Malaria

Select the topic

• What causes malaria?
• Malaria symptoms
• How is malaria diagnosed?
• How is malaria treated?
• Malaria prevention
• Is malaria curable?

Malaria

Malaria is a disease caused by protozoa infection, a parasite in the plasmodium genus spread by female Anopheles mosquitoes, a carrier of the malaria parasite to humans when entering the forest in an endemic area. If bitten by infected mosquitoes, humans will develop high fever, chills, headaches, and muscle aches. Malaria can lead to intravascular hemolysis, jaundice, or kidney failure. Cerebral malaria can lead to convulsions, various internal organ failures, and death.

What causes malaria?

Malaria spreads by the mosquito vector -- female Anopheles mosquitoes—a daytime feeding insect from dusk to early morning—biting and spreading the infection among humans. The malaria life cycle begins with anopheles mosquitoes biting and sucking the blood of a malaria-infected person at the gametocyte stage, where the parasites disseminate in the mosquito; the male and female forms of gametocytes mate in the gut, where they live for about 10–12 days, develops into sporozoites and travels to mosquito salivary glands. At this stage, if a malaria-infected mosquito bites a person, the parasites in the saliva will spread into the bloodstream, go to, and incubate in the liver for 10–14 days before invading the red blood cells with manifested symptoms of high fever and chills. In some cases, malaria may not cause acute symptoms in some people, particularly those who live in endemic areas, such as the border areas of Thailand, Myanmar, Cambodia, etc.

How many types of malaria?

There are five species of parasites that cause malaria in humans, including:

1. Plasmodium falciparum is the most severe form of malaria that can lead to cerebral malaria and death. The incubation period for this species is 7-14 days.
2. Plasmodium vivax is a less severe type of malaria, but it can cause severe symptoms if left untreated. The parasite remains dormant in the liver for many years until malaria recurs. This type of species has an incubation period of 8–14 days.
3. Plasmodium malaria is a type of malaria parasite that can cause chronic infection. The incubation period after infection is approximately 18-40 days.
4. Plasmodium ovale is a type of malaria parasite that can remain latent in the liver for many years after infection.
5. Plasmodium knowlesi is a type of malaria parasite that rapidly progresses and remains dormant for many years. This parasite species is found in macaques and is transmitted to humans by the Anopheles mosquito that carries the disease.

What are the symptoms of malaria?

A person bitten by an infected Anopheles mosquito becomes symptomatic within 10–14 days to several weeks, beginning with flu-like symptoms without a runny nose, followed by fever, chills, sweating, headache, body and muscle aches, nausea, vomiting, and loss of appetite. Symptoms range from mild to severe, depending on the malaria strain and individual body immunity. Some can remain dormant in the liver for years before spreading into the bloodstream, infecting, and destroying red blood cells, and precipitating malaria symptoms. There are three malaria stages as follows:

1. Cold stage malaria, or the first stage of malaria: This stage lasts approximately 15-60 minutes, during which time the parasites invade the red blood cells and destroy them, resulting in fever, shivering with goosebumps, trembling, tooth clenching, coughing, shortness of breath, high blood pressure, rapid pulse, a cold body, nausea, vomiting, and frequent urination. The body temperature gradually rises to the hot stage.
2. Hot Stage Malaria: Approximately 2 hours after the first stage, symptoms include a high fever, a hot body, hot breath, a pale mouth, thirst, a rapid pulse, high blood pressure, a red face, red skin, dry skin, eye socket pain, nausea, vomiting, diarrhea, a severe headache, and restlessness before entering the Sweating stage. Young children may experience convulsions.
3. Sweating stage malaria: The symptoms appear approximately 1 hour after the second stage. The fever begins to subside, followed by sweating, starting in the temples, then throughout the body. The body temperature rapidly drops, and the blood pressure will return to normal, followed by extreme tiredness and falling asleep. If untreated, malaria relapses at the Cold stage and re-enacts through the two succeeding stages, according to the malaria life cycle.

How is malaria diagnosed?

The doctor will diagnose malaria by obtaining a history of being bitten by an anopheles mosquito, including a history of traveling to endemic areas or camping near a creek or in a mountainous forest; conduct an initial physical examination to assess symptoms and differentiate malaria from other diseases having similar symptoms, such as the common cold, dengue, chikungunya, or Zika. The doctor will diagnose malaria using the following methods:

• A thick and Thin Blood Smear is a test that detects blood infection by taking blood samples for microscopic examination in the laboratory using blood staining techniques or smearing blood with Wright-Giemsa stain on a thick and thin blood film. It is a sensitive and specific malaria test, providing fast and accurate results while identifying the strains of parasite-causing malaria, counting their density, and identifying malaria stages.
• Complete blood count (CBC) to look for markers of protozoa infection in the blood and to measure the concentration of red blood cells, white blood cells, and platelets.
• A gene test is a DNA-based test that looks for abnormalities or changes in genes to detect markers of malaria infection and identify the type of malaria for which other testing methods yield negative results.
• Antibodies test detects specific antibodies produced in response to infection with the plasmodium protozoa.
• Biological examination (PCR) is a test that detects malaria genetic material in the body and determines the strain of the malaria parasite. The test is appropriate when other tests produce negative results.
• Rapid diagnostic tests (RDTs) can detect malaria when microscopic examination is not accessible, such as in remote areas. It is an easy-to-use test kit that yields quick results. However, the results may not be as accurate as sending the sample to a lab and may not detect all types of malaria.

How is malaria treated?

As soon as malaria infection is confirmed, doctors will prescribe antimalaria drugs to kill and eliminate malaria parasites as rapidly as possible, allowing the infected person to return to a relatively normal state while preventing malaria complications. Before prescribing medication, the doctor will determine the type of malaria, the severity of the symptoms, and the patient's age, including pregnancy status.

Antimalaria medications include the following:

• Chloroquine is an antibiotic that only kills some strains of the malaria parasite. However, some malaria species may be resistant to it.
• Artemisinin is the most effective antimalarial drug, effective against all types of malaria, including those resistant to other antimalarials. For the best possible treatment outcome, the doctor will prescribe artemisinin in combination with two or more other drugs (Artemisinin-base combination therapies, or ACTs), such as Coartem, an antimalarial combination of Artemether and lumefantrine, or Artesunate and mefloquine.
• Malarone is an antimalarial combination of atovaquone and proguanil.
• Quinine sulfate in combination with doxycycline
• Primaquine phosphate

What are the complications of malaria?

Severe malaria can lead to life-threatening complications and necessitates immediate treatment. Complications of malaria include:

• Cerebral malaria is caused by protozoa parasites in red blood cells blocking the small blood vessels carrying oxygen to the brain, causing swelling or damage to the brain, as well as seizures and death.
• Pulmonary edema occurs when fluid accumulates in the lungs, causing difficulty breathing.
• Malaria-induced organ failure damages the liver and kidneys and can result in spleen rupture, shock, and death.
• Anemia is caused by malaria destroying red blood cells, resulting in a lack of tissue oxygen.
• Low blood sugar levels, Severe malaria can cause low blood sugar levels, or hypoglycemia, which can lead to critical conditions and death.
• Premature birth: Malaria in pregnant women can result in premature birth, low birth weight, and fetal death.

What are the preventions for malaria?

• To avoid mosquito bites, use a mosquito repellent containing DEET, apply mosquito repellent, dress in long-sleeved shirts, long pants, socks, and mosquito repellent-coated clothing.
• Sleep in mosquito nets to keep mosquitoes away; hang a mosquito net on the door and close the windows to keep mosquitoes out.
• Remove the larvae source and any stagnant water sources around the house or community. Cover water containers and bins with lids.
• Those planning on trekking, overnight camping in the forest, or traveling to malaria-infested areas should consult a doctor a few months before the trips.

How long does malaria last?

Malaria can be cured in 2 weeks if diagnosed early and treated properly, but without proper treatment, those infected with malaria may recur periodically with symptoms of fever, chills.

Malaria—A curable mosquito threat

Malaria is a mosquito-borne disease that can cause organ damage and death. Those bitten by Anopheles mosquitoes, including those returning from hiking or camping in the forest and those returning from outbreak areas with initial signs and symptoms of malaria, should seek medical attention from a specialist doctor for detailed diagnostic examinations. Those planning to travel to outbreak areas should consult their doctor, in advance, for preventative measures. Early malaria treatment is often more effective than late treatment in severe stages or for complications and can help prevent malaria from spreading to others.

FAQ

• Is malaria curable?
  Malaria is curable with medications against the specific type of malaria and should be taken continuously under the supervision of a doctor. Early drug discontinuation can result in drug resistance, incurable diseases, and complications.