Cross-sectional community-based study of the socio-demographic factors associated with the prevalence of dengue in the eastern part of Sudan in 2011.

BACKGROUND: Dengue is caused by an arthropod-borne flavivirus. Infection can be either primary or secondary based on serology, with each stage of the disease characterized by specific serological conversion and antibody formation. Further study is needed to fully identify the factors associated with and predisposing to dengue infection. The objective of this study was to identify socio-demographic factors associated with the prevalence of dengue serotypes in Kassala State in the eastern part of Sudan in 2011. METHODS: This was a cross-sectional community-based study with 530 participants who were randomly selected through multi-stage cluster sampling. Dengue serotype prevalence was determined using capture Enzyme-linked immunosorbent assay (ELISA). ELISA IgG. A multivariate logistic regression model was designed to measure the strength of associations between socio-demographic factors and dengue serotype prevalence. All participants who tested negative for dengue were used as the statistical reference group. RESULTS: From this study, the prevalence of dengue in Kassala was estimated to be 9.4% (95% CI: 7.1-12.3). Lack of knowledge about dengue fever disease (OR 2.8, 95% CI: 1.24-6.53) and a household density of more than 3 people per room (OR 2.1, 95% CI: 1.06-4.09) were the most important factors associated with dengue infection among the study population. CONCLUSIONS: Community-oriented interventions are needed to modify existing social behaviors to reduce the risk of dengue in the eastern part of Sudan. Additional studies are also required in this field.

Sero-prevalence of dengue infections in the Kassala state in the eastern part of the Sudan in 2011.

Dengue fever is a vector-borne disease that is transmitted to humans by infected Aedes aegypti mosquitoes. The eastern part of the Sudan is one of the regions that is affected by dengue virus circulation. In this study, we estimated the prevalence of dengue infections in the Kassala state in the eastern part of the Sudan. The study objective was to estimate the sero-prevalence of dengue IgG/IgM antibodies in the Kassala locality in 2011. This was a cross sectional community-based study that utilized a multi-stage cluster sampling technique regarding the probability sampling the study participants. Capture ELISA serological techniques were used for both IgM and IgG, with the specific cut-offs for each set by the manufacturer. The prevalence of dengue infection was found to be 9.4% (95% CI: 7.1-12.3). In conclusion, there is evidence that the dengue virus is being transmitted in Kassala. Disease surveillance, including the clinical, serological and entomological components, should be strengthened, and additional epidemiological studies are needed to better understand of the disease burden and effects in the area.

Factors associated with dengue fever IgG sero-prevalence in South Kordofan State, Sudan, in 2012: Reporting prevalence ratios.

BACKGROUND: Dengue fever (DF) is a vector-borne virus transmitted to humans by infected Aedes mosquitoes. In this study, we identified the most important factors associated with the prevalence of IgG antibodies in a border state between Sudan and the new republic of South Sudan. OBJECTIVES: To quantify the association of specific factors with the prevalence of DF IgG antibodies in Lagawa among subjects aged 16-60 years in 2012. METHODOLOGY: Analytical cross-sectional community-based study conducted in Lagawa in 2012. RESULTS: Indoor mosquito breeding was the most significant predictor affecting DF IgG serology. Household water storage was also strongly associated with the presence of IgG antibodies. Residence in urban areas, younger age and a history of travel to the Red Sea State were significant predictors of DF IgG seroprevalence in South Kordofan state. CONCLUSION: Indoor (household) behaviors associated with DF infection should be modified to mitigate the infection risk in the study area. Awareness should be raised regarding DF in Lagawa to ensure community participation in all control measures, and the surveillance system at the border between Sudan and the republic of South Sudan should be strengthened.

Testing the sensitivity and specificity of the fluorescence microscope (Cyscope) for malaria diagnosis.

BACKGROUND: Early diagnosis and treatment of malaria are necessary components in the control of malaria. The gold standard light microscopy technique has high sensitivity, but is a relatively time-consuming procedure especially during epidemics and in areas of high endemicity. This study attempted to test the sensitivity and specificity of a new diagnostic tool - the Cyscope fluorescence microscope, which is based on the use of Plasmodium nucleic acid-specific fluorescent dyes to facilitate detection of the parasites even in low parasitaemia conditions due to the contrast with the background. METHODS: In this study, 293 febrile patients above the age of 18 years attending the malaria treatment centre in Sinnar State (Sudan) were interviewed using a structured questionnaire. Finger-prick blood samples were also collected from the participants to be tested for malaria using the hospital's microscope, the reference laboratory microscope, as well as the Cyscope microscope. The results of the investigations were then used to calculate the sensitivity, specificity, and positive and negative predictive values of the Cyscope microscope in reference to gold standard light microscopy. RESULTS: The sensitivity was found to be 98.2% (95% CI: 90.6%-100%); specificity = 98.3% (95% CI: 95.7% - 99.5%); positive predictive value = 93.3% (95% CI: 83.8% - 98.2%); and negative predictive value = 99.6% (95% CI: 97.6% - 100%). CONCLUSIONS: In conclusion, the Cyscope microscope was found to be sensitive, specific and provide rapid, reliable results in a matter of less than 10 minutes. The Cyscope microscope should be considered as a viable, cheaper and time-saving option for malaria diagnosis, especially in areas where Plasmodium falciparum is the predominant parasite.

Retention and efficacy of long-lasting insecticide-treated nets distributed in eastern Sudan: a two-step community-based study.

BACKGROUND: In order to assess the effectiveness of long-lasting insecticide-treated nets (LLINs) as a method for malaria control, there is a need to determine how high is the retention of bed nets, how they are utilized, and how efficacious they are against the mosquitoes that transmit the disease. This is especially important in case of Sudan after emergence of resistance to pyrethroids in use. METHODS: This two-step study aimed to assess the retention and efficacy of LLINs (Olysettrade mark) distributed in the year 2006 in Kassala district in eastern Sudan. In the first step, using a cluster sample technique, heads of 210 households (30 by 7) were interviewed, and six LLINs were collected and later tested for efficacy. In the second step, eight focus group discussion sessions were conducted to complement the results from the first step. RESULTS: Results showed that the retention of LLINs was 92.9% one-and-half years after distribution. Some bed nets were distributed against a price. Utilization of bed nets by children under five years of age and by pregnant women was found to be 55% and 42.1% respectively. For the bioassay efficacy tests, mean knock down after 60 minutes was 91.1%, while mortality after 24 hours was 99.4%. CONCLUSION: LLINs (Olysettrade mark) were efficacious at the time of the study. People appreciated the usefulness but were not fully aware of their importance and were not motivated enough to use them. The retention of the bed nets was quite high but the utilization of the nets needs more focus from the National Malaria Control Programme. Bed net distribution activities should be accompanied by wide health education campaigns and followed up with tracking surveys to evaluate their effectiveness.