Annales de parasitologie humaine et comparee最新文献

The problem of the human Simuliidosis (caused by black flies) is reviewed for the France: important and, perhaps, relatively recent increase from the known human attacks by black flies. Countries and anthropophilic species are cited.

A study of 94 slugs, collected from urban and rural areas in and around Léon, Nicaragua, was carried out in order to confirm the role of Vaginulus plebeius as an intermediate host of Angiostronglylus costaricensis. Third-stage larvae of A. costaricensis were obtained from these molluscs. Some of these larvae were then orally inoculated into two laboratory-bred rats Sigmodon hispidus and adult worms of A. costaricensis were recovered two months later. The infection rate of these slugs ranged from 4% in urban areas to 85% in rural areas. These data suggest that contamination to man is a major risk especially in rural areas and that abdominal angiostrongyliasis could be a health problem in Nicaragua.

Paralibyostrongylus hebrenicutus accomplishes its life cycle spontaneously in captive Atherurus africanus, its natural host, and in experimentally infected guinea pigs and rabbits. Morphogenesis and larval morphology were studied in the guinea pig and described herein. Host infection were achieved either by subcutaneous or by oral inoculation. The entsheathed infective larvae moult soon after penetration in the vertebrate host. Following subcutaneous inoculation, they reach the lungs very probably through the lymphatic vessels and the right heart at H8, and the stomach as soon as D2. However, a possible direct migration by the mesenteric lymphatic vessels and crossing of the digestive wall cannot be excluded as a few larvae were found in the peristomachal mesentery. Following ingestion, L3 larvae reached the stomach directly. 24 hours post-ingestion, they were localized deep inside the gastric mucosa crypts lumen. The same larval localization was observed at D3 after a subcutaneous inoculation. At D5, regardless of the inoculation route, larvae reached their definitive position, embedded in the gastric mucosa mucus lining, where they underwent the 3rd moulting (L3-L4) followed by the 4th moulting (L4-Ad) at D19. Eggs appeared at D28. Except for the inflammatory granuloma seen in the lungs and the mesentery from H24 to D3, the nematode induced no tissue lesion. The genus Paralibyostrongylus is one of the most primitive in the Libyostrongylinae-Cooperiinae line. The double transmission route, may have made possible the transition from primitive cycles by cutaneous penetration to more specialized cycles by the oral route, the latter being responsible for the evolutionary success of the group in large herbivores.

The causative agent of cutaneous leishmaniasis in Mauritania is identified for the first time as Leishmania major MON-117, a new zymodeme closely related to MON-26. The authors point out the need to study this previously unknown focus.

When inoculated subcutaneously, the infective larvae of L. sigmodontis undergo complete development and produce a patent microfilaraemia in mice of the BALB background (BALB/c, BALB/K and BALB/B, with respectively the H-2d, H-2k et H-2b haplotypes). The most susceptible strain is BALB/c with all mice harbouring adult filariae and 47% of mice presenting with a patent microfilaraemia. Mice with the B10 background (B10, B10Br and B10D2, with respectively the H-2b, H-2k et H-2d haplotypes) are almost completely resistant to infection. Adult filariae were recovered from all mice of the CBA/Ca, CBA/HN, C3H/HeN, DBA/2N strains. However, the site and structural development of the parasite varied in each strain. Absence of microfilaraemia is associated with absent or abnormal spicules, reduced number of female filariae and small size of female filariae. These results show that the Major Histocompatibility Complex only modulates the developmental pattern of filariae within the limits imposed by background genes. Male CBA/HN and C3H/HeN were more susceptible to infection than female mice. Inverse phenomenon was observed with strains BALB/c; and, no host sex effect was seen in DBA/D2N.