Spatial point analysis based on dengue surveys at household level in central Brazil

<p>Abstract</p> <p>Background</p> <p>Dengue virus (DENV) affects nonimunne human populations in tropical and subtropical regions. In the Americas, dengue has drastically increased in the last two decades and Brazil is considered one of the most affected countries. The high frequency of asymptomatic infection makes difficult to estimate prevalence of infection using registered cases and to locate high risk intra-urban area at population level. The goal of this spatial point analysis was to identify potential high-risk intra-urban areas of dengue, using data collected at household level from surveys.</p> <p>Methods</p> <p>Two household surveys took place in the city of Goiania (~1.1 million population), Central Brazil in the year 2001 and 2002. First survey screened 1,586 asymptomatic individuals older than 5 years of age. Second survey 2,906 asymptomatic volunteers, same age-groups, were selected by multistage sampling (census tracts; blocks; households) using available digital maps. Sera from participants were tested by dengue virus-specific IgM/IgG by EIA. A Generalized Additive Model (GAM) was used to detect the spatial varying risk over the region. Initially without any fixed covariates, to depict the overall risk map, followed by a model including the main covariates and the year, where the resulting maps show the risk associated with living place, controlled for the individual risk factors. This method has the advantage to generate smoothed risk factors maps, adjusted by socio-demographic covariates.</p> <p>Results</p> <p>The prevalence of antibody against dengue infection was 37.3% (95%CI [35.5–39.1]) in the year 2002; 7.8% increase in one-year interval. The spatial variation in risk of dengue infection significantly changed when comparing 2001 with 2002, (ORadjusted = 1.35; p < 0.001), while controlling for potential confounders using GAM model. Also increasing age and low education levels were associated with dengue infection.</p> <p>Conclusion</p> <p>This study showed spatial heterogeneity in the risk areas of dengue when using a spatial multivariate approach in a short time interval. Data from household surveys pointed out that low prevalence areas in 2001 surveys shifted to high-risk area in consecutive year. This mapping of dengue risks should give insights for control interventions in urban areas.</p

Pervasive antibiotic misuse in the Cambodian community: antibiotic-seeking behaviour with unrestricted access

Abstract Background Antibiotic misuse is widespread in resource-limited countries such as Cambodia where the burden of infectious diseases is high and access to antibiotics is unrestricted. We explored healthcare seeking behaviour related to obtaining antibiotics and drivers of antibiotic misuse in the Cambodian community. Methods In-depth interviews were held with family members of patients being admitted in hospitals and private pharmacies termed pharmacy attendants in the catchment areas of the hospitals. Nurses who run community primary healthcare centres located within the hospital catchment areas were invited to attend focus group discussions. Nvivo version 10 was used to code and manage thematic data analysis. Results We conducted individual interviews with 35 family members, 7 untrained pharmacy attendants and 3 trained pharmacists and 6 focus group discussions with 30 nurses. Self-medication with a drug-cocktail was widespread and included broad-spectrum antibiotics for mild illness. Unrestricted access to antibiotics was facilitated by various community enablers including pharmacies or drug outlets, nurse suppliers and unofficial village medical providers referred to as “village Pett” whose healthcare training has historically been in the field and not at university. These enablers supplied the community with various types of antibiotics including broad spectrum fluoroquinolones and cephalosporins. When treatment was perceived to be ineffective patients would prescriber-shop various suppliers who would unfailingly provide them with antibiotics. The main driver of the community’s demand for antibiotics was a mistaken belief in the benefits of antibiotics for a common cold, high temperature, pain, malaria and ‘Roleak’ which includes a broad catch-all for perceived inflammatory conditions. For severe illnesses, patients would attend a community healthcare centre, hospital, or when their finances permitted, a private prescriber. Conclusions Pervasive antibiotic misuse was driven by a habitual supplier-seeking behaviour that was enabled by unrestricted access and misconceptions about antibiotics for mild illnesses. Unofficial suppliers must be stopped by supporting existing regulations with tough new laws aimed at outlawing supplies outside registered pharmacies and fining registered pharmacist/owners of these pharmacies for supplying antibiotics without a prescription. Community primary healthcare centres must be strengthened to become the frontline antibiotic prescribers in the community thereby enabling the community’s access to inexpensive and appropriate healthcare. Community-based education program should target appropriate health-seeking pathways and the serious consequences of antibiotic misuse

Detection of dengue virus serotype 3 by reverse transcription-polymerase chain reaction in Aedes aegypti (Diptera, Culicidae) captured in Manaus, Amazonas

The detection of dengue virus serotypes from Aedes aegypti in Manaus, state of Amazonas was carried out using the reverse transcription-polymerase chain reaction technique. Fourteen pools out 82 (17.1%) were positive for DENV3, providing a minimal infection rate of 2.1% of all analyzed infected female specimens of three different areas of the city

Some southern African plant species used to treat helminth infections in ethnoveterinary medicine have excellent antifungal activities

<p>Abstract</p> <p>Background</p> <p>Diseases caused by microorganisms and parasites remain a major challenge globally and particularly in sub-Saharan Africa to man and livestock. Resistance to available antimicrobials and the high cost or unavailability of antimicrobials complicates matters. Many rural people use plants to treat these infections. Because some anthelmintics e.g. benzimidazoles also have good antifungal activity we examined the antifungal activity of extracts of 13 plant species used in southern Africa to treat gastrointestinal helminth infections in livestock and in man.</p> <p>Methods</p> <p>Antifungal activity of acetone leaf extracts was determined by serial microdilution with tetrazolium violet as growth indicator against <it>Aspergillus fumigatus, Cryptococcus neoformans</it> and <it>Candida albicans</it>. These pathogens play an important role in opportunistic infections of immune compromised patients. Cytotoxicity was determined by MTT cellular assay. Therapeutic indices were calculated and selectivity for different pathogens determined. We proposed a method to calculate the relation between microbicidal and microbistatic activities. Total activities for different plant species were calculated.</p> <p>Results</p> <p>On the whole, all 13 extracts had good antifungal activities with MIC values as low as 0.02 mg/mL for extracts of <it>Clausena anisata</it> against <it>Aspergillus fumigatus a</it>nd 0.04 mg/mL for extracts of <it>Zanthoxylum capense, Clerodendrum glabrum,</it> and <it>Milletia grandis</it>, against <it>A. fumigatus. Clausena anisata</it> extracts had the lowest cytotoxicity (LC₅₀) of 0.17 mg/mL, a reasonable therapeutic index (2.65) against <it>A. fumigatus</it>. It also had selective activity against <it>A. fumigatus</it>, an overall fungicidal activity of 98% and a total activity of 3395 mL/g against <it>A. fumigatus</it>. This means that 1 g of acetone leaf extract can be diluted to 3.4 litres and it would still inhibit the growth. <it>Clerodendrum glabrum, Zanthoxylum capense</it> and <it>Milletia grandis</it> extracts also yielded promising results.</p> <p>Conclusions</p> <p>Some plant extracts used for treatment of parasitic infections also have good antifungal activity. Because it is much easier to isolate antifungal compounds by bioassay guided fractionation, this approach may facilitate the isolation of anthelmintic compounds from active plant extracts. The viability of this approach can be tested by isolating the antifungal compounds and then determining its anthelmintic activity. Some of these plant extracts may also be useful in combating fungal infections.</p