Louse comb versus direct visual examination for the diagnosis of head louse infestations.

The techniques used for diagnosis of head louse (Pediculosis capitis) infestation are a source of controversy. Most epidemiologic and diagnostic studies have been done using direct visual examination. The main objective of this study is to compare the efficacy of direct visual examination versus the louse comb method. The hair of each child was examined twice; one team used a screening stick and another team used a louse comb. Seventy-nine boys and 201 girls, 7-10 years old were examined. Examination with a louse comb found that 25.4% of the children were infested with both lice and nits, while another 31.3% had nits only. Boys were significantly less infested with lice and nits than girls (lice: 15.2 and 29.6%; nits: 21.5 and 35.4%, respectively). The infestation rate with lice and nits was significantly higher in children with long (68.9%) and medium-length (63.9%) hair than in children with short hair (44.0%) (p < 0.01). Direct visual examination found that 5.7% of the children were infested with both lice and nits, and another 49.0% with nits only. The average time until detection of the first louse was 57.0 seconds with the comb as compared to 116.4 seconds by direct visual examination. Diagnosis of louse infestation using a louse comb is four times more efficient than direct visual examination and twice as fast. The direct visual examination technique underestimates active infestation and detects past, nonactive infestations.

Permethrin resistance in the head louse Pediculus capitis from Israel.

Head lice, Pediculus capitis, were collected from children aged 3-12 years in Maale Adumin, a town near Jerusalem, after reports of control failure with the pyrethroid insecticide permethrin. A total of 1516 children were examined: living lice and eggs were found on 12.1% of the children; or another 22.8% of the children only nits were found. Twice as many girls as boys (8.1% v 4%) were infested with lice and or nits. Head lice collected from infested children were exposed to permethrin impregnated filter-papers. Log time probit mortality (ltp) regression lines were calculated for mortality data and compared to ltp lines for a similar collection of head lice made in 1989. The regression lines for the two years were significantly different, with a 4-fold decrease in susceptibility at the LT50 level between 1989 and 1994. The slopes of the lines also suggested that the 1994 population was more heterogenous in its response to permethrin than the 1989 population. In contrast, a laboratory population of body lice (Pediculus humanus) tested with the same batch of permethrin-impregnated papers showed a slight but non-significant increase in susceptibility between 1989 and 1994. The results suggest that resistance to pyrethroids has developed rapidly among head lice since permethrin was introduced in 1991 as a pediculicide in Israel.

[Intervention program for prevention of premature deliveries in Beit Shemesh].

Programs for the prevention of premature births have been developed world-wide to reduce perinatal mortality and child morbidity and handicaps. The Beit Shemesh intervention program focused on locating and improving socio-economic conditions, in addition to medical-nursing aspects. Beit Shemesh (located 30 km SW of the nearest Jerusalem hospital; population 14,000; 350-400 births per year) was chosen because its rates for preterm delivery (36 weeks or less) and for low birthweight neonates were higher than the national rates, it was of low socio-economic status, and because of its well-developed and accessible local health services infrastructure. The main goals of the intervention program were to reduce significantly the rates of preterm deliveries and that of low birthweight neonates to at least the national rates. Pregnant women who received treatment at family health centers were interviewed and classified according to a preterm birth-risk screening scale. The scale was constructed for this project to measure the degree of risk according to medical, nursing and socioeconomic criteria. Women identified as at-risk were invited for more intensive medical, nursing and social follow-up, according to their individual needs. The intervention of a social worker was a special part of the project. The findings, after 4 years of project intervention, showed a significant decrease in the rate of preterm births: 8.6% in the control group before the program was implemented as compared to 5.4% in the case group (p less than 0.01). There was a decrease in the percentage of low birthweight neonates to 7.9% near the average rate for the Jewish population in Israel.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidemiological studies on head lice infestation in Israel. I. Parasitological examination of children.

Of 3,079 children in a medium-sized community near Jerusalem, 11.2% were found to be infested with living lice and eggs and another 23.4% had only nits. Boys and girls were equally infested. The incidence of infestation was highest among children 4-11 years of age. About 78% of the infested children had from one to ten lice. Approximately 80% of the infested children had nits that were 2-5 cm away from the scalp. Boys with medium length hair and girls with short hair showed the highest incidence of lice infestation. Children with brown and red hair were more infested than those with black and blond hair. Boys and girls with straight and wavy hair were more infested than those with curly and frizzy hair.

Head lice in Israeli children: parents' answers to an epidemiological questionnaire.

BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members.