District-led malaria surveillance and response as an effective way to manage malaria upsurges following the withdrawal of indoor residual spraying: a case study from Nwoya District, northern Uganda.

BACKGROUND: Malaria remains the number one cause of morbidity and mortality in Uganda. In 2009, the United States President's Malaria Initiative (PMI) funded an indoor residual spraying (IRS) project in 10 mid-northern districts, resulting in marked reductions in malaria prevalence over 5 years, from 62.5 percent to 7.2 percent. When the project ended and IRS withdrawn, malaria prevalence increased exponentially to pre-IRS level of 63 percent in 2016 and was characterized by frequent life-threatening upsurges that were exacerbated by a weak national led malaria surveillance system with delayed and piece meal responses. Malaria Consortium, in collaboration with Nwoya district local government implemented a district led malaria surveillance and response system. This study was conducted to compare the impact of District led and national led surveillance and response systems on overall malaria burden in two sub-counties in Nwoya district, Northern Uganda. METHODS: The assessment was conducted between week 41 of 2018 and week 10 of 2019 in Anaka and Alero sub counties following the shift from the national to district led malaria surveillance and response system. A district multi-sectoral malaria response taskforce team, known as the District Malaria Surveillance and Response Team (DMSRT), was formed by the Nwoya District Health Team (DHT). The DMSRT was trained and equipped with new surveillance tools for early detection of and response to malaria upsurges within the district, and were mandated to develop a costed district specific malaria response plan. RESULTS: All (18) targeted health facilities provided weekly malaria reports and continuously updated the malaria normal channel graphs. There was an overall reduction in weekly new malaria cases from 12.9 in week 41 of 2018 to 6.2 cases in week 10 of 2019. Malaria positivity rates (TPR) for Alero and Anaka sub-counties reduced from 76.0 percent and 69.3 percent at week 42 of 2018 to 28 percent and 30.3 percent, respectively at week 10 of 2019. CONCLUSIONS: Malaria surveillance and response, with precisely targeted multipronged activities, when led and implemented by local district health authorities is an effective, efficient, and sustainable approach to prevent malaria upsurges and associated morbidity and mortality.

Transmission of Onchocerca volvulus by Simulium neavei in Mount Elgon focus of Eastern Uganda has been interrupted.

The study determined that Simulium neavei-transmitted onchocerciasis in Mount Elgon onchocerciasis focus had been interrupted. Annual mass treatment with ivermectin changed to two times per year along with vector elimination in 2007. Then, baseline microfilaria (mf) prevalence data of 1994 in five sentinel communities were compared with follow-up data in 2005 and 2011. Blood spots from 3,051 children obtained in 2009 were analyzed for Onchocerca volvulus immunoglobulin G4 antibodies. Fresh water crab host captures and blackflies collected indicated their infestation with larval stages of S. neavei and presence or absence of the vector, respectively. Mf rates dropped from 62.2% to 0.5%, and 1 (0.03%) of 3,051 children was positive for O. volvulus antibodies. Crab infestation dropped from 41.9% in 2007 to 0%, and S. neavei biting reduced to zero. Both remained zero for the next 3 years, confirming interruption of onchocerciasis transmission, and interventions were halted.