Bangladesh government's commitment '100% sanitation by 2010' : from myth to reality

In spite of widespread access to microbiologically safe drinking water the limited access to sanitation has undermined the expected health impact in Bangladesh. In 2003 the Bangladesh Government set a target of 100% sanitation by 2010, sharply ahead of the Millennium Development Goals target. Following the declaration of the Government’s commitment, a base line survey was conducted involving Central Government, the Local Government Institutions, NGOs, development partners and communities. The survey revealed that only 33% of households were using a sanitary latrine. The Government’s initiatives including the formation of a Task Force involving different administrative tiers, supporting the LGI adoption of pro-poor strategies, observation of a sanitation month, media campaigns, and the introduction of award system has dramatically raised the sanitation coverage to 78% by June 2006. This remarkable achievement gives rise to a sense of optimism that the target of 100% sanitation will be reached even before 2010

Descriptive analysis of the study sample (n = 17,842): Categorical and continuous variables.

Descriptive analysis of the study sample (n = 17,842): Categorical and continuous variables.</p

Bivariate and multivariate logistic regression analysis to determine the association of women’s dietary diversity score (DDS), women’s empowerment, and some socio-demographic factors (n = 17,842).

Bivariate and multivariate logistic regression analysis to determine the association of women’s dietary diversity score (DDS), women’s empowerment, and some socio-demographic factors (n = 17,842).</p

Phylogenetic tree of 246 <i>gag</i>-sequences, including 118 Bangladeshi HIV-1 C strains in green.

<p>The HIV1-C strains found in Bangladesh do not fall into a country specific clade, instead our results point to repeated introductions with substantial in-country transmission only among PWIDs. Four clades with ≥3 BD strains had a posterior probability of around 0.7 or higher, and are shown in the figure. <b><i>Clade</i><i> 1</i></b> is a monophyletic clade of 47 BD strains, of which 43 originate from PWIDs in Dhaka. The tMRCA of this clade is around 1975. It is a subset of the large regional <b><i>Clade</i><i> 2</i></b>, which is dominated by strains from Bangladesh, Myanmar, India and China. Over 80% of all BD strains can be found within this clade, which appears to have been introduced to this region around 1962. The intermixing of sequences collected from different countries indicates frequent cross-border transmission in this region. In addition to the 47 strains in Clade 1, the BD strains in Clade 2 includes sequences from returning migrants from Nepal, India and the Middle East as well as some weakly supported clades of strains from sex workers and VCT/STI patients. <b><i>Clade</i><i> 3</i></b> consists of seven PWID strains from Dhaka, and the short branches in this clade reveal rapid transmission (and detection) within this group. <b><i>Clade</i><i> 4</i></b> contains five strains from VCT visitors in Dhaka and Chittagong, at least 3 of whom had a history of migrant work in the Middle East. The long branches show that they are not very close genetically and it is possible that they represent separate introductions of related strains. Most of the BD strains found outside these clades appear to represent separate introductions.</p

<i>Vibrio cholerae</i> Persisted in Microcosm for 700 Days Inhibits Motility but Promotes Biofilm Formation in Nutrient-Poor Lake Water Microcosms

<div><p>Toxigenic <i>Vibrio cholerae</i>, ubiquitous in aquatic environments, is responsible for cholera; humans can become infected after consuming food and/or water contaminated with the bacterium. The underlying basis of persistence of <i>V. cholerae</i> in the aquatic environment remains poorly understood despite decades of research. We recently described a “persister” phenotype of <i>V. cholerae</i> that survived in nutrient-poor “filter sterilized” lake water (FSLW) in excess of 700-days. Previous reports suggest that microorganisms can assume a growth advantage in stationary phase (GASP) phenotype in response to long-term survival during stationary phase of growth. Here we report a <i>V. cholerae</i> GASP phenotype (GASP-700D) that appeared to result from 700 day-old persister cells stored in glycerol broth at −80°C. The GASP-700D, compared to its wild-type N16961, was defective in motility, produced increased biofilm that was independent of <i>vps</i> (p<0.005) and resistant to oxidative stress when grown specifically in FSLW (p<0.005). We propose that <i>V. cholerae</i> GASP-700D represents cell populations that may better fit and adapt to stressful survival conditions while serving as a critical link in the cycle of cholera transmission.</p></div

Resistance of GASP-700D to oxidative (H₂O₂) stress.

<p><i>V. cholerae</i> strains N16961S-24, N16961R-24 and GASP-700D were grown (ca. 10⁸ cfu/ml) in FSLW supplemented with 20 mM H₂O₂. The cultures were examined at 5 min interval for 15 min for the presence of culturable bacteria as determined by standard plate count. Error bars indicate means ± standard deviation (SD) from triplicate experiments. The stress resistance of each strain was compared with that of N1961S-24 using one-way ANOVA test. A p-value of <0.005 was considered statistically significant.</p

Resistance of GASP-700D to oxidative (H₂O₂) stress.

<p><i>V. cholerae</i> strains N16961S-24, N16961R-24 and GASP-700D were grown (ca. 10⁸ cfu/ml) in FSLW supplemented with 20 mM H₂O₂. The cultures were examined at 5 min interval for 15 min for the presence of culturable bacteria as determined by standard plate count. Error bars indicate means ± standard deviation (SD) from triplicate experiments. The stress resistance of each strain was compared with that of N1961S-24 using one-way ANOVA test. A p-value of <0.005 was considered statistically significant.</p

Colony morphology and associated biofilms (measured quantitatively) produced by each <i>V. cholerae</i> strain.

<p>(A) Colony morphology: each <i>V. cholerae</i> strain was subcultured on L-agar and incubated overnight at 37°C before images were acquired; (B) Quantitative measurement of biofilm produced by each <i>V. cholerae</i> strain in nutrient-rich L-broth; and (C) Quantitative measurement of biofilm produced by each <i>V. cholerae</i> strain in nutrient-poor FSLW. All the values are expressed as means ± standard deviation (SD) from at least triplicate experiments. P-values are computed by comparing the biofilm formation of each strain with that of N1961S-24 using one-way ANOVA test. A p-value of <0.005 was considered statistically significant.</p

Bacterial strains and plasmids used in this study.

<p>Bacterial strains and plasmids used in this study.</p

Topography and architecture of <i>V. cholerae</i> biofilms.

<p>Each strain was grown in a 4-well cell culture plate containing 500 μl FSLW. A glass cover slip was dipped into each culture well and incubated overnight statically at room temperature. The glass cover slips were stained with SYTO 9 and the images were obtained using a laser scanning confocal microscopy with an excitation and emission wavelengths of 484 and 500 nm, respectively. (A) Images of x–y sections (top panels) and x–z projections of the same biofilms (bottom panels) were analyzed with DAIME software; magnification, x200. (B) Average biofilm heights (μm) for each strain measured across five random x–z sections. (C) Total volume of biofilm (μm³) for each strain calculated by x–y and x–z projections. A p-value of <0.005 was considered statistically significant.</p