Overview of malaria elimination
Malaria elimination is the interruption of local mosquito-borne malaria transmission, i.e. the reduction to zero of the incidence of malaria infection in a defined geographical area. From a country perspective, elimination of malaria is the ultimate goal of malaria control. After elimination, continued measures are required to prevent re-establishment of transmission. Malaria eradication is defined as the permanent reduction to zero of the worldwide incidence of malaria infection caused by a particular malaria parasite species.
At present, 10 of the 95 countries and territories with ongoing malaria transmission are classified by WHO as being in the malaria elimination phase. These are: Algeria, Argentina, China, Costa Rica, the Islamic Republic of Iran, Paraguay, the Republic of Korea, Saudi Arabia, Tajikistan and Turkey. Ten countries are in pre-elimination phase, and 9 are working to prevent re-introduction of the disease. In recent years, 5 countries have been certified by WHO as having eliminated malaria: the United Arab Emirates (2007), Morocco (2010), Turkmenistan (2010), Armenia (2011) and Maldives (2015).
Sustained political commitment, adequate resourcing and effective partnerships are all fundamental to the success of malaria elimination programmes.
Path to malaria elimination
The path towards malaria-free status is characterized by four distinct programme phases: control, pre-elimination, elimination and prevention of reintroduction. Each phase is defined by a set of specific programme interventions needed for prevention, treatment, surveillance, monitoring and evaluation and health systems strengthening. Every year, the World Malaria Report includes an updated classification of countries by elimination programme stage. Progression between stages is determined by a set of programmatic and epidemiological criteria, and countries may elect to adopt a phased elimination strategy, either by parasite species or by geographical area.
Moving from the control to the elimination phase requires an updating of strategies. The main objective of malaria control is reducing malaria cases and deaths by providing access to preventive methods, diagnostic testing and treatment to the entire population at risk. During the elimination phase, malaria is no longer considered to be a significant public health concern, and programmes become more focused on reducing malaria transmission in a few specific regions. At this stage, interventions focus on detecting all malaria cases, preventing onward transmission, managing malaria foci, and managing imported malaria cases.
To minimize the period of intensive field operations, malaria elimination is usually undertaken as a time-limited programme. Even in the most ideal operational environments, a minimum period of 8-10 years is required to achieve elimination in any given area with ongoing transmission. Importation of malaria by international travellers carries the risk of resumption of transmission, as does the frequent decline in political support for malaria efforts when a programme is successful. It is critical to ensure political and financial commitment to maintaining malaria-free status; failure to do so can have not only public health but economic consequences, linked to decreases in tourism and business investments.
Official register of malaria-free countries
Since the early 1960s, WHO has maintained an official Register of areas where malaria elimination has been achieved. WHO also maintains a Supplementary list to the official register, listing countries where malaria never existed or disappeared years or decades ago, and where full WHO certification of malaria elimination would not be needed. WHO published the first supplementary list in 1963 including 23 countries. The most recent list was published in the World Malaria Report 2012 and included 62 countries.
- Eliminating malaria (2016)
- World Malaria Report 2015
- Disease surveillance for malaria control and elimination: operational manuals (2012)
- Community-based reduction of malaria transmission (2012)
- Malaria elimination: a field manual for low and moderate endemic countries (2007)