What parents in Australia know and do about head lice.

INTRODUCTION: Although parents in developed market economies regard head lice infections (pediculosis) as a significant problem, health departments generally rate pediculosis as a low priority health issue, encouraging parents to manage and control it. But how well equipped and willing are parents to manage the infections? There do not appear to be any studies in the literature addressing these issues. This article presents the results of a survey conducted in Australia that aimed to answer these questions. METHODS: A cross-sectional survey of parents of primary school aged children in Victoria (Vic) and north Queensland (NQ) was conducted using a self-administered questionnaire. The study investigated the knowledge, attitudes and practices of parents regarding head lice infections. RESULTS: Only 7.1% of 1338 who completed the questionnaire answered all 10 knowledge questions correctly and more than one-third failed to answer half correctly. There was a weak negative correlation between parents' knowledge and the prevalence of active pediculosis in the school. Almost all parents wanted the responsibility for treating pediculosis and more than three-quarters saw it as a health concern. A higher proportion of parents in NQ used preventative strategies (67% vs 41%). Most parents spent less than AU$50 per year on treatments. Alarmingly, however, the proportion of children missing school as a result of pediculosis was 24.4% and 30.3% in Vic and NQ, respectively. In Vic there was a positive correlation (r = 0.39) between missing school in the previous 12 months and prevalence of pediculosis in the school. CONCLUSIONS: This appears to be the most comprehensive study of parental knowledge, beliefs, and practices regarding head lice infections. Although parents wanted responsibility for the management of pediculosis, deficiencies in their knowledge indicate they may be inadequately equipped to do so. Given the high proportion of children in both states who have missed school as a result of head lice, it is recommended that health departments in Australia should work to ensure that consistent and accurate messages about pediculosis are disseminated, and that relevant legislation is amended to prevent children being excluded from school.

In vitro effects of low concentrations of penicillin and sulfadiazine on Streptococcus mutans.

Investigations were conducted to determine the in vitro effects of low levels of penicillin and sulfadiazine on the growth, plaque formation, and agglutination of Streptococcus mutans and on the synthesis and activity of enzymes synthesizing extracellular polymers. The concentrations tested were equivalent to those expected in the saliva of subjects receiving oral therapy with the agents. Penicillin at 0.5 ng/ml and sulfadiazine at 1 mug/ml substantially inhibited in vitro plaque formation. At these concentrations, sulfadiazine but not penicillin also inhibited growth of the organism. Neither antimicrobial agent affected the agglutination of S. mutans with dextran or the synthesis or activity of enzymes synthesizing extracellular polymers. The effect of sulfadiazine on plaque formation was attributed, at least in part, to the inhibitory action of that agent on S. mutans growth.

Effect of long-term therapies with penicillin and sulfadiazine on Streptococcus mutans and lactobaccilli in dental plaque.

Plaque samples were obtained from 13 children receiving long-term therapy with benzathine penicillin for the prevention of rheumatic fever recurrences, 31 children receiving oral sulfadiazine for the same purpose, and 29 untreated siblings. The therapies were found to have no effect upon the proportions of Streptococcus mutans or lactobacilli in dental plaque, upon the percentage of children harboring the organisms, nor upon the susceptibility of the organisms to penicillin and sulfadiazine. Of the S. mutans strains tested, 97% had a minimal inhibitory concentration of penicillin G of less than 48 ng/ml and, of the lactobacillus strains tested, 96.8% had a minimal inhibitory concentration of less than 1,600 ng/ml. All strains of both organisms were profoundly resistant to sulfadiazine.