“In combination with other control measures, WHO strongly recommends treating all water bodies in and around affected areas with temephos – a cyclopicide – to kill water fleas. This worked very well during elimination campaigns in many formerly endemic countries and is well documented.” said Dr Dieudonné Sankara, Team Leader of WHO’s dracunculiasis eradication unit.
The phenomenon of infection in dogs in Chad was noted in 2012. In 2016, more than 1000 dogs were reported with emerging guinea worms. These worms, which are genetically undistinguishable from those emerging in humans, are being detected in the same at-risk area. The transmission dynamics of this unusual epidemiology are being investigated. Adequate surveillance needs to be maintained in countries bordering Chad, particularly Cameroon and the Central African Republic, to prevent any spread of the infection.
Dracunculus medinensis larvae in unsafe drinking water are ingested by water fleas (copepods) before becoming infectious. Anyone consuming unboiled or unfiltered water infested with larvae-ridden copepods will contract the disease.
Besides this unusual epidemiology in dogs, Chad has so far confirmed 3 human cases, all of which were reportedly contained, in Chari Baguirmi Region in Loumia Centre, Mandelia District, Kakale Mberi village, Guelendeng District, and Bougoumene 1 village, Dourbali District.
Since the beginning of this year, Ethiopia and South Sudan (where cases occurred in 2016) have reported zero cases. Mali, which had reported 5 cases in 2015, has not reported any case since 1 January 2016.
The countries which are endemic for dracunculiasis continue to share information with neighbouring countries so as to strengthen cross-border surveil¬lance. Furthermore, due to the scale of population movement arising from conflicts, surveillance has been reinforced in refugee camps in countries bordering either South Sudan or Mali.
The disease
Dracunculiasis is a crippling parasitic disease caused by D. medinensis, a long, thread-like worm. It is usually transmitted when people drink stagnant water contaminated with parasite-infected water fleas.
WHO works with Member States and in partnership with The Carter Center and UNICEF to support efforts to eradicate the disease. WHO provides technical guidance, works with national programmes to coordinate surveillance in dracunculiasis-free areas, and monitors and reports on the progress achieved.
It is the only organization mandated to certify countries as free of transmission of the disease following the recommendations of the International Commission for the Certification of Dracunculiasis Eradication. Since 1995, WHO has certified a total of 198 countries, territories and areas (belonging to 186 Member States) as free of dracunculiasis transmission.