<p>Malaria is a serious global concern with over three billion people at risk in 95 countries and around 4,00,000 deaths every year. Developing solutions to combat the disease has proven difficult due to various resistances from both parasites and mosquitoes.</p>.<p><strong>What causes malaria?</strong></p>.<p>Malaria is an infectious disease that can be transmitted to humans by a mosquito bite. The Anopheles species is the only type of mosquito capable of spreading this dangerous parasite, as it becomes infected when biting someone who already has malaria in their bloodstream and then transmits it through its next bite victim. To prevent yourself from becoming ill with malaria, make sure to take protective measures when outside during times when mosquitoes are active. Five species of Plasmodium (single-celled parasites) can infect humans and cause illness: Plasmodium falciparum (or P. falciparum); Plasmodium malariae (or P. malariae); Plasmodium vivax (or P. vivax); Plasmodium ovale (or P. ovale); Plasmodium knowlesi (or P. knowlesi).</p>.<p>Falciparum malaria can be deadly, with patients potentially facing liver and kidney failure, convulsions, or even slipping into a coma. Other types of malaria such as P. vivax and P. ovale may not have life-threatening effects initially but the parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later.</p>.<p>The emergence and spread of antimalarial drug resistance is a cause for global concern, as it has the potential to undermine years of malaria control efforts. Unfortunately, two out of four parasites that cause human malaria have already developed some level of immunity — Plasmodium falciparum and P. vivax. It is unknown if P. malariae or P. ovale has developed resistance to any of the antimalarials.</p>.<p><strong>How malaria parasites<br />develop resistance?</strong></p>.<p>Resistance to antimalarial drugs arises because of the selection of parasites with genetic mutations or gene amplifications that confer reduced susceptibility. Resistance appears to be caused by a change in the structure, function, or quantity. P. falciparum, the most dangerous type of malaria-causing parasite, has developed a troubling resistance to numerous antimalarial drugs available today such as sulfadoxine/pyrimethamine, mefloquine and quinines. Although resistance to these drugs tends to be much less widespread geographically, in some areas of the world, the impact of multi-drug-resistant malaria can be extensive.</p>.<p>Most recently, resistance to the artemisinin and non-artemisinin components of artemisinin-based combination therapy has emerged in parts of Southeast Asia, impacting the efficacy of this vital antimalarial class. Symptoms may come and go in cycles. Malaria may also cause more serious problems. These include damage to the heart, lungs, kidneys, or brain. It can even be deadly. But you can do a lot to prevent this infection.</p>.<p><strong>Which malaria is most drug-resistant?</strong></p>.<p>In the 1950s and 60s, chloroquine resistance to malaria began popping up around Southeast Asia, Oceania and South America. Fast forward decades later and this resistant strain has spread across most of the world where falciparum-caused malaria is transmitted.</p>.<p>What is the best treatment option for malaria in areas of drug resistance?</p>.<p>Artemisinin-based combination therapies (ACTs) are a combination of two or more drugs that work against the malaria parasite in different ways. This is usually the preferred treatment for chloroquine-resistant malaria. Examples include artemether-lumefantrine (Coartem) and artesunate-mefloquine.</p>.<p><strong>Protection from mosquitoes</strong></p>.<p>♦ Be aware that you are still at risk for malaria even with the use of protection.<br />♦ To avoid mosquito bites, apply insect repellent to exposed skin. The recommended repellent contains 20-35% percent N,N-Diethyl-meta-toluamide (DEET).<br />♦ Wear long-sleeved clothing and full-length bottom wear if you are outdoors at night. <br />♦ Use a mosquito net over the bed if your bedroom is not air-conditioned or screened. For additional protection, treat the mosquito net with the insecticide permethrin.<br />♦ Spray an insecticide or repellent on clothing as mosquitoes may bite through thin clothing. <br />♦ Spray pyrethrin or a similar insecticide in your bedroom before going to bed.</p>.<p><em><span>(The author is a senior consultant in internal medicine.)</span></em></p>
<p>Malaria is a serious global concern with over three billion people at risk in 95 countries and around 4,00,000 deaths every year. Developing solutions to combat the disease has proven difficult due to various resistances from both parasites and mosquitoes.</p>.<p><strong>What causes malaria?</strong></p>.<p>Malaria is an infectious disease that can be transmitted to humans by a mosquito bite. The Anopheles species is the only type of mosquito capable of spreading this dangerous parasite, as it becomes infected when biting someone who already has malaria in their bloodstream and then transmits it through its next bite victim. To prevent yourself from becoming ill with malaria, make sure to take protective measures when outside during times when mosquitoes are active. Five species of Plasmodium (single-celled parasites) can infect humans and cause illness: Plasmodium falciparum (or P. falciparum); Plasmodium malariae (or P. malariae); Plasmodium vivax (or P. vivax); Plasmodium ovale (or P. ovale); Plasmodium knowlesi (or P. knowlesi).</p>.<p>Falciparum malaria can be deadly, with patients potentially facing liver and kidney failure, convulsions, or even slipping into a coma. Other types of malaria such as P. vivax and P. ovale may not have life-threatening effects initially but the parasites can remain dormant in the liver for many months, causing a reappearance of symptoms months or even years later.</p>.<p>The emergence and spread of antimalarial drug resistance is a cause for global concern, as it has the potential to undermine years of malaria control efforts. Unfortunately, two out of four parasites that cause human malaria have already developed some level of immunity — Plasmodium falciparum and P. vivax. It is unknown if P. malariae or P. ovale has developed resistance to any of the antimalarials.</p>.<p><strong>How malaria parasites<br />develop resistance?</strong></p>.<p>Resistance to antimalarial drugs arises because of the selection of parasites with genetic mutations or gene amplifications that confer reduced susceptibility. Resistance appears to be caused by a change in the structure, function, or quantity. P. falciparum, the most dangerous type of malaria-causing parasite, has developed a troubling resistance to numerous antimalarial drugs available today such as sulfadoxine/pyrimethamine, mefloquine and quinines. Although resistance to these drugs tends to be much less widespread geographically, in some areas of the world, the impact of multi-drug-resistant malaria can be extensive.</p>.<p>Most recently, resistance to the artemisinin and non-artemisinin components of artemisinin-based combination therapy has emerged in parts of Southeast Asia, impacting the efficacy of this vital antimalarial class. Symptoms may come and go in cycles. Malaria may also cause more serious problems. These include damage to the heart, lungs, kidneys, or brain. It can even be deadly. But you can do a lot to prevent this infection.</p>.<p><strong>Which malaria is most drug-resistant?</strong></p>.<p>In the 1950s and 60s, chloroquine resistance to malaria began popping up around Southeast Asia, Oceania and South America. Fast forward decades later and this resistant strain has spread across most of the world where falciparum-caused malaria is transmitted.</p>.<p>What is the best treatment option for malaria in areas of drug resistance?</p>.<p>Artemisinin-based combination therapies (ACTs) are a combination of two or more drugs that work against the malaria parasite in different ways. This is usually the preferred treatment for chloroquine-resistant malaria. Examples include artemether-lumefantrine (Coartem) and artesunate-mefloquine.</p>.<p><strong>Protection from mosquitoes</strong></p>.<p>♦ Be aware that you are still at risk for malaria even with the use of protection.<br />♦ To avoid mosquito bites, apply insect repellent to exposed skin. The recommended repellent contains 20-35% percent N,N-Diethyl-meta-toluamide (DEET).<br />♦ Wear long-sleeved clothing and full-length bottom wear if you are outdoors at night. <br />♦ Use a mosquito net over the bed if your bedroom is not air-conditioned or screened. For additional protection, treat the mosquito net with the insecticide permethrin.<br />♦ Spray an insecticide or repellent on clothing as mosquitoes may bite through thin clothing. <br />♦ Spray pyrethrin or a similar insecticide in your bedroom before going to bed.</p>.<p><em><span>(The author is a senior consultant in internal medicine.)</span></em></p>