Echinococcus ortleppi and Echinococcus canadensis G6/7 affect domestic animals in western Zambia

Echinococcus species in wildlife

Transmission of Echinococcus spp. in life cycles that involve mainly wildlife is well recognized for those species with small mammals as intermediate hosts (e. g. E. multilocularis), as well as for E. felidis and the 'northern' genotypes of E. canadensis (G8 and G10). In contrast, the remaining taxa of E. granulosus sensu lato are best known for their domestic life cycles, and the numerous wild mammal species (mainly ungulates) that have been recorded with cystic echinococcosis in the past were mainly considered a result of spill-over from the dog-livestock transmission system. This view was challenged with the advent of molecular characterization, allowing discrimination of the metacestodes, although the contribution of wild mammals to various Echinococcus life cycles has remained uncertain for scarcity of wildlife studies. Numerous records of cysts in wild ungulates date back to the 20th century, but cannot with certainty be allocated to the Echinococcus species and genotypes that are recognized today. This means that our current knowledge is largely restricted to studies of the past two decades that kept adding gradually to our concepts of transmission in various geographic regions. In particular, new insights were gathered in the past years on E. granulosus s.l. in wildlife of sub-Saharan Africa, but also on transmission patterns of E. multilocularis in previously neglected regions, e. g. North America. Here, an update is provided on the current state of knowledge on wild mammals as hosts for all Echinococcus species, listing >150 species of wild hosts with references, as well as estimates on their epidemiological impact and our current gaps of knowledge.

Dogs' health and demographics in wildlife-populated and tsetse-infested villages of Mambwe district, eastern Zambia

Good dog-keeping practices and access to veterinary care are essential for the well-being of dogs. As the main causes of morbidity and mortality in the rural canine population in Zambia are poorly understood, we followed a cohort of 162 indigenous dogs for six months in wildlife-populated and tsetse-infested villages of Mambwe district, eastern Zambia to gain deeper insights. Dogs lacked basic home and veterinary care, they were often starved and burdened with ticks, and some passed live adult worms in their stool. The frequent exposure of dogs to tsetse bites and consumption of fresh raw game meat and bones puts them at greater risk of acquiring African trypanosomiasis. Nearly 20 % of dogs were lost to follow-up, with the main causes being poor health (58.1 %), predation by wild carnivores (29 %), and owner culling or euthanasia (12.9 %). We observed that indigenous dogs' general well-being and survival were largely influenced by their environment, infectious diseases, injuries sustained during interaction with conspecifics and wildlife, and community attitudes and practices associated with dog ownership.

First report of Echinococcus ortleppi and E. canadensis (genotype G6) from southern Punjab, Pakistan and a global overview on genetic structure and host adaptation of E. ortleppi

Cystic echinococcosis (CE), caused by Echinococcus granulosus sensu lato, is a neglected tropical disease known mainly for its zoonotic nature. CE is endemic to Pakistan, however, the disease is not given due consideration and millions of people remain at health risk. This study was undertaken to assess the species and genotypes of E. granulosus sensu lato in sheep, buffaloes and cattle, brought to slaughterhouses of two major cities (Multan and Bahawalpur) of south Punjab, Pakistan. A total of 26 hydatid cyst specimens were characterized through complete cox1 mitochondrial gene (1609 bp) sequencing. Species and genotypes of E. granulosus sensu lato discovered in the southern Punjab consisted of E. granulosus sensu stricto (n =21), E. ortleppi (n=4) and E. canadensis G6 genotype (n=1). Of E. granulosus s.s. isolates, the genotype G3 was predominantly involved in causing infections to the livestock of this region. Since all of these species are zoonotic, wide and effective surveillance studies are required to ascertain the risks to human population in Pakistan. Additionally, a global overview on cox1 phylogenetic structure of E. ortleppi was carried out. Despite the widespread occurrence, the species is mostly limited to the southern hemisphere. The highest burden has been reported in the South America (62.15%) and Africa (28.44%) and by far the most common host is cattle, accounting for >90% of cases.

Cystic echinococcosis of ruminant livestock in Namibia

Cystic echinococcosis (CE) is widespread and locally frequent in southern Africa where it affects humans, livestock, and wild mammals. However, most data from the region are old and do not provide information on the causative Echinococcus species. For Namibian livestock only anecdotal records were available prior to this preliminary survey. Our retrospective analysis of slaughterhouse records of CE in cattle from the commercial farming area in central and southern Namibia resulted in 1.65% CE prevalence among 35,143 slaughtered cattle in the period 2015-2016. For comparison, carcasses of ruminant livestock were prospectively examined in the communal farming areas of northern Namibia, resulting in three CE cases among only 12 cattle, and no cases among nine goats. To determine the Echinococcus species affecting Namibian livestock, a total of 53 cysts were collected from all parts of the country and analysed for species and genotype by amplification and sequencing of the nad1 gene. All 50 cattle cysts (isolated from 40 cattle), both from the commercial and communal farming areas, were Echinococcus ortleppi (all fertile, and 42/50 from the lungs), while three opportunistically collected cysts from three sheep in southern Namibia were E. canadensis G7. Our data suggest that E. ortleppi is the only CE agent that is relevant for cattle infection in Namibia, and that low prevalence in the commercial farming areas contrasts with high CE burden in the northern traditional husbandry systems. The present data provide baseline information to stimulate epidemiological studies on the transmission pathways of various CE agents in livestock, wildlife, and humans in Namibia and neighbouring countries.

Prevalence and molecular characterization of cystic hydatidosis in livestock slaughtered in southern Mozambique

Hydatid disease is a parasitic zoonosis caused by genotypes of the genus Echinococcus. This disease inflicts economic loses in livestock and cause public health burden in resource poor mostly in developing countries. The aim of this study was to determine the prevalence and identity of the genotypes responsible for hydatid cysts in cattle, goats and pigs slaughtered at selected abattoirs of southern provinces of Mozambique. Cysts were collected from liver and lungs and hydatid confirmation was made by cystic membrane observation and visualization of protoscoleces by light microscope. Thirty-two hydatid cysts from 817 cattle and two from 68 pigs were collected from local slaughterhouses and slabs. DNA was extracted from protoscoleces of each cyst together with the cystic membrane and amplified based on the mitochondrial subunit 1 of the cox1 and nad1 gene. The overall prevalence of hydatid cysts was 3.9% in cattle, 2.9% in pigs and none of the goats were found with cysts. All cysts collected from cattle and pigs were identified as Echinococcus ortleppi (G5) with a minimum homology of 99% on BLAST analysis. Our results confirm the presence of E. ortleppi in cattle and pigs in southern Mozambique at a low prevalence and further studies are recommended to determine the risk factors favoring the transmission of this zoonotic parasite in the resource-poor livestock farming communities of this region.

Ocurrence of enteroparasites with zoonotic potential in animals of the rural area of San Andres, Chimborazo, Ecuador

OBJECTIVE

The aim of this research was the identification of the enteroparasites harbored by the animals of the San Andrés community, to evaluate their role as susceptible hosts and sources of infection for other animals, humans (zoonoses), as well as parasite forms spreaders to the environment in this rural area, located in the province of Chimborazo, Ecuadorian Andean region.

MATERIAL AND METHODS

The study was carried out combining 3 coproparasitological techniques: direct examination, Ritchie and Ziehl-Neelsen in 300 animal stool samples RESULTS: Blastocystis sp., Entamoeba spp., Giardia spp., Balantidium spp., Cryptosporidium spp., Ascaris spp., Toxocara spp., Ancylostoma spp., Strongylida, Hymenolepis nana and Echinococcus spp., were detected. Infection by protozoa (87.3%) was higher than helminths (31.0%). All cattle, sheep and guinea pigs were found parasitized, and the presence of Blastocystis sp., Entamoeba spp. and Cryptosporidium spp. by all groups of animals stands out. It is also remarkable the presence of Giardia spp. in swine (19.2%), big herbivores-livestock (11.5%), leporids (8.3%) and carnivores (5.9%); Balantidium spp. in swine (19.2%), big herbivores-livestock (5.8%) and carnivores (1.2%); Hymenolepis nana in guinea pigs (2.1%); and Toxocara spp. (15.7%), Echinococcus spp. (9.6%) and Ancylostoma spp. (6.0%) in dogs.

CONCLUSION

Animals from San Andrés have a wide spectrum of intestinal parasitic forms in their feces, being a source of infection to other animals and humans, and a source of contamination of the environment, posing a risk factor and reinforcing the idea of the need for more effective treatments and hygienic measures to improve livestock production and cutting its transmission.

Advances in the treatment, diagnosis, control and scientific understanding of taeniid cestode parasite infections over the past 50 years

In the past 50 years, enormous progress has been made in the diagnosis, treatment and control of taeniid cestode infections/diseases and in the scientific understanding thereof. Most interest in this group of parasites stems from the serious diseases that they cause in humans. It is through this lens that we summarize here the most important breakthroughs that have made a difference to the treatment of human diseases caused by these parasites, reduction in transmission of the taeniid species associated with human disease, or understanding of the parasites' biology likely to impact diagnosis or treatment in the foreseeable future. Key topics discussed are the introduction of anti-cestode drugs, including benzimidazoles and praziquantel, and the development of new imaging modalities that have transformed the diagnosis and post-treatment monitoring of human echinococcoses and neurocysticercosis. The availability of new anti-cestode drugs for use in dogs and a detailed understanding of the transmission dynamics of Echinococcus granulosus sensu lato have underpinned successful programs that have eliminated cystic echinococcosis in some areas of the world and greatly reduced the incidence of infection in others. Despite these successes, cystic and alveolar echinococcosis and neurocysticercosis continue to be prevalent in many parts of the world, requiring new or renewed efforts to prevent the associated taeniid infections. Major advances made in the development of practical vaccines against E. granulosus and Taenia solium will hopefully assist in this endeavour, as might the understanding of the parasites' biology that have come from an elucidation of the nuclear genomes of each of the most important taeniid species causing human diseases.

Three species of Echinococcus granulosus sensu lato infect camels on the Arabian Peninsula

We report on the genetic identity of 36 Echinococcus cysts that were collected during a recent slaughterhouse survey of 810 locally bred camels (dromedaries) in the Eastern Province of the Kingdom of Saudi Arabia. Analysis of a partial nad1 gene sequence showed that the majority (n = 29) belonged to E. granulosus sensu stricto, four to E. canadensis G6/7, and three to E. ortleppi. Eight of the 29 E. granulosus s.s. cysts contained protoscoleces; all other cysts were calcified and non-viable. This is the first report of the presence E. ortleppi from the Arabian Peninsula, a parasite that is typically transmitted via cattle. The results indicate widespread infection of camels with CE in eastern Saudi Arabia and an active role of camels in the lifecycles of at least E. granulosus s.s.. Complete cox1 haplotype analysis of 21 E. granulosus s.s. isolates shows that the majority of variants circulating in eastern Saudi Arabia is distinct from but closely related to haplotypes from neighboring countries in the Middle East, which indicates the presence of this parasite in KSA for a longer period of time. All isolates of E. granulosus s.s. in this study belonged to the G1 cluster, although the G3 genotype has previously also been reported from the Middle East.