Human and livestock migrations: a history of bot fly biodiversity in the Mediterranean region

Eimeria leuckarti in equid coprolites from the Sassanid Era (2nd-6th century CE) excavated in Chehrabad Salt Mine archaeological site, Iran

OBJECTIVE

This study reports coccidian oocysts in an equid coprolite dated to the Sassanid Empire (2nd-6th century CE) recovered in Chehrabad Salt Mine archaeological site, Iran.

METHODS

Between 2015 and 2017, an archaeoparasitological investigation led to the discovery of an equid coprolite in the Chehrabad Salt Mine archeological site, (Douzlakh), western Iran. Samples were rehydrated using trisodium phosphate solution and were examined by light microscopy.

RESULTS

Seven oocysts of Eimeria leuckarti (Flesch, 1883) were identified; they were in various stages of sporulation.

CONCLUSION

This is the first report of ancient coccidian oocysts from equids. The importance of this observation is discussed, and current knowledge of eimeriid oocysts at archaeological sites is reviewed.

SIGNIFICANCE

The observations of E. leuckarti increases current knowledge of parasite biodiversity in ancient Iran when it rested along the Silk Road, a network of trade routes connecting the East and West that was central to economic, cultural, political, and religious interactions between these regions, and to livestock movement that could contribute to the transmission of the parasites from/to other regions.

LIMITATIONS

The contextual information about animal species present in and around the Salt Mine during its working periods, including Achaemenid dynasty (6th to 4th century BCE) and Sassanid era (2nd to 6th century CE), is very limited and does not allow secure conclusions regarding the host origin of the coprolites.

SUGGESTIONS FOR FURTHER RESEARCH

Application of molecular biology tools to identify the correct host origin of the coprolites and to detect more parasite species is advocated.

Tracking the existence of Dioctophyma renale in Parthian Empire of Iran (247 BC-224 AD)

Paleoparasitological investigation in the archeological site of the Caspian Sea littoral revealed the presence of human Dioctophyma renale infection, a ubiquitous kidney-residing helminth of mammals, during the Parthian Empire of Iran (247 BC-224 AD). This study reports the oldest human infection with giant kidney worm in the Middle East, mainly in an area where the infection is reported nowadays. The paucity of records throughout the literature suggests that the same species of parasite occurred with low frequency in the past, as well. The cemetery in the archeological site of Kiasar represented a unique opportunity of studying human and animal parasites of the Parthian Empire in Iran.

Genomic palaeoparasitology traced the occurrence of Taenia asiatica in ancient Iran (Sassanid Empire, 2th cent. CE-6th cent. CE)

Palaeoparasitology investigates parasitological infections in animals and humans of past distance by examining biological remains. Palaeofaeces (or coprolites) are biological remains that provide valuable information on the disease, diet, and population movements in ancient times. Today, advances in detecting ancient DNA have cast light on dark corners that microscopy could never reach. The archaeological site of the Chehrabad salt mine of Achaemenid (550–330 BC) and Sassanid (third–seventh century AD) provides remains of various biotic and abiotic samples, including animal coprolites, for multidisciplinary studies. In the present work, we investigated coprolites for helminth eggs and larvae by microscopy and traced their biological agents’ DNA by Next Generation Sequencing. Our results revealed various helminths, including Taenia asiatica, the species introduced in the 1990s. Implementing advanced modern molecular techniques like NGS gives a paramount view of pathogenic agents in space and time.

Oestrid myiasis at a cross-road

The oestrids are a genuinely unique group of Diptera that represent many species whose larvae parasitize mammals, feeding on live tissues of a wide range of hosts, from mice to elephants, causing obligatory myiases. Those have had greatest impact on the activities of humans and their use of animals (e.g., as food, recreation, in the conduct of wars). To a large extent their impact has been controlled through the use of therapeutic application of synthetic chemical treatments. While in some limited cases eradication has been achieved, it is unlikely to become the norm as these parasites seem well adapted to survive at low population densities and small smoldering foci are likely to present a challenge in the future. Should organic production eschew the use of parasiticides, other than for rescue of seriously ill animals, the foci of infection by these parasites will remain. In this article, we explore current scientific information on this group of parasites that may have become an anachronism in modern livestock parasitology, identify gaps in our knowledge as well as the suggestions for the management of these parasites in the era of genomics and proteomics.

Parasitic diseases of equids in Iran (1931-2020): a literature review

Parasitic infections can cause many respiratory, digestive and other diseases and contribute to some performance conditions in equids. However, knowledge on the biodiversity of parasites of equids in Iran is still limited. The present review covers all the information about parasitic diseases of horses, donkeys, mules and wild asses in Iran published as articles in Iranian and international journals, dissertations and congress papers from 1931 to July 2020. Parasites so far described in Iranian equids include species of 9 genera of the Protozoa (Trypanosoma, Giardia, Eimeria, Klossiella, Cryptosporidium, Toxoplasma, Neospora, Theileria and Babesia), 50 helminth species from the digestive system (i.e., 2 trematodes, 3 cestodes and 37 nematodes) and from other organs (i.e., Schistosoma turkestanica, Echinococcus granulosus, Dictyocaulus arnfieldi, Parafilaria multipapillosa, Setaria equina and 3 Onchocerca spp.). Furthermore, 16 species of hard ticks, 3 mite species causing mange, 2 lice species, and larvae of 4 Gastrophilus species and Hippobosca equina have been reported from equids in Iran. Archeoparasitological findings in coprolites of equids include Fasciola hepatica, Oxyuris equi, Anoplocephala spp. and intestinal strongyles. Parasitic diseases are important issues in terms of animal welfare, economics and public health; however, parasites and parasitic diseases of equines have not received adequate attention compared with ruminants and camels in Iran. The present review highlights the knowledge gaps related to equines about the presence, species, genotypes and subtypes of Neospora hughesi, Sarcocystis spp., Trichinella spp., Cryptosporidium spp., Giardia duodenalis, Blastocystis and microsporidia. Identification of ticks vectoring pathogenic parasites, bacteria and viruses has received little attention, too. The efficacy of common horse wormers also needs to be evaluated systematically.

Monthly variations of Rhinoestrus spp. (Diptera: Oestridae) larvae infesting donkeys in Egypt: Morphological and molecular identification of third stage larvae

This study was carried out to investigate the prevalence and monthly intensity of Rhinoestrus (R) spp. among donkeys slaughtered at Giza Zoo abattoir, Egypt. A total of 144 donkeys were examined at postmortem through two visits per month from January 2010 to December 2010. All donkeys were infested with one or more larval stages during all months of the examination period (100%). The 1st and 2nd stage larvae (L1 and L2) were mostly observed in the turbinate bones and seldom in the nasal passages, whereas the 3rd stage larvae (L3) were observed mostly in ethmoid and lamina cribrosa and rarely in nasal passages and pharynx. The highest monthly intensity of infestation with the total number of larval stages was recorded in January and August, while the lowest occurred in September. L1 was observed during all months with two peaks in January and June. L2 occurred from February to April, July, and August. L3 was present from March to May, August, and September. The ranked size of infestation with the total number of the 3 larval stages of Rhinoestrus spp. showed that a total of 107 donkeys had 1-10 larvae; 34 had 11-30 larvae; and 3 harbored 31-50 larvae. The morphology and molecular characterization of the third stage larvae of Rhinoestrus spp. were investigated. Morphologically, two morphotypes (1 and 2) of Rhinoestrus spp. (R. usbekistanicus like and the other R. purpureus like) were reported. Whereas molecular sequencing of mitochondrial cytochrome-oxidase subunit I showed 99% homology with those of R. usbekistanicus. In conclusion, Rhinoestrus spp. present in Egypt is mainly R. usbekistanicus, which includes two morphotypes, R. usbekistanicus like and R. purpureus like.

The enigma of the dog mummy from ancient Egypt and the origin of 'Rhipicephalus sanguineus'

BACKGROUND

Ticks belonging to the Rhipicephalus sanguineus group are amongst the most important vectors of pathogenic microorganisms to dogs and humans. However, the taxonomy of this species group is still the subject of debate, especially because there is no type specimen or reliable morphological description for Rhipicephalus sanguineus sensu stricto. Recently, a comprehensive morphological and genetic study on representative tick specimens from Europe, Africa, Americas, and Oceania, revealed the existence of at least four morphologically and genetically distinct species under the name 'R. sanguineus' infesting dogs from different countries.

METHODS

Herein, we examined morphologically tick specimens retrieved on a dog mummy from Ancient Egypt (ca. 1st century - 4th century A.D.). The dog mummy and associated ticks were found during an archaeological expedition conducted in El Deir.

RESULTS

Scanning electron micrographs allowed us to assess their identity as belonging to the R. sanguineus group. In addition on the basis of the scutal punctation pattern, spiracular plates, width of dorsal tail of spiracular plates relative to the adjacent festoon, female genital aperture, male adanal plates and accessory shields, these ticks were tentatively identified as Rhipicephalus sp. II (=temperate species).

CONCLUSIONS

It can be concluded that R. sanguineus group ticks have infested dogs living in the Mediterranean region since ancient times. This finding represents the oldest record of ticks on any animal species and adds a new piece in the complex puzzle regarding tick parasitism on dogs and humans and their role as vectors of pathogens.

The phylogeographic history of the new world screwworm fly, inferred by approximate bayesian computation analysis

Insect pest phylogeography might be shaped both by biogeographic events and by human influence. Here, we conducted an approximate Bayesian computation (ABC) analysis to investigate the phylogeography of the New World screwworm fly, Cochliomyia hominivorax, with the aim of understanding its population history and its order and time of divergence. Our ABC analysis supports that populations spread from North to South in the Americas, in at least two different moments. The first split occurred between the North/Central American and South American populations in the end of the Last Glacial Maximum (15,300-19,000 YBP). The second split occurred between the North and South Amazonian populations in the transition between the Pleistocene and the Holocene eras (9,100-11,000 YBP). The species also experienced population expansion. Phylogenetic analysis likewise suggests this north to south colonization and Maxent models suggest an increase in the number of suitable areas in South America from the past to present. We found that the phylogeographic patterns observed in C. hominivorax cannot be explained only by climatic oscillations and can be connected to host population histories. Interestingly we found these patterns are very coincident with general patterns of ancient human movements in the Americas, suggesting that humans might have played a crucial role in shaping the distribution and population structure of this insect pest. This work presents the first hypothesis test regarding the processes that shaped the current phylogeographic structure of C. hominivorax and represents an alternate perspective on investigating the problem of insect pests.

Species diversity and abundance of ticks in three habitats in southern Italy

A 2-year study was conducted from March 2010 to March 2012 in a forested area in southern Italy to evaluate the species diversity and abundance of free-living ticks in 3 different habitats: (i) a meadow habitat within an enclosure inhabited by roe deer (Capreolus capreolus); (ii) a man-made trail located in a high-altitude, forested area; and (iii) a grassland near a house inhabited by 3 people. In total, 10,795 ticks were collected. Ixodes ricinus was the most abundant species (69.0%), followed by Haemaphysalis inermis (19.1%), Rhipicephalus turanicus (6.7%), Dermacentor marginatus (3.2%), and Hyalomma marginatum (1.0%). The least frequently collected species were Rhipicephalus bursa, Haemaphysalis parva, Haemaphysalis sulcata, and Haemaphysalis concinna, representing together less than 1% of the collections. Immature ticks predominated over adult ticks. In particular, immature stages of Ix. ricinus (i.e., 3246 larvae and 3554 nymphs) represented 63% of the total number of ticks collected. High levels of species diversity and abundance of ticks were recorded in all habitats and the daily number of ticks collected was negatively correlated with daily mean temperature, evapotranspiration, and saturation deficit. This study indicates that the southern Italian climate is suitable for different tick species, which may find a preferred 'climate niche' during a specific season, when a combination of factors (e.g., suitable meteorological and environmental conditions) associated with the presence of suitable hosts will facilitate their development and reproduction.

Nasal bots...a fascinating world!

Larvae causing obligatory myiasis are numerous and they may affect cutaneous and subcutaneous tissues, wounds, nasopharyngeal cavities (nasal bots), internal organs and the digestive tract (bots) of domestic and wild animals and humans as well. Nasal bots belong to the Family Oestridae, Subfamily Oestrinae, which includes several important genera: Oestrus, Kirkioestrus, and Gedoelstia infecting Artiodactyla (except Cervidae) in Africa and Eurasia, Cephenemyia and Pharyngomyia infecting Cervidae, Rhinoestrus infecting horses, Cephalopina infecting camels, Pharyngobolus infecting African elephants, and Tracheomyia infecting Australian kangaroos. Nasal bots are widespread in Mediterranean and tropical areas and in affected animals they induce sneezing and nasal discharge which may become caked with dust making breathing very difficult. The aforementioned species of larvae are host-specific but sometimes the may be deposited in human eyes inducing a painful opthalmomyiasis of short duration. The first fascinating trait of these parasites is the very efficient morphological and biological adaptations to parasitism they show either as larvae or as adults, in order to facilitate their survival and search for a suitable host. Nasal bots have reached different degrees of complexity in their life cycles. Indeed, while for some species (e.g., Oestrus ovis, Rhinoestrus usbekistanicus) larvae are injected by flies directly into nostrils and develop in the sinuses before being ejected for external pupation, some other species migrate from eyes to blood before returning to nasal cavities either through the ethmoid bone (Gedoelstia hässleri) or via lungs and bronchi (Gedoelstia cristata). Moreover, larvae are very well-adapted to their environment being able to undergo through hypobiosis either inside or outside the host, according to the climatic environmental conditions and seasonality. The second fascinating trait of nasal bots is related to host behavioural and immune responses against the infection. Host behaviour may in fact prevent larviposition and inflammatory/immune reactions limit larval development. The main pathophysiological mechanisms involve mast cells and eosinophils which destroy the larvae in sensitized animals. The intense eosinophilic reaction has side effects both locally (i.e. on the nasal mucosa) and also generally, with possible interactions with gastrointestinal strongyles (e.g., both worm burdens and fecundity decreased in lambs infected by O. ovis). Infected animals (e.g., sheep, goat, camel, and donkey) firstly suffer from fly strike, when adult flies inject first stage larvae on nostrils: sheep may try to avoid fly swarms but eventually Rangifer tarandus can only manage a terror-stricken look! Secondly, hosts will suffer from myiasis with typical nasal discharge and sneezing related to sinusitis. Clinical manifestations may vary: for example O. ovis induces severe clinical signs in sheep whilst produces few effects in goats! These parasites are diffused in many Mediterranean and tropical countries. Unfortunately, it is commonly believed that bacterial infections induced by nasal bots are of greater clinical importance: this view is not substantiated and the control of this condition depends on treatment with macrocyclic lactones, closantel and nitroxynil. Reinfections are common, and controlling nasal bots is not so simple.

Obesity in Mediterranean region (1997-2007): a systematic review

The objective of this review is to determine the distribution of obesity by geographical location, income, age and sex in the Mediterranean region during the last decade. A meta-analysis was conducted for 102 articles cited during the period (1997-2007) in Medline database (for 17 Mediterranean countries) searched during the summer of 2007 using the word 'obesity' and its related keywords. The study showed that adults were more obese than children in all Mediterranean continents and in different levels of income. The prevalence of obesity among European children was higher than among Asians. Also, European adults were more obese than European children. The total female adults were found to be more obese (median: 25.3%) than male adults (median: 20.0%). The regression model analysis indicated that male adults were more likely to be obese in the Euro-Med region. Taking different factors into consideration, it was noticed that Mediterranean adults, especially those in the European region, are at higher risk of obesity. Awareness programmes addressing the importance of adopting healthy dietary habits combined with physical activity should target the whole community in general and adults in particular. The findings could guide health planners for better management of obesity.

Molecular cross-sectional survey of gastric habronemosis in horses

Gastric habronemosis of horses caused by Habronema microstoma and Habronema muscae (Nematoda, Spirurida) is characterized by catarrhal gastritis, diarrhoea, progressive weight loss and ulcers. Despite its importance in the equine industry and in clinical practice, knowledge of the epidemiology of this infection is still incomplete as diagnosis in live animals is challenging. A two-step semi-nested PCR assay using ribosomal DNA (rDNA) markers has recently been used for the molecular diagnosis in vivo of gastric habronemosis based on the detection of H. microstoma and/or H. muscae DNA in equine faeces. To evaluate the field efficacy of this assay, a molecular epidemiological survey was carried out on equid gastric habronemosis in central Italy. One hundred and fifty-three individual faecal samples were collected from live native horses and subjected to both coprological examination and the two-step semi-nested PCR. When flotation procedures were performed no horse tested positive for Habronema spp. larvated eggs while 96 animals (61.2%) were positive for other endoparasites (i.e. strongyles, oxyurids, ascarids). Two-step semi-nested PCR detected 86 samples (53.6%) that were positive for H. microstoma and/or H. muscae DNA. H. microstoma prevalences showed statistically significant differences; the highest prevalence was observed in horses infected by other gastrointestinal parasites and concomitantly by H. muscae. No statistical differences were found between the prevalence of Habronema spp. infection and sex, age, breeding management, and antiparasitic treatments. This field survey provided further information on habronemosis and its epidemiology.