Nairobi — RESEARCHERS IN TANZANIA HAVE attributed the rise of malaria cases in the country's highland regions to increased clearing of forests for agriculture and commercial lumbering.
Dr Leonard Mboera, a senior scientific officer with Tanzania's National Institute for Medical Research told a conference in Arusha recently: "The ecology of malaria vectors and malaria transmission are profoundly affected by perturbations on the environment, which have favoured the breeding of mosquitoes in the highlands."
Dr Mboera said a recent study by Tanzanian researchers has shown that clearing of vegetation in the East Usambara and Mbulu mountains in Tanga and Manyara regions in northern Tanzania respectively has played a significant role in the increase of malaria transmission.
Forest clearing often leaves large depressions, which can easily fill up with rainwater. It also reduces canopy cover, allowing illumination of breeding sites for malaria vectors.
He added: "The major reason for the first malaria outbreaks in the Usambara and Mbulu mountains was the availability of sites for vector breeding when rains have been prolonged into the warm seasons."
Available data shows that there have also been marked malaria epidemics in Muheza, Hanang, Babati, Mbulu, Ngorongoro, Dodoma, Mpwapwa, Lushoto and Sumbawanga.
"In all these districts, the epidemics were experienced in areas with an altitude of over 1,000 metres above sea level. Recent data from the National Malaria Control Programme show that 10 districts have reported malaria epidemics since 1996," Dr Mboera said.
Malaria epidemics have also been frequently reported in the highlands of Kenya and Uganda. In July 2002, malaria outbreaks affected over 158,000 people in Nyanza and Rift Valley provinces of Kenya.
In Tanzania malaria is the leading communicable disease. It contributes up to 40 per cent of outpatient and inpatient caseloads in children under 5 years.
In the 5-year age group, the disease contributes between 34 and 37 per cent of all admissions in health facilities. It accounts for 19 per cent of deaths in all age groups in hospitals.