Box 12.2Challenges to Elimination: Select Examples

Despite the recent successes in eliminating malaria, challenges remain. The following discussion highlights these challenges and provides examples of some actions taken to overcome them:

• Lack of sustained funding. India implemented a widely successful program through DDT spraying that reduced the malaria burden from an estimated 100 million annual cases in the early 1900s to about 100,000 cases in 1965. However, when U.S. assistance ended, India was unable to maintain its vector control activities. Resurgence over the next decade led to nearly 6 million cases. A key priority identified in India’s current National Framework for Malaria Elimination 2016–2030 is funding its elimination plan with sustained domestic resources and innovative financing models, including cost-sharing partnerships and integration with other government departments (Government of India 2016).^a
• Political instability and conflict. By 1975, malaria was eliminated throughout the former Soviet Union. However, after its collapse in the early 1990s, efforts were disrupted by a lack of funding. Civil wars broke out in several of the former territories, such as Azerbaijan and Tajikistan, contributing to resurgence and reintroduction. Overall strengthening of national health systems and creation of national malaria control programs in 1998 and 1997, respectively, after gaining independence and achieving political stability allowed the malaria situation to be brought under control rapidly in both countries.
• Weak program vigilance. Mauritius achieved malaria-free certification in 1973. However, when the program was integrated into preventive health services, the malaria surveillance system was weakened. Vector control activities and screening were reduced, contributing to resurgence associated with an influx of migrant workers. Through the combination of an active surveillance program that screened visitors from malarious areas, an integrated vector management strategy, and a strong health system for detecting and responding to missed cases of imported or introduced malaria, Mauritius has remained malaria free since 1998.
• Drug and insecticide resistance. With few replacement options, drug and insecticide resistance is a major threat to elimination. Multidrug resistance emerged and spread rapidly within and outside the Greater Mekong subregion (Cambodia, the Lao People’s Democratic Republic, Myanmar, Thailand, Vietnam, and China’s Yunnan Province), threatening effective treatment everywhere. In the Greater Mekong subregion, the WHO is leading an urgent, multipartner effort to eliminate P. falciparum transmission by 2025.
  At the same time, resistance to pyrethroids, the active ingredients used in insecticide-treated nets, is expanding rapidly in Sub-Saharan Africa. In 2014, 27 countries had reported insecticide resistance (Strode and others 2014). To combat insecticide resistance, the Innovative Vector Control Consortium and UNITAID have recently partnered to improve access to new insecticides for indoor residual spraying in 16 countries across Africa. Their US$65 million Next Generation Indoor Residual Spray Project will work with multiple partners to make alternative insecticides more affordable.
• Importation. Four countries in southern Africa—Botswana, Namibia, South Africa, and Swaziland—are seeking to eliminate indigenous transmission within the next five years, but many of their neighbors have much higher malaria burdens. Mobile (moving within a country or coming back from abroad) and migrant (coming from elsewhere into the area) populations are primary sources of imported cases, driving secondary transmission. As a result, the number of cases and deaths between 2012 and 2013 rose in all four countries. Cross-border initiatives are essential to addressing these challenges.
  In September 2015, the Global Fund approved US$17.8 million for the eight countries in southern Africa (Angola, Botswana, Mozambique, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe) termed the “Elimination 8” or “E8,” designed to serve as a platform for joint planning, negotiation, and accountability toward a regionally synchronized malaria elimination effort. The main thrust of the E8 regional program is to expand access to early diagnosis and treatment for mobile and underserved populations and to enhance surveillance in the border areas.
• Weak health systems and program capacity. The Solomon Islands and Vanuatu have had difficulty maintaining robust malaria elimination programs as a result of weak health systems and limited program capacity to deliver effective diagnosis and treatment to populations in remote areas. Both have experienced periodic spikes in cases that have proved challenging to bring under control.

Sources: Cohen and others 2012; Manguin, Carnevale, and Mouchet 2008; Tatarsky and others 2011.

a. Sustaining domestic and international funding as the malaria burden declines is a serious concern for most malaria-eliminating countries, 15 of which are now upper-middle income and thus no longer eligible for donor funding.