[Comparison of PBO and DEF effects on creating bendiocarb and carbaryl insecticide resistance in German cockroach]

German cockroach [Blattella germanica, Blattodea:Blattellidae] is considered one of the common pests in hospitals, hotels, households and dormitories which can transfer different pathogenic fungi, viruses and bacteria. The aim of this study was to determine the resistance mechanisms to bendiocarb and carbaryl in German cockroache, in vivo. In this study, German cockroach strains were collected from several hospitals and dormitories in Tehran and transferred to insectarium. The strains were reared under the same laboratory conditions. At first the discriminative doses of bendiocarb and carbaryl were determined by surface contact method. Then the susceptibility level and types of resistance mechanisms to bendiocarb and carbaryl, in the strains were studied by using PBO and DEF as synergists. Simultaneous use of DEF as synergist, with bendiocarb and carbaryl led to the breakdown of resistance in all strains. But use of PBO instead of DEF did not overcome the resistance in the strains collected from Mofid, Alvand and Vali Asr hospitals and Shariati dormitory. In general, the effect of DEF in breaking the resistance was more than that of PBO. Complete breakdown of resistance after simultaneous use of DEF with bendiocarb and carbaryl insecticides, indicated the essential role of esterase enzymes in producing resistance to bendiocarb and carbaryl in the strains. But PBO did not break the resistance completely in most wild strains, which may be due to other possible mechanisms of resistance such as reduction of cuticle penetration or insensitivity to acetyl cholinesterase enzyme

[Survey of optimal methods for the control of cockroaches in sewers of Qom city]

Domestic sewers and wastewater treatment plants are suitable places for the growth of some types of Cockroaches. Annually the water and wastewater company of Qom city make considerable attempts to overwhelm the problem. The current study is aimed to determine types of Cockroaches and select the optimal methods for their control. In this study, 120 manholes are selected in different locations of Qom city, the numbers of Cockroaches are counted and the Cockroaches are classified into different groups. Then, each group are faced to different insecticides Including Simperator, Diazinon, Dursban Ec, Faikam, Sipermetrin, Icon, Deltametrina and Sulfac. One group of manholes was considered as blank sample during one month. Counting and determination of Cockroaches in these manholes conducted before using insecticides and also five months after it. the study showed that all sewers were 100% polluted by Cockroaches. The number of Cockroaches in manholes range from minimum 4 to maximum 3600 in each manhole. The applied of insecticides including Dursban Ec, Simperator, Sulfac, Dursban, and Deltametrina are used 2 gr in 100 square meter of area of each sewer. The Cockroaches population reduced to approximately zero after application of these insecticides. Spraying sewers by Simperator controlled 100% of Cockroaches. the most effective method for the control of Cockroaches was usage of 2 gr of Dursban [Ec] in squaremeter of area in the beginning of warmseason.If we use 1-1/5months interval between the time of spraying insecticide in selected wells, with using simperator and dursban [Ec] we can overwhelm Cockroaches using Simperator and Dursban Ec. The results of statistical analysis show that reduction of number of coackroaches in one month after using poison is significant [P-value<0.05]. But after 5months it lose meaningful in all of them.Also, reduction of number of coackroaches in blank manholes was not statistically significant

Epidemiology of head lice infestation in primary school pupils, in Khajeh city, east Azerbaijan Province, Iran

Pediculus capitis [Anoplura: Pediculidae] or head louse is an obligate ectoparasite transmitted mainly through physical contact. This study was conducted to survey the prevalence of head lice infestation rate and some risk factors in Primary School pupils, in Khajeh City East Azerbaijan Province, Iran We selected 20 primary schools of Khajeh City during 2008 and 2009. Totally 500 pupils including 200 boys and 300 girls from all grade 1-5 were selected by multistage, systematic random sampling in rural areas of Khajeh City and were examined for lice. In addition, a standard questionnaire recorded information about demographic features of each pupil. Results were analyzed by SPSS software. The total prevalence of head lice infestation in this study was 4.8%. and the prevalence rate was significantly higher in girls [6.66%] than in boys [2%]. Epidemiological factors such as: sex, school grade, family size, parent's education, type of house, hair washing [per week], number of using comb per day, were evaluated and results showed significant difference in head lice infestation and sex, school grade, family size, father education, and type of house [P<0.05]. Pediculosis is a public health problem in many parts of the world, and due to the higher prevalence of pediculosis in crowded families, family by lower levels of father's education and socioeconomic status in our study and rural area, it is necessary to give health education for families to prevent of pediculosis in this area