Urban Health Bulletin – June 2010
Below are citations and abstracts to 13 urban health studies published in June 2010.
1 – Arch Dis Child. 2010 Jun 22.
Reported care giver strategies for improving drinking water for young children.
McLennan JD, Farrelly A. University of Calgary, Calgary, Canada.
Objectives – Care givers may engage in a variety of strategies to try and improve drinking water for children. However, the pattern of these efforts is not well known, particularly for young children in high-risk situations. The objective of this study was to determine care giver-reported strategies for young children with (1) undernutrition and (2) living in an unplanned poor peri-urban community in the Dominican Republic.
Methods – Practices reported by care givers of young children from a community and clinic group were extracted from interviews conducted between 2004 and 2008 (n = 563). These results were compared to two previous similar samples interviewed in 1997 (n = 341).
Results – Bottled water is currently the most prevalent reported strategy for improving drinking water for young children. Its use increased from 6% to 69% in the community samples over the last decade and from 13% to 79% in the clinic samples. Boiling water continues to be a common strategy, particularly for the youngest children, though its overall use has decreased over time. Household-level chlorination is infrequently used and has dropped over time.
Conclusions – Care givers are increasingly turning to bottled water in an attempt to provide safe drinking water for their children. While this may represent a positive trend for
protecting children from water-transmitted diseases, it may represent an inefficient approach to safe drinking water provision that may place a financial burden on low-income families.
2 – Waste Manag. 2010 Jun;30(6):1138-48.
Solid waste workers and livelihood strategies in Greater Port-au-Prince, Haiti.
The University of the West Indies, Institute for Sustainable Development, Environmental Management Unit, 13 Gibraltar Camp Way, Mona Campus, Kingston, Jamaica. firstname.lastname@example.org
The solid waste management industry in Haiti is comprised of a formal and an informal sector. Many basic activities in the solid waste management sector are being carried out within the context of profound poverty, which exposes the failure of the socioeconomic and political system to provide sufficient job opportunities for the urban population. This paper examines the involvement of workers in the solid waste management industry in Greater Port-au-Prince and the implications for livelihood strategies. The findings revealed that the Greater Port-au-Prince solid waste management system is very inclusive with respect to age, while highly segregated with regard to gender. In terms of earning capacity, the results showed that workers hired by the State agencies were the most economically vulnerable group as more than 50% of them fell below the official nominal minimum wage. This paper calls for better salary scales and work compensation for the solid waste workers.
3 – J Water Health. 2010 Jun;8(2):355-64.
Assessment of E. coli and Salmonella spp. infection risks associated with different fecal sludge disposal practices in Thailand.
Yajima A, Koottatep T.
Department of Global Agricultural Science, Graduate School of Agricultural and Life Science, University of Tokyo, 1-1-1 Yayoi, Tokyo 113-8657, Japan. email@example.com
The proper management of fecal sludge (FS), to block the transmission pathways of pathogens, is rarely enforced in many parts of the world. Health risks associated with different disposal practices of FS in peri-urban settings of a large metropolis in Thailand were assessed; Tha Klong sub-district with indiscriminate FS dumping, and Klong Luang sub-district which has an FS treatment system. The study showed that indiscriminate FS dumping from along the canal banks and discharge of market waste were likely the major sources of E. coli and Salmonella spp. in contamination of the canal water. The increased microbial pathogen concentrations near the FS treatment facility also indicated contamination risks from poorly designed treatment facilities. Quantitative microbial risk assessment (QMRA) indicated very high water-related infection risk levels compared to the actual locally recorded disease occurrences. These results indicated that the QMRA model needs to be modified to take account of immunological differences between populations in developed countries, where the model was developed, and developing countries. In addition, further sensitivity factors are needed to reflect different societal behavior patterns, and therefore contact with
potentially contaminated water, in different sub-populations of many less developed communities.
4 – Epidemiol Infect. 2010 Jun 14:1-7.
Community perceptions of bloody diarrhoea in an urban slum in South Asia: implications for introduction of a Shigella vaccine.
Arvelo W, Blum LS, Nahar N, VON Seidlein L, Nahar L, Pack RP, Brooks AW, Pach A, Breiman RF, Luby SP, Ram PK. Centers for Disease Control and Prevention, Atlanta, GA, USA.
Understanding local perceptions of disease causation could help public health officials improve strategies to prevent bloody diarrhoea. A cross-sectional survey was conducted in Dhaka, Bangladesh to elicit community beliefs about the causes of and prevention strategies for bloody diarrhoea. Between March and June 2003, we interviewed 541 randomly selected respondents. Overall, 507 (93%) respondents perceived that a vaccine could prevent bloody diarrhoea. If a vaccine provided lifetime protection, 445 (83%) respondents
stated that they would opt to get the vaccine and would pay a median of $0.05 (range U.S.$0.01-0.15) for it, equivalent to <1% of their median weekly income. There was almost universal perception that an effective vaccine to prevent bloody diarrhoea was highly beneficial and acceptable. While respondents valued a vaccine for prevention of bloody diarrhoea, they were only willing to pay minimally for it. Therefore, achieving a high rate of Shigella vaccine coverage may require subsidy of vaccine purchase.
5 – AIDS Behav. 2010 Jun;14(3):721-30.
Community-based DOT-HAART accompaniment in an urban resource-poor setting.
Muñoz M, Finnegan K, Zeladita J, Caldas A, Sanchez E, Callacna M, Rojas C, Arevalo J, Sebastian JL, Bonilla C, Bayona J, Shin S. Socios En Salud Sucursal Perú, Lima, Peru.
From December 2005 to April 2007, we enrolled 60 adults starting antiretroviral therapy (ART) in a health district of Lima, Peru to receive community-based accompaniment with supervised antiretroviral (CASA). Paid community health workers performed twice-daily home visits to directly observe ART and offered additional medical, social and economic support to CASA participants. We matched 60 controls from a neighboring district by age, CD4 and primary referral criteria (TB status, female, neither). Using validated instruments at baseline and 12 months (time of DOT-HAART completion) we measured depression, social support, quality of life, HIV-related stigma and self-efficacy. We compared 12 month clinical and psychosocial outcomes among CASA versus control groups. CASA participants experienced better clinical and psychosocial outcomes at 12 months, including proportion with virologic suppression, increase in social support and reduction in HIV-associated stigma.
6 – AIDS. 2010 Jun 9.
Early immunologic response and subsequent survival among malnourished adults receiving antiretroviral therapy in Urban Zambia.
Koethe JR, Limbada MI, Giganti MJ, Nyirenda CK, Mulenga L, Wester CW, Chi BH, Stringer JS.
OBJECTIVE:: To evaluate the relationship between early CD4 lymphocyte recovery on antiretroviral therapy (ART) and subsequent survival among low body mass index (BMI) HIV-1-infected adults.
DESIGN:: Retrospective analysis of a large programmatic cohort in Lusaka, Zambia.
METHODS:: We evaluated ART-treated adults enrolled in care for more than 6 months. We stratified this study population according to World Health Organization (WHO) malnutrition criteria: normal (BMI >/=18.5 kg/m), mild (17.00-18.49), moderate (16.00-16.99), and severe (<16.0). We used Cox proportional hazards regression to estimate the subsequent risk of death associated with absolute CD4 cell count change over the first 6 months on ART. To account for effect modification associated with baseline CD4 cell count, a weighted summary measure was calculated.
RESULTS:: From May 2004 to February 2009, 56 612 patients initiated ART at Lusaka district clinics; of these, 33 097 (58%) were included in this analysis. The median change in 0-6 month CD4 cell count in each baseline BMI strata varied from 127 to 131 cells/mul. There was a statistically significant, inverse association between baseline BMI and the post 6-month hazard for mortality only among those patients with less than 100 cells/mul increase in the first 6 months of ART. A CD4 cell count increase of at least 100 cells/mul over the first 6 months of ART was not associated with a higher hazard for mortality, regardless of baseline BMI.
CONCLUSIONS:: Low baseline BMI and attenuated CD4 cell count response at 6 months had a compounding, negative impact on post 6-month survival. Specific guidelines for monitoring ART response using immunologic criteria may be warranted for low BMI patients.
7 – Arch Gynecol Obstet. 2010 Jun;281(6):991-4.
Obstetric and perinatal outcome in HIV positive women receiving HAART in urban Nigeria.
Olagbuji BN, Ezeanochie MC, Ande AB, Oboro VO.
Department of Obstetrics and Gynaecology, University of Benin Teaching Hospital, Benin, Edo State, Nigeria.
PURPOSE: To compare the outcome of pregnancy between HIV positive pregnant women on highly active antiretroviral therapy (HAART) and HIV negative controls.
METHODS: A prospective matched case-control study.
RESULTS: HIV positive women were significantly more likely to have anaemia in pregnancy [p < 0.001, odds ratio (95% CI) 5.66 (3.0-10.5)], intrauterine growth restriction [p = 0.002, odds ratio (95%CI) 13.82 (1.8-106.7)], preterm labour [p = 0.03, odds ratio (95% CI) 2.89 (1.2-7.0)] and birth weight less than 2,500 g [p < 0.0001, odds ratio (95% CI) 5.43 (2.4-12.0)]. The 5-min apgar score less than 7, admission into neonatal unit, stillbirth and perinatal mortality were comparable between the two groups.
CONCLUSION: Anaemia in pregnancy, intrauterine growth restriction, preterm labour and birth weight less than 2,500 g are important complications among HIV positive pregnant women. This information is vital for strategic antenatal care planning to improve obstetric and perinatal outcome in these women.
MALARIA AND OTHER VECTOR-BORNE DISEASES
8 – BMC Infect Dis. 2010 Jun 16;10(1):173.
Geographical and environmental approaches to urban malaria in Antananarivo (Madagascar).
Rakotomanana F, Ratovonjato J, Randremanana RV, Randrianasolo L, Raherinjafy R, Rudant JP, Richard V.
BACKGROUND: Previous studies, conducted in the urban of Antananarivo, showed low rate of confirmed malaria cases. We used a geographical and environmental approach to investigate the contribution of environmental factors to urban malaria in Antananarivo.
METHODS: Remote sensing data were used to locate rice fields, which were considered to be the principal mosquito breeding sites. We carried out supervised classification by the maximum likelihood method. Entomological study allowed vector species determination from collected larval and adult mosquitoes. Mosquito infectivity was studied, to assess the risk of transmission, and the type of mosquito breeding site was determined. Epidemiological data were collected from November 2006 to December 2007, from public health centres, to determine malaria incidence. Polymerase chain reaction was carried out on dried blood spots from patients, to detect cases of malaria. Rapid diagnostic tests were used to confirm malaria cases among febrile school children in a school survey. A geographical information system was constructed for data integration. Altitude, temperature, rainfall, population density and rice field surface area were analysed and the effects of these factors on the occurrence of confirmed malaria cases were studied.
RESULTS: Polymerase chain reaction confirmed malaria in 5.1% of the presumed cases. Entomological studies showed An. arabiensis as potential vector. Rice fields remained to be the principal breeding sites. Travel report was considered as related to the occurrence of P. falciparum malaria cases.
CONCLUSION: Geographical and environmental factors did not show direct relationship with malaria incidence but they seem ensuring suitability of vector development. Absence of relationship may be due to a lack of statistical power. Despite the presence of An. Arabiensis, scarce parasitic reservoir and rapid access to health care do not constitute optimal conditions to a threatening malaria transmission. However, imported malaria case is suggestive to sustain the pocket transmission in Antananarivo.
9 – Trans R Soc Trop Med Hyg. 2010 Jun;104(6):406-11.
Sand flies naturally infected by Leishmania (L.) mexicana in the peri-urban area of Chetumal city, Quintana Roo, México.
Sánchez-García L, Berzunza-Cruz M, Becker-Fauser I, Rebollar-Téllez EA. Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Medicina Experimental, Hospital General de México, Dr Balmis 148, Col. Doctores, México D.F. 06726, México. zinacla firstname.lastname@example.org
The surveillance of prevalent Leishmania sand fly vectors is an important issue for epidemiological studies in populated areas where leishmaniasis is endemic. In this study, we collected sand flies from a peri-urban area in the southeast of Mexico. Natural infection with Leishmania (L.) mexicana was studied by PCR using a Leishmania internal transcribed spacer of the ribosomal RNA gene for amplification. Infected Lutzomyia olmeca olmeca, Lu. shannoni and Lu. cruciata sand flies were collected mainly during the high transmission season (November to March), coinciding with the highest sand fly densities. Additionally, positive specimens of Lu. olmeca olmeca were also captured during July and August. The infected sand flies were from primary forest (subperennial forest) and secondary forest (18-25 years old and 10-15 years old respectively). Sand flies collected with Disney and Shannon traps were the ones found to be infected with L. (L.) mexicana. We conclude that the high-risk period in which L. (L.) mexicana is transmitted in the peri-urban area of Chetumal City is from July to March and that transmission is associated with both the subperennial forest and the secondary forest.
10 – Trop Med Int Health. 2010 Jun 1;15(6):762-71.
Prevalent high-risk respiratory hygiene practices in urban and rural Bangladesh.
Nasreen S, Azziz-Baumgartner E, Gurley ES, Winch PJ, Unicomb L, Sharker MA, Southern D, Luby SP. International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR,B), Dhaka, Bangladesh.
Objectives – To identify existing respiratory hygiene risk practices, and guide the development of interventions for improving respiratory hygiene.
Methods – We selected a convenience sample of 80 households and 20 schools in two densely populated communities in Bangladesh, one urban and one rural. We observed and recorded respiratory hygiene events with potential to spread viruses such as coughing, sneezing, spitting and nasal cleaning using a standardized assessment tool.
Results – In 907 (81%) of 1122 observed events, households’ participants coughed or sneezed into the air (i.e. uncovered), 119 (11%) into their hands and 83 (7%) into their clothing. Twenty-two per cent of women covered their coughs and sneezes compared to 13% of men (OR 2.6, 95% CI 1.6-4.3). Twenty-seven per cent of persons living in households with a reported monthly income of >72.6 US$ covered their coughs or sneezes compared to 13% of persons living in households with lower income (OR 3.2, 95% CI 1.6-6.2). In 956 (85%) of 1126 events, school participants coughed or sneezed into the air and 142 (13%) into their hands. Twenty-seven per cent of coughs/sneezes in rural schools were covered compared to 10% of coughs/sneezes in urban schools (OR 2.3, 95% CI 1.5-3.6). Hand washing was never observed after participants coughed or sneezed into their hands.
Conclusion – There is an urgent need to develop culturally appropriate, cost-effective and scalable interventions to improve respiratory hygiene practices and to assess their effectiveness in reducing respiratory pathogen transmission.
11 – BMC Gastroenterol. 2010 Jun 16;10(1):62.
Helicobacter pylori in apparently healthy children aged 0-12 years in urban Kampala, Uganda: a community-based cross sectional survey.
Hestvik E, Tylleskar T, Kaddu-Mulindwa DH, Ndeezi G, Grahnquist L, Olafsdottir E, Tumwine JK.
BACKGROUND: Helicobacter pylori is one of the most common causes of bacterial infection in human beings. Studies have showed a high prevalence of Helicobacter pylori among people in low-income countries and colonization early in life. A monoclonal antigen test, performed on faeces, HpSA(R)ImmunoCardSTAT, has a high sensitivity, specificity and accuracy and the faecal test can be performed in all ages, also in resource-limited settings. The main objective of this study was to determine the prevalence and factors associated with Helicobacter pylori colonization in apparently healthy children aged 0-12 years in urban Kampala, Uganda.
METHOD: We tested 427 apparently healthy children, age 0-12 years (211 males, 216 females), in a cross sectional survey for Helicobacter pylori colonization using HpSA(R)ImmunoCardSTAT. A short standardized interview with socio-demographic information and medical history was used to assess risk factors. RESULTS: The overall prevalence of Helicobacter pylori in the 427 children was 44.3 % (189 out of 427). Early colonization was common, 28.7 %, in children younger than 1 year of age. The age specific rates were 46.0 % in children age 1-<3 years, 51.7 % in children age 3-<6 years, 54.8 % in children age 6-<9 years and 40.0 % in children age 9-<12 years. There was a significant difference in prevalence by gender; female 38.5 % versus male 49.8 % and by type of housing; permanent house 38.5 % versus semi-permanent house 48.6 %. Congestive living and education level of the female caretaker showed a clear trend for a difference in prevalence. Factors independently associated with Helicobacter pylori colonization included: drugs taken last three months, using a pit latrine, sources of drinking water and wealth index.
CONCLUSION: The prevalence of Helicobacter pylori colonization among urban Ugandan children is high at an early age and increases with age. The impact of Helicobacter pylori colonization on children's health in Uganda needs to be further clarified.
12 – Parasitol Res. 2010 Jun 8.
Gastrointestinal and ectoparasites from urban stray dogs in Fortaleza (Brazil): high infection risk for humans?
Klimpel S, Heukelbach J, Pothmann D, Rückert S. Biodiversity and Climate Research Centre (BiK-F), Johann Wolfgang Goethe-University, Georg-Voigt-Str. 14-16, 60325, Frankfurt am Main, Germany, email@example.com.
Dogs are important definite or reservoir hosts for zoonotic parasites. However, only few studies on the prevalence of intestinal parasites in urban areas in Brazil are available. We performed a comprehensive study on parasites of stray dogs in a Brazilian metropolitan area. We included 46 stray dogs caught in the urban areas of Fortaleza (northeast Brazil). After euthanization, dogs were autopsied. Ectoparasites were collected, and the intestinal content of dogs were examined for the presence of parasites. Faecal samples were collected and analysed using merthiolate iodine formaldehyde concentration method.
A total of nine different parasite species were found, including five endoparasite (one protozoan, one cestode and three nematode species) and four ectoparasite species (two flea, one louse and one tick species). In the intestinal content, 3,162 specimens of four helminth species were found: Ancylostoma caninum (prevalence, 95.7%), Dipylidium caninum (45.7%), Toxocara canis (8.7%) and Trichuris vulpis (4.3%). A total of 394 ectoparasite specimens were identified, including Rhipicephalus sanguineus (prevalence, 100.0%), Heterodoxus spiniger (67.4%), Ctenocephalides canis (39.1%) and Ctenocephalides felis (17.4%). In the faeces, intestinal parasites were detected in 38 stray dogs (82.6%), including oocysts of Giardia sp. (2.2%) and eggs of the nematode A. caninum (82.6%). Neither eggs nor larval stages of D. caninum, T. canis or T. vulpis were detected in dog faeces. Sensitivity of faecal examination for A. caninum was 86.4% (95% confidence interval, 72.0-94.3) but zero percentage for the other intestinal helminth species.
Our data show that stray dogs in northeast Brazil carry a multitude of zoonotic ecto- and endoparasites, posing a considerable risk for humans. With the exception of A. caninum, sensitivity of faecal examination was negligible.
13 – Trop Med Int Health. 2010 Jun 1;15(6):664-72.
Spatial analysis of tuberculosis in an Urban West African setting: is there evidence of clustering?
Touray K, Adetifa IM, Jallow A, Rigby J, Jeffries D, Cheung YB, Donkor S, Adegbola RA, Hill PC. Bacterial Diseases Programme, MRC Laboratories, Banjul, The Gambia.
Objectives – To describe the pattern of tuberculosis (TB) occurrence in Greater Banjul, The Gambia with Geographical Information Systems (GIS) and Spatial Scan Statistics (SaTScan) and to determine whether there is significant TB case clustering.
Methods – In Greater Banjul, where 80% of all Gambian TB cases arise, all patients with TB registered at chest clinics between March 2007 and February 2008 were asked to participate. Demographic, clinical characteristics and GPS co-ordinates for the residence of each consenting TB case were recorded. A spatial scan statistic was used to identify purely spatial and space-time clusters of tuberculosis among permanent residents.
Results – Of 1145 recruited patients with TB, 84% were permanent residents with 88% living in 37 settlements that had complete maps available down to settlement level. Significant high- and low-rate spatial and space-time clusters were identified in two districts. The most likely cluster of high rate from both the purely spatial analysis and the retrospective space-time analysis were from the same geographical area. A significant secondary cluster was also identified in one of the densely populated areas of the study region.
Conclusions – There is evidence of significant clustering of TB cases in Greater Banjul, The Gambia. Systematic use of cluster detection techniques for regular TB surveillance in The Gambia may aid effective deployment of resources. However, passive case detection dictates that community-based active case detection and risk factor surveys would help confirm the presence of true clusters and their causes.