[Cercarial dermatitis in Europe: a new public health problem?]. / La dermatite cercarienne en Europe: un problème de santé publique nouveau?

Cercarial dermatitis is a parasitic impasse that has worldwide distribution. The condition manifests itself as a highly pruriginous skin rash and is due to penetration of the dermis by larval stages (furcocercariae) of avian trematodes. Many species may be responsible for this disease. In Europe the genus Trichobilharzia is widely represented, in particular by the species T. ocellata; the definitive host is the duck (Anas platyrhinchos); the intermediate hosts are snails of the genus Lymnea (L. ovata or L. stagnalis). In France, cases of cercarial dermatitis were reported in June and July 1994 to the health authorities of three départements in the Pays de la Loire Region (western France). The epidemiological situation, common to the three maintained ponds that were concerned, is as follows: high level of eutrophication of the sites, colonization of the ponds by L. ovata, and settlement by many duck colonies. The simultaneous occurrence of these three phenomena, combined with long hours of sunshine in the summer, is responsible for most of the foci of cercarial dermatitis recently described in Europe. Control of this condition is difficult, requiring strict maintenance of bodies of water and if necessary the use of molluscicides such as niclosamide. The use of praziquantel in baits for treating the definitive hosts appears to interrupt the natural cycle of the avian Schistosomatidae. In the light of the observations reported here and the analysis of recent publications, cercarial dermatitis may be regarded as an emerging disease. Its public health impact needs to be evaluated at the global level.

Speed of skin penetration and initial migration route of infective larvae of Schistosoma haematobium in Meriones unguiculatus.

The kinetics of skin penetration of Schistosoma haematobium (Bilharz, 1852) (Trematoda, Schistosomatidae) cercariae is reported for the first time, Meriones unguiculatus (Rodent, Gerbillidae) being used as experimental model. It has been demonstrated that the cercariae cross the epidermis of their hosts either directly or through hair follicles culs-de-sac from 3 to 5 min. The corresponding schistosomulae slide into the superficial part of the dermis or move along the base of hair follicles. Six minutes after, schistosomulae are found in the lumen of lymphatic vessels running alongside blood capillaries. One hour post-infestation, the dermis presents acute inflammatory reaction with edema, infiltration of neutrophil and eosinophil leukocytes. Conversely, dilated blood capillaries do not contain any schistosomula. Thus, the initial migration path of infective larvae of S. haematobium in M. unguiculatus is lymphatic.

[The campaign against schistosomiasis]. / La lutte contre les schistosomiases.

Like other diseases linked to environment from where men look for supplies of goods, schistosomiases are difficult to control. Means of control are existing (mass treatment, selective treatment, with well tolerated drugs) but to insure the decrease of the prevalence over a long period of time, the strategies are sophisticated and often expensive. Therefore, today the objectives of schistosomiasis control are focused on the prevention and decrease of morbidity rather than on the decrease of transmission. Especially so when the economic, social and cultural levels do not permit to avoid the "pathogenic" behaviours.

Holochilus brasiliensis and Nectomys squamipes (Rodentia-Cricetidae) natural hosts of Schistosoma mansoni.

After several Brazilian researchers, the author examines the capacity of two species of rodents Cricetidae, Holochilus brasiliensis and Nectomys squamipes, to maintain the biological cycle of Schistosoma mansoni in the field and to be parasite reservoir: (a) the role they are able to play in human endemy; (b) the methods necessary to characterize the population of Schistosoma mansoni related either to man, either to rodents, either to both.

Holochilus brasiliensis and nectomys squamipes (Rodentia-Cricetidae) natural hosts of Schistosoma mansoni

After several Brazilian researches, the author examines the capacity of two species of rodents Cricetidae, Holochilus brasiliensis and Nectomys squamipes, to maintain the biological cycle of Schistosoma mansoni in the field and to be parasite reservoir: (a) the role they are able to play in human endemy; (b) the methods necessary to characterize the population of Schistosoma mansoni related either to man, either to rodents, either to both

[Chaetotaxy of the cercaria of Paramphistomum sp., a parasite of cattle in Vendée]. / Chétotaxie de la cercaire de Paramphistomum sp. parasite du bétail en Vendée.

The cercaria was shed by an Anisus rotundatus experimentally infected with a parasite of Bos taurus in Vendée (France). This Trematode was identified as Paramphistomum cervi. The snail natural host is unknown. The chaetotaxy of the cercaria differs from that of other European species of Paramphistomum and particularly from P. leydeni and P. daubneyi both species which occur in Vendée. The morphology of the adult precludes any relationship with P. ichikawai also present in Vendée. Therefore it very likely represents a species which was synonymised with P. cervi or a new species.

[Morphology of the teguments of Schistosoma haematobium; comparison with S. curassoni, S. bovis and S. intercalatum]. / Morphologie des téguments de Schistosoma haematobium; comparison avec S. curassoni, S. bovis et S. intercalatum.

Study by SEM of the anterior dorsal teguments of male Schistosoma haematobium from infected rodents. Only paired males, at least hundred days post infection, display a typical morphology. Differentiation from other closely related species obtained experimentally from rodents is possible: bovis: no spines on the tubercles; haematobium: tubercles 10 to 15 microns wide with closely packed spines; curassoni: tubercles over 15 microns wide, with large, closely packed spines; intercalatum: tubercles under 10 microns wide, with scattered spines. It is suggested that the three haematobium genotypes A, B and D are slightly different: A: pointed spines, numerous small additional spines between the tubercles; B: pointed spines, no small additional spines between the tubercles; D: blunt spines. Moreover, the lengths of the prepatent periods in the molluscs of the three S. haematobium genotypes are possibly different: A 72-86 days, B 38-46 days, D 55-58 days. The differentiation of A, B and D is supported by limited data and conclusions on this particular aspect are presented only as a working hypothesis.

[Current risks in the introduction of schistosomiasis into French Guiana]. / Les risques actuels de l'introduction de la schistosomiase en Guyane francaise.

At the moment, it seems unlikely that there is a possibility for schistosomiasis implantation in French Guiana. The reasons to this are both the number of the immigrants infested by Schistosoma mansoni which is quite low and the disappearance of the intermediate host Biomphalaria glabrata. The disappearance of the species may be a temporary one.

[Survey on Schistosomes of man and livestock in Senegal using specific identification given by chetotaxy of cercaria. I. New arguments for the validation of S. curassoni Brumpt, 1931, parasite of man and domestic Bovidae]. / Enquête sur les schistosomes de l'homme et du bétail au Sénégal, à l'aide des identifictions spécifiques fournies par la chétotaxie des cercaires. I. Nouveaux arguments pour la validation de S. curassoni Brumpt, 1931, parasite de l'homme et des Bovidés domestiques.

Study of Senegal cercariae emitted by naturally infected snails or by snails experimentally infected using eggs from human urine or from sheep liver, and study of the corresponding eggs. The relative position of the dorsal sensillae of cercariae is described by an "AD index" and the ratio length/width of eggs by an "L/l index." At the present time, we have not finished the epidemiological studies, certain experiments are imperfect and the isoenzyme analysis of the corresponding adults is incomplete. Nevertheless information given by the indices AD and L/l agree and lead us to admit the existence of a Schistosome different to mattheei, haematobium and bovis and which, following Brumpt and Gretillat we refer to as Schistosoma curassoni. If one relies on the indices, the study indicates that: a) S. mattheei has not been found in Senegal, b) S. bovis is quite rare, c) S. haematobium apparently exists in pure infections in Casamance and in mixed infections with S. curassoni in man in the north and in the east, d) S. curassoni is apparently the dominant species in domestic ruminants and in man in the north and in the east, e) Bulinus umbilicatus is the principal vector of S. curassoni and S. haematobium.

[Potamopyrgus and Bulinids in Corsica (October 1980) (author's transl)]. / Potamopyrgus et Bulins en Corse (Octobre 1980).

A survaey of Corsican Molluscs, in October 1980, confirms the extension of Potamopyrgus jenkinsi. However two types of biotopes could be distinguished. In the first Potamopyrgus is very abundant and Isidora truncata (= Bulinus truncatus) was not found. In the second type Potamopyrgus are less numerous and coexist with Bulinids. That the colonization by Potamopyrgus is relatively ancient leads us to believe that the second type does not correspond to a preliminary stage of contamination, but rather reflects a stage of equilibrium.

[Superficial argentophilic structures of miracidium and cercaria of Schistosoma intercalatum (author's transl)]. / Les organites argyrophiles superficiels des formes larvaires infestantes de Schistosoma intercalatum.

Though it is presently admitted that Schistosoma intercalatum is a well individualized species, detailed studies of superficial argentophilic structures of the miracidium and chaetotaxy of the cercaria do not allow these larval stages to be distinguished from those of S. bovis. Therefore this emphasizes the close relationship between the two parasites.

[Life cycle of Paramphistomum togolense n. sp. (Trematoda, Paramphistomidae)]. / Cycle biologique de Paramphistomum togolense n. sp. (Trematoda, Paramphistomidae).

Mature worms were obtained from a sheep experimentally infested with metacercariae issued from cercariae emitted by naturally infested snails: Bulinus (Bulinus) forskalli collected near Lomé (Togo). Miracidia were used for infection of these laboratory-reared snails which gave numerous cercariae. Larval stages are studied. Morphological and histological characters of the adult and the very peculiar shape of the sporocyst distinguish this trematode from the other known species of the genus. The superficial argentophilic structures of the miracidium and cercaria are described in detail because, to our point, they constitute the best criteria for the taxonomy of this group.

[Therapeutic trials of a new anti-helminthic in Colombian Amazonia: flubendazole]. / Essai thérapeutique d'un nouvel anti-helminthique en amazonie colombienne: le flubendazole.

After a coprologic survey made at Araracuara, a village in colombian Amazonia showing high prevalences of nematodosis, 83 villages (including 55 children below twelve) were given Flubendazole during three consecutive days. The total dose was 600 mg. for children below 12, and 900 mg. for adults. The product efficiency was 88% for Trichuris, 82% for Hookworm, 77% for Ascaris and 43% for Strongyloïdes. The tolerance was excellent in all cases, in spite of heavy parasital infection. The Flubendazole's effect seems to be particularly interesting by its polyvalency.

[Medical practice in Indians of the Colombian Amazon. Epidemiology of intestinal parasitoses]. / Exercice de la médecine chez les indiens d'amazonie colombienne. Epidémiologie des parasitoses intestinales.

In spite of the presence of a physician, the real pathology of an indian population of Colombie is not very well known. Some of ill people are probably entrusted to the traditional "chaman". The western medicine is symptomatic, curative and not preventive. Intestinal nematodiasis and amoebiasis are the major problem. Prevalences are: ascaris 46%, trichuris 30%, ankylostoma 39%, strongyloides 40%, Entamoeba histolytica 30%. Among this slowly evoluting population parasitism is related with cultural factors.

[Presence of Angiostrongylus cantonensis in the Réunion Island. Isolation of the strain]. / Existence d'Angiostrongylus cantonensis a la Réunion Isolement de la souche

The detection of some cases of eosinophilic meningitis suggest that Angiostrongylus cantonensis is present in Reunion Island. Larvae of this nematode have been isolated after dissection of Achatina fulica and have been used to infest laboratory rats. 30 days later, the dissection of these animals shows the presence of young worms in the brain and in the pulmonary arteries. 45 days later, first-stage larvae are recovered from the feces of animals. Now, the strain is maintained in Biomphalaria glabrata and in the rat.

[Development of the Bandama Valley. Sanitary and social problems]. / L'aménagement de la vallée du Bandama. Problèmes sanitaires et sociaux

As with all water resources development projects in countries with hot climate, the man-made lake of Kossou in Ivory Coast presents social and sanitary problems. Although the resettlement and the economic recuperation of the inhabitants are well on the way, the health hazards and especially that of the generalization of schistosomiasis calls for an urgent solution. Though well planed in advance, the creation of this man-made lake, illustrates the necessity at the very beginning of a project that will distrub all the ecology of a region, to establish the total disadvantages and health hazards incurved by the people who live there. To the cost of a project should be added that of measures that would contribute to the reduction of these risks before it is too late.

[Prevention of reintroduction of malaria in Reunion in 1972-1973]. / Prévention contre la réintroduction du paludisme à la réunion en 1972-1973

On the island of the Reunion, malaria was eradicated; however the situation remains precarious because of the presence there of a very effective vector and also because of the frequent trips in neighbouring countries in particular Madagascar. The fight against the reintroduction of this formerly prevalent disease requires strict control of travellers as well as the detection and rapid treatment of imported cases. Ever on a small island with a strong sanitary organization; this vigilance can be difficult.

[Presence of Angiostrongylus cantonensis at la Réunion]. / Présence d'Angiostrongylus cantonensis à la Réunion

The eosinophilic meningitis due to Angiostrongylus cantonensis is well known on Madagascar and on Mauritius Island, but was never described on Reunion Island. Two cases have been lately oberved in Doctor Jay's department at Gabriel Martin's hospital. Local achatines were dissected and contained larvae which, when absorbed by rats, were found in there brains ten days later. These larvae belong certainly to Angiostrongylus genus, but the species has not yet been found with certitude. Lately infested rats are passing through the normal laps of time for adult maturation until they will be sacrified for further examinations.