Symptoms of Malaria

Stages of Malaria Symptoms also known as "malaria attacks" lasts 6-10 hours and consists of the ff:
1. Cold stage (sensation of cold, shivering)
2. Hot stage (fever, headaches, vomiting; seizures in young children)
3. Sweating stage (sweats, return to normal temperature, tiredness)

More commonly, the patient presents with a combination of the following symptoms:
- Fever
- Chills
- Sweats
- Headache
- Nausea and vomiting
- Body aches
- General malaise

In countries where malaria does not occur very commonly, the symptoms listed may be suspected as symptoms of influenza, cold, and other more common infections. However, people presenting with symptoms in countries where malaria is prevalent, infected individuals undergo "presumptive treatment" without further screening.

Physical findings may include:
- Elevated temperature
- Sweating
- Weakness
- Enlarged Spleen
- Mild Jaundice
- Enlargement of the liver (may be palpated by a professional)
- Increased respiration rate

Diagnostic screening includes blood tests examining for presence of parasites in the blood. Lab levels to check include RBC (usually anemic presentation), platelets (thrombocytopenia - decreased platelet levels), bilirubin (elevated), aminotransferases (elevated).

Severe Malaria: 
Symptoms occur when infections are complicated by serious organ failures or abnormalities in the patient's blood or metabolism. Some of the symptoms include the following:

• Cerebral malaria, with abnormal behavior, impairment of consciousness, seizures, coma, or other neurologic abnormalities

• Severe anemia due to hemolysis (destruction of the red blood cells)

• Hemoglobinuria (hemoglobin in the urine) due to hemolysis

• Acute respiratory distress syndrome (ARDS), an inflammatory reaction in the lungs that inhibits oxygen exchange, which may occur even after the parasite counts have decreased in response to treatment

• Abnormalities in blood coagulation

• Low blood pressure caused by cardiovascular collapse

• Acute kidney failure

• Hyperparasitemia, where more than 5% of the red blood cells are infected by malaria parasites

• Metabolic acidosis (excessive acidity in the blood and tissue fluids), often in association with hypoglycemia

• Hypoglycemia (low blood glucose). Hypoglycemia may also occur in pregnant women with uncomplicated malaria, or after treatment with quinine.

Severe malaria is a medical emergency and should be treated urgently and aggressively.

Malaria Relapse

It is important to note that Malaria could relapse and reoccur in patients even after months or years without showing signs of infection. Relapse occurs due to the parasites that hide and stay dormant in the liver called "dormant liver stage parasites" or "hypnozoites"  that reactivate. Good news is that there are available treatment to prevent relapse. 

Incubation Period

Another important note is that Malaria tends to have an incubation period of 7-30 days in which symptoms do not show after onset of infection or contact with mosquito. Antimalarial drugs that are taken as a preventive measures by travelers can mask and slow down the onset of symptoms. This means that it can take weeks and months before signs and symptoms show. This can result to misdiagnosis or delayed screening by health care provider especially if malaria does not commonly occur at the place of diagnosis. Remember to remind the health care provider of any places traveled to during the last 12 months where malaria occurs frequently. 

The following information are directly from the following site: CDC Malaria Signs and Symptoms

Bibliography:
Disease. (2010, February 8). Retrieved April 30, 2015, from        http://www.cdc.gov/malaria/about/disease.html