Tungiasis-associated morbidity in pigs and dogs in endemic villages of Uganda

Abstract

BackgroundTunga penetrans (Insecta, Siphonaptera, Tungidae) causes severe morbidity among heavily infected humans and animals in Latin America and sub-Saharan Africa. The clinical pathology of tungiasis in animals has never been studied systematically.MethodsThis was a cross-sectional study conducted between January to March 2015, aimed at describing tungiasis-associated clinical pathology in 121 and 20 T. penetrans-infected pigs and dogs, living in nine and five endemic rural villages respectively located in Bugiri District, Busoga, Uganda.ResultsThe parasite load of infected animals ranged from one to 246 (median 8) and one to eight (median 2) in pigs and dogs, respectively. In pigs 99.3 % and in dogs 100 % of the lesions were located on feet. In pigs, hind legs were significantly more affected than front legs (90.9 % vs. 57.9 %; p = 0.002) and also had more lesions than the front legs (median 5 vs. 1; p = 0.0001). However, in dogs localization of lesions between front and hind legs never differed significantly (front, 50 % vs. hind, 65 %; p = 0.51) and so were the number of lesions (median front = 0.5 vs. median hind = 2; p = 0.7). Acute and chronic clinical pathology coexisted. The most common disease manifestations in pigs were hoof wall erosions (68.6 %), tissue necrosis of hoof wall and skin (66.1), pain at infection sites (47.9 %), hoof deformity (45.5 %), fissures (44.6 %) and edema (44.6 %). In dogs, tungiasis mainly presented with pain at attachment site (80 %), ulcers (55 %), necrosis (30 %) as well as hyperemia and edema (both 15 %). One pig had lost dew claws while two had loose detaching claws. Despite a lower number of sand fleas, a higher proportion of infected dogs (20 %) than pigs (5.8 %) exhibited functional limb use difficulties (p = 0.05).ConclusionsThe pattern of clinical manifestations in pigs and dogs were very similar to those reported from affected humans and rats. The important morbidity associated with animal tungiasis makes the disease a serious veterinary health problem in sub-Saharan Africa warranting treatment and control for optimal animal production.

Canine tungiasis: High prevalence in a tourist region in Bahia state, Brazil

“…Few studies reported the location of the lesions and clinical/behavioral changes in infested dogs. In our study, all positive animals had lesions on their pads, corroborating previous findings of Mutebi et al (2016) from five endemic rural villages in Uganda. However, these authors observed edema and lameness in 15% and 20% of the evaluated dogs, respectively, differing from the finding of our study, with edema and lameness in 95.8% and 4.2% of infected dogs.…”

Control of Tungiasis in Absence of a Roadmap: Grassroots and Global Approaches

“…Tungiasis in livestock is associated with severe morbidity and by consequence reduces the merchantability of affected animals, an additional negative impact on household economics [ 30 , 31 , 32 ]. Thus, there is a vicious cycle between poverty exposing people to tungiasis and tungiasis causing more poverty and ultimately impacting the socioeconomic development of whole communities.…”

Presence of dogs and proximity to a wildlife reserve increase household level risk of tungiasis in Kwale, Kenya

“…Dogs have been implicated as risk factors for human tungiasis in other studies [ 41 , 44 , 57 – 62 ]. Increased numbers of lesions in dogs and cats are associated with more human infestations in Brazil.…”

“…Pigs have been shown to be a major reservoir for T. penetrans in Uganda, Nigeria, Brazil, and other areas [ 31 , 33 , 39 , 40 ]. Tungiasis is common in dogs in many areas around the world [ 41 – 45 ]. Tungiasis cases in humans have also been associated with the presence of specific animal species around the home [ 46 ] and seasonal patterns of tungiasis in humans and animals have been found to overlap [ 47 ].…”