Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colorless, tasteless, and almost odorless crystalline chemical compound, an organochloride. Originally developed as an insecticide, it became infamous for its environmental impacts. DDT was first synthesized in 1874 by the Austrian chemist Othmar Zeidler. DDT's insecticidal action was discovered by the Swiss chemist Paul Hermann Müller in 1939. DDT was used in the second half of World War II to limit the spread of the insect-borne diseases malaria and typhus among civilians and troops. Müller was awarded the Nobel Prize in Physiology or Medicine in 1948 "for his discovery of the high efficiency of DDT as a contact poison against several arthropods". The WHO's anti-malaria campaign of the 1950s and 1960s relied heavily on DDT and the results were promising, though there was a resurgence in developing countries afterwards.
Malaria is a mosquito-borne infectious disease that affects humans and other vertebrates. Human malaria causes symptoms that typically include fever, fatigue, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. Symptoms usually begin 10 to 15 days after being bitten by an infected Anopheles mosquito. If not properly treated, people may have recurrences of the disease months later. In those who have recently survived an infection, reinfection usually causes milder symptoms. This partial resistance disappears over months to years if the person has no continuing exposure to malaria.
Plasmodium vivax is a protozoal parasite and a human pathogen. This parasite is the most frequent and widely distributed cause of recurring malaria. Although it is less virulent than Plasmodium falciparum, the deadliest of the five human malaria parasites, P. vivax malaria infections can lead to severe disease and death, often due to splenomegaly. P. vivax is carried by the female Anopheles mosquito; the males do not bite.
Mosquito control manages the population of mosquitoes to reduce their damage to human health, economies, and enjoyment. Mosquito control is a vital public-health practice throughout the world and especially in the tropics because mosquitoes spread many diseases, such as malaria and the Zika virus.
Deltamethrin is a pyrethroid ester insecticide. Deltamethrin plays a key role in controlling malaria vectors, and is used in the manufacture of long-lasting insecticidal mosquito nets; however, resistance of mosquitos and bed bugs to deltamethrin has seen a widespread increase.
The Anopheles gambiae complex consists of at least seven morphologically indistinguishable species of mosquitoes in the genus Anopheles. The complex was recognised in the 1960s and includes the most important vectors of malaria in sub-Saharan Africa, particularly of the most dangerous malaria parasite, Plasmodium falciparum. It is one of the most efficient malaria vectors known. The An. gambiae mosquito additionally transmits Wuchereria bancrofti which causes lymphatic filariasis, a symptom of which is elephantiasis.
Indoor residual spraying or IRS is the process of spraying the inside of dwellings with an insecticide to kill mosquitoes that spread malaria. A dilute solution of insecticide is sprayed on the inside walls of certain types of dwellings—those with walls made from porous materials such as mud or wood but not plaster as in city dwellings. Mosquitoes are killed or repelled by the spray, preventing the transmission of the disease. In 2008, 44 countries employed IRS as a malaria control strategy. Several pesticides have historically been used for IRS, the first and most well-known being DDT.
Anopheles dirus is a vector of malaria in Asian forested zones.
Anopheles (Cellia) subpictus is a species complex of four species of mosquito belonging to the genus Anopheles.
Rajpal Singh Yadav is an Indian scientist in the field of vector ecology and management at World Health Organization headquarters, Geneva, Switzerland. He has been working with various countries and international organizations to formulate and promote policies for public health pesticide management and vector control.
Anopheles albimanus is a species of mosquito in the order Diptera. It is found in coastal Central and South America, the Caribbean, and Mexico. It is a generalist species and capable of wide dispersion. A. albimanus is a common malaria vector.
Anopheles stephensi is a primary mosquito vector of malaria in urban India and is included in the same subgenus as Anopheles gambiae, the primary malaria vector in Africa. A. gambiae consists of a complex of morphologically identical species of mosquitoes, along with all other major malaria vectors; however, A. stephensi has not yet been included in any of these complexes. Nevertheless, two races of A. stephensi exist based on differences in egg dimensions and the number of ridges on the eggs; A. s. stephensisensu stricto, the type form, is a competent malaria vector that takes place in urban areas, and A. s. mysorensis, the variety form, exists in rural areas and exhibits considerable zoophilic behaviour, making it a poor malaria vector. However, A. s. mysorensis is a detrimental vector in Iran. An intermediate form also exists in rural communities and peri-urban areas, though its vector status is unknown. About 12% of malaria cases in India are due to A. stephensi.
Attractive toxic sugar baits (ATSBs) are oral insecticides designed to reduce malaria infections by killing the host vector – the mosquito – rather than the parasite itself.
Anopheles (Anopheles) nigerrimus is a species complex of zoophilic mosquito belonging to the genus Anopheles. It belongs to the Nigerrimus Subgroup and Hyrcanus Group of the Myzorhynchus Series. It is found in India, and Sri Lanka, Bangladesh, Brunei, Cambodia, China, Malaysia, Myanmar, Nepal, Pakistan, Thailand, and Vietnam. It is a Possible malaria and filariasis vector. It is found from ecosystems nearby water courses such as rice fields, canals, large open marshes, and also in partially sunny, shady deep pools with floating vegetation. In Sri Lanka, the adult and larval stages are known to show resistant to a range of organophosphate and carbamate insecticides. Cytologically, two karyotypic forms of A. nigerrimus are identified, as Form A and B.
Anopheles (Cellia) vagus is a species complex of zoophilic mosquito belonging to the genus Anopheles. It is found in India, Sri Lanka and Indonesia. It is a potential natural vector of malarial parasite Plasmodium falciparum, and Japanese encephalitis virus. It is highly susceptible to insecticide deltamethrin and resistant to DDT.
Quartan fever is one of the four types of malaria which can be contracted by humans.
Anopheles funestus is a species of mosquito in the Culicidae family. This species was first described in 1900 by Giles. The female is attracted to houses where it seeks out humans in order to feed on their blood, mostly during the night. This mosquito is a major vector of malaria in sub-Saharan Africa.
Anopheles atroparvus is a European species of mosquito, which was first identified in 1927. It is one of the most abundant palearctic Anopheles species belonging to the family Culicidae, commonly called mosquitoes. Although research interest in A. atroparvus has been low in the past several decades, recent concern for an increase in vector-borne disease has encouraged new research into this species.
Anopheles arabiensis is a zoophilic species of mosquito and a vector of disease endemic to Africa.
Anopheles sundaicus is a zoophilic mosquito of southeast Asia.
