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of point records per country were from Kenya ( n = 757), followed by Tan-
zania and Cameroon ( n = 383 for both nations). For the most part, the
other countries on the continent had less than 100 point records, with
the exception of Burkina Faso ( n = 310), Equatorial Guinea ( n = 113),
Ghana ( n = 106), Madagascar ( n = 198), Mali ( n = 166), Nigeria ( n = 190),
Senegal ( n = 209), Sudan ( n = 125), the Gambia ( n = 192) and Uganda
( n = 135). African countries classified as P. vivax endemic that had very
few (≤5) vector occurrence point records were Central African Republic
( n = 3), Congo ( n = 2), Liberia ( n = 4), Namibia ( n = 5) and Togo ( n = 1).
The compiled species distribution maps ( Fig. 1.9 E) illustrate a relatively
straightforward picture of the distribution of the region's DVS: Anopheles
arabiensis , An. funestus s.l. , and An. gambiae s.l. which all have broad distribu-
tions in the region and are confirmed vectors of P. vivax . These three DVS
dominate in heterogeneous ranges of different pairs and combinations (of
one another) in such a way that the species are present on their own in only
focused locations. The co-dominant range of the An. funestus complex and
An. gambiae in Central Africa is surrounded by an 'envelope' that houses
all three primary DVS, that is further surrounded by An. arabiensis and the
Funestus Complex, and then only An. arabiensis on the periphery. Anoph-
eles arabiensis tolerates drier environments and is therefore absent from the
forested areas of western Central Africa. The An. funestus complex distribu-
tion indicates a presence throughout all of sub-Saharan Africa, including
Madagascar, but excluding much of southern Africa. Anopheles gambiae has a
more complex distribution across a band from East (including Madagascar)
to West Africa.
The bionomics of all the African DVS of malaria are summarised in full
elsewhere ( Sinka et al., 2010a ). Here, we briefly describe the behaviours of
those three DVS identified as potential P. vivax vectors in the region. Anoph-
eles arabiensis , An. funestus s.l. , and An. gambiae s.l. are known to be primary
vectors of P. falciparum , but have also been incriminated as vectors of P. vivax
through the detection P. vivax circumsporozoite proteins in wild-caught
specimens ( Table 1.2 ). Anopheles arabiensis is often described as zoophilic,
exophagic and exophilic, yet its behaviour appears to be quite variable,
depending on location. For example, An. arabiensis found in West Africa
are generally more anthropophilic and endophagic than those in the East.
Such behavioural variability may enhance this species' ability to transmit P.
vivax (or any human malaria) allowing it to adapt to avoid control methods
such as IRS. Moreover, with peak biting times ranging from evening (1900)
to early morning (0300), An. arabiensis may also avoid control via ITNs.
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