“Malaria is an enemy that knows no borders, and its defeat requires
solidarity and collaboration.” – Ban Ki-moon
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Last April 25, the global community recognized World Malaria Day, a worldwide effort to enhance understanding of this life-threatening illness, its origins, effects, and methods of prevention. Despite progress in healthcare, malaria still impacts millions annually, particularly in isolated and under-resourced areas.
The “World Malaria Report” of the World Health Organization (WHO) for 2022 revealed that from 2000 to 2019, annual fatalities from the disease decreased from 897,000 to 568,000, while total cases fell from 245 million to 232 million.
Davao City remains a model of public health success, having upheld its malaria-free designation since its official announcement in 2021. The City Health Office (CHO) recently reported via Davao City Disaster Radio that the city’s formerly endemic areas, such as Paquibato and Marilog, have reported no malaria cases since the declaration.
“This success is a direct result of consistent and collaborative efforts among the local government, dedicated health professionals, and the engaged community, particularly in the implementation of preventive measures such as prompt diagnosis, effective vector control, and comprehensive information education campaigns,” said Melodina Babante, coordinator of the CHO’s tropical disease prevention and control division.
While many Filipinos are familiar with dengue fever, awareness of malaria is comparatively limited. Historically, knowledge about malaria has been restricted to two basic points: it is transmitted by mosquitoes and it can lead to illness. This understanding is remarkably insufficient given the significant impact malaria has had on humanity over millennia.
The disease has influenced major historical events, from nearly thwarting the construction of the Panama Canal in the 1880s to prompting the installation of mosquito netting in the Presidential suite in the early 1900s and even affecting the dynamics of World War II. In this regard, malaria has arguably left a more profound imprint on history than Adolf Hitler.
“Malaria is by far the world’s most important tropical parasitic disease and kills more people than any other communicable disease except tuberculosis,” the Geneva-based WHO deplores. “In many developing countries, malaria exacts an enormous toll in lives, in medical costs, and in days of labor cost.”
Malaria is caused by a bite of a mosquito, which has about 2,000 species. The species that transmit malaria are classified in the genus Anopheles. “About 20 different Anopheles species are locally important around the world,” the WHO says. “All of the important vector species bite at night.”
Anopheles mosquitoes reproduce in aquatic environments, with each species exhibiting distinct breeding preferences. For instance, certain species favor shallow bodies of fresh water, including puddles, rice paddies, and animal tracks.
The female Anopheles mosquitoes deposit their eggs in water, where they develop into larvae before maturing into adult mosquitoes. To support the development of their eggs, female mosquitoes require a blood meal.
Only a female mosquito that is infected can transmit the disease through its bite. “Very rarely, the disease is transmitted through a transfusion of contaminated blood or an injection with a needle that was previously used by a person with malaria,” says The Merck Manual of Medical Information.
There are four species of malaria parasites that can infect people; these are Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale and Plasmodium malariae. “Plasmodium vivax and Plasmodium ovale can remain in the liver in a dormant form that periodically releases mature parasites into the bloodstream, causing recurring attacks of symptoms,” the Merck manual says.
The WHO says symptoms of malaria usually appear 10-15 days after the infective mosquito bite. “The first symptoms – fever, headache and chills – may be mild and difficult to recognize as malaria,” the UN agency explains.
“Children with severe malaria frequently develop one or more of the following symptoms: severe anemia, respiratory distress in relation to metabolic acidosis, or cerebral malaria,” the WHO adds. “In adults, multi-organ failure is also frequent.”
According to a WHO publication, Rural Health, the malaria parasite does not merely pass from one individual to another; it requires a portion of its life cycle to be spent within a mosquito. This dependency is why malaria poses a significant health risk in tropical regions, while it is less prevalent in cooler climates or at higher altitudes, where temperatures are lower.
“The cycle of malarial infection begins when a female mosquito bites a person with malaria,” the Merck manual explains. “The mosquito ingests blood that contains malarial parasites. Once inside the mosquito, the parasite multiplies and migrates to the mosquito’s salivary gland. When the mosquito bites another person, the parasites are injected along with the mosquito’s saliva. Inside the person, the parasites move to the liver and multiply again. They typically mature over an average of one to three weeks, then leave the liver and invade the person’s red blood cells.”
At this stage, the individual who has been bitten starts to experience symptoms. Numerous individuals who have contracted malaria believe they can distinguish it from other diseases; however, this perception is misleading, as malaria can easily be mistaken for various other conditions, including flu.
If prompt treatment is not initiated, the patient’s condition may deteriorate further. “Malaria can kill an individual in just an hour, if the one being infected is not aware that he’s been bitten,” the WHO points out.
