Field efficacy of expanded polystyrene and shredded waste polystyrene beads for mosquito control in artificial pools and field trials, Islamic Republic of Iran.

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes (86% and 78% reduction respectively 2 weeks after treatment). There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries.

Field efficacy of expanded polystyrene and shredded waste polystyrene beads for mosquito control in artificial pools and field trials, Islamic Republic of Iran

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes [86% and 78% reduction respectively 2 weeks after treatment]. There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries

Survey of microbial quality of drinking water in rural areas of Kashan-Iran in second half of 2008.

The objective of the study is surveying microbial quality of drinking water in Kashan rural areas and determining the rural population that using safe water in terms of microbial quality in second-half of 2008. In this cross-sectional study, microbial quality of water in all rural areas was determined in 3 stages based on 3 parameters as Total Coliforms, Fecal Coliforms and Heterotrophic Plate Count (HPC). The results of this study illustrates that 100.0, 47.71 and 92.99% population in under coverage and non under coverage areas of Kashan Rural Water and Wastewater Company (KRWWC) and all Kashan rural areas, respectively using safe water in terms of Fecal Coliforms and 98.4, 21.2 and 88.00% population in under coverage and non under coverage areas of KRWWC rural areas and all Kashan rural areas, respectively using safe water in terms of Total Coliforms. There is also a meaningful difference in microbial quality between under coverage and non-under coverage rural areas. The results of this study express that the fecal contamination in under coverage rural areas is excellent, but there is a bad condition in non-under coverage areas. Generally, the microbial quality in all Kashan rural areas is approximately equal to national microbial criteria. Its been also illustrated that the role of KRWWC in supplying safe drinking water in terms of microbial quality for rural population is very important.

Using irradiation treatment for reduction of anaerobic bacteria from a wastewater treatment plant.

This study was done to investigate the reduction of anaerobic bacteria (Clostridium perfringens) by ultrasound irradiation technology (USI). C. perfringens is the most important of the sulfite-reducing clostridia and is normally present in human and animal feces. Clostridial spores survive longer than coliforms, Escherichia coli or enterococci, and are consequently used as an indicator of past fecal pollution. The spores are not always inactivated by chlorination, but are not a hazard to health in potable water. C. perfringens are very resistant to chlorine and other drinking-water disinfectants. Conventional water treatment practices including chlorination are sometimes inadequate for inactivation of C. perfringens. Ultrasound irradiation is able to inactive C. perfringens through a number of physical and chemical effects arising from acoustic cavitation. The phenomenon of cavitation, which involves formation, growth, and violent collapse of vapour bubbles in a liquid media, is known to generate a high-intensity pressure, which affects the cell and C. perfringens' viability. Cavitations disrupt C. perfringens. Ultrasound irradiation at a frequency of 42 kHz was used to expose aqueous suspension of C. perfringens to evaluate the disinfection efficacy of ultrasound irradiation. Results indicated a significant increase in reduction of C. perfringens with increasing ultrasound time. C. perfringens was inactivated by 99.98% after 90 min.

Study of natural organic matter fractions in water sources of Tehran.

Natural Organic Matters (NOMs) are abundant in natural water resources and in many ways may affect the unit operations in water treatment. Although, NOMs are considered harmless but they have been recognized disinfection by-products precursors (DBP(s)) during the chlorination process. Formation of DBP(s) highly depends on the composition and concentration of NOM, which can be broadly divided into two fractions of hydrophobic (humic) and hydrophilic (non-humic) substances. The objective of this study was to determine Natural organic matter and its fractions concentration in the surface water sources of Tehran. Water sampling was conducted monthly between May to July 2006 in three rivers Lar, Jajrood and Karaj as the main drinking water supplying sources in Tehran. Quantitative parameters of pH, EC, UV254 and DOC were studied based on to standard methods. The XAD-7 resin method was used for fractionation of NOM. Results showed that NOM concentrations in Lar, Jajrood and Karaj rivers were 8.53, 12.9 and 11.3 mg L(-1), respectively. The HPO (hydrophobic) fraction was predominant compared to the HPI (hydrophilic) fraction in the all of water samples. The mean of total percent of HPO and HPI fractions were about 57 and 43%, respectively. Since the hydrophobic NOM fraction exhibits higher trihalomethane formation potential (THMFP) than hydrophilic NOM, Tehran water chlorination exhibits higher THMFP than haloacetic acid formation potential (HAAFP). The information obtained from this study may be further employed in the design of the control technique and management strategies for the water treatment plant, especially for DBP(s) reduction.

Development of the Regional Malaria Training Centre in Bandar-e Abbas, Islamic Republic of Iran.

The resurgence of malaria has highlighted the need for training health professionals in malaria control planning. The course described here was organized jointly by the World Health Organization, the Ministry of Health and Medical Education and the School of Public Health in Iran. The first course was held in 1997 and the fifth WHO-approved course is now in progress. The course focuses on dynamic, interactive, practical and problem-solving learning methods. It provides the participants with the knowledge, skills, competence and confidence to be able to analyse the malaria problem. The course fulfils the requirements of the Roll Back Malaria campaign. In the 8-week training period subjects such as basic bio-statistics and epidemiology, microcomputing, malaria parasitology, malaria entomology, vector control, case management, epidemiological approach to malaria control, field work and planning for malaria control are taught. Each participant is evaluated in each subject. A total of 71 participants from 17 countries in the WHO African and Eastern Mediterranean Regions, mainly those with a malaria problem, have graduated.