By Dr. Muralee Mohan Choontharoo
Mangaluru, April 25, 2019: World Malaria Day is commemorated every year on 25th April to recognize the global efforts to control Malaria. Globally 3.3 billion people in 106 countries are at risk of Malaria. In 2012, Malaria caused an estimated 6, 27,000 death, mostly among Africans children. Asia, Latin American and to some extent the Middle East and parts of Europe are also affected. World Malaria Day was established in May 2007 by the 60th session of the world health assembly, WHO’s decision making body.
The day was established to provide “Education and understanding of Malaria” and spread information on year – long intensified implementation of national Malaria control strategies, including community based activities for Malaria prevention and treatment in endemic areas. The theme for celebration change from year to year. The theme for 2013, 2014 and 2015 is “Invest in the future, defeat Malaria.” The theme for 2016 celebrations is “End Malaria for Good”. In 2015, 214 million people have been affected globally and 4, 38,000 people have died because of Malaria globally. Out of which 90% death occurs, in sub – Saharah African and 70% of deaths are children under five. Since 2000 Malaria has cost sub - Saharan African country 300 million dollars each year for the case management alone.
What is Malaria? :-Malaria is a life threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes. It is caused by plasmodium parasites. These plasmodium parasites are called as Malaria Vectors’. There are 5 parasite species that cause Malaria in humans and of those species plasmodium falciparum and plasmodium vivax pose the greatest threat. Plasmodium falciferum is the most prevalent Malaria species on the African subcontinent. It is responsible for most malaria, related deaths globally. Plasmodium vivax is the dominant malaria parasite in most countries outside of sub – Saharan Africans.
Symptoms :-Malaria is an acute febrile illness. In a non – immune individual, symptoms appear 7 days or more usually, 10 – 15 days after the infective mosquito bite. The first symptoms fever, headache, chills and vomiting. Symptoms may be mild and difficult to recognise as malaria. If not treated within 24 hours. P. Falciparum malaria can progress to sever illness, often leading to death.
Children with severe malaria frequently develop one or more of the following symptoms, severe anaemia and respiratory diseases in relation metabolic acidosis or cerebral malaria. In adults, multi organ, involvement is also frequent. In malaria endemic areas, people my develop partial immunity, allowing asymptomatic infections to occur.
Transmission:- In most adults, malaria is transmitted through the bites of female Anopheles mosquitoes. There are 400 species of anopheles mosquito, and around 30 are malaria vectors of major importance. All of the important vector species bite between dust and dawn. The intensity of transmission depends on factors related to the parasites, the vector, the human host, and the environment. Anopheles mosquitoes lay their eggs in water which hatch into larvae, eventually emerging as adult mosquitoes. The female mosquitoes seek a blood meal to nurture their eggs. Each species of anopheles mosquito has its own preferred aquatic habitat for example some prefer small, shallow collections or fresh water, such as puddles and foot prints, which are abundant during for rainy season in tropical countries.
Transmission also depends climatic conditions that may affect the number and survival of mosquitoes, such as rainfall patterns, temperature and humidity. In many places, transmission is seasonal with peak during and just after the rainy season. Malaria endemics can occur when climate and other conditions suddenly favour transmission in areas where people have little or no immunity to malaria. They can also occur where people with low immunity move into areas with intense malaria transmission, for instance to find work or as refugees.
Prevention:-Vector control is the main way to prevent and reduce malaria transmission. If coverage of vector control intervention within a specific area is high enough then a measure of protection will be conferred across the community. WHO recommends protection of all people at risk of malaria with effective malaria vector control. Two forms of vector control are (a) Insecticide – treated mosquitoe nets and (b) Indoor residual spraying, are effective in a wide range of circumstances. Long lasting insecticide nets (LLINs) are the preferred form of insecticide – treated mosquitoe nets for public health programs. Indoor residuals spray (IRS) with insecticide is a powerful way to rapidly reduce malaria transmission. Indoor sprayer is effective for 3 -6 months, depending on the insecticide formulation used and the type of surface on which it is sprayed.
Antimalarial drugs can also be used to prevent malarias. For travellers, malaria can be prevented through chemo prophylaxis, which suppresses the blood stage of malaria infections, thereby preventing malaria disease.
Diagnosis and treatment :-Early diagnosis and treatment of malaria reduces diseases and prevents death. It also contributes to reduce the malaria transmission. The best available treatment, particularly for P. Falciperum malaria, is artemisinin based combination therapy.
WHO recommends that all cases of suspected malarias be confirmed usually parasite based diagnostic testing (Either Microscope or rapid diagnostic test) before administering treatment. Results of parasitological conformation can be available in 30 minutes or less. Treatment, solely on the basis of symptom should only consider when a parasitelogical diagnosis is not possible. The dosage, type of treatment will be decided by your doctors only based on the nature of the diseases.
Vaccines against Malarias :- There are currently no licenced vaccines against malaria or any other human parasites. One research vaccine against faliciparun, known as RTS, S/ASO1 is most advanced. This vaccine has been evaluated in a large clinical trial in 7 countries in Africa and received a positive opinion by the European medicines agency in July 2015.
Dr Muralee Mohan Choontharu is a Dental Surgeon and Dakshina Kannada District Commandant of Home Guards. He also runs a dental clinic and trauma care cente at Hosangdi in Manjeshwar is a past president of the Mangaluru chapter of Indian Dental Association and District unit of the Indian Red Cross Society.