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Myiasis is the infestation of vertebrate tissues with fly larvae (Diptera). Most human cases in North America are subcutaneous forms due to Dermatobia hominis imported from Central and South America. Human cases of myiasis acquired in North America are rare and are primarily subdermal or ophthalmologic forms of infestation caused by early stages of Cuterebra larvae. We report an unusual case of tracheopulmonary myiasis, resulting from the in situ development of a mature cuterebrine larva associated with high eosinophilia. Only two other cases of tracheopulmonary cuterebrid myiasis have been reported in humans, and they are reviewed herein. Cuterebra myiasis (cuterebrosis) remains a rare and aberrant cause of tracheopulmonary disease and is a newly described cause of eosinophilia in humans.

During the period of major tick activity, in April and May 1998, in the Saint-Maixent l'Ecole area of Poitou, a comparative study was carried out in order to evaluate the protective effect of garments impregnated with permethrin cis/trans 25/75. Three groups of soldiers made up respectively of 208, 218 and 427 men were involved for 2 or 3 days in this experiment. Respectively 107, 107 and 215 wore impregnated uniforms. Out of a total of 319 ticks, 3 were lxodes ricinus, 305 Dermacentor marginatus and 11 D. reticulatus. There was a significant difference in both the intensity (number of ticks per individual, P < 0.0001) and prevalence (number of individuals with ticks, P < 0.001) of ticks on individuals between impregnated and non impregnated uniforms. The repellent effect of permethrin on ticks was observed at the site of preferential tick attachment (normally the head of the host for these two species of Dermacentor in France) where the number of ticks was significantly lower in impregnated uniforms.

Background: Human urinary myiasis is caused by fly larvae which complete their entire cycle in the human body., Case Report: A 37-year-old woman living in a village near Sidi Bel Abbes (Algeria) developed a parasite syndrome caused by Fannia canicularis larvae. About twenty larvae specimens were collected during her hospitalization. Larvae were emitted for 2 weeks after a 6-day treatment with cefotaxime for urinary tract infection., Discussion: Urogenital myiasis is almost always subsequent to conditions of poor personal hygiene. In this case authentic larvae infestation was evidenced. The diagnosis of true urinary myiasis was confirmed by repeated emissions of different larval stages including the nymph.

The Rambouillet Forest, a Lyme disease-endemic area near Paris, France, was surveyed from September 1994 to October 1995 to determine the risk periods and zones for humans. Firstly, during the period of Ixodes ricinus activity, abundance of nymphs is greater in spring than in autumn. Secondly, we observed significant variation in nymphal abundance between zones according to the density of cervids. The polymerase chain reaction (PCR) was used to detect DNA of Borrelia burgdorferi sensu lato in 461 unfed nymphs. DNA was detected in 38 nymphs (8.2%). By genospecific PCR based on the OspA gene, we detected the three pathogenic spirochetes with occurrences of 10.3, 31.1 and 58.6 for B. burgdorferi s.s., Borrelia garinii and Borrelia afzelii, respectively, indicating that B. afzelii is probably the main Borrelia species in the Rambouillet Forest. Finally, 11.5% of positive nymphs exhibited a double infection. Infection rates of I. ricinus nymphs by B. burgdorferi s.l. were not significantly different throughout the year for a given area, indicating that the risk periods of acquiring Lyme disease are mainly linked to nymph activity and correspond to spring and autumn. Likewise infection rates of nymphs were not significantly different between zones with a high density of deer (more than 100 animals per 100 ha) and zones with lower deer density (less than 20 animals per 100 ha). In addition to the role of deer as an amplifier of tick populations, these data indicate that zones with a high density of cervids should be considered as higher risk areas.

After a short historical presentation of the discovery of the pathogen and its vector, the authors present the current data on bacterial and acarologic taxonomy. Then they describe their results to assess the mechanisms of circulation of the bacteria in the forests of Ile-de-France, particularly in the forest of Rambouillet. The combined study of abundance and infection frequency of the vectors, small mammals and cervids leads to the characterization of periods and areas of higher risk. The risk periods correlate with high density of I. ricinus nymphs. The risk areas correspond to those of high density of cervids. The role of reservoir of small mammals is confirmed, to the one of large mammals, so debated, is clearly demonstrated.

In Algeria, Human myiasis, essentially ophtalmomyiasis, are known for a long time. Most of cases are due to Oestrus ovis. In this papers the authors report, in a shepherd, the first case of otomyiasis due to Chrysomya bezziana larvae, a species still unknown in North Africa. This observation which indicates the presence of the species in a Northern part of Algeria is also the first report of the insect outside of its endemic traditional area.

Free-living nymphs and adults from Rambouillet and Fontainebleau, 2 major forests of Ile de France, were collected to determine the infection rates of Ixodes ricinus L. by Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt & Brenner). Field-collected I. ricinus nymphs and adults were screened for the presence of B. burgdorferi using direct fluorescent antibody assay. The infection rates of nymph, male and female were 12.4% (314), 2.8% (35), and 2.9% (34). No difference in infection rates of nymphs among sites were detected. Spirochetes was isolated from both sites. Isolates from Rambouillet and Fontainebleau were identified as B. burgdorferi sensu stricto and B. garinii, respectively (Baranton, Postic, Saint-Girons, Boerlin, Piffaretti, Assous, and Grimont).

This study, dealing with two strains of Aedes aegypti from Vietnam and French Guiana, shows the variability of the genes coding for 11 isoenzymatic systems and the replication of the dengue 2 virus in parenterally infected mosquitoes. Slight differences are observed in the characteristics of viral replication. No clear correlation is shown with enzymatic patterns which appear widely different from one strain to the other with four of the enzymes studied.

Lyme disease, known primarily from North America, with three main foci in the United States, and from temperate Europe, particularly in France, seems to be increasing in incidence. Wherever it is known to exist, it has become the most prevalent tick-borne disease of man. The natural cycle of the etiologic agent, Borrelia burgdorferi, involves ticks as vectors and wild rodents as reservoirs. In infected areas, everyone walking or, especially, working in forested areas is at risk of tick bites, especially from May to October.