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

Malaria - DiagnosticTesting

        Malaria should be considered an emergency as it can be fatal if not treated appropriately in a timely manner. An individual may be suffering from severe malaria symptoms (e.g. confusion, coma, neurologic focal signs, severe anemia, and respiratory complications) or from first symptoms of malaria that are hard to distinguish from the usual presentation of flu and other viral infections. In places where malaria is not prevalent such as in the US, healthcare providers should be aware that they must test for malaria infection in patients who are experiencing symptoms listed. 

The first symptoms of malaria include the ff:
- fever
- chills
- sweats
- headaches
- muscle pains
- nausea and vomiting

        It may be challenging to detect malaria due to its common clinical presentation during its early stages. In order to rule out malaria, one needs to be examined for laboratory tests that would indicate whether one's RBC (i.e. red blood cell) is infected with malaria parasites. It should also include complete blood count workup initially and chemistry panel routinely.
What we mainly look at are the occurrences of the ff: 

- presence of malaria parasites in the blood

- presence of antigen from malaria parasites 

- presence of antibodies made by the body to fight off malaria infection

- severe anemia (i.e. low red blood cell count)

- hypoglycemia (i.e. low blood sugar levels)

- renal failure

- hyperbilirubinemia (i.e. high bilirubin levels in the blood related to the destruction of RBCs releasing hemoglobin that is further broken down into bilirubin)

- acid-base disturbances

        The WHO recommends to perform diagnostic tests first before treatment of any kind.

TEST. TREAT. TRACK approach to malaria treatment. 

        The two main ways to test for malaria include rapid diagnostic test (RDT) and microscopy. 

RDTs - tests for antigens produced by malaria parasites that are present in infected people. It is used because of convenience and due to less complicated way of performing and interpreting the test. RDT generally provides more rapid results that are useful in communities in which microscopy test services are not available. 

Microscopy - a way to test for malaria parasites by microscopically looking at blood smears. It allows identification and for us to determine which type of malaria parasites (e.g. P. falciparum, P. vivax, P. malariae, and P. ovale) is present in the bloodstream. This type of test is most common in hospitals and clinics. To ensure effective and specific microscopy test, there are a set of requirements to ensure quality management. Visit these sites to learn more: Quality assurance of microscopy-based diagnosis and CDC: Malaria - Diagnostic Testing.

Interesting watch about an innovative way to diagnose Malaria without pricking by Joshia Kavuma.

If you already know the background of malaria, listen about Joshia Kavuma's proposal in the video, click on 5:36. 

Bibliography:
Malaria Diagnosis (United States). (2012, November 9). Retrieved April 22, 2015, from http://www.cdc.gov/malaria/diagnosis_treatment/diagnosis.html

Rapid diagnostic tests. (2014, March 25). Retrieved April 22, 2015, from http://www.who.int/malaria/areas/diagnosis/rapid_diagnostic_tests/en/

How Malaria Infects the Body

        Malaria parasites infect two hosts namely, humans and female Anopheles mosquitoes. Let us first talk about the life cycle of malaria parasites in human body. First, the parasites grow and multiply in the liver cells and then infect red blood cells (RBC). After infecting red blood cells, they grow and multiply and later destroy them. The death of these RBCs cause the release of malaria parasites in neighboring RBCs. And the cycle goes on and on causing symptoms of malaria to manifest from mild to severe. 

        You may be wondering how the Anopheles mosquitoes come into play in the transmission of malaria parasites. Remember that after infecting liver cells, these parasites attack RBCs of our body. A form of food for mosquitoes is human blood (our RBCs) and if a person's RBBs are infected with malaria parasites, they ingest and get infected themselves. Mosquitoes do not suffer from the presence of malaria parasites unlike humans who manifest symptoms as their liver cells and RBCs are infected. Hence, these mosquitoes are able to survive and act as vectors (i.e. carriers of the disease and mode of transmission of these parasites from one human to another).  After 10-18 days, the parasites are found in the mosquitoes salivary glands and transmits the malaria parasites to the next human they will take a blood meal on. 

Click here for Malaria Life Cycle animation via Youtube: 

        After learning a little bit about the pathophysiology (i.e. how the disease works on the body), you may have some guesses as to what symptoms present in a person infected by malaria parasites.  

Early Symptoms include:

- Fever (usual symptom at an event of infection)

- Headache

- Chills

- Vomiting.

          If early symptoms are not treated within 24 hours which is possible because its early symptoms are not unique presentations to malaria exclusively, it may progress to severe illness that may lead to death. 

Severe complications include: 

- Severe Anemia (remember that malaria parasites infect RBCs causing it to lyse and release daughter parasites into neighboring RBCs

- Respiratory Distress  in relation to metabolic acidosis

- Cerebral Malaria

- multi-organ development. 

Bibliography: 

About Malaria. (n.d.). Retrieved April 16, 2015, from http://www.cdc.gov/malaria/about/index.html

CDC Malaria Map Application. (2015, March 12). Retrieved April 8, 2015, from http://www.cdc.gov/malaria/map/index.html

Malaria. (n.d.). Retrieved April 16, 2015, from http://www.who.int/mediacentre/factsheets/fs094/en/

Wellens, T., Hayton, K., & Fairhurst, R. (2009, September 1). JCI - The impact of malaria parasitism: From corpuscles to communities. Retrieved April 16, 2015, from http://www.jci.org/articles/view/38307/figure/1

         In the study that WHO conducted in 2001, malaria was ranked as the 8^th highest contributor to global disease problems and was ranked as the 2^nd highest contributor in Africa.

		Deaths, 2000					DALYs from deaths, 2000
		All causes		Malaria			All causes		Malaria
Region	Population	Thousands	Percent	Thousands	Percent	Malaria deaths as a percent-age of all deaths	Thousands	Percent	Thousands	Percent	Malaria DALYs as a percentage of all DALYs
World	6,122,211	56,554	100.0	1,124	100.0	2.00	1,467,257	100.0	42,279	100.0	2.90
Africa	655,476	10,681	18.9	963	85.7	9.00	357,884	24.4	36,012	85.2	10.10
Americas	837,967	5,911	10.5	1	<0.1	0.02	145,217	9.9	108	0.2	0.07
Eastern	493,091	4,156	7.3	55	4.9	1.30	136,221	9.3	2,050	4.8	1.50
Mediterranean
Europe	874,178	9,703	17.2	<1	<0.1	<0.010	151,223	10.3	20	0.04	0.01
Southeast Asia	1,559,810	14,467	25.6	95	8.5	0.70	418,844	28.5	3,680	8.7	0.90
Western Pacific	1,701,689	11,636	20.6	10	0.9	<0.09	257,868	17.6	409	1.0	0.20

Source: Deaths and DALYs from Deaths Attributable to All Causes and to Malaria by WHO Region, 2000 


        Click on the website to view an interactive map which provides updates about Malaria endemicity globally: Malaria Interactive Map
     

        In the United States, malaria had been eliminated as one of the major public health concerns in the late 1940s by eradicating reservoirs that harbor infected mosquitoes and also by promoting prevention of transmission. Nevertheless, US communities are still at risk for re-emergence of malaria, mainly influenced by American travelers who may get infected abroad. US travelers going to high risk countries should have taken anti-malarial drugs to prevent infection. 

Country	Areas with Malaria	Estimated relative risk of Malaria for US Travelers2	Drug Resistance3	Malaria Species4	Recommended Chemoprophlaxis5	Key Information Needed and Helpful Links to Assess Need for Prophylaxis for Select Countries
Afghanistan	April–December in all areas at altitudes below 2,500 m (8,202 ft).	High6	Chloroquine	P. vivax 80-90% P. falciparum 10-20%	Atovaquone-proguanil, doxycycline, or mefloquine	1) Month(s) of travel 2) City(ies) of travel 3) Altitude of city(ies) of travel Altitude information for Afghanistan
Albania	None	None	Not Applicable	Not Applicable	Not Applicable
Algeria	Rare indigenous cases	No information	Chloroquine	P. falciparum, P. vivax	Mosquito avoidance only.
American Samoa (U.S.)	None	None	Not Applicable	Not Applicable	Not Applicable
Andorra	None	None	Not Applicable	Not Applicable	Not Applicable
Angola	All	Moderate	Chloroquine	P. falciparum 90% P. ovale 5% P. vivax 5%	Atovaquone-proguanil, doxycycline, or mefloquine
Anguilla (U.K.)	None	None	Not Applicable	Not Applicable	Not Applicable
Antarctica	None	None	Not Applicable	Not Applicable	Not Applicable
Antigua and Barbuda	None	None	Not Applicable	Not Applicable	Not Applicable
Argentina	None	None	Not applicable	Not applicable	Not applicable
Armenia	None	None	Not Applicable	Not Applicable	Not Applicable
Aruba	None	None	Not Applicable	Not Applicable	Not Applicable
Australia	None	None	Not Applicable	Not Applicable	Not Applicable
Austria	None	None	Not Applicable	Not Applicable	Not Applicable
Azerbaijan	May–October in rural areas below 1,500 m (4,921 ft). None in Baku.	Very Low	None	P. vivax 100%	Mosquito avoidance only	1) Month(s) of travel 2) City(ies) of travel 3) Altitude of city(ies) of travel Altitude information for Azerbaijan
Azores (Portugal)	None	None	Not Applicable	Not Applicable	Not Applicable

 Source: US Travelers' Estimated Risk (2014)

Note that the data on the table is based on malaria cases that occured among US military personnel who travel to itineraries that do no reflect that of those of average travelers.
        Aside from US travelers, high-risk groups include young children who have underdeveloped immunity against infections and pregnant women whose immunity is decreased during pregnancy. There are areas (e.g. Latin America and Asia) that have lower risks for transmission of malaria. Hence, there are people who have reached adulthood without developing partial immunity to Malaria. These people are at great risk for being infected when exposed and may also experience fatal symptoms and illness.