The prevalence of Serpulina pilosicoli in humans and domestic animals in the Eastern Highlands of Papua New Guinea

Abstract

SUMMARYIn a survey of five villages in the Eastern Highlands of Papua New Guinea, Serpulina pilosicoli was isolated from rectal swabs from 113 of 496 individuals (22n8 %). Colonization rates ranged from 22n6-30n1 % in four of the villages but was only 8n6 % in the other village. In comparison colonization was demonstrated in only 5 of 54 indigenous people (9n3 %) and none of 76 nonindigenous people living in an urban environment in the same region. Colonization did not relate to reported occurrence of diarrhoea, age, sex, or length of time resident in a village. A second set of 94 faecal specimens was collected from 1 village 6 weeks after the first set. S. pilosicoli was isolated from 27 of 29 individuals (93n1 %) who were positive on the first sampling and from 7 of 65 individuals (10n8 %) who previously were negative. In this case, isolates were significantly more common in watery stools than in normal stools. The annual incidence of infection in the village was calculated as 93n6 %, with an average duration of infection of 117 days. S. pilosicoli could not be isolated from any village pig (n l 126) despite its confirmed presence in 17 of 50 commercial pigs (34n0 %) sampled at a local piggery. Four of 76 village dogs (5n3 %) and 1 of 2 village ducks were colonized with S. pilosicoli, suggesting the possibility of cross transmission between humans and animals.

Comparison of prevalence and risk factors for faecal carriage of the intestinal spirochaetes Brachyspira aalborgi and Brachyspira pilosicoli in four Australian populations

“…Again, colonization was restricted to the Aboriginal and migrant groups, but with the apparent prevalence of faecal shedding increased to levels more consistent with that previously described in Aboriginal children in a remote rural community in WA (33 %) [12], and to those of villagers in Papua New Guinea (23 %) [9], India (25 %) [11], and Bali, Indonesia (12 %) [10]. Apart from the presence of B. aalborgi, which was significantly associated with the presence of B. pilosicoli in both population groups, and in the previous study from India [11], the new analysis did not strengthen the identification of significant risk factors.…”

“…It is usually detected by polymerase chain reaction (PCR) or gene probe assays, and has only occasionally been isolated [5][6][7]. B. pilosicoli is easier to isolate, and has been cultured from faeces in several developing countries [8][9][10][11], from Australian Aborigines [12,13], migrants to Australia from developing countries [13] and homosexual males [14]. Prevalence rates for B. pilosicoli in the faeces of these populations vary from y10 to 50%.…”

Colonization and risk factors for Brachyspira aalborgi and Brachyspira pilosicoli in humans and dogs on tea estates in Assam, India

“…7%) [8], Papua New Guinea (22 . 8 %) [9], and in Aboriginals in a community in the remote north of Western Australia (32 . 6 %) [10].…”

“…The low prevalence in dogs in that study, as in the present study, suggests that they are unlikely to be a significant reservoir of B. pilosicoli infection for humans in developing communities. Indeed, in such settings, it is likely that dogs become colonized with B. pilosicoli following consumption of contaminated human faeces [9,36].…”

“…It has been shown to colonize approximately 30 % of individuals in developing countries including Oman [8] and Papua New Guinea [9], and, in developed countries, occurs at a similarly high prevalence in Aboriginal people in Australia [10], male homosexuals [3] and patients infected with human immunodeficiency virus (HIV) [11]. By comparison, it is uncommon in the faeces of the general population in developed countries [10,12,13].…”