Validation of a screening tool to identify older children living with HIV in primary care facilities in high HIV prevalence settings.

OBJECTIVE: We previously proposed a simple tool consisting of five items to screen for risk of HIV infection in adolescents (10-19 years) in Zimbabwe. The objective of this study is to validate the performance of this screening tool in children aged 6-15 years attending primary healthcare facilities in Zimbabwe. METHODS: Children who had not been previously tested for HIV underwent testing with caregiver consent. The screening tool was modified to include four of the original five items to be appropriate for the younger age range, and was administered. A receiver operator characteristic analysis was conducted to determine a suitable cut-off score. The sensitivity, specificity and predictive value of the modified tool were assessed against the HIV test result. RESULTS: A total of 9568 children, median age 9 (interquartile, IQR: 7-11) years and 4971 (52%) men, underwent HIV testing. HIV prevalence was 4.7% (95% confidence interval, CI:4.2-5.1%) and increased from 1.4% among those scoring zero on the tool to 63.6% among those scoring four (P < 0.001). Using a score of not less than one as the cut-off for HIV testing, the tool had a sensitivity of 80.4% (95% CI:76.5-84.0%), specificity of 66.3% (95% CI:65.3-67.2%), positive predictive value of 10.4% and a negative predictive value of 98.6%. The number needed to screen to identify one child living with HIV would drop from 22 to 10 if this screening tool was used. CONCLUSION: The screening tool is a simple and sensitive method to identify children living with HIV in this setting. It can be used by lay healthcare workers and help prioritize limited resources.

Distribution of schistosomiasis and soil transmitted helminthiasis in Zimbabwe: towards a national plan of action for control and elimination.

BACKGROUND: Schistosomiasis and STH are among the list of neglected tropical diseases considered for control by the WHO. Although both diseases are endemic in Zimbabwe, no nationwide control interventions have been implemented. For this reason in 2009 the Zimbabwe Ministry of Health and Child Care included the two diseases in the 2009-2013 National Health Strategy highlighting the importance of understanding the distribution and burden of the diseases as a prerequisite for elimination interventions. It is against this background that a national survey was conducted. METHODOLOGY: A countrywide cross-sectional survey was carried out in 280 primary schools in 68 districts between September 2010 and August 2011. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni and STH (hookworms, Trichuris trichiura, Ascaris lumbricoides) were diagnosed using both the Kato Katz and formol ether concentration techniques. MAIN FINDINGS: Schistosomiasis was more prevalent country-wide (22.7%) than STH (5.5%). The prevalence of S. haematobium was 18.0% while that of S. mansoni was 7.2%. Hookworms were the most common STH with a prevalence of 3.2% followed by A. lumbricoides and T. trichiura with prevalence of 2.5% and 0.1%, respectively. The prevalence of heavy infection intensity as defined by WHO for any schistosome species was 5.8% (range 0%-18.3% in districts). Only light to moderate infection intensities were observed for STH species. The distribution of schistosomiasis and STH varied significantly between provinces, districts and schools (p<0.001). Overall, the prevalence of co-infection with schistosomiasis and STH was 1.5%. The actual co-endemicity of schistosomiasis and STH was observed in 43 (63.2%) of the 68 districts screened. CONCLUSION AND RECOMMENDATIONS: This study provided comprehensive baseline data on the distribution of schistosomiasis and STH that formed the basis for initiating a national control and elimination programme for these two neglected tropical diseases in Zimbabwe.