Malaria is a blood-based disease that, in its later stages, may prove to be life-threatening. Most commonly associated with mosquitoes: this disease usually spreads from one person to another through the bite of an infected female Anopheles mosquito. Although it can be treated if diagnosed at an early stage, it can be fatal if not treated at an early stage. To enunciate, according to the World Health Organization (WHO) estimates released in 2020, approximately 241 million cases were detected, out of which 6,27,000 deaths have occurred .
In December 2016, there were about 212 million registered cases of Malaria around the globe in 2015, out of which 429,000 were fatal. This, along with nearly half of the world’s population, is at risk of being affected: with a high prevalence in sub-Saharan Africa, Southeast Asia, Latin America, and the Middle East. Early diagnosis is thus absolute to combat Malaria and avoid its severity. As proof for this, between 2010 and 2015, the incidence of Malaria fell by twenty-one per cent across the globe, and an estimated 6.8 million deaths were averted since 2001 (1).
From where does Malaria stem, and how does it spread? It is associated with the Plasmodium parasite. This parasite spreads via the bite of a female Anopheles mosquito, as mentioned earlier. However, given its blood-based nature, it can also spread when an individual’s infected blood comes in contact with that of a healthy one. These instances include and are not limited to organ or blood transfusion, use of shared needles or syringes and can also be passed from mother to child during pregnancy, causing congenital Malaria. The Plasmodium parasite usually travels to the liver and multiplies there, infecting it and destroying the patient’s red blood cells. Researchers, in their drive to find a cure and prevent any future cases of Malaria, have identified more than a hundred varieties of the parasite, out of which five of them majorly affect humans, namely:
- Falciparum: Most commonly seen in the tropical and suburban areas, especially Africa, this is a particularly dangerous strain with a causality rate of about 1 million people every year. Known to multiply rapidly, causing clogged blood vessels and severe blood loss, it usually affects the brain leading to an onset of cerebral Malaria, pulmonary oedema, etc.P. falciparum has a poor outcome.
- vivax: One of the most common strains of the parasite in Asia, Africa, and Latin America, it affects the ability to remain dormant for months, even years, affecting the liver, spleen and blood once activated. In a few cases, it causes splenic rupture secondary to splenomegaly resulting from RBC sequestration. P. Vivax usually infects immature RBC causing limited parasitemia .
- ovale: Similar to P. falciparum in terms of biological structure, this strand usually affects people with Duffy-negative blood types, seen commonly in people residing in western Africa. Earlier, it was believed that they were resistant to Malaria as their blood type acts as a natural barrier against P. falciparum. However, with the advent of P. ovale strands of the parasite, the tables had turned.
- malariae: Located worldwide, this strand of the parasite is supposed to be long lasting and can leave chronic damage to the body, given its three-day life cycle. It generally affects the renal system causing nephrotic syndrome.
- knowlesi: Seen mainly in South East Asia, this strand of the virus has a 24-hour life cycle, so the chances of a patient moving from an uncomplicated case to a serious one are rare. However, instances have been reported of severity(2).
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Symptoms for Malaria are at an odd spot: they are usually misdiagnosed for flu symptoms, mostly in places where Malaria is less common; hence doctors and people feel the likelihood of being affected by the flu is higher than that of Malaria. The symptoms of Malaria, though hard to narrow down, can be differentiated into two classes: an uncomplicated case and a severe case.
In an uncomplicated case, the patient may show symptoms of Malaria, but on further testing, no damage to any vital organs or a presence of an infection is found. These symptoms include shivering, fever, vomiting, headaches, and sweats which are usually followed by the temperature falling back to normal. These symptoms usually last for about 6-10 hours and occur in cycles. However, there are strands (P. malariae) that can have symptoms that last longer. In severe cases, the most common symptoms are fever associated with chills, impaired consciousness, respiratory distress, abnormal bleeding, clinical jaundice, and evidence of any vital organ dysfunction, resulting in poor outcomes. In some cases, it can be fatal.
Diagnosis and Treatments for Malaria:
Early diagnosis of Malaria is crucial because it will help decrease the mortality rate and improve patients’ recovery at an early stage. Earlier, parasitological confirmation via a microscope was used to confirm the presence of the parasite strand. However, this posed an issue in underdeveloped countries where such tests were not available. In light of this, a new testing method called rapid diagnostic test or RDT was introduced. This is a relatively inexpensive method of testing that tries to detect specific proteins produced by the parasite strains in the infected body from blood collected via a prick in the finger (3).
Giemsa-stained Peripheral blood smear is considered the standard test in diagnosing Malaria infection .
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The goal of treatment is to remove the Plasmodium parasite from the bloodstream for treatment. Artemisinin-based combination therapy (ACT) has been integral in this role, and it is being widely used in different countries, especially where there is a high risk of Malaria. However, as of 2015, WHO has confirmed the presence of ACT resistant strains of the parasite in five countries, namely: Cambodia, Laos, Myanmar, Thailand, and Vietnam and has not found a cure. However, ACT therapy has proven more effective in treating Malaria in endemic areas and reducing its transmission . Prevention appears the better option with the use of a Malaria vaccine in the final stages of approval, reducing the risk, especially in children. This vaccine, also called Mosquirix, will be rolled out as pilot projects in three sub-Saharan African countries, followed by the initial phase of the vaccination estimated to begin in 2018 (as of May 2017) (1).
- World Health Organisation. Malaria. who.int. [Online] [Cited: May 31, 2017.] http://www.who.int/mediacentre/factsheets/fs094/en/.
- Webberley, Helen. Malaria: Causes, Symptoms and Treatments. medicalnewstoday.com. [Online] February 23, 2016. [Cited: May 31, 2017.] http://www.medicalnewstoday.com/articles/150670.php.
- World Health Organisation. How malaria RDTs work. who.int. [Online] [Cited: May 31, 2017.] http://www.who.int/malaria/areas/diagnosis/rapid-diagnostic-tests/about-rdt/en/.
- Abanyie FA, Arguin PM, Gutman J. State of malaria diagnostic testing at clinical laboratories in the United States, 2010: a nationwide survey. Malar J2011;10:340