Economics &Indoor Residual Spraying &IRS Bill Brieger | 16 Nov 2020 06:43 am
Epidemiological and Projected Economical Impact of Indoor Residual Spraying in Ngoma District, Rwanda
This year the Annual Meeting of the American Society of Tropical Medicine and Hygiene is virtual. We will feature some of the abstracts over the coming week. Our first selection from the 69th meeting is a study from Rwanda on indoor residual spraying by Michee S. Kabera (see author list and affiliations at end) wherein we learn about the benefits of averting malaria cases.
IRS in Ngoma District
Malaria remains a major public health problem and is among the leading causes of morbidity and mortality in Rwanda. Indoor Residual Spraying (IRS) is a core vector control intervention in Rwanda that supplement Insecticide-treated bed nets (ITNs). Ngoma district is located in Eastern province of Rwanda bordering with Burundi in South. The first IRS round was conducted in the above district in April 2019 (before the high peak season of May-June) with the support of the Government of Rwanda and The Global Funds.
The IRS coverage rate was 98.9% with a protected population of 357,058 using “Pirimiphos methyl 300 CS. Using RHMIS, we compared malaria cases respectively reported for a period of 12 months before IRS (April 2018 to March 2019) and after IRS (April 2019 to March 2020). The total number of uncomplicated malaria cases was significantly dropped down by 82%, from 581,742 before IRS to 105,120 cases after IRS. The incidence per 1000 inhabitants decreased from 1,502 to 265 respectively.
Moreover, the inpatient cases also significantly decreased by 87.7%, from 1037 before IRS to 170 cases after IRS. The cost of conducting IRS in Ngoma district was USD 2,104,007 including both the cost for Insecticides and operation. The invested cost per averted malaria case was USD 4.4. Using the minimum average cost of USD 8.6 for treating an episode of the disease including direct cost and the opportunity costs of travel and waiting time (1,2); the total benefit due to averted malaria cases is estimated to USD 4,132,313.
Applying the average cost for inpatient malaria case which is estimated to USD US$60.44 (4), the benefit due to the averted malaria inpatient cases is equal to USD 52,401. The total benefit for averted outpatients and inpatients is estimated to USD 4,184,714. In conclusion, there was a significant decrease of out and inpatient malaria cases just one year after IRS in Ngoma district.
Furthermore, if we compare the IRS expenditures and the benefits related to the averted malaria cases, there was an important cost benefit. We expect more economic impact as malaria cases may continue to decrease.
Authors and Affiliations
Michee S. Kabera(1), Noella Noella(2), Emmanuel Hakizimana(1), Dunia Munyakanage(1), Jean Louis Mangala(1), Kaendi Munguti(3), Aimable Mbituyumuremyi(1) 1.Rwanda Biomedical Center, Kigali, Rwanda, 2.JHPIEGO, Kigali, Rwanda, 3.President’s Malaria Initiative, Kigali, Rwanda