What is Malaria: Symptoms, causes & treatment

Overview:

Malaria is a leading cause of death and disability in low-income countries and marginalized populations. It is prevalent in tropical and subtropical regions. It spreads to humans through mosquito bites.

In 2022, there were an estimated 249 million malaria cases and 608,000 malaria deaths in 85 countries. Most of the malaria cases and deaths are from African countries.

What is Malaria?

Malaria is a life-threatening disease that spreads to humans through the bites of mosquitoes infected by malaria parasites. When these infected mosquitoes bite you, they inject malaria parasites into your bloodstream.

Symptoms can be mild such as fever, chills, and headache, or life-threatening such as confusion, seizures, and difficulty breathing.

Malaria mostly spreads to humans through the bites of infected female Anopheles mosquitoes. Moreover, blood transfusion from an infected person and sharing contaminated needles can also transmit malaria parasites into your body.

Malaria disease is preventable and curable by avoiding mosquito bites and using medicines.

Types of Malaria Parasites:

There are five species of Plasmodium (single-celled malaria parasites) that can infect humans and cause illness:

• Plasmodium falciparum (or P. falciparum)
• Plasmodium malariae (or P. malariae)
• Plasmodium vivax (or P. vivax)
• Plasmodium ovale (or P. ovale)
• Plasmodium knowlesi (or P. knowlesi

P. falciparum and P. vivax – pose the greatest threat. P. falciparum is the deadliest malaria parasite that can cause cerebral malaria(the most severe form of malaria).

In cerebral malaria, parasite-filled blood cells block small blood vessels in your brain, leading to brain swelling or brain damage. It can cause coma and death.

Cerebral malaria is responsible for about 15% of deaths in children and 20% of adult deaths.

High-Risk Areas:

Although malaria disease occurs globally, it is still common in tropical and sub-tropical countries where it’s hot and warm climates such as:

• Africa.
• Central and South America.
• South and Southeast Asia.
• Eastern Europe.
• Dominican Republic, Haiti, and other areas in the Caribbean.
• Islands in the Central and South Pacific Ocean (Oceania).

The WHO African Region carries a disproportionately high share of the global malaria burden. In 2022, the Region was home to 94% of malaria cases (233 million) and 95% (580 000) of malaria deaths. More than 80% of malaria deaths in the region in 2022 involved children under the age of 5 years old.

More than half of the global malaria deaths occur in just four African countries and those are Nigeria(26.8%), the Democratic Republic of the Congo (12.3%), Uganda (5.1%), and Mozambique (4.2%).

Symptoms:

Symptoms usually start within 10–15 days after being bitten by an infected mosquito.

Common symptoms include:

• Fever
• Chills
• Sweating
• Headache
• Diarrhea
• Abdominal pain
• Nausea or vomiting

Severe symptoms include:

• Extreme fatigue
• Difficulty breathing
• Anemia
• Jaundice(yellowing of the skin and eyes)
• Abnormal bleeding
• Dark or bloody urine
• Multiple convulsions
• Impaired consciousness
• Inability to drink or vomit

However, sometimes parasites can live in your body silently for up to a year without causing any symptoms.

Causes:

Malaria is caused by a single-celled parasite called Plasmodium, which is mostly transmitted to humans by the bite of an infected female Anopheles mosquito.

When a female anopheles mosquito bites a person infected with malaria, the mosquito gets infected. When this mosquito bites some other person, they also get infected with malaria.

Apart from mosquito bites, blood transfusion from infected persons, and contaminated needles can also transmit malaria.

Risk Factors:

• High-prone areas: Living or visiting areas where malaria is common is the greatest risk factor for getting malaria. This disease is most common in tropical and sub-tropical regions such as Africa, Central & South America, South & Southeast Asia, and the Pacific Islands.

• Particular age or condition: Infants, young children(under 5 years), older people, pregnant women, travelers, and people with HIV or AIDS are at increased risk of severe disease or dying from malaria.

• Lack of healthcare facilities: People who can’t afford or have access to good healthcare facilities are more likely to have severe complications from malaria disease.

Treatment:

Treatment for malaria involves the use of antimalarial drugs. The choice of treatment depends on factors such as the species of the malaria parasite, the severity of the infection, and whether the patient has any drug resistance or underlying conditions.

Here are the main steps in the treatment:

Treatment of uncomplicated Malaria (mild form):

• Artemisinin-based combination therapies (ACTs): These are the standard treatment for uncomplicated malaria caused by P. falciparum and other species.
• Chloroquine: Used in areas where there is no chloroquine resistance, especially for P. vivax and P. ovale.
• Primaquine: Added for P. vivax and P. ovale to prevent relapses.

Treatment of Severe Malaria (life-threatening form, often due to P. falciparum):

• Intravenous (IV) Artesunate: This is the recommended treatment for severe malaria and is given in hospital settings. Artesunate is preferred over quinine due to better outcomes and fewer side effects.
• Intravenous Quinine or Quinidine: Alternative treatment, though less preferred due to toxicity and more frequent side effects.
• Supportive care: Includes fluid management, blood transfusions (if needed for severe anemia), and treatment for complications like acute respiratory distress syndrome (ARDS) or kidney failure.
• After IV treatment, patients are switched to oral ACTs once they are stable.

Special Considerations:

• Drug-Resistant Malaria: In regions with known drug resistance, alternative ACTs or combinations of drugs may be used based on local guidelines.
• Pregnant Women: Pregnant women are treated with ACTs (except in the first trimester, where quinine or clindamycin may be used). In severe cases, IV artesunate is preferred.
• Children: Children with uncomplicated malaria are treated similarly with weight-based dosing of ACTs. In severe malaria, IV artesunate is the treatment of choice.

Prevention:

If you live in or traveling to an area where malaria is common, take steps to protect yourself from mosquito bites and prevent malaria by:

• Covering your skin: Cover your skin by wearing full pants and long-sleeved shirts. Tuck in your shirt, and tuck your pant legs into socks.

• Applying insect repellent to skin: Apply insect repellent to your skin to avoid mosquito bites. These repellents should contain DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-3,8-diol (PMD) or 2-undecanone. Do not use a spray directly on your face. Do not use products with oil of lemon eucalyptus (OLE) or p-Menthane-3,8-diol (PMD) on children under age 3.

• Applying repellent to clothing: Sprays that contain permethrin are safe to apply to clothing.

• Using a bed net: Always sleep under a bed net, particularly those treated with insecticides(such as permethrin) to prevent mosquito bites.

• Taking medicines: If you are planning a trip to visit malaria-prone areas, consult your doctor about taking medicines to prevent malaria. You can take medicines before, during, and after your trip. However, these drugs or medicines can’t be used for treatment if you do develop malaria despite taking them.

• Getting vaccine: WHO has recommended broad use of the RTS, S/AS01 malaria vaccine among children living in regions with moderate to high P. falciparum malaria, which causes severe infections in children.

Conclusion:

Malaria is a life-threatening disease caused by a parasite that spreads to humans through the bites of infected female Anopheles mosquitoes.

Each year, nearly 290 million people are infected with malaria, and more than 400,000 people die of the disease.

However, it is preventable and curable. You can protect yourself from mosquito bites and prevent malaria by covering your skin, applying mosquito repellent on your skin and clothing, sleeping under a bed net, taking medicines, and getting vaccinations.