Occurrence of Ten Protozoan Enteric Pathogens in Three Non-Human Primate Populations

Abstract

Non-human primate populations act as potential reservoirs for human pathogens, including viruses, bacteria and parasites, which can lead to zoonotic infections. Furthermore, intestinal microorganisms may be pathogenic organisms to both non-human primates and humans. It is, therefore, essential to study the prevalence of these infectious agents in captive and wild non-human primates. This study aimed at showing the prevalence of the most frequently encountered human enteric protozoa in non-human primate populations based on qPCR detection. The three populations studied were common chimpanzees (Pan troglodytes) in Senegal and gorillas (Gorilla gorilla) in the Republic of the Congo and in the Beauval Zoo (France). Blastocystis spp. were mainly found, with an occurrence close to 100%, followed by Balantidiumcoli (23.7%), Giardiaintestinalis (7.9%), Encephalitozoonintestinalis (1.3%) and Dientamoebafragilis (0.2%). None of the following protozoa were detected: Entamoebahistolytica, Enterocytozoonbieneusi, Cryptosporidiumparvum, C. hominis, Cyclosporacayetanensis or Cystoisosporabelli. As chimpanzees and gorillas are genetically close to humans, it is important to monitor them frequently against different pathogens to protect these endangered species and to assess potential zoonotic transmissions to humans.

Intestinal Protists in Captive Non-human Primates and Their Handlers in Six European Zoological Gardens. Molecular Evidence of Zoonotic Transmission

“…This protist has been implicated in the aetiology of a range of different intestinal (i.e., irritable bowel syndrome, diarrhoea) and extra-intestinal (i.e., urticarial) diseases ( 79), but its true clinical significance remains unclear and controversial because asymptomatic carriage is the norm rather than the exception. This very same statement is also valid for captive NHP, where infection/carriage rates over 20% and up to 100% have been consistently found in studies conducted in Bangladesh (80), Brazil (81,82), China (83), France (53), Italy (50), Peru (84), Republic of the Congo and Senegal (53), and Spain (13,43). The occurrence rates identified in the present study (2-41%) are well in the range of those reported above, corroborating Blastocystis sp.…”

“…Interestingly, ST1-ST3 distribution was independent of NHP group or geographical association, ST5 was seen only in apes and old world monkeys, and ST8 primarily in species native to Asia or South America (85). Subsequent surveys have confirmed (13,53,82,84) or extended these preliminary molecular data. For instance, ST7 has been described in cynomolgus monkeys in Italy (50), ST13 in langurs and golden snub-nosed monkeys in Bangladesh (80) and China (83), ST17 in squirrel monkeys in China (86), and ST19 in a rhesus macaque in the latter country (83).…”

“…Cryptosporidium infection rates have been typically reported in the range of 3–6% in NHP species including baboons, gibbons, macaques, and orangutans ( 41 , 43 – 48 ). Other surveys failed to detect the parasite in their captive NHP collections ( 13 , 29 , 49 – 53 ). This variability is clearly reflected in the present study, where an overall Cryptosporidium infection rate of 1.0% was found, but the parasite was only detected in two of the six participating zoological institutions.…”

Presence and genetic diversity of enteric protists in captive and semi-captive non-human primates in côte d’Ivoire, Sierra Leone, and Peru

“…Blastocystis sp. has been documented at a prevalence of 22% by conventional microscopy in Cameroon ( Drakulovski et al, 2014 ), and of 6–100% by PCR in Senegal, the Republic of Congo, and Tanzania ( Petrášová et al, 2011 ; Renelies-Hamilton et al, 2019 ; Köster et al, 2021b ; Menu et al, 2021 ). Regarding genetic diversity, ST1 has been demonstrated as the most prevalent Blastocystis subtype circulating in free-living NHP in Africa, accounting for 80–100% of the isolates characterised in wild chimpanzees in Senegal ( Renelies-Hamilton et al, 2019 ; Köster et al, 2021b ) and Tanzania ( Petrášová et al, 2011 ), although in the former country few animals carried also ST2 and ST3.…”

Blastocystis is widely distributed in mammals and aves

“…infection. However, the infection rates vary from 0% to 100% in different localities, such as most nonhuman primates in the three zoos in Hangzhou, Dalian and Suzhou (0%) [12], black-capped capuchin (0%) and rhesus macaque (96.6%) in Qingling Mountains [20], wild chimpanzees in southeast Cameroon (21.9%) [21], gorillas in the Beauval zoo in France (88.9%), common chimpanzees in Senegal (97.9%), gorillas in the Republic of the Congo (100%) [22], rhesus monkeys in Nepal (100%) [23], javan lutung and guereza in Poland (100%) [24]. Something similar was going on in the following four groups.…”