Biology Reference
In-Depth Information
5.2. Aneityum
The most unambiguous success of MDA using chloroquine/sulfadoxine pyri-
methamine (SP)/primaquine for malaria control remains the island of Ane-
ityum, a small island at the southern end of Vanuatu and the extreme southern
boundary of global malaria transmission ( Fig. 6.1 ). Nearly 90% compliance
with the medication over 9 weeks added to insecticide-treated bed nets, a
favourable epidemiology and good post-MDA surveillance for new cases man-
aged to eliminate malaria from this island of about 800 persons ( Kaneko et al.,
2000 ). For more than 20 years, malaria surveillance was continued on Ane-
ityum and visitors were not allowed onto the main island without having a
blood smear taken. During 2002 a large religious gathering resulting in an
unusual number of visitors to the island, vivax malaria was reintroduced and
rapidly became established in all villages on the island ( Kaneko, 2010 ). Addi-
tional rounds of MDA including primaquine were required in order to remove
the parasite again. Such a large concentration of malaria control resources can-
not be generally applied as on the small island of Aneityum, so one has to find
more practical approaches that can be applied to larger and less isolated areas.
Malaria elimination is favoured in isolated geographic areas such as islands
when the population can be easily accessed and introduction of new persons
potentially with new parasites can be strictly monitored at a limited num-
ber of entry points. In Sardinia, malaria eradication was aimed at mosquito
elimination which failed despite the eventual elimination of malaria ( Brown,
1998 ; Marchi and Munstermann, 1987 ). Besides the southernmost island of
Aneityum ( Kaneko et al., 2000 ), malaria elimination using 9-12 weeks of
chloroquine/SP/primaquine MDA was attempted on other isolated islands
in Melanesia, specifically the Santa Cruz Islands in the Solomon Islands as
well as Nissan Island in Papua New Guinea ( Avery, 1977 ; Rieckmann et al.,
1968 ; Rieckmann, 1963 ). These programs were in addition to DDT house
spraying and usually were attempts to eliminate residual malaria transmission
that was not disappearing in the face of concerted residual insecticide use.
MDA would reduce parasite rates but only in a few cases such as Aneityum
and Nissan was transmission actually suspended. Failure of these elimination
programs could usually be traced to either continuing foci of transmission or
reintroduction of parasites from visitors from neighbouring islands.
6. PROBLEMS OF MALARIA REINTRODUCTION
INTO ELIMINATED AREAS
The world is not static, especially given modern transportation sys-
tems that can move a person to nearly anywhere on the globe within a day.
 
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