Malaria is a mosquito-borne disease caused by a parasite. People with malaria often experience fever, chills, and flu-like illness. Left untreated, they may develop severe complications and die. Each year 350-500 million cases of malaria occur worldwide, and over one million people die, most of them young children in sub-Saharan Africa.
This sometimes fatal disease can be prevented and cured. Bednets, insecticides, and antimalarial drugs are effective tools to fight malaria in areas where it is transmitted. Travelers to a malaria-risk area should avoid mosquito bites and take a preventive antimalarial drug.
In the early symptoms malaria can resemble the onset of flu, periods of chills and fever lasting several hours and occurring every few days. Respite can last from several days to several months. If not treated, the spleen and the liver become enlarged, anemia and jaundice develop. In severe cases delirium and unconsciousness may lead to death from general weakness, anemia, or clogging of the vessels of cerebral tissues by affected red blood cells. Cerebral malaria is mainly encountered in young children and pregnant women.
People with malaria typically have cycles of chills, fever, and sweating that recur every 1, 2, or 3 days. The attack of the malaria parasites on the person’s red blood cells makes the person’s temperature rise and the person feel hot. The subsequent bursting of red blood cells makes the person feel cold and have hard, shaking chills. Nausea, vomiting, and diarrhea often go along with the fever. The destruction of red blood cells can also cause jaundice (yellowing of the skin or whites of the eyes) and anemia.
Common symptoms of malaria are fever, shivering, pain in the joints, headache, vomiting, and anemia. The disease can be diagnosed by a microscopic examination of the patient’s blood and can normally be cured by taking animalarial drugs. However, there are some regions that parasites have developed resistance to these drugs. Over time, humans also develop immunity to the parasite, but children are very vulnerable until they develop this immunity.
The disease is transmitted by mosquitos – they generally are most active in the evening, night and early morning, expecially if there is no wind. So avoid going outside at these times unless you are wear long sleeves and pants to cover exposed skin, use insect repellent and use mosquito nets over doors, windows and beds.
Various medicines help prevent infection but no no antimalarial prophylaxis is totally effective. Some are known to produce some very adverse reactions in certain individuals. Be particularly careful about taking Lariam. You should consult your doctor before taking any anti-malarial drugs.
People living in malarial areas often take no prophylactics and take medicines to cure malaria at the first onset of symptoms. Fansidar is commonly and fairly effectively used to get rid of the disease.
Humans develop malaria when infected with one of the four protazoan parasites from the genus Plasmodium. The four species include:
P. falciparum is the most widespread and dangerous of the four
Transmission of malaria is affected by climate and geography, and often coincides with the rainy season. We become infected with the parasite from anopheline mosquitos. The malaria protazoa develops in the gut of the mosquito and is passed to humans in the saliva of the insect as it draws a person’s blood. The parasite travels to the liver of the human through the blood stream. Here, the Plasmodium multiplies. After 9-16 days, the protazoa return to the blood supply, where they penetrate red blood cells. The parasite then causes red blood cells to break down.
The parasite is spread to people by the female Anopheles mosquito, which feeds on human blood. Although four species of malaria parasites can infect humans and cause illness, only malaria caused by Plasmodium falciparum is potentially life-threatening.
The time between a mosquito bite and the start of illness is usually 7 to 21 days, but some types of malaria parasites take much longer to cause symptoms. When infection occurs by blood transfusion, the time to the start of symptoms depends on the number of parasites in the transfusion.
Where is malaria found?
Malaria transmission occurs in large areas of Central and South America, sub-Saharan Africa, the Indian subcontinent, Southeast Asia, the Middle East, and Oceania. The risk to travelers varies depending on local weather conditions, the number of mosquitoes in the area, and the traveler’s itinerary and time and type of travel.
How is malaria spread?
A person gets malaria from the bite of an infected female mosquito. The mosquito bite injects young forms of the malaria parasite into the person’s blood. The parasites travel through the person’s bloodstream to the liver, where they grow to their next stage of development. In 6 to 9 days, the parasites leave the liver and enter the bloodstream again. They invade the red blood cells, finish growing, and begin to multiply quickly. The number of parasites increases until the red blood cells burst, releasing thousands of parasites into the person’s bloodstream. The parasites attack other red blood cells, and the cycle of infection continues, causing the common signs and symptoms of malaria.
When a non-infected mosquito bites an infected person, the mosquito sucks up parasites from the person’s blood. The mosquito is then infected with the malaria parasites. The parasites go through several stages of growth in the mosquito. When the mosquito bites someone else, that person will become infected with malaria parasites, and the cycle will begin again.
Malaria parasites can also be transmitted by transfusion of blood from an infected person or by the use of needles or syringes contaminated with the blood of an infected person.
How is malaria diagnosed?
Malaria is diagnosed by a blood test to check for parasites.
Who is at risk for malaria?
Anyone who lives in or travels to a country where there are malaria-infected people and mosquitoes is at risk.
What complications can result from malaria?
Malaria caused by Plasmodium falciparum can cause kidney or liver failure, coma, and death. Although infections with other malaria parasites cause less serious illness, parasites can remain inactive in the liver and cause a reappearance of symptoms months or even years later.
Is malaria an emerging infectious disease?
Yes. Many countries have been experiencing a resurgence in cases caused by Plasmodium falciparum, the most deadly of the four human malaria parasites. Urban migration, poverty, and poor sanitation have returned malaria to cities where it once was eliminated. New roads, logging, and irrigation have drawn people into once-isolated areas where mosquitoes thrive. Refugees, migrants, and tourists have spread the disease across borders.
The seriousness of the worldwide re-emergence of malaria is made worse by the spread of parasites that are resistant to anti-malaria drugs. Parasites, like bacteria and viruses, can develop resistance to the drugs used to prevent or treat infection. Malaria parasites are increasingly resistant to chloroquine, the drug most widely used for prevention and treatment. Chloroquine-resistant strains have been reported from areas in Africa, Asia, and the Americas.
The potential also exists for malaria to become re-established in the United States. Currently, about 1,200 malaria cases are reported each year in the United States. Almost all occur in persons who were infected in other parts of the world (imported malaria). Small outbreaks of non-imported malaria, the result of transmission from imported cases, have also been reported. So far, the outbreaks have been quickly and easily contained. A continued increase in drug-resistant malaria throughout the world, however, could increase the number of cases of imported malaria and improve the chances for malaria to re-emerge in the United States.
How can malaria be prevented?
No vaccine against malaria is available. Travelers can protect themselves by using anti-mosquito measures and by taking drugs to prevent malaria.
1. Avoid mosquito bites — Avoiding the bites of Anopheles mosquitoes is the best way to prevent infection. Because Anopheles mosquitoes feed at night, malaria transmission happens mainly between dusk and dawn. Travelers should take steps to reduce contact with mosquitoes both when outdoors and inside, especially during these hours.
When outside: Wear long-sleeved clothing and long pants. For extra protection, treat clothing with the insecticide permethrin.
Use insect repellent on exposed skin. The most effective repellents contain 20% to 35% DEET (N,N-diethylmethyltoluamide). Follow application instructions carefully when using these products.
When inside: Stay in well-screened areas as much as possible during the evening.
Spray living and sleeping areas with insecticide.
Use a bednet when sleeping in a room that is not screened or air conditioned. For extra protection, treat the bednet with the insecticide permethrin.
2. Take anti-malaria drugs — When traveling to an area known to have malaria, discuss your travel plans with a doctor well before departure. Medicines to prevent malaria are usually prescribed for persons traveling to areas where malaria is common. Travelers from different countries might receive different recommendations because of differences in the availability of medicines. Travelers visiting only cities or rural areas where there is no risk of malaria might not need preventive drugs. An exact itinerary is needed to decide on the right degree of protection.
To be sure that your anti-malaria drug helps protect you against malaria, you must follow the recommended doses and schedules exactly:
Take pills on the same day each week, or, for pills to be taken daily, at the same time each day.
Take pills after meals.
Take the recommended doses 1 to 2 weeks before travel, throughout the trip, and for 4 weeks after leaving the area with malaria.
Do not stop taking the pills after arriving home. Complete the full dosage.
Travelers should understand that they can get malaria even if they use anti-malaria drugs. Pregnant women and young children need special instructions because of the potential effects of malaria illness and the danger in using some drugs for malaria prevention and treatment.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.