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Figure 1.1 The Lysenko map of global malaria endemicity. The map was digitised
from its original source ( Lysenko and Semashko, 1968 ) where endemicity classes were
defined by parasite rate (PR) in children between 2 and 10 years old (hypoendemic
<10%, mesoendemic 11-50%, hyperendemic 51-75%), with the exception of the holo-
endemic class (>75%) where the parasite rate was defined in the 1-year age cohort.
The 'epidemic' class is restricted to the temperate regions in these maps and it should
be noted that this term is used differently today. For a colour version of this figure, the
reader is referred to the online version of this topic.
malaria at the peak of its historic distribution ( circa 1900) using expert opin-
ion, temperature ranges and rainfall isohyets ( Lysenko and Semashko, 1968 ;
Lysenko and Beljaev, 1969 ; Kaneko et al., 1998 ).
Lysenko's endemicity map was not specific to one human malaria
parasite. The map was created before the advent of geographic informa-
tion systems (GIS) and lacks geographic precision - as exemplified by a
significant misplacement of the Nile River. Relative to the remote sensing
data available today, the environmental data Lysenko and Semashko used to
refine the endemicity boundaries were both limited and crude. The evi-
dence base used was not described in detail and, since the map was not gen-
erated via a formal statistical method, there was no measure of uncertainty
provided. It is therefore difficult to determine how robust the distribution
estimates of Lysenko were.
3. SPATIAL DISTRIBUTION OF P. VIVAX MALARIA,
POPULATIONS AT RISK AND ITS VECTORS
Here, we bring together maps at the regional level ( Fig. 1.2 ) of the
limits of transmission, endemicity and estimates of the populations at risk,
along with the distribution of P. vivax vectors.
 
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