A 1-year longitudinal study was conducted in Magugu in Babati district, northern Tanzania to determine malaria vector population structure and malaria transmission indices. Mosquitoes were sampled using the Centre for Disease Control (CDC) light traps. A total of 110,357 adult female mosquitoes were collected.
Anopheles gambiae
s.l. accounted 25% of the total female mosquito collected. Relatively fewer
An. funestus were collected. Other mosquito species collected were
An. pharoensis, An. coustani, An. maculipalpis, An. marshallii,
Culex quinquefasciatus
,
Cx unnivittatus,
Mansonia uniformis
and
Ma. africana. An analysis by Polymerase Chain Reaction revealed that
An. arabiensis was the only member of the
An. gambiae complex in the collected samples. The number of mosquito collected correlated with the increasing mean rainfall. Blood meal analysis showed a higher human enzymatic reaction among
An. gambiae s.l. (63.5%) followed by
An. funestus (42.9%). Bovine enzymatic reaction was higher among
An. coustani (73.7%) followed by the
An. pharoensis (66.7%). The Enzyme Linked Immunosorbent Assay (ELISA) was used to detect
Plasmodium falciparum
circumsporozoites proteins in 10,000 female
Anopheles
mosquitoes. Only two
An. arabiensis were found to be infected. The entomological inoculation rate (EIR) was estimated at 0.51 infectious bites per person per year. This EIR was considered to be relatively low, indicating that malaria transmission in this area is low. Variability in mosquito blood meal shows availability of variety of preferred blood meal choices and impact of other factors inhibiting mosquito-human host contact.The study has provided information considered useful in the mapping of the vector distribution and population structure in the country. Such information is considered to be among the essential tools for planning malaria control interventions.
