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.Malaria is one of the most common infectious diseases and an enormous public health problem.
Five species of the plasmodium parasite can infect humans; the most serious forms of the disease are caused by ”Plasmodium falciparum”. Malaria caused by ”Plasmodium vivax”, ”Plasmodium ovale” and ”Plasmodium malariae” causes milder disease in humans that is not generally fatal. A fifth species, ”Plasmodium knowlesi”, causes malaria in macaques but can also infect humans. This group of human-pathogenic ”Plasmodium” species is usually referred to as ”malaria parasites”.
Types of Malaria:
1. Plasmodium vivax (P. vivax) – milder form of the disease, generally not fatal. However, infected people still need treatment because their untreated progress can also cause a host of health problems. This type has the widest geographic distribution globally. About 60% of infections in India are due to P. vivax. This parasite has a liver stage and can remain in the body for years without causing sickness. If the patient is not treated, the liver stage may re-activate and cause relapses – malaria attacks – after months, or even years without symptoms.
2. Plasmodium malariae (P. malariae) – milder form of the disease, generally not fatal. However, the infected human still needs treatment because no treatment can also lead to a host of health problems. This type of parasite has been known to stay in the blood of some people for several decades.
3. Plasmodium ovale (P. ovale) – milder form of the disease, generally not fatal. However, the infected human still needs to be treated because it may progress and cause a host of health problems. This parasite has a liver stage and can remain in the body for years without causing sickness. If the patient is not treated, the liver stage may re-activate and cause relapses – malaria attacks – after months, or even years without symptoms.
4. Plasmodium falciparum (P. faliparum) – the most serious form of the disease. It is most common in Africa, especially sub-Saharan Africa. Current data indicates that cases are now being reported in areas of the world where this type was thought to have been eradicated.
5. Plasmodium knowlesi (P. knowlesi) – causes malaria in macaques but can also infect humans.
Causes And Risk Factors of Malaria:
The incubation period for malaria varies considerably. An incubation period is the time between the mosquito bite and the time symptoms of malaria begin to appear. The incubation period differs depending on the kind of parasite involved. There are following causes of Malaria:
- Female mosquitoes that carry the plasmodium parasite in their bodies transmit malaria.
- Rainfall is the leading cause of malaria epidemics as it creates high mosquito population.
- If the mosquito bites infected person then bites uninfected person then it may transfer those parasites to the uninfected person.
- It can also be transmitted through blood transfusions.
The biggest risk factor for developing malaria is to live in or to visit tropical areas where the disease is common. Many different subtypes of malaria parasites exist. The variety that causes the most lethal complications is most commonly found in:
- African countries south of the Sahara desert
- The Indian subcontinent
- Solomon islands, Papua New Guinea and Haiti
Risks of more severe disease:
People at increased risk of serious disease include:
- Young children and infants
- Travelers coming from areas with no malaria
- Pregnant women and their unborn children
Poverty, lack of knowledge, and little or no access to health care also contribute to malaria deaths worldwide.
Signs And Symptoms:
Early symptoms of malaria can include irritability and drowsiness, with poor appetite and trouble sleeping. These symptoms are usually followed by chills, then a fever with rapid breathing. The fever may either gradually increase over 1 to 2 days or may rise very suddenly to 105° F (40.6° C) or above. Then, as fever ends and body temperature quickly returns to normal, there’s an intense episode of sweating.
The symptoms characteristic of malaria include flu like illness with fever, chills, muscle aches, and headache. Some patients develop nausea, vomiting, cough, and diarrhea. Cycles of chills, fever, and sweating that repeat every one, two, or three days are typical. There can sometimes be vomiting, diarrhea, coughing, and yellowing (jaundice) of the skin and whites of the eyes due to destruction of red blood cells and liver cells.
Other common symptoms may include:
- Dry cough
- Back pain
- Muscle ache
- Enlarged spleen
Because the initial symptoms are not specific and can be mistaken for other diseases, it can be difficult to diagnose. In countries where the disease is seen a lot, it’s not uncommon for doctors to treat people for malaria who have fever of no obvious cause without getting laboratory confirmation.
Signs And Tests:
During a physical examination, the doctor may find an enlarged liver or enlarged spleen. Malaria blood smears taken at 6 to 12 hour intervals confirm the diagnosis.
A complete blood count (CBC) will identify anemia if it is present.
Diagnosis of Malaria:
Malaria can be diagnosed with a blood test. Blood tests sometimes need to be repeated after a seventy-two-hour period to confirm the diagnosis.
Complications:
- Brain infection (cerebritis)
- Destruction of blood cells (hemolytic anemia)
- Kidney failure
- Liver failure
- Meningitis
- Respiratory failure from fluid in the lungs (pulmonary edema)
- Rupture of the spleen leading to massive internal bleeding (hemorrhage)
Treatments of Malaria:
Treatment of Malaria depends on the following factors:
- Type of infection.
- Severity of infection.
- Status of the host.
- Associated conditions/ diseases.
Treatment Includes:
- Anti-malarial drugs can be prescribed to people traveling to areas where malaria is prevalent. Malaria can be treated with drugs. However, treatment is complicated because each type of malaria requires a different drug.
- Quinine is an effective in treating some forms of malaria, but other parasites have developed a resistance to quinine.
- If quinine is not effective, then a modified form of quinine known as chloroquine can also be used.
- Patients with very serious cases of malaria may require hospitalization and special treatments. Call your health care provider if you develop fever and headache after visiting the tropics.
Medications:
The most common antimalarial drugs include:
- Chloroquine (Aralen)
- Quinine sulfate (Qualaquin)
- Hydroxychloroquine (Plaquenil)
- Mefloquine
- Combination of atovaquone and proguanil (Malarone)
The history of antimalarial medicine has been marked by a constant struggle between evolving drug-resistant parasites and the search for new drug formulations. In many parts of the world, for instance, resistance to chloroquine has rendered the drug ineffective.