Populations of blue-footed boobies in the Galápagos Islands have declined by at least 50% compared with numbers recorded during the 1960s. Recently, concern has been expressed about potential adverse effects of introduced blood parasites; in particular, malarial parasites (i.e. Plasmodium sp.), which are frequently pathogenic and can cause mortality and morbidity in birds, and blood parasites of the genus Haemoproteus, which can reduce fitness. We screened blue-footed boobies at six breeding colonies within Galápagos for both genera of parasite. At two sites, we also investigated whether there was any relationship between infection status and physiological condition or breeding success. We found a high prevalence of Haemoproteus spp. in adults and chicks using PCR, although none was found on blood smears. We found no evidence of Plasmodium. Effects of parasitism on the condition of birds were limited. Also, there was no evidence that infection with Haemoproteus adversely affected breeding success or chick growth. Our results suggest that poor success of breeding birds was not strongly associated with Haemoproteus infection. However, regular colony monitoring and examination of dead birds are necessary to assess whether acute Haemoproteus infection might be responsible for some mortality, particularly of chicks.

Partial mitochondrial cytochrome c oxidase subunit I (mt COI) sequences were generated from: Toxoplasma gondii (strains CTG, GTI, MAS, ME49, PTG, TgCatBr5, TgCat, Br64, TgCgCal, TgToucan); Neospora caninum (Strain NC1); Hammondia hammondi (Strain H.H–20); H. heydorni; H. cf. triffittae; Cystoisospora felis; C. suis; C. canis; C. rivolta; C. cf. ohioensis; Caryospora bigenetica; Sarcocystis rileyi; and S. neurona. Nuclear 18S rDNA sequences were generated for H. heydorni, H. hammondi, C. suis, C. canis, C. felis, C. rivolta, C. cf. ohioensis, S. neurona, and S. rileyi. Aligned, concatenated 18S rDNA and COI sequences were Bayesian analysed using partitioned nucleotide substitution models [HKY + I + G for 18S; GTR + I + G codon (code = metmt) for COI]. Phylogenetic hypotheses supported a monophyletic Sarcocystidae and its subfamilie with two major clades within the Toxoplasmatinae: (1) a monophyletic clade of Cystoisospora spp. with Nephroisospora eptesici; and (2) a clade of Toxoplasma, Neospora and Hammondia. Within the latter, Hammondia was shown to be paraphyletic; H. heydorni and H. triffittae were monophyletic with N. caninum [canine definitive hosts (DHs)], whereas H. hammondi was monophyletic with T. gondii (feline DHs). A new genus is erected to resolve the paraphyly of the genus Hammondia confirmed using mt COI and combined 18S/COI sequence datasets.

Head lice (Pediculus humanus capitis) infestations are a public health concern. The insecticidal properties of the Australian native plant Kunzea ambigua (commonly known as tick bush) have been documented. In this study, we tested activity of kunzea oil (KO) against head lice through in vitro bioassays. Head lice were exposed to filter paper treated with either KO, as either a 5 or 100% oil, or commercial formulations containing either permethrin or tea tree oil (TTO) for 120 min. Head lice exposure to KO, both as a 5 and 100% solution oil, resulted in 100% mortality within 120 min with a mean survival times of 17·1 and 34·8 min, respectively. There was no significant difference between the mean mortality of head lice exposed to 5% KO (17·1 ± 1·0; 95% CI: 115·2–19·0) and 5% TTO (21·2 ± 1·9; 95% CI: 17·4–25·1). This study revealed, for the first time, that KO holds great potential as an effective alternative to current active ingredients contained within commercial pediculicide formulations.

Trypanosomes and Leishmania are vector-borne parasites associated with high morbidity and mortality. Trypanosoma lewisi, putatively introduced with black rats and fleas, has been implicated in the extinction of two native rodents on Christmas Island (CI) and native trypanosomes are hypothesized to have caused decline in Australian marsupial populations on the mainland. This study investigated the distribution and prevalence of Trypanosoma spp. and Leishmania spp. in two introduced pests (cats and black rats) for three Australian locations. Molecular screening (PCR) on spleen tissue was performed on cats from CI (n = 35), Dirk Hartog Island (DHI; n = 23) and southwest Western Australia (swWA) (n = 58), and black rats from CI only (n = 46). Despite the continued presence of the intermediate and mechanical hosts of T. lewisi, there was no evidence of trypanosome or Leishmania infection in cats or rats from CI. Trypanosomes were not identified in cats from DHI or swWA. These findings suggest T. lewisi is no longer present on CI and endemic Trypanosoma spp. do not infect cats or rats in these locations.

Cryptosporidium is a well-known cause of neonatal enteritis in cattle worldwide. Cattle are commonly infected with four different species of Cryptosporidium but only one of these, Cryptosporidium parvum, is associated with clinical disease. Identification of species in cases of calf scour can give an indication if Cryptosporidium is the causative agent or not. In addition, C. parvum is a zoonotic species and so has implications for human health, for this reason it is important to identify the species of Cryptosporidium infecting cattle particularly where a farm is implicated in an outbreak of cryptosporidiosis in humans. Here a multiplex PCR test, which can identify the four common cattle-adapted Cryptosporidium species, including C. parvum, has been developed. This test allows quick and accurate detection of Cryptosporidium species in cattle fecal samples including mixed infections, which could be missed by the more common method of sequencing the same gene.

Tick-borne apicomplexan haemoparasites infect wild and domestic animals, but studies on their distribution among free-living animals are comparatively fewer. Tissues from 241 wild carnivores of eight Mustelidae, two Canidae, one Viverridae and one Felidae species were collected in Northern Spain, and analysed by real-time PCR targeting the 18S rRNA gene and sequencing. Babesia vulpes (formerly known as Theileria annae) was the only piroplasm detected in red foxes (Vulpes vulpes). Badgers (Meles meles) were shown to harbour two novel Babesia sp. sequence types (A and B) that only shared 96.7% homology between them and were closely related (ca. 97–98%) to, but distinct from B. vulpes and other babesia from carnivores. Analysis of PCR-derived sequences also revealed the presence of Cystoisospora sp. and Hepatozoon sp. in badgers and showed that wild cats (Felis silvestris catus) were infected with Cytauxzoon sp. Forty-two per cent of the animals subjected to a detailed external examination were parasitized by ixodid ticks, being Ixodes hexagonus and Ixodes ricinus the most abundant species. This study provided novel data on the different haemoparasites that can infect European wild carnivores and showed that they can be hosts for a range of haemoparasites and pose a potential risk for transmission to domestic animals.

Oxyspirura petrowi is a heteroxenous parasitic nematode that has been reported in high prevalences from birds in the Order Galliformes experiencing population declines in the USA. There is a paucity of information regarding the natural history O. petrowi, including the life cycle and effects of infection on wild bird populations. In order to study the life cycle of this parasite, we collected plains lubber grasshoppers (Brachystola magna) from a field location in Mitchell County, Texas. We found third-stage larvae (L3) in 37.9% (66/174) B. magna. We determined that they were O. petrowi through morphological comparison of L3 from experimentally infected Acheta domesticus and by sequence analysis. Then, we showed that B. magna are a potential intermediate hosts for O. petrowi infections in northern bobwhites (Colinus virginianus) in a laboratory setting by experimental infection. We first detected shedding of eggs in feces using a fecal float technique 52 days post infection. In addition, we recovered 87 O. petrowi from experimentally infected northern bobwhites. Although we detected shedding in feces, recovery of eggs was low (>5 eggs/g). Future work is needed to understand shedding routes and shedding patterns of northern bobwhites infected with O. petrowi.

Aelurostrongylus abstrusus is a worldwide occurring lungworm affecting felids. This metastrongyloid nematode has an indirect lifecycle relying on slugs and snails as intermediate hosts. In the present study the development of first-stage (L1) to third-stage larvae (L3) in the tropical freshwater pulmonate snail Biomphalaria glabrata was assessed. A total of 306 snails were individually exposed to 300 A. abstrusus L1, which were obtained from a naturally infected stray cat. The species was confirmed by biomolecular analysis. Second stage larvae (L2) and L3 were first isolated by artificial digestion of snails in the second and fourth week post exposure (wpe), respectively. From 8 wpe onwards, all larvae had developed into L3. Snails remained infected for up to 26 wpe. Only 0.4% of the L1 had pursued their development into L3, indicating low suitability of this artificial intermediate host for production of infective A. abstrusus L3.

Toxoplasmosis affects a third of the global population and is of particular concern for immunologically compromised individuals. Toxoplasmosis induces host physiological events ranging from immunological to metabolic responses across multiple biological compartments. To understand the sequence of host responses during acute and chronic Toxoplasma gondii infection, eight male BALB/c mice were infected with 2000 T. gondii ME49 tachyzoites with a further eight uninfected mice used as controls. Plasma cytokines status, urinary metabolic profiling and fecal microbial profiles were characterized to monitor temporal variation related to T. gondii infection. The results showed elevated serum interferon-γ (IFN-γ), interleukin-12p40 and  necrosis factor-α during acute phase of infection with concomitant perturbation in host energy metabolism and host-gut microbiome co-metabolism of phenolics and a shift in microbial composition. However, the differences were less pronounced during the putative chronic phase of infection with elevated IFN-γ, differences in urinary N-acetyls and O-acetyls of glycoproteins with no shift in gut microbial composition. Structural equation modelling on the current data showed host immune responses as the main driver for changes observed in urinary metabolites and gut microbial composition. Such an approach can be applied to other models of infectious diseases to aid understanding of host–pathogen interactions and potential biomarker discovery.

The transmission of parasites can be influenced by their co-occurrence with other parasites, in some cases increasing or reducing transmission. Trypanosoma cruzi, aetiologic agent of Chagas disease, often co-occurs with Trypanosoma rangeli, a parasite not pathogenic for mammal hosts. Both parasites can reduce the fitness of their insect vectors (the triatomine bugs; Hemiptera: Reduviidae), with T. rangeli being more pathogenic for some species. Here, we study the prevalence of T. cruzi and T. rangeli in the triatomine Rhodnius pallescens across a heterogeneously transformed landscape in Panamá. We found that single T. rangeli infections were more common in contiguously forested habitats, while single T. cruzi infections predominated in anthropogenically disturbed habitats. Trypanosoma cruzi–T. rangeli co-infections were more common in contiguous forests and in peridomiciliary areas. Furthermore, adult insects were more likely to be co-infected than nymphs. Our results suggest that human-mediated landscape transformation might have increased the predominance of single infections with T. cruzi within vectors. An important mechanism driving changes in trypanosome infection patterns in triatomines at a landscape scale includes alterations in host species composition that may vary with different degrees of deforestation. Trypanosome co-infection may also confer a survival advantage for R. pallescens to and/or throughout adulthood.

This study provides the first comprehensive information on the parasite fauna of the white-streaked grouper Epinephelus ongus. A total of 35 specimens from the archipelago Karimunjawa, Java Sea, Indonesia were studied for metazoan parasites. For comparison, the documented parasite community of 521 E. areolatus, E. coioides and E. fuscoguttatus from previous studies were analysed. A total of 17 different parasite taxa were recognized for E. ongus, including 14 new host and four new locality records. This increases the known parasite taxa of E. ongus by more than 80%. The ectoparasite fauna was predominated by the monogenean Pseudorhabdosynochus quadratus resulting in a low Shannon index of species diversity of the entire parasite community (0.17). By contrast, the species diversity excluding the ectoparasites reached the highest value recorded for Indonesian epinephelids (1.93). The endoparasite fauna was predominated by generalists, which are already known from Indonesia. This demonstrates the potential risk of parasite transmission through E. ongus into mariculture and vice versa. One-way analyses of similarity revealed a significantly different parasite community pattern of E. ongus compared with E. areolatus and E. fuscoguttatus as well as minor differences with E. coioides. This finding refers to different habitat preferences of these epinephelids within the analysed size range.

There is limited evidence of the prevalence of enteric protozoon infections in developed settings. We estimated the prevalence of enteric protozoa and evaluated the outcome of testing algorithms used in hospital settings in Sydney, Australia. This retrospective study assessed microbiological data from four public clinical laboratories. Pooled data from the four hospitals revealed the most common enteric protozoon detected was Blastocystis spp. in an average of 5·4% of cases, followed by Giardia intestinalis (1·1%) and Dientamoeba fragilis (0·8%). Protozoon detection rates between hospitals were significantly different and could be based on multiple factors. The modified iron haematoxylin staining method, consistently detected higher rates of Blastocystis spp., and G. intestinalis in comparison with microscopy of wet preparations, as well as higher rates of G. intestinalis and Cryptosporidium when compared with enzyme immunoassay. The study concludes that there are multiple factors that contribute to the variability in protozoa detection rates in metropolitan hospitals, including widespread variability in the testing protocols for enteric protozoa, individual and population characteristics. A gold standard approach for diagnosis of enteric protozoa is recommended. Molecular diagnostic methods such as polymerase chain reaction would provide consistency across laboratories and yield more reliable estimates of the actual prevalence of enteric protozoa.

Nematodes in the order Rhabditida, including species of Strongyloides and Pelodera, may be parasites of domestic animals. In this paper, we describe two apparent cases of rhabditid infections, one in a dog and one in a litter of piglets. The dog infection was originally considered likely to be an infection with Strongyloides, based on superficial morphological examination and PCR results without sequencing. However, more careful morphological analysis and inclusion of several molecular analyses, including sequencing, revealed that an infection with Pelodera sp. was more likely, probably Pelodera pseudoteres. Treatment with fenbendazole and selamectin was apparently successful. Similarly, based on both morphological and molecular analyses the apparent piglet infections were considered most likely to be with Rhabditis spp., possibly Rhabditis axei. The detection of larvae of nematodes in the order Rhabditida in fecal samples, particularly from dogs, may easily be considered as being indicative of Strongyloides infection. Given the zoonotic potential of canine Strongyloides, correct diagnosis is important. However, as illustrated by these two cases, careful morphological examination and measurement, supported by full molecular investigations, including sequencing, are essential in order to avoid this misdiagnosis.

The prevalence of placental malaria and its impact on maternal and newborn outcomes have been poorly documented in periurban settings of Burkina Faso. Peripheral and placental blood from 320 mothers, and cord blood from their newborns were collected through a cross-sectional study and used to prepare thick and thin blood films. Maternal haemoglobin concentration and birthweight were also measured. The overall malaria parasitaemia prevalence in peripheral, placental and cord blood was of 17·2, 9·1 and 0·9%, respectively. Plasmodium falciparum was the sole species found in all cases and the mean parasite density in placental blood was 4·5 ± 0·8 parasites µL−1. Primigravida (aOR: 3·5; 95% CI (1·1–11·2)) and women who did not use a bed net (aOR: 2·6; 95% CI (1·1–6·3)), were at higher odds of placental malaria infection. Women with placental parasitaemia were at increased odds of maternal anaemia (aOR: 3·1; 95% CI (1·3–7·4)). There was no odds difference for LBW between mothers with placental parasitaemia and those without. Placental malaria parasitaemia resulted in a significant mean birthweight reduction of 200 g. Placental malaria infection is higher in primigravida. Use of insecticide-treated bed nets should be therefore emphasized for primigravida during the first antenatal care visit.

The current mainstay for control of the four major helminth diseases in humans (lymphatic filariasis, onchocerciasis, soil-transmitted helminthiases and schistosomiasis) is with preventive chemotherapy by mass administration of key anthelminthics. Following the London Declaration on Neglected Tropical Diseases in 2012, a roadmap for the elimination and control of these helminthiases by 2020 has been devised. With expected declines in prevalence and intensity of these infections, there is urgent need for implementing more sensitive, high-throughput and cost-effective diagnostic tools. Currently available diagnostic approaches for surveying, monitoring and evaluating helminth control programmes are based on microscopical observation of eggs/larvae, and/or detection of antibodies or parasite antigens in stool, urine or blood; all relatively low-throughput and of limited sensitivity and specificity. Newly proposed approaches for helminthiases diagnosis include the nucleic acid-based methods of (multiplex) real-time polymerase chain reaction assays, loop-mediated isothermal amplification and recombinase polymerase amplification. However, as well as sensitivity/specificity evaluation, their comparison to current ‘gold standard’ diagnostics and future application in individual-/community-based diagnosis, or in xenomonitoring requires consideration of relative costs, agreement of standard methods and strategic interpretation of resulting data before control/elimination programmes might best utilize molecular diagnostics to inform decision making. We review current nucleic-acid-based molecular diagnostic methods and highlight the needs and future research required to refine these tools for monitoring and evaluation of control and elimination programmes for four major human helminthiases.

Leishmaniasis and dirofilariasis are parasitic diseases of humans and dogs, worldwide, and they are often found as coinfections in endemic areas. Cases of human and canine dirofilariasis have being reported in Greece and leishmaniasis is endemic in most prefectures in humans and dogs. In most cases, dirofilariasis is established by parasitological (the modified Knott's test) and/or immunological methods, whilst for leishmaniasis molecular techniques and culture are also used. During an epidemiological study in Greece, 22·1% of the 5772 dogs studied were found positive by serology for Leishmania. Blood cultures of 165 (12·94%) of these animals produced Leishmania promastigotes and 26 (2·03%) Dirofilaria microfilariae (L1), whilst only in two (0·16%) both Leishmania and Dirofilaria L1 appeared. The aim was to assess coinfections by the two parasites in dogs in Greece, the isolation and survival of Dirofilaria microfilariae and Leishmania promastigotes using clotted blood (a fast, simple and low-cost method) and the survival potential of the two parasites in coexistence, in vitro.

The infectivity and virulence of pathogenic trypanosomatids are directly associated with the efficacy of their antioxidant system. Among the molecules involved in the trypanosomatid response to reactive oxygen or nitrogen species, trypanothione reductase (TRed) is a key enzyme. In this study, we performed a molecular and functional characterization of the TRed enzyme from Trypanosoma rangeli (TrTRed), an avirulent trypanosome of mammals. The TrTRed gene has an open reading frame (ORF) of 1473 bp (~490 aa, 53 kDa) and occurs as a single-copy gene in the haploid genome. The predicted protein contains two oxidoreductase domains, which are equally expressed in the cytosol of epimastigotes and trypomastigotes. Nicotinamide adenine dinucleotide phosphate (NADPH) generation is reduced and endogenous H2O2 production is elevated in T. rangeli Choachí strain compared with T. cruzi Y strain epimastigotes. Oxidative stress induced by H2O2 does not induce significant alterations in TrTRed expression. Overexpression of TrTRed did not influence in vitro growth or differentiation into trypomastigotes, but mutant parasites showed increased resistance to H2O2-induced stress. Our results indicate that T. rangeli constitutively expresses TRed during the entire life cycle, with reduced levels during infective and non-replicative trypomastigote stages.