*3.1.1 Environmental factors*

*Malaria*

malaria.

stagnant waters [7].

**2. Mosquitoes as deadly insect vectors**

genera transmits malaria even more than wild fire!

**3. The adaptability of the** *Anopheles* **mosquitoes**

life span of the mosquito before it can transmit malaria [6].

are some of the secrets behind their success [8].

**3.1 The environment and the human malaria vectors**

Mosquitoes are slender, fragile, flying insects of about 3–6 mm in the order Diptera (true flies) within the invertebrate super-phylum Arthropoda. These insects are the deadliest animals on the planet earth, transmitting not only malaria parasites but also filariasis, yellow fever, dengue fever, Zika virus, Mayaro virus, Ross River virus, West Nile virus, Rift Valley fever, Japanese encephalitis, St. Louis encephalitis, chikungunya, and other pathogens and bringing death and misery to millions every year [4]. There are about 40 mosquito genera, and Africa is the home to three important, efficient, and deadly mosquito genera which are *Anopheles*, *Culex*, and *Aedes* species [5]. The female *Anopheles* belonging to one of these deadly

Malaria is a problem in the tropics and not in temperate regions of the world. In the temperate countries, there are mosquitoes, but the life of the malaria parasite inside the mosquito is a race against time. The time taken for the malaria parasite to go through its growth and development is close to the average life span of the mosquito itself. This period is longer in the temperate areas where the survival of the parasite is on the knife edge, and temperature below certain point reduces the

The adaptability of *Anopheles* mosquitoes in the tropics and the ability to thrive in variety of habitats are a big challenge, and this is tantamount to greater spread of

Mosquitoes naturally infest ponds, marshes, puddles, swamps, and other wetland habitats. However, mosquitoes can also breed in any collection of still or

Adult female mosquitoes may live up to a month in extreme cases in captivity but up to 2 weeks in nature. They are poikilothermic and have amazing adaptability such as suctorial mouthparts, holometabolous life cycle, and great diversity which

Both male and female *Anophele*s mosquitoes feed on sugary and plant juices as source of energy, flight, and dispersal. However, only the female mosquitoes feed on blood which is required every 2–3 days for the maturation of its eggs as the plant sources are inefficient. This blood sucking instinct is a mandatory biological process [9]. Female mosquitoes mate once in a lifetime and require still waters to oviposit. Mosquito goes through four stages during its life cycle. The first three stages egg, larva, and pupa are aquatic, but the adult is aerodynamic but may also rest on vegetation. More so, in Africa, malaria-carrying mosquitoes typically bite between dusk and dawn which coincides with the sleeping patterns of the people [3, 6].

Distribution and incidence of vector-borne diseases are determined by the ecological conditions that favours them [10]. There is a relationship between the environment and mosquito abundance [11]. There are evidences that mosquito can adapt to environmental changes and even water pollution [12]. Today's mosquito breeds even where we thought they can never thrive due to environmental changes [9]. It has been established that climatic factors have profound influences on mosquito's life span [13]. As ecosystems are being modified across the planet, the habitat is altered, and malaria territories are being extended because of global warming.

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These include factors such as temperature, rainfall and humidity which are important factors for mosquito development, and longevity [15]. Changes in the local environment are important as they create or reduce the number of suitable breeding sites for vectors, so affecting their abundance and transmission pattern [16]. Temporal and spatial changes in temperature, precipitation, and humidity under different climatic conditions will affect the biology and ecology of malaria vectors and consequently the risk of malaria transmission [15].
