"Eeeeee", the familiar high-pitched sound one hears when a mosquito flies near our ears, and we bat it away irritatedly. One of these mosquitoes could be the Anopheles species, which is the carrier of Plasmodium parasites that cause the life-threatening disease, malaria. On World Malaria Day (25 April 2016), World Health Organisation (WHO) released a report stating that, although an ambitious prospect, elimination of malaria in at least 35 countries by 2030 is indeed possible. With long-lasting insecticide-treated nets (LLINs), indoor spraying with residual insecticides, antimalarial drugs and rapid diagnostic testing (RDT), mortality rates from malaria have dropped significantly by 60% worldwide since 2000. 
But still, over half a million deaths due to malaria have occurred in 2015. There were an estimated 438,000 malaria deaths in total. Of these deaths, the Sub-Saharan African region has the highest burden of malaria in the world. The number of deaths in Africa accounted for 90%. The main reason for this is due to the African vector species of the Anopheles mosquito having a long lifespan and a strong human-biting habit. The long lifespan of the mosquitoes allows the Plasmodium parasite to develop within the mosquito's body. Children in Africa are especially susceptible to malaria, as compared to the adults who have already developed partial immunity to malaria due to continuous exposure for years. Even as the cases of children under 5 years old in Africa fell by 71% between 2000 - 2015 due to governments and partners taking a more active role in rolling out measures for malaria control, malaria still killed 292,000 children in Africa in 2015.
Over the years, increased investment in research has allowed tools to fight against malaria to be developed. The "Global Fund to Fight AIDS, Tuberculosis and Malaria", "President's Malaria Initiative" by the U.S. and other fundings have allowed these tools to be rolled out to countries to control malaria. The investment in malaria control increased to US$2.5 billion from US$960 million in 2005 - 2014. As reflected by the theme for World Malaria Day 2016 - "End Malaria for Good", WHO and its partners are focused on reducing the rate of malaria cases in at least 35 countries to zero. Continuous measures have to be in place though, to prevent re-establishment of transmission of malaria. Currently, Europe has been eliminated of malaria, reporting zero cases in 2015. This was done through much political support, strong vector control measures and financial help from the Global Fund. However, continuous surveillance and political support will be needed to maintain this achievement. 
More countries are moving towards malaria elimination. In 2015, 33 countries managed to have fewer than 1000 cases of malaria. According to WHO, some of the countries with the potential of eliminating malaria by 2020 include Algeria, South Africa, Mexico, Iran, Saudi Arabia, Nepal, China, Malaysia and South Korea.
The Greater Mekong Subregion (GMS), including countries like Cambodia, Laos, Myanmar, Thailand and Vietnam, has made good progress in lowering annual malaria deaths, with a 60% drop from 1998-2007. Governments and partners have played their part in investing in malaria control measures, showed political support, incorporated malaria controls within national health systems and worked with cross-border countries to control malaria. However, malaria issues still plague this GMS region :
- Resistance to the core ingredient in antimalarial drugs - artemisinin, has been detected in countries in the GMS, especially at the Thailand-Cambodia border. Artemisinin-containing drugs are typically given in combination with partner drugs. And resistance to these partner drugs have been seen as well. Insecticide resistance by the malaria parasite has been noticed also.
- There is rampant use of counterfeit antimalarial drugs, where the quantity of artemisinin is insufficient for proper treatment. Not only is the drug not effective, it further aggravates the problem of drug resistance due to the parasites not being killed off properly. A monitoring network involving the Thai Bureau of Drug and Narcotics and U.S. Pharmacopeia was thus set up in 2002, to control the distribution of counterfeit drugs.
- There is large scale population mobility from high endemic to low endemic areas, especially at the Thailand/China-Myanmar border.
- Ethnic minorities stay in hard to reach areas of the country, where they have little access to basic health services. Furthermore, efforts to bring in malaria control technology or teams to educate these ethnic minorities on malaria, are impeded due to the isolated, hilly, forested nature of these regions. From 2005-2007, Asian Development Bank and WHO started a project to cater to these communities. Volunteers and health personnel within the villages itself were trained in malaria control and provided with the malaria control equipments.
With the pressing issue of drug resistance mentioned in (1), it is good that there are some up and coming new developments in the malaria control scene. One of the notable research advancements is the use of Wolbachia technology in malaria control.Wolbachia infects only male mosquitoes, and prevents females from producing viable progeny after mating. The Wolbachia technology is currently being used to control the spread of dengue. Wolbachia has been found to be able to infect the Anopheles species of mosquito, to help control the incidence of malaria. In a study published by Nature Communications, Flaminia Catteruccia and her colleagues found that the wAnga Wolbachia strain infected 19% - 46% of over 600 Anopheles mosquitoes in Burkina Faso, Africa between 2011-2014. Future studies will have to test if Wolbachia-Plasmodium interactions work in different geographical locations, across different seasons, to determine the overall effectiveness of using Wolbachia as a control strategy.  Another improvement in technology is the development of "next generation anti malarial drugs". Novartis is developing an antimalarial compound KAF156, with the help of Medicines for Malaria Venture and Bill & Melinda Gates Foundation. KAF156 acts on both the blood and liver stages of the malaria parasite's life cycle.  There is currently no existing licensed malaria vaccines. There is however a research vaccine, "RTS, S/AS01", that is in progress of being tested for safety and effectiveness, to be implemented in wider use.
However, the fact remains that many still die from malaria worldwide despite these measures. Surveillance is key to obtain and maintain malaria elimination. Surveillance enables a fast and effective malaria response, tracks progress and holds governments accountable for malaria control. But many countries, especially the under-developed regions, lack the resources like money and infrastructure to put in place these malaria surveillance systems. Some countries do not have the political support of the government, or lack the cooperation of the people. Some countries are nearing elimination, but have remaining cases among migrant populations in hard-to-reach areas within the country.
WHO's Global Technical Strategy for Malaria 2016-2030 suggest 5 core principles countries need to work towards to eliminate malaria:
(a) Tailored responses
(b) Country ownership & leadership
(c) Strengthened surveillance
(d) Equity in access to health services
(e) Innovation in malaria control tools
With these targets, WHO hopes to meet its 2030 goals, including a decrease of 90% of incidence and deaths from malaria globally.  Till a vaccine is approved for worldwide usage, countries must do their part to maintain status quo, even after malaria elimination is achieved.
- WHO 2016 report: Eliminating Malaria
By APBN Writer, Cheryl Lee Zhi Qin
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