Malaria (patient information)
|
Malaria |
|
Malaria On the Web |
|---|
For the WikiDoc page for this topic, click here
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Priyamvada Singh, MBBS [2]
Overview
Malaria is a parasitic disease that involves high fevers, shaking chills, flu-like symptoms, and anemia.
What are the symptoms of Malaria?
Common symptoms of malaria may include:
The classic progression of the disease which however, is rarely observed, is as follows:
- Cold stage - whee the patients experiences a sensation of cold and shivering
- Hot stage - characterized by fever, headaches, and children may experience seizures
- Sweating stage - characterized by sweats and return to normal temperature with a feeling of tiredness
Following the infective bite by the Anopheles mosquito, a period of time (the "incubation period") goes by before the first symptoms appear. The incubation period in most cases varies from 7 to 30 days.
What causes Malaria?
Malaria is caused by a parasite that commonly infects a certain type of mosquito which feeds on humans. The disease may be transmitted from one human to another by the bite of infected Anopheles mosquitoes.
Four kinds of malaria parasites have long been known to infect humans:
- Plasmodium falciparum
- P. vivax
- P. ovale
- P. malariae.
- P. knowlesi - a recently recognized type of malaria that naturally infects macaques in Southeast Asia, that also infects humans, causing malaria that is transmitted from animal to human ("zoonotic" malaria).
Falciparum malaria, one of four different types of malaria, affects a greater proportion of the red blood cells than the other types and is much more serious. It can be fatal within a few hours of the first symptoms.
Malaria can also be transmitted from a mother to her unborn baby (congenitally) and by blood transfusions.
Malaria can be carried by mosquitoes in temperate climates, but the parasite disappears over the winter.
In some areas of the world, mosquitoes that carry malaria have developed resistance to insecticides. In addition, the parasites have developed resistance to some antibiotics. This has led to difficulty in controlling both the rate of infection and spread of this disease.
Who is at highest risk?
- Anyone is at risk to get malaria.
- Most cases occur in people who live in countries where malaria is endemic.
- People who live in countries where malaria is not endemic, may also get the disease when they travel to such countries, or through blood transfusions.
- Malaria may also be transmitted from an infected mother to her infant before or during delivery.
Who is at Highest Risk of Dying from Malaria?
- People who are heavily exposed to the bites of mosquitoes infected with P. falciparum (causes severe and life-threatening malaria) are most at risk of dying from malaria.
- People who live in countries in Africa south of the Sahara desert, where P. falciparum is very common
- People who have little or no immunity to malaria, such as young children and pregnant women or travelers coming from areas with no malaria
- Poor people living in rural areas who lack access to health care
When to seek urgent medical care?
Urgent medical care should be sought when:
- Symptoms of malaria occur, during a travel to a country where malaria is endemic
- Travelers who become ill with a fever or flu-like illness either while traveling in a malaria-risk area, or after returning home (for up to 1 year). It is important to always report the travel history to the health-care provider
Diagnosis
Health-care providers should always obtain a travel history from febrile patients. Fever in a person who has recently traveled in a malaria-endemic area should always be immediately evaluated using the appropriate diagnostic tests for malaria.
Clinical diagnosis is based on the patient's symptoms and on physical findings at examination. The first symptoms of malaria are often not specific and are also found in other diseases (such as the "flu" and common viral infections). Likewise, the physical findings are often not specific.
In severe malaria, clinical findings are more striking and may increase the index of suspicion for malaria. These may include:
- Confusion
- Coma
- Neurologic focal signs
- Severe anemia
- Respiratory difficulties
Clinical findings should always be confirmed by a laboratory test for malaria. Diagnostic tests may include:
- Microscopic diagnosis
- Antigen detection
- Molecular diagnosis
- Serology
- Drug resistance tests
In addition to ordering the malaria specific diagnostic tests described below, the health-care provider should conduct an initial workup and request:
- Complete blood count
- Routine chemistry panel
In the event that the person does have a positive malaria test, these additional tests will be useful in determining whether the patient has uncomplicated or severe manifestations of the malaria infection. Specifically, these tests can detect:
- Severe anemia
- Hypoglycemia
- Renal failure
- Hyperbilirubinemia
- Acid-base disturbances
Treatment options
Malaria can be a severe, potentially fatal disease (especially when caused by Plasmodium falciparum) and treatment should be initiated as soon as possible.
Treatment of malaria depends on many factors including:
- Disease severity
- Species of malaria parasite causing the infection
- Part of the world in which the infection was acquired
These latter 2 characteristics help determine the probability that the organism is resistant to certain antimalarial drugs. Patients who have severe P. falciparum malaria or who cannot take oral medications should be given the treatment by continuous intravenous infusion.
Most drugs used in treatment are active against the parasite forms in the blood (the form that causes disease) and include:
- Chloroquine
- atovaquone-proguanil
- Artemether-lumefantrine
- Mefloquine
- Quinine
- Quinidine
- Doxycycline (used in combination with quinine)
- Clindamycin (used in combination with quinine)
The choice of medication may depend on the location of the patients when he/she was infected. Aggressive supportive medical care, including intravenous (IV) fluids and other medications and breathing (respiratory) support may be needed.
Where to find medical care for Malaria?
Directions to Hospitals Treating Malaria
Prevention
- Most people living in areas where malaria is common have acquired some immunity to the disease.
- Visitors will not have immunity, and should take preventive medications. It is important to see your health care provider well before your trip, because treatment may begin as long as 2 weeks before travel to the area, and continue for a month after you leave the area.
- The types of anti-malarial medications prescribed will depend on the area you visit. According to the CDC, travelers to South America, Africa, the Indian subcontinent, Asia, and the South Pacific should take one of the following drugs:
- Mefloquine
- Doxycycline
- Choroquine
- Hydroxychoroquine
- Malarone
- Pregnant women should take preventive medications, because the risk of side-effects from the treatment to the fetus is less than the risk of acquiring a congenital infection.
- People on anti-malarial medications may still become infected. Avoid mosquito bites by wearing protective clothing over the arms and legs, using screens on windows, and using insect repellent.
- Chloroquine has been the drug of choice for protection from malaria. But because of resistance, it is now only suggested for use in areas where Plasmodium vivax, P. oval, and P. malariae are present. Falciparum malaria is becoming increasingly resistant to anti-malarial medications.
- For travelers going to areas where Falciparum malaria is known to occur, there are several options for malaria prevention, including:
- Mefloquine
- Atovaquone/Proguanil (Malarone)
- Doxycycline.
Travelers can call the CDC for information on types of malaria in a given geographical area, preventive drugs, and times of the year to avoid travel.
What to expect (Outlook/Prognosis)?
The outcome is expected to be good in most cases of malaria with treatment, but poor in Falciparum infection with complications.
Possible complications
Possible complications:
- Destruction of blood cells (hemolytic anemia)
- Liver failure and kidney failure
- Meningitis
- Respiratory failure from fluid in the lungs (pulmonary edema)
- Rupture of the spleen leading to massive internal bleeding (hemorrhage)
Alternative Names
Quartan malaria; Falciparum malaria; Biduoterian fever; Blackwater fever; Tertian malaria; Plasmodium
Sources
http://www.nlm.nih.gov/medlineplus/ency/article/000621.htm Template:WSTemplate:WH