Molecular identification of hookworm species in dog faeces from Morogoro, Tanzania

Four species of ancylostomatids are considered as canine hookworms, Ancylostoma caninum, A. braziliense, A. ceylanicum and Uncinaria stenocephala. Despite their veterinary relevance, they are zoonotic and able to cause different clinical manifestations and patent infections in humans. Little is known about the hookworm species present in Africa and their distribution. Consequently the main objective of this thesis was to identify, by the use of molecular techniques, the hookworm species present Abstract in canine faecal samples from Morogoro, Tanzania. A second (and minor) objective was to identify gastrointestinal helminth infections in the collected samples by copromicroscopy. The fieldwork was based in Sokoine University of Agriculture (SUA), Morogoro, Tanzania where faecal samples from 160 dogs were collected in four different areas. Hookworm positive samples were processed in order to recover larvae for further molecular characterisation. The molecular work took place at University of Copenhagen, Denmark where 68 samples brought from Morogoro were analyzed. Two different molecular approaches were used PCR-RFLP and newly designed species-specific primers coupled with sequencing. Three different species of gastrointestinal helminths were found. Hookworms were present in 58% of the samples followed by Toxocara spp (6%) and Dipylidium caninum (1%). The species and proportions found by copromicroscopy were in line with previous prevalence reports. By the use of PCR-RFLP we were only able to detect the presence of the ubiquitous A. caninum. However, by sequencing some of the species-specific PCR positive we successfully identify A. braziliense, U. stenocephala and A. ceylanicum. This is the first study, to my knowledge, documenting the presence of the zoonotic A. ceylanicum and U. stenocephala by molecular characterisation in Africa.