Diagnostic accuracy of swine echinococcosis cytopathological tests and challenges for a differential diagnosis: slaughterhouse data.

Echinococcosis disease shows clinical signs similar to many diseases. Hence we report cases that need to be confirmed using appropriate tests. A confirmatory study has been conducted to assess the accuracy of two cytopathological tests, with the histopathology test as the reference standard. The first cytopathological test evaluates the Ziehl Neelsen staining with an epifluorescence microscope (cytopath 1). The second cytopathological test uses the same staining followed by a transmitted light microscope examination (cytopath 2). Of a total of 2524 inspected pigs, 101 suspected cases of echinococcosis were detected, of which 67 were found positive with the two cytopathological tests and the histopathological one. The specificity of cytopath 1 (100 % [95 % CI 100 - 100]) and cytopath 2 (100 % [95 % CI 100;100]) were similar, as well as their respective positive predictive values: 100 % [95 % CI 100 - 100] vs. 100 % [95 % CI 100 - 100]. The sensitivity of cytopath 1 is 79.66 % [95 % CI 69.39 - 89.93], while cytopath 2 equals 66.10 % [95 % CI 54.02 - 78.18]. The difference in sensitivity of both tests was not significant. Negative predictive values found for cytopath 1, and cytopath 2 were 40 [95 % CI 18.53 - 61.47] and 28.57 [95 % CI 11.84 - 45.3], leading to the Generalized Estimating Equations (GEE) Model estimate for an odds ratio of 1.4 [95 % CI 0.41 - 5.2], p = 0.06. Cytopath 1 and cytopath 2 are equivalent in terms of specificity (100 % [95 % CI 100 - 100] vs. 100 % [95 % CI 100;100]) and positive predictive value (100 % [95 % CI 100 - 100]. Cytopath 1 is more sensitive than cytopath 2 but not significant (79.66 % [ 95 % CI 69.39 - 89.93] vs. 66.10 % [95 % CI 54.02 - 78.18]). However, the negative predictive value of cytopath 1 is better than that of cytopath 2: 40 % [95 % CI 18.53 - 61.47] vs. 28.57 % [95 % CI 11.84 - 45.3].

A survey of intestinal helminths in domestic dogs in a human-animal-environmental interface: the Oloisukut Conservancy, Narok County, Kenya.

Dogs living in a domestic-wildlife interface can serve as reservoirs and sentinels of parasites shared among humans, domestic animals and wildlife. In Kenya, the epidemiology of intestinal parasites of dogs and their role as reservoirs of zoonoses is poorly understood, especially in domestic-wildlife interfaces. This study aimed to determine the occurrence of intestinal helminths in domestic dogs in the Oloisukut Conservancy. One hundred dog faecal samples were collected per rectum and examined microscopically following zinc chloride flotation and formal-ether concentration techniques. Genotyping of helminths was achieved by nested polymerase chain reaction of NADH dehydrogenase subunit 1, cytochrome oxidase 1 and partial sequencing. Nine genera were detected by microscopy in 65 (65%) dog faecal samples from 54/76 (71.05%) households. The most frequent helminths were hookworm (39%), Spirometra spp. (17%), taeniids (13%), Toxocara spp. (10%), Trichuris spp. (10%), Spirocerca lupi (5%), Physaloptera spp. (2%), Dipylidium caninum (1%) and Strongyloides spp. (1%). Ancylostoma caninum was the only hookworm species detected in dogs, while Taenia serialis and Taenia madoquae were detected in four and one faecal samples, respectively. This study reports for the first time the molecular detection of the cestodes Spirometra theileri, D. caninum and Mesocestoides sp. in dogs in Kenya. The presence of zoonotic helminths in dogs indicates that the residents of this conservancy are exposed to public health risks. The helminths reported here confirm the interaction of domestic dogs with wildlife. An integrated control programme involving the medical, veterinary and wildlife conservation professionals is needed to avert transmission of infectious diseases to humans, domestic animals and wildlife.

The natural history of cystic echinococcosis in untreated and albendazole-treated patients.

The World Health Organization (WHO) treatment protocols for cystic echinococcosis (CE) are based on the standardized ultrasound (US) classification. This study examined whether the classification reflected the natural history of CE in untreated and albendazole-treated patients. Data were collected during mass US screenings in CE endemic regions among transhumant populations, the Turkana and Berber peoples of Kenya and Morocco. Cysts were classified using the WHO classification. Patient records occurring prior to treatment, and after albendazole administration, were selected. 852 paired before/after observations of 360 cysts from 257 patients were analyzed. A McNemar-Bowker χ2 test for symmetry was significant (p<0.0001). 744 observations (87.3%) maintained the same class, and 101 (11.9%) progressed, consistent with the classification. Regression to CE3B occurred in seven of 116 CE4 cyst observations (6.0%). A McNemar-Bowker χ2 test of 1414 paired before/after observations of 288 cysts from 157 albendazole-treated patients was significant (p<0.0001). 1236 observations (87.4%) maintained the same class, and 149 (10.5%) progressed, consistent with the classification. Regression to CE3B occurred in 29 of 206 CE4 observations (14.1%). Significant asymmetry confirms the WHO classification's applicability to the natural history of CE and albendazole-induced changes. Regressions may reflect the stability of CE3B cysts.

Gonadal steroids differentially modulate the actions of orphanin FQ/nociceptin at a physiologically relevant circuit controlling female sexual receptivity.

Orphanin FQ/nociceptin (OFQ/N) inhibits the activity of pro-opiomelanocortin (POMC) neurones located in the hypothalamic arcuate nucleus (ARH) that regulate female sexual behaviour and energy balance. We tested the hypothesis that gonadal steroids differentially modulate the ability of OFQ/N to inhibit these cells via presynaptic inhibition of transmitter release and postsynaptic activation of G protein-gated, inwardly-rectifying K(+) (GIRK)-1 channels. Whole-cell patch clamp recordings were performed in hypothalamic slices prepared from ovariectomised rats. OFQ/N (1 µm) decreased the frequency of miniature excitatory postsynaptic currents (mEPSCs) and miniature inhibitory postsynaptic currents (mIPSCs), and also caused a robust outward current in the presence of tetrodotoxin, in ARH neurones from vehicle-treated animals. A priming dose of oestradiol benzoate (EB; 2 µg) increased basal mEPSC frequency, markedly diminished both the OFQ/N-induced decrease in mEPSC frequency and the activation of GIRK-1 currents, and potentiated the OFQ/N-induced decrease in mIPSC frequency. Steroid treatment regimens that facilitate sexual receptivity reinstate the basal mEPSC frequency, the OFQ/N-induced decrease in mEPSC frequency and the activation of GIRK-1 currents to levels observed in vehicle-treated controls, and largely abolish the ability of OFQ/N to decrease mIPSC frequency. These effects were observed in an appreciable population of identified POMC neurones, almost one-half of which projected to the medial preoptic nucleus. Taken together, these data reveal that gonadal steroids influence the pleiotropic actions of OFQ/N on ARH neurones, including POMC neurones, in a disparate manner. These temporal changes in OFQ/N responsiveness further implicate this neuropeptide system as a critical mediator of the gonadal steroid regulation of reproductive behaviour.

Cystic echinococcosis in the Berber of the Mid Atlas mountains, Morocco: new insights into the natural history of the disease in humans.

Precise knowledge of the natural history of cystic echinococcosis (CE) in humans remains somewhat arcane. The aim of the present study was to determine whether aspects of the natural history of established human infection with Echinococcus granulosus could be investigated by using a cross-sectional approach, in a community where CE was endemic. A mass ultrasound-screening survey, coupled with a questionnaire to record all previous surgical histories related to CE, was carried out amongst the primarily transhumant Berber people of the Mid Atlas mountains in Morocco. During two periods of intensive screening, of 10 days in May 2000 and 11 days in May 2001, 11,612 people, representing > 98% of the local population, were checked. One hundred and twenty six (1.1%) of the subjects--75 (59.5%) of the 6864 females investigated and 51 (40.5%) of the 4748 males--were found ultrasound-positive for CE. Overall, 14.1% of the CE cases detected were children aged 1-15 years (who made up 44% of the study population). Most (77.4%) of the ultrasound-positive subjects investigated were also found seropositive for CE. The frequency of a past history of surgery for CE increased with subject age (P = 0.024), 125 (1.1%) of the subjects being recorded as having had such surgery. The frequency of surgery for pulmonary CE was relatively constant in all age-groups, indicating that infection can occur at any time. The frequency of abdominal CE increased with age (R2 = 0.8102). Assuming that the incidence of infection remains fairly constant over time and that the longer a person spends in this endemic area the more likely it is that he or she will develop CE, then a progression from active through transitional to inactive CE should occur. The cysts observed by ultrasound in the present study were categorized, as type 1, 2, 3, 4 or 5, according to the new, standardized, ultrasound classification of CE developed by the World Health Organization (WHO). There was a clear exponential decline in the frequency of the various cyst types, from type 1 (the most frequent) to type 5 (the rarest). This decline validates the assumptions made, about the natural history of established CE, by those who developed the WHO's classification. The classification should therefore be invaluable to surgeons and clinicians, when they have to consider treatment options for patients with the various types of CE, and to policy makers trying to establish the economic costs of treating CE in endemic settings.

Public health education/importance and experience from the field. Educational impact of community-based ultrasound screening surveys.

The public health educational impact of community-based ultrasound (US) surveys for cystic echinococcosis (CE) can form an important part of the development about the awareness of the importance of the disease in an endemic area. In addition to identifying asymptomatic carriers and thereby facilitating early diagnosis and treatment, such surveys can be used to impart important educational messages at the individual, household, community, regional and national levels. US surveys are usually appealing to rural communities where such services are not available but where the technique is generally appreciated by its application in a wide field of medical applications. The qualities of the test (painless, non-invasive and gives instant recordable results) are also attractive to participants during such surveys and the majority of the population in a selected study area choose to be screened. Two such surveys were carried out amongst the Berber people of the mid-Atlas mountains in central Morocco in May 2000 and 2001. Over 11,000 people were screened in the two 10-day surveys. Informed consent had been obtained through community meetings and with the chiefs of villages prior to the surveys being conducted. Individuals who volunteered to be screened entered the study and as far as is known there were no refusals. The concept of voluntary participation, the explanation of the life cycle and clinical manifestations of the disease and its prevention are all-important educational messages. The occurrence of CE is almost always known in an endemic community but is usually very poorly understood leading in many cases to a fear of the disease, especially amongst families with an infected individual who has previously undergone surgery. During the US survey considerable attention was paid to provide educational input before, during and after the survey. Information was provided at the start of the survey to local leaders, doctors, veterinarians and school teachers on the aims of the study and to obtain informed consent. At the start of the study everyone was individually schooled about the route of transmission of the parasite and how this may be best prevented. The knowledge level of those screened was assessed by showing hydatid cysts, either freshly obtained from the abattoir of from photographs. Animal cysts were recognised by almost everyone but its transmission and link to human disease was invariably unknown. Patients found to be infected with CE were always confidentially counselled and followed up for treatment, if required. Treatment options were explained to the individual or to parents in the case of a child. Local physicians participated in discussions on the WHO guidelines for the treatment of CE and all cases were fully discussed providing an educational element for the local doctors. The 1% US prevalence found sent an important message to the local politicians and the perceived importance of the disease had an impact at the leadership level. Local leaders made calls for a control programme. The long term educational impact remains to be evaluated as does the role such surveys play in the future collaboration of communities with the implementation of a control programme.

Common and stage-specific antigens of Theileria annulata.

Western blot analysis of Theileria annulata antigens was carried out using sera collected from cattle which had been immunised and challenged with either T. annulata sporozoites or schizont-infected cells. Three antigens between 71 and 73 kDa proved to be common to the three stages of parasite studied: sporozoites, schizonts and piroplasms. An antigen was found at 32 kDa which was specific to T. annulata piroplasms. Results were reproducible using sera from Morocco and the UK. At least one of the proteins at 71-73 kDa, but not that at 32 kDa were also recognised by sera from animals infected with Babesia species.

Anti-lymphocyte antibodies generated in animals immunised with Theileria annulata-infected cells.

Complement fixing antibodies were measured in sera from animals immunised with either Theileria annulata sporozoites or autologous or allogeneic schizont-infected mononuclear cells using a complement-mediated micro-cytotoxicity test. The test demonstrated the presence of anti-lymphocyte antibodies in allogeneic cell-immunised animals, which were not detectable in autologous cell- or sporozoite-immunised animals; also that these antibodies were directed to T. annulata-infected and (MHC) class I antigens. Their potential importance in repeated immunisations is discussed.

Stage-specific responses following infection with Theileria annulata as evaluated using ELISA.

An enzyme-linked immunosorbent assay (ELISA) using sporozoite, schizont and piroplasm antigens was developed to study the immune response of animals that had been immunised with either Theileria annulata sporozoites or schizont-infected cells and then challenged with sporozoites. The aim was to identify the most suitable antigen for a routine screening test and to compare the sensitivity of the latter with that of the indirect fluorescent antibody test (IFAT). As determined by ELISA, cattle produced antibodies to all three antigens, regardless of the method of immunisation. The schizont antigen was the least sensitive, whereas the sporozoite antigen displayed high pre-inoculation values. In contrast, the piroplasm antigen exhibited low non-specific pre-infection levels and high post-immunisation and post-challenge values according to both ELISA and IFAT. Therefore, the latter was though to be the most appropriate antigen for use in ELISA.