which soon invaded not only populations of the European eel (A. anguilla), but also other local fish. The raccoon (Procyon lotor) is native to North America. It is the specific host of Strongyloides procyonis and Baylisascaris procyonis. More than 90 species of wild and domestical bird and mammal species, including humans, have been infected with B. procyonis larvae. The larvae enter various organs of paratenic hosts, particularly the central nervous system and eye, causing severe diseases and death. Asthworthius sidemi--a blood-succking, abomasal nematode, a specific parasite of the Asiatic sika deer (Cervus nippon) and sambar deer (C. unicolor)--was first introduced with its hosts into countries adjacent to Poland. A. sidemi is especially dangerous to the European bison (Bison bonasus) which is its new host. The bison populations, in both Białowieza Primaeval Forest and the Bieszczady Mts, sometimes show a 100% prevalence and mass infection intensity. Imported animals, sold in pet shops or available from private breeding firms, often carry non-native parasites. For example, the red-eared tortoise (Trachemys scripta elegans) and Afgan tortoise (Agrionemys horsfieldii) carry nematodes Angusticaecum holopterum, Tachygonetria lobata and T. robusta. Migratory birds in their wintering grounds are often infected with parasites which are usually not constant components of the native fauna, but sometimes nematodes could find a suitable conditions to complete their life cycle. E.g. Cyathosoma microspiculum, species specific to cormorants (Phalacrocorax carbo) and previously recorded only from Asia and the Asian-European boudary, was able complete the life cycle in Poland. The increasingly frequent travels to countries with different climatic conditions contribute to introduction of non-native nematodes: Dirofilaria immitis--in dogs, D. repens or Ancylostoma brasiliense--in humans.

Dracunculiasis is a parasitic infection caused by Dracunculus medinensis. Persons become infected by drinking water from stagnant sources (e.g., ponds) contaminated by copepods (water fleas) that contain immature forms of the parasite. In 1986, the World Health Assembly (WHA) called for the eradication of dracunculiasis (Guinea worm disease) at a time when an estimated 3.5 million cases occurred annually in 20 countries in Africa and Asia and 120 million persons were at risk for the disease. Because of slow mobilization in countries with endemic disease, the global dracunculiasis eradication program did not meet the 1995 target date for eradicating dracunculiasis set by WHA in 1991. In 2004, WHA established a new target date of 2009 ; despite considerable progress toward global eradication, that target date also will not be met. This report updates continued progress toward global eradication of dracunculiasis since January 2008. At the end of December 2008, dracunculiasis was endemic in six countries (Ethiopia, Ghana, Mali, Niger, Nigeria, and Sudan). The number of indigenous cases of dracunculiasis had decreased 52%, from 9,585 in 2007 to 4,619 in 2008. Of the 1,446 cases that occurred during January-June 2009, 1,413 (98%) were reported from Sudan and Ghana. Currently, insecurity (e.g., sporadic violence or civil unrest) in areas of Sudan and Mali where dracunculiasis is endemic poses the greatest threat to the success of the global dracunculiasis eradication program.

In 2006, Ghana ranked second in Guinea worm disease (GWD) incidence and reported a previously undocumented 20% prevalence of worm breakage. A prospective study was conducted in 2007 to validate and describe worm breakage and determinants. Among 221 patients with known outcomes, the worm breakage rate observed was 46%. After controlling for demographics, worm and wound presentation, and treatment course and provision, worm breakage was associated with narrow-diameter worms (2 mm) (adjusted odds ratio [AOR] 2.79; 95% confidence interval [CI] = 1.03-7.53). Protective factors against worm breakage included antibiotic ointment use (AOR 0.31; 95% CI = 0.14-0.70), bandage protocol compliance (AOR: 0.38; 95% CI = 0.16-0.89), intact bandages (AOR 0.27; 95% CI = 0.09-0.82), and bloody compared with dry wounds (AOR 0.09; 95% CI = 0.01-0.7). The high worm breakage rate observed warrants improvement in case management and patient care. Adherence to established treatment protocols should be facilitated through improved provider training and supervision to reduce the disabling consequences of broken worms.

We report one case of endomyocardial fibrosis with a relapsing pericarditis, associated with an aberrant migration of Dracunculus medinensis in the pericardium, in a 22-year-old patient from an endemic zone of bilharziasis and dracunculosis in Côte d'Ivoire. The evolution has been marked by the appearance of thrombus in the right atrium. The patient died on the 49th day of hospitalization following an refractory cardiac insufficiency.

Studies of the relative importance of different copepod species in areas of endemic dracunculiasis have been restricted, in part, by limited access to Dracunculus medinensis. However, development of the D. insignis-ferret model provides a source of larvae of a species closely related to D. medinensis. Using larvae derived from this model, the susceptibility of four species of copepods from D. medinensis-endemic areas was compared to that of Canadian Acanthocyclops vernalis, which is fully susceptible to D. insignis. Cryptocyclops linjanticus, from Cameroon, was susceptible but highly sensitive to infection, resulting in high mortality. Mesocyclops aequatorialis similis, also from Cameroon, was fully susceptible, but M. leuckarti leuckarti from Pakistan was partially refractory to D. insignis, as was Thermocyclops emini from Cameroon. Comparisons of infection rates and mean and maximum larval recoveries at three to four and 16-20 days after infection indicated that exposure to 15 first-stage larvae exceeded the threshold of tolerance of A. vernalis, C. linjanticus and M. a. similis to infection with D. insignis. This may account for a decreased survival rate in these copepods which is not evident in the partially refractory T. emini and M. l. leuckarti. The patterns of susceptibility of these copepods to D. insignis are the same as those of copepods exposed to D. medinensis, and indicate that D. insignis can be used to examine factors influencing the susceptibility of copepods to dracunculid infection.

The Falcon assay screening test-enzyme-linked immunosorbent assay (FAST-ELISA) and the enzyme-linked immunoelectrotransfer blot (EITB) technique were used to test human sera with Dracunculus medinensis adult worm antigen in order to assess their potential value in the immunodiagnosis of dracunculiasis. The human sera used were from patients with prepatent and patent D. medinensis infections or from patients infected with other nematodes (Onchocerca volvulus and Loa loa) or trematodes (Schistosoma mansoni and S. haematobium), as well as uninfected Nigerian and Puerto Rican normal controls. In the FAST-ELISA, the sera from prepatent and patent dracunculiasis patients gave the highest absorbance values relative to normal human sera. The highest cross-reactivity was observed with onchocerciasis sera; no cross-reactivity was seen with sera from individuals with loiasis or schistosomiasis mansoni or haematobia. By the EITB, sera from dracunculiasis patients specifically recognized a 16 kDa protein (Dm 16) and antibodies to Dm 16 disappeared 2 months after worm extraction. Recognition of Dm 16 occurred from the late prepatent stage. A 17 kDa protein (Dm 17) was also recognized by dracunculiasis sera, but antibodies to Dm 17 disappeared more slowly and were present 1 year after recovery. The 16 kDa and 17 kDa antigens of D. medinensis may be useful in the immunodiagnosis of dracunculiasis.

Immunoelectroblotting and enzyme-linked immunosorbent assay were used to identify non-cross-reacting antigenic components of Dracunculus medinensis and the filarial worms Onchocerca volvulus, Loa loa, Wuchereria bancrofti, Brugia malayi, and Mansonella ozzardi. Parasite specific serodiagnostic ELISA systems for onchocerciasis and dracunculiasis were devised based on these findings. Phosphate buffered saline extracts of adult worms were passed through a column of monoclonal antibodies to phosphorylcholine (PC). Crude and PC-depleted extracts were reacted on ELISA plates with individual sera from subjects infected with a range of nematodes. Binding of total antibody (Ig) or IgG class antibody and IgG4 subclass antibody was revealed using goat antihuman-Ig-phosphatase conjugate, or appropriate mouse monoclonal antihuman-Ig-type-specific reagents, followed by goat antimouse-Ig-phosphatase conjugate. Specificity of ELISA was improved by restricting reaction to the host's IgG4 antibody subclass, and/or by removing PC determinants from crude antigens. In parallel immunoelectroblots, crude and PC-depleted extracts probed with pooled sera showed potentially useful diagnostic antigens, including a 12 kDa protein from D. medinensis and 14, 18, and 27 kDa proteins from O. volvulus. Two Onchocerca specific ELISA systems non-reactive with antibodies to D. medinensis were devised.

Dracunculus medinensis better known as guinea worm is the longest nematode infecting humans. Mature female worms migrate along subcutaneous tissue to reach the skin below the knee forming a painful ulcerating blister. Calcified male worm can occasionally be found in the retro peritoneum. Finding of a calcified worm in the breast tissue is very rare. We report a case of a fit and well African lady who was found to have a calcified guinea worm in the breast on a mammographic examination for investigation of a breast lump.A 51 years old female, presented in the surgical outpatient clinic with a painless irregular lump under the right nipple on clinical examination. There were no skin changes, nipple discharge or axillary lymphadenopathy. Mammogram showed a calcified Guinea worm.No treatment was offered and a repeat mammogram after one year showed the same findings. She was discharged from the clinic without any follow up and will be screened routinely as per national guidelinesGuinea worm can be included in the differential diagnosis of the breast lump especially in the endemic areas although the finding remains very rare.

Thanks to a two-decade campaign, guinea worm disease is about to be eradicated without any drug therapy or vaccine. Dr. Michele Barry writes that its demise will be proof that people can be persuaded to change their behavior through innovative health education. Former President Jimmy Carter and Dr. Donald Hopkins, vice president for health programs at the Carter Center, discuss the strategy they have pursued in mobilizing poor village communities to help eradicate guinea worm disease worldwide.

Having begun its national Guinea Worm Eradication Program (UGWEP) in 1991 (1991 population, 16.6 million) with the third-highest number of cases reported by any endemic country, and ranked as the second-highest endemic country in the world in 1993, by 2004, Uganda celebrated its first full calendar year with no indigenous cases of the disease. Systematic interventions began in 1992 and were gradually intensified until the final indigenous case occurred in July 2003. The favorable concentration of most cases in relatively few northern districts of the country was partly offset by chronic insecurity in much of the endemic area and by repeated importations of cases from neighboring Sudan. Strong support and dedicated leadership by government officials and external partners were keys to this program's dramatic success. This program cost approximately US dollar 5.6 million.

Since the seminal review by Ralph Muller about Dracunculus and dracunculiasis in this serial publication in 1971, the Centers for Disease Control and Prevention and The Carter Center forged, during the 1980s, a coalition of organizations to support a campaign to eradicate dracunculiasis. Eighteen of 20 countries were known in 1986 to have endemic dracunculiasis, i.e., Benin, Burkina Faso, Cameroon, Chad, Côte d'Ivoire, Ethiopia, Ghana, India, Kenya, Mali, Mauritania, Niger, Nigeria, Pakistan, Senegal, Sudan, Togo, and Uganda. Transmission of the disease in Yemen was documented in 1995, and the World Health Organization (WHO) declared Central African Republic endemic in 1995. As of the end of 2004, a total of 16026 cases of dracunculiasis were reported from 12 endemic countries (91% of these cases were reported from Ghana and Sudan, combined), a reduction greater than 99% from the 3.5 million cases of dracunculiasis estimated in 1986 to occur annually; the number of endemic villages has been reduced by91%, from the 23475 endemic villages in 1991; disease transmission has been interrupted in 9 of the 20 endemic countries; and WHO has certified 168 countries free of dracunculiasis, including Pakistan (1996), India (2000), Senegal and Yemen (2004). Asia is now free of dracunculiasis.

Dracunculiasis is a promising candidate for eradication, but transmission of Dracunculus medinensis and recrudescence of the disease have been observed repeatedly. In the present investigation, the D. medinensis-specific cellular cytokine response profiles and the parasite-specific antibody subclass reactivity were evaluated in dracunculiasis patients at distinct states of infection. Analysis of the cellular cytokine response in dracunculiasis patients disclosed a D. medinensis antigen-specific depression of IFN-gamma production with patent D. medinensis infection, while the T helper type 2 cytokine IL-10 was similar in patent, post-patent and control individuals, and IL-5 production was always the highest in controls. In parallel, diminished IFN-gamma and IL-12 responses to antigens from Ascaris lumbricoides, Entamoeba histolytica and mycobacteria were observed in patent and post-patent dracunculiasis cases. The parasite-specific IgG(1) and IgG(4) subclass reactivity profiles corresponded with the D. medinensis infection state, and a clear distinction between patent and post-patent patients and controls was found. Overall a depressed cytokine release was observed with patent D. medinensis, which extended beyond the parasite-specific immune responsiveness. The detection of D. medinensis-specific IgG(1) and IgG(4) isotypes may help to distinguish newly exposed, patent and post-patent D. medinensis infections.

This study, undertaken as a component of the global Dracunculiasis Eradication Program (DEP), was designed to provide molecular tools to distinguish Dracunculus medinensis, the nematode causing human dracunculiasis, from other tissue-dwelling nematodes, including other Dracunculus species that infect humans and other animals. DNA was extracted from D. medinensis and from a closely related species that infects North American carnivores, D. insignis, so that the genes coding for the small-subunit ribosomal RNA (18S rRNA) of the parasites could be amplified, sequenced and compared. Sequences were obtained for 20 specimens of D. medinensis (from humans in Pakistan, Yemen and six African countries endemic for dracunculiasis) and three of D. insignis (from raccoons trapped in the state of Georgia in the southern U.S.A.). All of the D. medinensis 18S-rRNA sequences were found to be 1819 bases long and identical. The three D. insignis 18S-rRNA sequences were also found to be identical to each other but were 1821 bases long and differed from the D. medinensis 18S- rRNA sequence at eight positions (representing a difference of 0.44%). The 18S-rRNA coding region of a Guinea worm extracted from a dog in Ghana was indistinguishable from that of the D. medinensis isolates from human cases. These results provide the basis for the molecular differentiation of D. medinensis that will permit the DEP to determine, rapidly and accurately, whether a worm recovered from an area considered dracunculiasis-free is a specimen of D. medinensis or not.

Of the 1,200 people surveyed for dracontiasis in Ribi and Kanje villages in Awe Local Government Area of Plateau State, Nigeria, 982 (82%) were infected. Most infections (98%) involved the lower limb. Worms emerging from the umbilicus, groin, palm, wrist, and upper arm were also encountered. Of the 982 infected persons 206 (21%) were totally incapacitated, 193 (20%) were seriously disabled, and 431 (44%) suffered mild incapacity, while 152 (16%) were unaffected. Of the 5 species of cyclopoid copepods found in their main water source, only Thermocyclops nigerianus and Mesocyclops aequatorialis harboured guineaworm larvae.

Dracunculus medinensis recovered from infected humans were examined for the occurrence and localization of human serum albumin and immunoglobulins. Immunoelectrophoretic examination of homogenates prepared from adult female worms (ADGW) and first stage larvae (LVGW) showed that anti-human albumin antibodies reacted to both stages of the parasite. By direct fluorescence antibody technique, antigens resembling human albumin and human immunoglobulins (isotype IgG) were identified on the surface of adult female worms. The occurrence of host-like compounds on the parasites may be an adaptation for survival of the parasites. A possible interference of these compounds should be considered in attempts to develop methods for immunological diagnosis of D. medinensis infections.

An 11-year-old 13-kg (28.6-lb) spayed female Cocker Spaniel was examined because of subcutaneous nodules on the hind limbs and ventral aspects of the thorax and abdomen. Focal areas of erythema and pyoderma were associated with the nodules, and purulent exudate could be expressed from a fistula in the nodules. A nematode approximately 20.5 cm in length was isolated from a draining fistula in 1 nodule and identified as Dracunculus insignis. The dog was treated with ivermectin, fenbendazole, and metronidazole, but the owner was still able to recover worms from multiple nodules for the next year.

The specific serum IgG1, IgG4, and IgE responses to Dracunculus medinensis and the level of total IgE of individuals living in a highly endemic area of northern Ghana were measured by ELISA. Sera were obtained in the high transmission season from individuals with prepatent, patent, or postpatent infection as well as from individuals from the same endemic area who claimed to have never had a patent infection (i.e., endemic normal individuals). Individuals with prepatent or postpatent infections responded with a significantly lower mean level of specific IgG1 and IgG4 compared with individuals with a patent infection, and with a significantly higher mean level of specific IgG1 and IgG4 compared with endemic normal individuals. For specific IgE, no differences were found in the mean antibody level between the infection status categories. Individuals with a patent infection had a significantly lower mean serum level of total IgE compared with prepatent, postpatent, and endemic normal individuals. Endemic normal individuals had the highest mean level of total IgE. Furthermore, in all clinical categories, high responders for specific IgG1 and IgG4 generally had low levels of total IgE, whereas low responders for specific IgG1 and IgG4 generally had high levels of total IgE. A similar dichotomy, although less distinct, was observed between specific IgG1 and IgG4 on the one hand and specific IgE on the other. Thus, similar to what has been suggested for schistosomiasis and lymphatic filariasis, the relationship between the IgG subclasses and IgE appears to play a role in, or at least to reflect, a mechanism for protective immunity in dracunculiasis.