Biology Reference
In-Depth Information
a riverine species inhabiting forest locations, it has been observed to take
advantage of deforestation, exploiting areas with reduced canopy cover com-
pared to those more densely forested locations. The larval habitats of this
species are typically clear and natural water bodies such as slow-flowing, clear
rivers and streams. Adult female
An. darlingi
are both exo- and endophagic,
though they tend to rest outdoors regardless of where their blood meal was
taken. Host preference also varies within this species as does biting activity
(time of biting), which may adapt to correspond to human behaviour (i.e. late
night human activity influences or causes late night biting by
An. darlingi
).
The Albitarsis Complex is composed of five sibling species including
the known vectors,
An. albitarsis
,
An. deaneorum
and
An. marajoara
. Members
of this complex exhibit some behaviours that are similar to
An. darlingi
, for
example, the adult females tend to rest indoors but will bite indiscriminately
without much host preference both indoors and outdoors. The larval habi-
tats tend to be clear, sunlit, freshwater.
The Americas summary
. National surveillance data have shown a wide-
spread decrease in morbidity and mortality from both major
Plasmodium
species across the American continent since 2000 (
WHO/PAHO, 2008
).
This is due largely to the successful implementation of integrated vector
management (
Roberts et al., 1997
;
Butler and Roberts, 2000
;
Rojas et al.,
2001
;
Killeen et al., 2002
;
Roberts et al., 2002
;
Shiff, 2002
;
WHO/PAHO,
2006
) and has led eight of the 21
Pv
MECs in the Americas (Argentina,
Belize, Costa Rica, El Salvador, Mexico, Nicaragua, Panama and Paraguay)
to target malaria elimination (
The Global Health Group and the Malaria
Atlas Project, 2011
). However, the prevalence estimates of
P. vivax
in the
Americas are heterogeneous with isolated areas of intense transmission
(
Fig. 1.3
C2). Vector occurrence data coverage was uniformly low in the
American
Pv
MECs. Improved vector research in the Americas will advance
the maps of species-specific distributions, which is essential for the contin-
ued success of vector management to curb malaria morbidity and mortal-
ity. Pockets of high transmission (
Pv
PR > 7%) were observed in large areas
of the region. However, it is important to note that these were generally
in areas with low population estimates. Sparse prevalence data resulted in
high uncertainty estimates in the region that were greatly reduced when
the density of the population in endemic areas was taken into consideration
(
Fig. 1.4
C).
Anopheles darlingi
appears to be the primary vector in this region;
however, eight of the potential vectors of
P. vivax
in this region lack con-
clusive evidence regarding their potential to transmit the parasite. Therefore,
further research is needed to decisively incriminate the vectors of
P. vivax
in
the Americas.