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The importation of malaria into a region where it is not endemic raises many concerns, including the timely delivery of appropriate care, safety of the blood supply, and the risk of autochthonous transmission. There is presently no consensus on the best way to screen mobile populations for malaria. Between August 2000 and March 2001, 535 refugees arrived in Quebec, Canada, from Tanzanian camps. Within 4 weeks of resettlement of the first group of 224, the McGill University Centre for Tropical Diseases noted an outbreak of malaria across the province (15 cases over a 3-week period). This group (group 1) was traced and screened for malaria between 3 and 4 months after arrival in Canada. Subsequent groups of 106 and 205 refugees were screened immediately upon arrival in Canada (group 2) and immediately prior to their departure from refugee camps (group 3), respectively. A single EDTA-blood sample was obtained from 521 refugees for testing by thick and thin blood smears (groups 1 and 2), antigen detection (ICT Malaria Pf and OptiMAL; group 1 only), and nested PCR (all groups). Overall, 98 of 521 refugees were found to be infected (18.8%). The vast majority of infections (81 of 98) were caused by Plasmodium falciparum alone. Using PCR as the "gold standard," both microscopy (sensitivity, 50%; specificity, 100%) and antigen detection (ICT sensitivity, 37.5%; ICT specificity, 100%; OptiMAL sensitivity, 29.1%; OptiMAL specificity, 95.6%) performed poorly. None of the PCR-positive subjects were symptomatic at the time of testing, and only two had recently had symptoms compatible with malaria (with or without diagnosis and treatment). Active surveillance of migrants from regions of intense malaria transmission can reduce the risk of morbidity in the migrant population and mitigate against transmission to the host population. Our data demonstrate that PCR is, by far, the most powerful tool for such surveillance.

Three enzyme immunoassays (EIAs) for diagnosis of Chagas' disease were developed with fixed forms of Trypanosoma cruzi using a panel of 435 sera from the following groups: Venezuelan subjects positive by immunofluorescence (n = 70), Venezuelan healthy controls (n = 85), healthy Canadians (n = 166), and subjects with other parasitic diseases (n = 114). All assays achieved 100% sensitivity and reasonable specificity for amastigotes (97.6%), epimastigotes (98.3%), and trypomastigotes (99.3%). The fixed-trypomastigote assay was stable over 4 months at 4 degrees C and room temperature. These data suggest that a fixed-trypomastigote EIA may be a suitable candidate for blood bank screening.

Indirect ELISAs using denatured antigen preparations of Trypanosoma (T.) congolense (TcAGd) and T. vivax (TvAGd) for detection of anti-trypanosome antibodies in bovine serum (I-TAB ELISAs), were adapted for serodiagnosis in goats. The diagnostic proficiency, the cross-reactivity with sera from heterologous trypanosome infections and the operational performance of the assays were evaluated on experimentally trypanosome-infected goats. The I-TAB ELISA (TcAGd) detected antibodies in all T. congolense infected goats (100% overall sensitivity) from 2 to 4 weeks post-infection (p.i.) until the end of the experiments. Specificity tested on 92 uninfected goats was 96.7%. Extensive cross-reactions of I-TAB ELISA (TcAGd) with sera from T. vivax or T. brucei infected goats were observed. The I-TAB ELISA (TvAGd) detected antibodies in 5 of the 6 T. vivax infected goats, specificity tested on uninfected goats was 100%. Cross-reactivity with sera from T. congolense or T. brucei infected goats remained limited. Infecting species identification based on the highest percent positivity (PP) in both systems, correctly identified all T. congolense infections, but misidentified in 2/19 occasions a T. vivax infection as a T. congolense infection. In the absence of T. brucei specific antigen coated plates, T. brucei infections were identified in, respectively, 7/9 and 2/9 occasions as T. congolense or T. vivax infections. Acceptable inter-plate repeatability was observed. The implications of results and technical requirements for ongoing applied research are discussed.

Background and Purpose: Wild-caught New World monkeys (NWM) from Central or South America are often infected with Trypanosoma species, including T. cruzi. In humans, T. cruzi causes Chagas' disease. Even in closed monkey colonies, T. cruzi can be propagated by blood-to-blood exposure, sexual activity, and transplacental transmission. Animal handlers and laboratory staff who deal with blood and tissues from infected NWM are at riskfor acquiring Chagas' disease via accidental exposure., Methods: We screened 162 blood samples from wild-caught Saimiri sp. monkeys for Trypanosoma species infections by use of blood smear examination, ELISA, and polymerase chain reaction (PCR) analysis. Blood samples from 19 employees with recent history of monkey-associated injuries also were tested., Results: Six percent (10/162) of the monkey samples were T. cruzi positive on the basis of blood smear examination results, 10.4% (17/162) were positive by ELISA results, and 26.5% (43/162) were positive by PCR results. Other organisms identified by PCR analysis included T. rangeli in two animals, Plasmodium spp. in two animals (P. malariae confirmed by PCR results) and microfilariae in one animal (morphologically, Mansonella perstans). Evidence of trypanosome infection was not found in the 19 employee samples on the basis of results of any of the three aforementioned tests., Conclusions: Close attention must be paid to worker safety where wild-caught NWM are used. The PCR analysis has a clear advantage over conventional techniques (ELISA, blood smear) for screening NWM for trypanosome infections during quarantine and after employee injury.

The authors described the first cases in Senegal (West Africa) of the association Parkinson's disease and epilepsy. Almost studies on this feature, stressed on their different pathophysiology basis epilepsy is related on excess of neuronal excitation, and Parkinson disease is an expression of lack of motor neuromodulation. The diagnosis has been done because of the coming out two seizures in the year on two patients one 59 years old and the other 70 years old experiencing Parkinson disease well documented before and treated. Biological study, ultrasonography and Doppler, CT Scan lead to rule out a vasculopathy. Good outcome with antiparkinsonian and anticonvulsant medications confirm the diagnosis.

The buffy coat of 76 roaming goats from the Bansang and Missira regions in Gambia, was examined for the presence of trypanosomes. From these animals, extractions from dry blood samples on filter paper were subjected to PCR using three different primer sets, ORPHON5J, GOL and TVW, specific for Trypanosoma brucei/Trypanosoma evansi, Trypanosoma congolense and Trypanosoma vivax, respectively. PCR results for T. congolense were 100% concordant with buffy coat examination. Besides the three T. vivax buffy coat-positive samples, another 15 yielded positive with the TVW primers. The ORPHON5J primers yielded no positive results. Analyses with the GOL primers of putatively negative samples, yielded aberrant band patterns whose diagnostic significance still remains to be determined.

In seven goats experimentally infected with a pleomorphic clone of Trypanosoma brucei brucei, parasitaemia was monitored weekly for 6 weeks by wet blood film and microhaematocrit buffy coat examination. Dried blood samples on filter paper were concomitantly collected and tested by PCR using three different primer sets, putatively specific for Trypanozoon, T. vivax and T. congolense. With the originally designed ORPHON5J Trypanozoon primers, PCR tests became positive after 1 week (six animals) or 2 weeks (one animal) of infection and remained consistently positive until the end of the experiments, thus yielding an overall positivity rate of 97%, as compared with 74% for all parasitological tests together. The T. vivax and T. congolense primers yielded no positive PCR results.

Six goats were experimentally infected with a stock of Trypanosoma vivax. Parasitaemia was weekly monitored by buffy coat and wet blood film examination during a period of 15 weeks and another 3 weeks following drug-treatment. Dried blood samples were tested by the polymerase chain reaction (PCR), using an extraction method with Chelex 100 (BioRad). PCR proved consistently more sensitive than the parasitological techniques.

Markers for acute hepatitis A, B, C and E virus infections were examined in the sera of 72 patients suffering from acute hepatitis in Senegal and Tunisia. Hepatitis B was responsible for 36% and hepatitis C for 21% of the cases. Acute hepatitis A was not diagnosed. HEV infection was not observed in Senegal and represents only 4% of the acute hepatitis cases in Tunisia.

An epidemiological survey on gastrointestinal helminthiasis in 51 sheep and 51 goats was held in the tree-cropping pasture region in Senegal from October 1990 to September 1991. All the animals examined were infected with at least 1 helminth species. Three trematodes (Fasciola gigantica, Schistosoma bovis, Amphistomatids), 2 cestodes (Moniezia expansa, Cysticercus tenuicollis) and 9 nematodes were identified. The most important parasite in sheep was Haemonchus contortus while Trichostrongylus colubriformis predominated in goats. The worm burden in sheep was significantly higher than in goats (P < 0.001). L4 larvae of H contortus were found in 85-87% of the small ruminants. There was a negative correlation between haematocrit, number of worms and egg per gram of faeces during the rainy season. These results show that the gastrointestinal nematode burden is high during the rainy season. During the dry season (9 months) nutritional problems are aggravated by adult worms and residual larvae.

A retrospective case control study is underdone in Infections Diseases Service of Dakar (Senegal) from june 1 st, 1989 to december 31 st, 1989. 203 observations are collected on the basis of positive blood stream and blood films with Plasmodium falciparum. The authors give the epidemiological picture of the two clinical features which are: Malignant tertian (107 cases-53%) and intermittent access (96 cases-47%). Lethal risk is 12 fold higher in Malignant tertian form than in the intermittent one. Parasitemia median is below 5,000 parasites/mm3. There is no relation between parasite density and clinical pictures. Thus, they advance tumor necrosis factor's in the pathogenia as others authors did and its impact in vital prognostic.

The human rabies is a dangerous disease with fatal evolution. We report in this study, 33 cases of human rabies admitted in the Infectious Diseases Clinic CHU Fann Dakar, on january 1980 through december 1990. The development of the disease in our country depends on the existence of stray dogs and deficient informations of the population about this endemic. It is therefore necessary to insist on the health care education of populations, the campaign against dogs rabies, the formation of medical and paramedical health care personnel and the creation of decentralized antirabies centers.

Systematic, non-suppurate, acute pneumopathies (PANSS) or acute, clear-cut, lobary pneumonia (PFLA) constitute a pathology in babies aged 0-1 years. The clinic found 83.3% of these little patients to be feverish, dyspneic and suffering from a dry cough. 85% of the cases presented the alveolary filling syndrome with acric bronchogramme. After a 3 day apyrexy period on penicillin, the evolution was favourable in 83.4% of the cases.

The authors point out that, after tetanus, purulent meningitis is a very common neo-natal infection. Their epidemiology is dominated by the existence of particular obstetric and associated factors, which play an important role in the early development of this sickness. Numerous forms of bacteria, particularly pneumococci, were isolated. In spite of everything, the mortality rate is high, so attention should be given to preventing this illness. Better follow-up during pregnancy coupled with better conditions for delivery could help this prophylaxis.