Abstract:
Background & objectives:
Malaria in urban and highland areas is emerging as a significant public
health threat in Kenya which has seen a dramatic increase in malaria transmission in low risk
highland areas. The objectives of the study were to find and incriminate potential vectors of malaria
in Kibera, Nairobi.
Methods:
One hundred and twenty houses within Lindi area of the southern central section of
Kibera slum in Nairobi were chosen randomly and global positioning system (GPS) mapped. Day
resting indoor mosquitoes were collected from January 2001 to December 2003. Larvae were
collected between 2002 and 2004 and reared in the insectary to adults.
Results:
A total of 176,993 mosquitoes were collected. Out of this, 176,910 were
Culex
fatigans
and 83 were
Anopheles gambiae
s.l. Mosquito population peaked during the long rains in April to
May and the short rains in November and December.
Blood meal analysis of
An. gambiae
s.l.
female mosquitoes revealed 0.97 human blood index. No mosquito was found positive for
Plasmodium falciparum
sporozoites
.
Anopheles gambiae
s.l. mosquitoes were found breeding in
polluted water and 95% of the larvae were identified as
An. arabiensis
.
Interpretation & conclusion:
Anopheles gambiae
s.l., malaria vector is present in Nairobi and it
breeds in polluted water.
Anopheles arabiensis
is predominantly preferring humans as blood meal
source, thus, showing ecological flexibility within the species
