Studies on Human Head Louse Pediculus humanus capitis (Anoplura) Infestation (Case Report)

Thirteen cases of the human head louse infestation (Pediculus humanus capitis De Geer, 1778) in Okayama City were reported. All the patients were found in ages between 2 and 35, and the highest incidence ranged in the age group of 10 years old and younger. The sex ratio of the patients was higher in female than in male. The patients were recognized more often in the early winter months of November and December. Adults and/or eggs (nits) of Pediculus louse were localized on hair of all the patients. For the patients Eurax (Crotamiton) cream containing 3% benzyl benzoate was used and the results were remarkable

Studies on House-Dust Mites. The Itching Dermatitis in Okayama Prefecture, Japan

Seventy-three patients (52 females and 21 males) with suspected itching dermatitis caused by house-dust mites admitted to our hospital during the period of June 1984 to December 1991. Survey of the mites in house-dust collected from the residences of all patients was carried out to clarify the precise relationship between itching dermatitis and causative mites. The patients were more in female (71.2%) than in male (28.8%), and the highest incidence was observed in female in forties (19.2%). The mite infestation occurred most in August and September in every year. Eighteen mite species in 11 families were found in 56 (76.7%) out of 73 cases. The dominant species were Dermatophagoides farinae (47.9%), D. pteronyssinus (27.4%), Haplochthonius simplex (26.0%), Chelacaropsis moorei (24.7%), Cosmochthonius reticulatus (21.9%), Laelaps spp. (11.0%), Dermanyssidae spp. (7.7%), Cheyletus fortis, Tyrophagus putrescentiae and Hirstia domicola (6.8% each). In 32 (43.8%) out of 73 cases, 5 mite families such as Cheyletidae (34.2%), Laelapidae (11.0%), Dermanyssidae (7.7%), Macronyssidae (Ornithonyssus bacoti) (2.7%) and Pyemotidae (1.4%) were confirmed. Therefore, it reveals that the itching dermatitis found in 32 patients were caused by the mites inhabiting in house-dust

Studies on the Head Structure of Spirometra erinacei (Cestoda, Pseudophyllidea) Plerocercoid by New Stretching-Fixation Method

Development of new fixation method for maintaining the head region of Spirometra erinacei kept stretched in aqueous chemicals was worked out, and the external morphology of the well-stretched head of plerocercoid was studied under light and scanning electron microscopy. The stretching method for plerocercoid head was most effective when specimen was placed in 10% ethanol Ringer solution for 5 minutes after soaking several hours in 0.1% chloretone Ringer solution. In the plerocercoid head, the bothria and bothridia were clearly found on the dorsal and ventral surfaces, and a frontal pit was also found on the apical end in the same manner as that of some diphyllobothriid cestodes, Diphyllobothrium ditremum, D. dendriticum and D. vogeli. Morphological appearance of microtriches on the surface of frontal pit periphery were quite different from those of other parts of the head surface

A Case Report on the Human Infestation by a Hard Tick Ixodes nipponensis Found in Okayama, Japan (Acarina : Ixodidae)

A case of hard tick infestation to a patient, 75-year-old male living in Wake-Cho, Okayama Prefecture is reported. The patient seemed infested by ticks at his backyard bamboo bush where he had entered every other day for trash dumping. The tick was found on the skin surface of left axilla region in early June, 1984. On acarological observations the tick was identified as an adult female of Ixodes nipponensis Kitaoka and Saito, 1967 based on its body size and the morphological features of scutum, coxae and spiracular plates. This report is the second case of human infestation with hard ticks in Okayama Prefecture,Japan

Child Infestation with the Hard Tick Haemophysalis flava (Acarina : Ixodidae) Found in Okayama, Japan (Case Report and Bibliographical Review)

A case and bibliographical review of child infestation with the hard ticks are reported. On December 4th, 1984, the tick bite was found on the skin surface of temporal region behind the right ear of a 2-year-old boy living in Okayama, Japan. The collected tick body (ideosoma) measured about 5.0 mm in length and 4.0 mm in maximum width not counting capitulum. By the acarological observation, the tick was identified as an adult female of Haemophysalis flava Neumann, 1897 based on morphology of scutum, coxae, internal spurs and spiracular plates. In this case, the tick infestation occurred when the boy was playing on the grass, and it seems to be a unique case because the victim was quite young and the incidence happened in less common winter season. To our best knowledge, this report is the third human case infested with hard tick in Okayama Prefecture, Japan. Details with bibliographical data are reported