Did you know that there are over 400 different species of Anopheles mosquitoes and around 40, known as vector species that can transmit malaria? A life-threatening disease, malaria is primarily found in tropical countries and is both, preventable and curable. However, without prompt diagnosis and effective treatment, a case of uncomplicated malaria can progress to a severe form of the disease, which is often fatal without treatment. Nearly half of the world’s population is at risk of malaria. In 2021, an estimated 247 million people contracted malaria in 85 countries. That same year, the disease claimed approximately 619 000 lives.
Malaria is not contagious and cannot spread from one person to another; the disease is transmitted through the bites of female Anopheles mosquitoes. Five species of parasites can cause malaria in humans and 2 of these species – Plasmodium falciparum and Plasmodium vivax – pose the greatest threat.
The theme for World Malaria Day 2023 which is observed today, April 25, is ‘Time to deliver zero malaria: invest, innovate, implement’. The World Malaria Report by World Health Organisation (WHO) says that India is among the 5 HBHI (High burden to high impact) nations in the WHO South-East Asia Region, that showed a decline in deaths, although their contributions to the malaria burden within HBHI countries is still substantial.
Dr Devaki Thatte Dalvi, an internal medicine consultant, explains the meaning of malaria, “The word malaria literally means ‘bad air’. It is common knowledge today that it is caused by the bite of an infected Anopheles mosquito. But before this discovery, people thought that bad air was the culprit. Another threat that mosquitoes bring to us is dengue fever. Both these diseases have many common features like high fever, headache, body ache, nausea, fatigue and lowering of platelet count. There is always a possibility that a person is infected with both dengue virus and malaria protozoan Plasmodium at the same time. So it is very important that blood test for both should be done in any patient with suspected dengue or malaria.”
He further adds, “There is a risk of getting a ‘false negative’ test as well. It can be misleading and cause delay in getting treatment. A false negative test means that a person is suffering from a disease and the test result is negative. So if there is a suspicion of malaria or dengue and initial blood test results are negative, it is prudent to repeat a test after some time. As of now, there is no specific antiviral drug for dengue fever and treatment of dengue fever is mainly supportive in nature. For malaria, specific anti-malarial drugs are available. There is no significant long term immunity after getting infected with dengue or malaria. So repeat infections can occur with new mosquito bites.”
Anopheles mosquito which causes malaria prefers to bite between dusk and dawn while Aedes aegypti mosquito that causes dengue fever prefers daytime for biting. The bites of Aedes are often not felt at all. So patients often wonder how they contracted dengue fever when they do not remember a single mosquito bite. “Unfortunately, we are witnessing more and more cases of dengue and malaria with each passing year. I feel each citizen should take some share in the responsibility of keeping our surrounding clean to prevent and eventually eliminate these scary infections. All living beings evolve over time and develop new mechanisms to escape threats to their existence and mosquitoes and germs are not an exception to this. It is therefore important that we limit the use of chemicals to kill mosquitoes and avoid overuse and misuse of anti-malarial drugs to prevent development of resistance,” advises Dr Devaki.
Dr Pradipta Bhattacharya, an expert intensivist and consulting physician informs, “Malaria, along with dengue fever, is becoming deadlier than ever before. Nonetheless, the number of positive malaria complications is growing faster than dengue complications. Anyone observing high-grade fever with severe chills rigors associated with weakness, abdominal pain, and headache, must visit a doctor and get themselves tested. Malaria takes many lives every year, therefore, by spreading awareness about it we can help save lives.”
What’s the difference in symptoms among malaria and dengue? Dr Pradipta says, “Malaria may be associated with pallor, tachycardia and loose motions as well mental confusion in extreme cases. While dengue is typically characterised by high fever, severe body aches, purpuric rashes, and bleeding manifestations. Antimalarials are available both orally and intravenously, so a patient can be cured if treated in time, but complicated malaria can be fatal even after treatment. Dengue is mostly treated symptomatically. Hence, Malaria identification, treatment, and prevention have become critical in tandem with Dengue. People need to stop believing in myths such as: malaria causes lifelong immunity, malaria is not deadly, malaria only occurs during rainy seasons, malaria only affects adults, malaria vaccines are sufficient, and so on.”
He adds, “Each and every doctor is doing the best to swipe away malaria from the face of our planet. Therefore, we have to come together and join hands against this disease. Furthermore, on the occasion of World Malaria Day, let’s conquer malaria by making everyone aware of it.”
Senior consultant physician, Dr Vijay Naik, clears certain myths and facts around Malaria. “It is a myth that contracting malaria once, makes you immune to it. In fact, there is no long-lasting immunity vis a vis reinfection. Eventually, exposure to sufficient strains offers protection from high-level parasitemia and disease, but not from infection. It is also a myth that malaria is not fatal. Malaria is fatal, without timely diagnosis and treatment and the risks are the same for everyone, children and adults. Another myth is that malaria does not spread in the dry season. Malaria can spread in the dry season too, but it is more common during the rains due to increased mosquito breeding and transmission,” explains Dr Vijay.
Elaborating on the warning signs for malaria and dengue in terms of mild and severe cases, Dr Vijay says, “Patients with mild forms of malaria and dengue will exhibit nausea, vomiting, headache while in severe cases, patients with malaria will experience dry cough, jaundice, convulsions and low blood sugar. Warning signs for patients with dengue in severe cases are bleeding underneath the skin, bleeding from the gums and nose, blood seen in vomit, urine or stool, difficulty or rapid breathing and fatigue, irritability or restlessness.”
How can everyone work together to eradicate the disease? “Promoting public knowledge and awareness about malaria, including its transmission, preventive measures and information about vaccination is essential for eradicating the disease. Such efforts can increase vaccine acceptance and reduce vaccine hesitancy among the population. It is critical for awareness among people about important details regarding the malaria vaccine, in addition to existing knowledge about the disease,” concludes Dr Vijay.