We performed a long-term natural experiment investigating the impact of the diphyllobotriidean cestode Schistocephalus solidus on the body condition and clutch size (CS) of threespine stickleback Gasterosteus aculeatus, its second intermediate host, and the growth of larval parasites in host fish. We tested the hypothesis that single S. solidus infections were more virulent than multiple infections. We also asked whether the metrics of mean and total parasite mass (proxies for individual and total volume, respectively) were consistent with predictions of the resource constraints or the life history strategy (LHS) hypothesis for the growth of, hence exploitation by, larval helminths in intermediate hosts. The samples were drawn from Walby Lake, Alaska in eight of 11 years. Host body condition and CS (egg number per spawning bout) decreased significantly with intensity after adjustments for host size and parasite index. Thus, infections have an increasingly negative impact on measures of host fitness with greater intensity, in contrast to the hypothesis that single infections are more harmful than multiple infections. We also found that mean parasite mass decreased with intensity while total parasite mass increased with intensity as predicted by the LHS hypothesis.

Light and electron microscopy were used to study the ultrastructure of the cement apparatus, namely cement glands and cement ducts of mature specimens of the acanthocephalan parasite Pomphorhynchus laevis Müller, 1776, recovered from the digestive tracts of fish Leuciscus cephalus Risso, 1826. In addition, the cement glands of immature P. laevis found within the body cavity of the fish Alburnus alburnus alborella De Filippi, 1844 were examined. In a mature male of P. laevis the 6 cement glands are rounded to oval in shape and each of them has an outer cytoplasmic layer containing nuclei and surrounding a space for storage of the cement material within the gland. The nuclei have an irregular outline and the cytoplasm of the cells contains round, membrane-bound secretory granules approximately 1 μm in diameter. Nuclei surrounded by secretory granules were present inside the gland lumen. Within the gland ducts of mature males, granules were present within the wall thickness and, inside the luminal area, mitochondria were encountered. In contrast, within the cement glands of immature P. laevis there were no secretory granules and the chromatin of the nuclei appeared condensed. The nature of the secretory product of the cement glands was investigated with histological and electrophoretic methods. A protein with molecular weight of 23 kDa was recorded as a major component of cement.

This highly topical book offers information on two groups of communicable diseases: the first being zoonoses, with animals playing an essential role in maintaining the infection in nature and man is only an accidental host. The second group comprises the diseases common to man and animals, where they generally contract the infection from the same source, and the animals may contribute in particular to the distribution and actual transmission of infections.

Ecological and social changes, along with the migration of large numbers of people between continents, have caused the spread of once endemic diseases, which can now pose a threat in distant communities. The risk of bio-terrorism has highlighted the need for detailed knowledge of those diseases in terms of their epidemiology, mechanisms of transmission to humans, diagnosis and control.

In each volume, the groups of communicable diseases are listed in alphabetical order, which makes it easy to use. The great asset of this publication is that a number of pages devoted to each disease follows its incidence rate and pathogenicity for humans and animals. Less serious infections are listed briefly while those possessing serious threat are described in great detail. Each chapter is followed by the list of most important references, though some of them are not the most up-to date.

What also makes it easy to use for a reader is the listing of the synonyms for each disease, and chapters divided into paragraphs with headings such as etiology, geographic distribution, occurrence in man and animals, symptoms, sources of infections and mode of transmission, and the role of animals in its epidemiology, diagnosis and control. However, the tables, figures and photographs are included unevenly in the volumes. The transmission cycles are mostly presented in the second volume, while in the third one regarding Parasitoses they are completely missing. And it is in particular in Parasitoses, where the life-cycles are often quite complicated and for a better understanding of the mode of transmission, such illustrations would be very suitable.

What might be rather confusing are a few listed synonyms, which in several cases are somewhat contradictory in terms of their suffixes – osis (-iosis) and -iasis, even if the agents have the same generic suffix – e.g. Balantidiasis versus Balantidiosis (Balantidium coli,) and Cryptosporidiosis (Cryptosporidium spp.).

In conclusion, the publication, primarily targeted at academics and students in schools of public health, medicine and veterinary medicine, researchers as well as the staff of public health and veterinary health institutions, provides an attractive read – not just for everyone who must or wants to be familiar with the subject, but also for all seeking a broad overview in the world of known and emerging zoonoses.

Alveolar echinococcosis (AE) is a zoonotic parasitic diseases caused by a cestode parasite known as Echinococcus multilocularis. The parasite has a wildlife cycle with definitive hosts (foxes) and small mammals as intermediate hosts (rodents) while humans are the accidental hosts. Parasite infection pressure relation to time of the year and age dependent infection pressure for parasite abundance also depend on the urbanization. The aim of current work is forecasting the thresholds via the computational analysis of the disease spread which is a useful approach since it can help to design the experimental settings with better planning and efficiency. Network analysis when interlinked with the computational techniques provides better insight into the spatial and temporal heterogeneities. In the present study, a mathematical framework that describes the transmission dynamics and control measures of E. multilocularis in foxes is documented. We used treatment of foxes with baits for the prevention of the E. multilocularis infection. A novel approach of networking, called Petri net (PN), based on density dependent differential equations, is utilized during this research. The accurate description of the transmission of the parasite and the effect of drug on it is provided to the readers in this article. The transitions, which are difficult to analyse theoretically, are presented with the aid of the discrete approach of networking. A discrete mathematical framework can prove to be an accurate and robust tool to analyse and control the parasite dynamics.

The reproductive effort of Lepeophtheirus pectoralis (Müller O. F., 1776), a caligid copepod, which is commonly found infecting the European flounder, Platichthys flesus (Linnaeus, 1758), is studied in detail for the first time. Seasonal variation in body dimensions and reproductive effort are analysed. Data for 120 ovigerous females, 30 from each season of the year, were considered in the analyses. Females were larger and produced a larger number of smaller eggs in winter, than during the summer. The relationship between egg number and egg size is similar to that recorded for other copepods exploiting fish hosts. Much of the recorded variation was also similar to that reported for a copepod parasitic on an invertebrate host, which suggests the possibility of a general trend in copepod reproduction. Overall, our results provide further support for the hypothesis that there is an alternation of summer and winter generations.

Theileria parva sporozoite stabilates are used in the infection and treatment method of immunization, a widely accepted control option for East Coast fever in cattle. T. parva sporozoites are extracted from infected adult Rhipicephalus appendiculatus ticks either manually, using a pestle and a mortar, or by use of an electric homogenizer. A comparison of the two methods as a function of stabilate infectivity has never been documented. This study was designed to provide a quantitative comparison of stabilates produced by the two methods. The approach was to prepare batches of stabilate by both methods and then subject them to in vitro titration. Equivalence testing was then performed on the average effective doses (ED). The ratio of infective sporozoites yielded by the two methods was found to be 1·14 in favour of the manually ground stabilate with an upper limit of the 95% confidence interval equal to 1·3. We conclude that the choice of method rests more on costs, available infrastructure and standardization than on which method produces a richer sporozoite stabilate.

The poultry red mite, Dermanyssus gallinae, is currently the most common ectoparasite affecting egg-laying hens. Since continuous culture of D. gallinae on birds is a biologically and economically costly endeavour, storage techniques for mites are urgently needed. Effects of temperature on adult and nymph survival were first studied to optimize storage conditions. Then, fecundity of D. gallinae was studied after mites were stored at optimal storage conditions. Results showed the survival rates of protonymphs (42.11%), deutonymphs (8.19%) and females (19.78%) at 5°C after 84 days were higher than those at 0, 25 and 30°C. Thereafter the fecundity and the capability of re-establishing colonies of D. gallinae were evaluated after they were stored for 40 and 80 days at 5°C. After storage, the mean number of eggs showed no statistical difference between treated (5°C for 40 or 80 days) and control groups (25°C for 7 days), while the hatching rates of eggs were in all cases above 97%. The dynamic changes of mite populations and egg numbers showed similar trends to the control group after the stored adult or nymph mites were fed on chicks. Dermanyssus gallinae can be successfully stored at 5°C for 80 days with no interference with the fecundity of mites, and the stored mites could re-establish colonies successfully. Adults and nymphs were two main stages with capability for low temperature storage. These results suggest that low temperature storage is a viable option for colony maintenance of D. gallinae under laboratory conditions.

Phospholipid hydroperoxide glutathione peroxidase (PHGPx, GPx4) is a major antioxidant enzyme, which plays unique roles in the protection of cells against oxidative stress by catalysing reduction of lipid hydroperoxides. We isolated and characterized a full-length cDNA sequence encoding GPx gene from a blood fluke, Schistosoma japonicum (designated SjGPx), which contained an in-frame TGA codon for selenocysteine (Sec) and a concurrent Sec insertion sequence in its 3′-untranslated region. Protein encoded by SjGPx demonstrated a primary structure characteristic to the PHGPx family, including preservation of catalytic domains and absence of the subunit interaction domains. Semi-quantitative reverse transcription PCR and Western blotting showed that the SjGPx was mainly expressed in the female adults and eggs. RNA interference approach was employed to investigate the effects of knockdown of SjGPx. SjGPx expression level was significantly reduced on the 5th day post-RNAi. Significantly reduction in GPx enzyme activities, as well as obvious changes in morphology of intrauterine eggs followed the reduction in SjGPx transcript level. We observed a 63·04% reduction in GPx activity and the eggs severely deformed. Our results revealed that SjGPx protein might be involved in the provision of enzyme activity during egg production.

As shown by RFLP analysis, there is a high variability in the β-tubulin gene region of Leishmania sp. Such variability has been used in the identification of these parasites, establishing differences between subgenera of New World Leishmania. We have found a region of 500 bp (β500) upstream of the coding region of the β-tubulin gene that is present in all strains tested belonging to the L. (Viannia) subgenus. This region apparently is a repetitive sequence and we have shown that it is specific to the Leishmania (Viannia) subgenus. This sequence has no homology with the genomic DNA isolated from either the species belonging to the L. (Leishmania) subgenus or other Kinetoplastida, such as Trypanosoma cruzi, T. brucei, Leptomonas samueli, or Crithidia fasciculata. The β500 sequence showed sufficient variation to be used as a molecular marker in the identification of parasites. We established inter- and intrasubgenus differentiation and were able to discriminate at the species level in the Vianna subgenus. A PCR assay confirmed the specificity of the β500 sequence.

We investigated offspring quality in fleas (Xenopsylla ramesis) feeding on non-reproducing, pregnant or lactating rodents (Meriones crassus) and asked whether (a) quality of flea offspring differs dependent on host reproductive status; (b) fleas trade off offspring quantity for quality; and (c) quality variables are inter-correlated. Emergence success was highest when parents exploited pregnant hosts, while development time was longest when parents exploited lactating hosts. Male offspring from fleas fed on non-reproductive and pregnant hosts were larger than those from lactating hosts whereas female offspring from fleas fed on pregnant hosts were larger than those from both lactating and non-reproductive hosts. Male offspring survived under starvation the longest when their parents exploited lactating hosts and the shortest when their parents exploited pregnant hosts. Female offspring of parents that exploited lactating hosts survived under starvation longer than those that exploited non-reproductive and pregnant hosts. Emergence success and development time decreased as mean number of eggs laid by mothers increased. Fleas that were larger and took longer to develop lived significantly longer under starvation. These results indicate the presence of a trade-off between offspring quantity and quality in fleas exploiting female Sundevall's jird in varying reproductive condition but this trade-off depended on the quality trait considered.

While parasites serve as prey, it is unclear how the spatial distribution of parasite predators provides transmission control and influences patterns of parasitism. Because many of its organisms are sessile, the rocky intertidal zone is a valuable but little used system to understand spatial patterns of parasitism and elucidate the underlying mechanisms driving these patterns. Sea anemones and barnacles are important space competitors in the rocky intertidal zone along the Pacific coast of North America. Anemones are voracious, indiscriminate predators; thus, they may intercept infectious stages of parasites before they reach a host. We investigate whether a sea anemone protects an associated barnacle from parasitism by Hemioniscus balani, an isopod parasitic castrator. At Coal Oil Point, Santa Barbara, California USA, 29% of barnacles were within 1 cm from an anemone at the surveyed tidal height. Barnacles associated with anemones had reduced parasite prevalence and higher reproductive productivity than those remote from sea anemones. In the laboratory, anemones readily consumed the transmission stage of the parasite. Hence, anemone consumption of parasite transmission stages may provide a mechanism by which community context regulates parasite prevalence at a local scale. Our results suggest predation may be an important process providing parasite transmission control.

Oral and subcutaneous administration of the compounds aminopropyl-aminostyrylmethoxyquinoline trihydrochloride and o-β-diethylaminoethyl harmol hydrochloride causes the appearance of peculiar bodies in the blood cells of canaries and mice.

The bodies are irregular in shape and size, stain intensely blue with Leish-man's and Giemsa's stains, and are most numerous in erythrocytes, but occur also in eosinophiles, leucocytes and reticulo-endothelial cells.

The bodies show no cytological structure, are not seen to undergo multiplication, and are not transmissible by blood inoculation.

They are apparently non-living inclusions in the blood cells caused by the action of these two chemical compounds.

The organism, commonly known under the name of the Bottle-bacillus (Flaschen-bacillus; Bacille-bouteille), was first described by Malassez (1874, pp. 203 et seq.), whose observations led him to the following conclusions (p. 211): “Il existe dans la pelade un champignon parasite. Ce champignon occupe les parties les plus superficielles de la couche cornée de l'épiderme; on le trouve entre ou à la surface des cellules épithéliales de cette couche. Il ne se rencontre qu'accidentelle-ment sur les cheveux, et encore siége-t-il sur des cellules épithéliales, qui proviennent de l'épiderme cutané. Il est uniquement constitué par des spores sphériques très-petites.

Both species of tick which are described in the present paper are members of insular faunas and demonstrate remarkably well the tendency, shown by these parasites in geographical isolation, to species formation. In this connexion it is perhaps worth quoting what Cooley & Kohls (1945) say concerning this subject in their recent work on the genus Ixodes: ‘These studies’, they write on p. 1 of their introduction, ‘have revealed in considerable measure the more useful specific characters and the importance of a real appreciation of the significance of geographical range and variation in the differentiation of species.… In determination of species limits we have considered not only morphologic but also biologic factors such as host relationships and geographic distribution. No subspecies are recognized.’ There is little doubt but that geographical distribution will be found to play an almost equally important role in the genus Amblyomma.

1. The male of Rhipicephalus humeralis is redescribed and the female and immature stages are described for the first time. The synonymy of the species is discussed and the various stages are compared with those of R. pulchellus.

2. Details of the life cycle under laboratory conditions are given.

3. The host list and distribution of the species are given.

When beginning this investigation it was my intention to make a comparison between the anatomy of the apterous viviparous form and that of the winged viviparous form, to ascertain what differences were present corresponding with the difference in habit of the Aphis in these two stages. I found, however, that the literature bearing on the group to which S. rosarum belongs, was somewhat scanty, and as a rule, rather out of date. It therefore became necessary, before undertaking the comparative work, to obtain a somewhat more complete account of the general anatomy. It is with this idea in view that the following paper has been written; but, as will be seen on perusing it, much more attention has been given to the internal anatomy than to the external parts. It is my intention, now that this first part of the task is completed, to take up my original project. I desire to take this opportunity of expressing my gratitude to Professor Bridge, Mr A. E. Shipley, F.R.S., Mr Doncaster and Mr Collinge for the valuable assistance and advice they have given me whilst this work has been in progress.

Environmental fluctuations are expected to require special adaptations only if they are associated with a decrease in fitness. We compared reproductive performance between fleas fed on alternating (preferred and non-preferred) hosts and fleas fed solely on either a preferred or a non-preferred host to determine whether (1) host alternation incurs an immediate negative effect, and, if yes, then (2) whether this effect is greater in a host specialist (Parapulex chephrenis) than in host generalists (Xenopsylla conformis and Synosternus cleopatrae). We also compared flea performance under alternating host regimes with different host order (initial feeding on either a preferred or a non-preferred host). An immediate negative effect of alternating hosts on reproductive performance was found in P. chephrenis only. These fleas produced 44·3% less eggs that were 3·6% smaller when they fed on alternating hosts as compared with a preferred host. In contrast, X. conformis and S. cleopatrae appeared to be able to adapt their reproductive strategy to host alternation by producing higher quality offspring (on average, 3·1% faster development and 2·1% larger size) without compromising offspring number. However, the former produced eggs that were slightly, albeit significantly, smaller when it fed on alternating hosts as compared with a preferred host. Moreover, host order affected reproductive performance in host generalists (e.g. 2·8% larger eggs when the first feeding was performed on a non-preferred host), but not in a host specialist. We conclude that immediate effects of environmental fluctuation on parasite fitness depend on the degree of host specialization.

As a consequence of axenic growth and the elimination of accompanying bacterial flora, Entamoeba histolytica virulence decreases rapidly, and pathogenicity is lost. This paper evaluated the impact of vitamin supplementation on the pathogenicity of E. histolytica. Growth of E. histolytica trophozoites, cultured axenically in PEHPS (a Spanish acronym for the main ingredients – casein peptone, liver, pancreas extract and bovine serum) medium, with or without vitamins, exhibited a similar growth rate. However, the vitamin-enriched PEHPS preparations expressed 2.65 times more haemolytic activity (at 60 min: 98 vs 48%, P < 0.05), 2.5 times more phospholipase A2 activity at 150 min of incubation and generated more hepatic abscesses (88 vs 60%, P = 0.05) than the preparations without vitamins. The haemolytic and phospholipase A2 activity for the PEHPS − V preparations were restored following vitamin supplementation with A and D. These data highlight, for the first time, that vitamins and specifically vitamin A and D were essential for the recovery of amoebic virulence, lost through axenic growth.

Male: Large, 4·00–7–75 mm. long. Salient features: Inornate; basis capituli nearly twice as broad as long; lateral angles within the anterior third and rather acute. Anterior coxae slightly prominent in dorsal view. Lateral grooves well-marked and including two festoons. Dorsal furrows distinct, the lateral somewhat comma-shaped, the median straight and continued anteriorly beyond the laterals. Punctations very numerous, usually discreet and equal in the median area which appears shagreened; few on the scapulae, lateral folds and festoons, which form a glossy border. Adanal plates with straight external border and broad, rounded posterior border; internal border slightly concave to where it joins the posterior border to form a small point in a number of specimens. Accessory plates distinct. Spiracle short with slight dorsal curve.