Congenital chylothorax: from foetal life to adolescence

Aim: To analyse the main prenatal and postnatal features of congenital chylothorax (CC), and the outcome including mid‐term follow‐up. Methods: We searched our databases for CC diagnosed between 1990 and 2006. Data of 29 cases were retrieved and analysed. Follow‐up until 3 years of age was available for all patients. Results: Most patients were diagnosed prenatally (94%) and most cases were complicated by foetal hydrops (66.7%). The overall survival rate at 3 years was 56%. A significantly poorer outcome was observed when foetal hydrops, preterm birth < 34 weeks, large effusions and/or early‐onset pneumothorax were present. An important but not significant improvement in the survival rate was observed through the study period; while in 1990–1998, the survival rate was 41.7%, from 1999 to 2006 it was 66.7% (p = 0.19). In the mid‐term follow‐up, we did not observe any recurrence of CC and most infants remain asymptomatic. However, 27% of survivors were diagnosed as having asthma in early infancy. Conclusion: CC still carries a significant risk of perinatal mortality. However, continuous advances in foetal and neonatal medicine are improving the prognosis of these patients, and nowadays most of them are likely to survive. Beyond the neonatal period, most survivors have an uneventful outcome.     

Exploiting the potential of vector control for disease prevention

Although vector control has proven highly effective in preventing disease transmission, it is not being used to its full potential, thereby depriving disadvantaged populations of the benefits of well tried and tested methods. Following the discovery of synthetic residual insecticides in the 1940s, large-scale programmes succeeded in bringing many of the important vector-borne diseases under control. By the late 1960s, most vector-borne diseases--with the exception of malaria in Africa--were no longer considered to be of primary public health importance. The result was that control programmes lapsed, resources dwindled, and specialists in vector control disappeared from public health units. Within two decades, many important vector-borne diseases had re-emerged or spread to new areas. The time has come to restore vector control to its key role in the prevention of disease transmission, albeit with an increased emphasis on multiple measures, whether pesticide-based or involving environmental modification, and with a strengthened managerial and operational capacity. Integrated vector management provides a sound conceptual framework for deployment of cost-effective and sustainable methods of vector control. This approach allows for full consideration of the complex determinants of disease transmission, including local disease ecology, the role of human activity in increasing risks of disease transmission, and the socioeconomic conditions of affected communities.     

Comparative performances,under laboratory conditions,of seven pyrethroid insecticides used for impregnation of mosquito nets

OBJECTIVE: To compare the efficacy of seven pyrethroid insecticides for impregnation of mosquito nets, six currently recommended by WHO and one candidate (bifenthrin), under laboratory conditions. METHODS: Tests were conducted using pyrethroid-susceptible and pyrethroid-resistant strains of Anopheles gambiae and Culex quinquefasciatus. Knock-down effect, irritancy and mortality were measured using standard WHO cone tests. Mortality and blood-feeding inhibition were also measured using a baited tunnel device. FINDINGS: For susceptible A. gambiae, alpha-cypermethrin had the fastest knock-down effect. For resistant A. gambiae, the knock- down effect was slightly slower with alpha-cypermethrin and much reduced following exposure to the other insecticides, particularly bifenthrin and permethrin. For susceptible C. quinquefasciatus, the knock-down effect was significantly slower than in A. gambiae, particularly with bifenthrin, and no knock-down effect was observed with any of the pyrethroids against the resistant strain. Bifenthrin was significantly less irritant than the other pyrethroids to susceptible and resistant A. gambiae but there was no clear ranking of pyrethroid irritancy against C. quinquefasciatus. In tunnels, all insecticides were less toxic against C. quinquefasciatus than against A. gambiae for susceptible strains. For resistant strains, mortality was significant with all the pyrethroids with A. gambiae but not with C. quinquefasciatus. Inhibition of blood-feeding was also high for susceptible strains of both species and for resistant A. gambiae but lower for resistant C. quinquefasciatus; bifenthrin had the greatest impact. CONCLUSIONS: Efficacy for impregnation of mosquito nets against A. gambiae was greatest with alpha-cypermethrin. Bifenthrin is likely to have a significant comparative advantage over other pyrethroids in areas with pyrethroid resistance because of its much stronger impact on the nuisance mosquito, C. quinquefasciatus, despite its slower knock-down effect and irritancy. Selection of pyrethroids for mosquito vector control and personal protection should take into account the different effects of these insecticides, the status of pyrethroid resistance in the target area, and the importance of nuisance mosquitoes, such as C. quinquefasciatus.     

Cyfluthrin (EW 050)-impregnated bednets in a malaria control program in Ghassreghand (Baluchistan, Iran)

In a study carried out in the Ghassreghand Division (Baluchistan, Iran) from March through November 1995, efficacy of cyfluthrin-impregnated bednets was compared to that of untreated nets, in relation to malaria control. Ten villages with a total population of 4,572 and 3 villages with a total population of 1,935 were used as treatment and control, respectively. The collection, impregnation (target dosage of 40 mg active ingredient [AI]/m2), and redistribution of the nets (9% nylon, 52% light cotton, 30% medium cotton, and 9% heavy cotton), carried out in mid-April, were done by local health workers, supervised by the senior research staff. Anopheles culicifacies was considered to be the main vector of malaria in the named area. This species is mainly zoophilic, endophilic, and exophagic. The initial uptake of the insecticide was lower than the target dosage, with high variation (nylon, 12.5 +/- 5.4 mg AI/m2; light cotton, 33.3 +/- 26.1 mg AI/m2; medium cotton, 25.9 +/- 20 mg AI/m2; heavy cotton, 17.6 +/- 12.5 mg AI/m2). The use of impregnated mosquito nets (used primarily outside) had no significant effect on the incidence of malaria. No difference was detected in the parasite density of patients with positive slides. No significant effect was observed in the parous rate, human blood index, and sporozoite rate of anopheline vectors. Only the indoor resting densities of An. culicifacies and other malaria vectors were drastically reduced after the introduction of the cyfluthrin-impregnated nets into the treatment villages. The residual activity of cyfluthrin was lower than expected. The mortality of anophelines brought in contact with the treated nets for 3 min in bioassays dropped to less than 55% in 3 months. The loss of chemical activity was greatest for the light cotton nets, followed by the medium cotton nets. Cyfluthrin-treated nets were mildly irritating to host-seeking female anophelines in the laboratory. The protective rate of impregnation (all fabric kinds included) in preventing female mosquitoes from biting through the impregnated nets was initially 5-6 times that of the nonimpregnated nets. The study did not detect any significant difference between the use of untreated versus impregnated bednets in the Ghassreghand area. In planning future medium-scale trials, comparison of new compounds and formulations to the more widely used pyrethroids such as permethrin and deltamethrin is highly recommended.     

Cross‐sector emergency planning for water supply utilities and healthcare facilities

The purpose of this article is to outline the criticality of water supply in sustained operations of healthcare facilities, particularly during community emergencies, and to advocate for enhanced cross‐sector support from the water utilities in meeting this need. Information and ideas presented here were developed in the course of a regional project sponsored by the Metropolitan Washington Council of Governments (MWCOG) for development of emergency water supply operations plans for critical water uses in the Washington, DC, area.     

Sexual behavior,communication, and chlamydial infections among college women

The sexual practices, partner communication patterns, and prevalence of chlamydial infection were determined in a sample of college women. Specific inclusion criteria were used to screen 146 participants. The presence of a mucopurulent cervical discharge was the only criterion significantly associated with infection. Only 12% of the sample used condoms alone or in combination with another birth control method, and only 31% of the women discussed with their partner their own or their partner's sexual history. Thirty‐eight percent of the sample reported a history of one to four episodes of a sexually transmitted disease, and 21% of the women stated they had had two or more sexual partners within the past 6 months. Health providers, counselors, and women themselves must address this health issue with more assertive behavior and communication skills.     

Effectiveness and residual activity comparison of granular formulations of insect growth regulators pyriproxyfen and s-methoprene against Florida mosquitoes in laboratory and outdoor conditions

Effectiveness and residual activity tests of granular formulations of 2 insect growth regulators (IGRs), s-methoprene and pyriproxyfen, against laboratory-reared larvae of 5 colonized mosquitoes, Aedes aegypti, Aedes albopictus, Aedes taeniorhynchus, Anopheles quadrimaculatus, and Culex nigripalpus, were conducted in the laboratory and outdoors in plastic tubs. Culex quinquefasciatus was exposed to these two IGRs in the laboratory only. Each IGR formulation was applied at 0.02 and 0.05 ppm active ingredient (Al) against 5 of the 6 mosquito species both in the laboratory and the outdoor evaluations, whereas Cx. quinquefasciatus was exposed to 0.2 and 0.4 ppm AI of s-methoprene, and 0.1 and 0.2 ppm AI of pyriproxyfen in the laboratory. s-Methoprene at 0.02 and 0.05 ppm AI resulted in variable levels (<39-100%) of inhibition of adult emergence in the 5 species monitored for 6 weeks after treatment under both test conditions. Aedes taeniorhynchus was the most susceptible to s-methoprene in terms of initial and residual activity. Culex quinquefasciatus and Ae. albopictus were the most tolerant to s-methopene, with maximum emergence inhibitions amounting to 84% in Cx. quinquefasciatus at 0.4 ppm and 44.3% in Ae. albopictus at 0.05 ppm during the 1st week in the laboratory. Pyriproxyfen at comparable treatment rates to s-methoprene caused very high levels (>80-100% in most cases) of initial and residual emergence inhibitions of the tested species in the laboratory as well as outdoors. In several species, pyriproxyfen induced complete inhibition of adult emergence for several weeks after treatment, even at the lower rate of 0.02 ppm. The World Health Organization has recently recommended the use of pyriproxyfen for the control of some mosquito species at specified rates in certain habitats.     

Malaria control in Iran--present and future

The malaria eradication campaign in Iran, which started in 1958, has not been able to achieve its final goals. The technical, administrative, socio-economic and financial obstacles involved in this unfinished task are mentioned and the present status of malaria in the country is discussed. It is urged that eradication policy, presently used, be substituted by malaria control program, as defined by The World Health Organization. This would serve as a prerequisite for eventual eradication of malaria, from the country, in the future. Within such agreement, the improvement of basic health services and search for better technical means of controlling the transmission of the infection are emphasized as vital to achieve this goal. Intensive training of experienced staff, in Iran, for stimulation and promotion of relevant research and training activities in malaria control is highly recommended.     

Confirmation of high blood flow rates through 150 μ filter/high-flow tubing

Many new products designed to assist in rapid blood infusion are appearing. Some highly touted and routinely used devices for intravenous (IV) infusion have recently been shown to be, at least in part, defective. A tubing with an in-line 150 μ filter (150 μ High-Flow Blood Filter; Saftifllter^® Blood Administration Sets; Cutter Biological, Berkeley, CA 94710) has recently been introduced to facilitate rapid blood transfusion. It is claimed that at least 8.5 units of blood can be rapidly run through each set before replacement is necessary. To test this under simulated clinical conditions, four sets of ten random units of outdated erythrocytes at 4 to 9°C were each admixed with 250 mL 70°C 0.9 NaCl and infused through the system under a constant 300 mmHg pressure. Two sets infused through unmodified tubing flowed at an average of 25 mL/sec (1500 mL/min) before there was an appreciable slowing of the flow rate. Two sets with 8 Fr catheters attached infused at an average of 22 mL/sec (1320 mL/min) before there was an appreciable slowing of the flow rate. Even after the flow slowed, the 9th and 10th units infused at an average greater than 10 mL/sec (600 ml/min). The tubing/filter exceeded the manufacturer's published claims. This tubing/filter appears to be one element that could be an effective component of a high-flow infusion system.     

Transient synovitis of the hip in children: role of US

Transient synovitis of the hip remains a common diagnostic problem for the clinician. The physical signs are not pathognomonic of the condition, and the classic technical examinations are of little help. Therefore, the authors retrospectively studied the value of hip arthrosonography in 46 children with clinical symptoms suggesting pathologic hip conditions. In 20 of the 21 patients with a final diagnosis of transient synovitis, articular effusion was detected on ultrasound (US). Conventional radiography showed an increased medial joint space in only eight of these patients. Increased echogenicity of the articular fluid was found in both transient synovitis and septic arthritis. The high sensitivity of US in detecting intraarticular fluid was demonstrated by cadaver studies.