**1. Introduction**

Human Malaria is still a serious problem in sub-Saharan Africa and the risk exists throughout the region. It is a real fact that most malaria cases and deaths occur in sub-Saharan Africa. This region has some of the poorest countries of the world with 90% of deaths occurring (approximately 3,000 deaths each day) [1]**.** The disease remains one of the leading causes of morbidity and mortality in the tropics. It is the most important and widespread of the tropical deadly diseases.

It exacts a heavy toll of illness and death on children and pregnant women [2].

In 2008, there were 247 million cases of malaria and nearly one million deaths – mainly among children living in sub-Saharan Africa [3]. A child dies every 45 second as a result of malaria, the disease accounts for 20% of all childhood deaths [3]. Malaria kills 3,000 children every day in sub-Saharan Africa—that is, a million a year [4].

In sub-Saharan Africa, many households, even children are familiar with malaria, where it has a reputation of causing teeth chattering chills, shakes and fever.

Specific population risk groups include:


Malaria**,** a Pending Problem in Sub**-**Saharan Africa 5

sub -Saharan Africa where its fatality as a result of virulent *P. falciparium* is a far greater

Anaemia is another malaria complication that can lead to death. It occurs when *P*. *falciparium* disrupts the erythrocytes and so decreases the production of erythrocytes. The pathology associated with *P*. *falciparium* malaria is in particular due to adherence of infected red blood cells in the brain causing metabolic disturbances and organ dysfunction [5].

What of the devastating effect on children? Those children who succumb to the infection but survive are often left damaged. Recurrent infections can leave the child listless and with a poor appetite. It reduces social interaction, leading to poor development. Two percent of children who survive the cerebral form of the disease are left with learning difficulties and

Malaria is transmitted by the *Anopheles* mosquito which carries infective sporozoites stage in its salivary glands which it injects into the human blood stream during a blood meal. Several *Anopheles* mosquitoes have been incriminated as the major malaria vectors. About 20 different *Anopheles* species are locally important around the world. The vector population in sub-Saharan Africa is uniquely effective, with the six species of the *Anopheles gambiae* complex being the most efficient vectors of human malaria in the region, and often considered the most important in the world [4]. *An. funestus* is also capable of producing very high inoculation rates in a wide range of geographic, seasonal, and ecological conditions. These vectors have proven effective in transmitting the malaria parasite to humans across the region, in rural and urban areas alike. *An. pharoensis* is also widely distributed in Africa, geographically and ecologically, and can maintain active transmission

All of the important vector species bite at night. They breed in still waters or shallow collections of freshwater like puddles, rice fields, and hoof prints. Transmission is more intense in places where the mosquito is relatively long-lived (so that the parasite has time to complete its development inside the mosquito) and where it prefers to bite humans rather than other animals. For example, the long lifespan and strong human-biting habit of the African vector species is the underlying reason why more than 85% of the world's malaria deaths are in sub-Saharan Africa [3]. Mosquito's habits therefore determine the geographic spread of the disease. Malaria transmission is variable from one area to the other and this will impact on its epidemiology and control. In a study by Oyewole *et al* [7] in a coastal area of southern Nigeria in sub-Saharan Africa, several species of *Anopheles* mosquitoes occurred in sympatry. These species all combined to the transmission of malaria in the area. They were all competent vectors. For a mosquito to transmit malaria to man or other hosts the

Vectoral capacity has been used interchangeably to describe the ability of mosquitoes to serve as a disease vector. It is defined qualitatively and is influenced by such variables as vector density, longetivity and vector competence. Vectoral capacity takes into account environmental, behavioral, cellular and biochemical factors that influence the association

problem than in most parts of the world [4].

conditions such as spasticity and epilepsy [4].

of malaria even in the absence of the main malaria vector.

**4. The malaria vector** 

following points are crucial:

i. Vector capacity and competence:

The following factors have made malaria a pending problem in sub-Saharan Africa.
