Integrated Vector Management - Biological and Environmental Control of Disease Vectors - page 177

As highlighted in previous chapters of this
volume, several fi eld studies have combined a
biological and/or environmental tool with other
interventions to control a single disease. For
example, Mesocyclops copepods have been
integrated into an IVM programme to control
dengue in Thailand (Kittayapong et al ., 2008),
schistosomiasis was ef ectively eliminated in
Japan by a combination of improved sanitation,
molluscicides, canal lining, treatment of patients
and community involvement (see Kondradsen et
al ., Chapter 9, this volume), and malaria has
been successfully controlled in India using a
combination of indoor residual spraying (IRS)
with chemical insecticides, larvivorous fi sh, and
early detection and prompt treatment of patients
(Singh et al ., 2006), something that each
individual method would not have been able to
achieve.
However, it needs to be stressed that, for
IVM, the term 'integrated' does not necessarily
apply to a combination of more than one control
tool, or the control of more than one disease, but
to the incorporation of an ef ective intervention/s
into an integrated approach that includes the
major components described above and disease
mapping, monitoring and surveillance that can
adapt control strategies to local environments. It
has been recognized that, in the WHO Eastern
Mediterranean Region, such ef orts have been
compromised by the spread of vector resistance
to insecticides, weak management of insecticide
deployment at the national level, and the
increase in emerging and re-emerging vector-
borne diseases (Mnzava et al ., 2011). To address
these challenges, the WHO has recently provided
guidelines on policy making for IVM (WHO,
2012a) and a very comprehensive handbook for
IVM (WHO, 2012b).
One important benefi t of an IVM framework
is the potential added value of a selected
intervention impacting on more than one
vector-borne disease. This is possible where the
targeted vectors transmit more than one disease
(e.g. Anopheles can transmit both malaria and
lymphatic fi lariasis (LF), and Stegomyia mos-
quitoes can transmit LF and dengue) (WHO,
2011). Distributions of the targeted vectors and
their associated diseases can also overlap, for
example, diarrhoea and LF can be controlled by
targeting pit latrines and other human-waste
containing areas. The coordination of multi-

disease IVM could be facilitated by the use of
improved technologies and data management
systems (Eisen et al ., 2011). The remainder of
this chapter will focus on the potential of
incorporating biological and or environmental
tools for multiple disease IVM strategies.

10.3 IVM Strategies for Anopheles

Mosquitoes

The geographical distributions of LF and
malaria overlap in large areas of Africa, Asia
and the Americas (WHO, 2004a). Anopheles
mosquitoes transmit LF in rural areas of tropical
Africa and the Papuan sub-region, as well as
transmitting malaria across most of the tropical
world. To enable more cost-ef ective distribution
of resources, global vector control programmes,
such as the WHO Global Malaria Programme
(GMP) and Global Programme to Eliminate
Lymphatic Filariasis (GPELF), should work
towards synchronizing their vector control
activities where the same vector species
transmits more than one disease (van den Berg
et al ., 2012). In 36 African countries where
Wuchereria bancrofti , an agent of LF, is endemic,
it is mostly transmitted by one or two species of
Anopheles . Fortunately, malaria vector control is
already a priority for Roll Back Malaria (RBM)
programme managers, with considerable impact
on LF transmission (RBM, 2010). This synergy
should be more recognized, advocated and
exploited wherever LF and malaria are co-
endemic and have the same vectors. To date, the
most ef ective tools for the control of endophilic
vectors have been IRS with insecticide and the
use of ITNs, including long-lasting insecticidal
nets (LLINs) (WHO, 2011). ITNs and LLINs,
used for protection against malaria transmission,
also limit exposure to fi lariasis transmitted by
Anopheles mosquitoes, with signifi cant
reductions in potential transmission rates of
fi lariae (WHO, 2007). In addition, malaria
vector control activities, using ITNs and IRS,
may impact LF transmission of Culex mosquitoes
(WHO, 2011). Even the use of untreated bed
nets, in Papua New Guinea, for example, appears
to cut fi lariasis prevalence (Bockarie, 2002). To
fulfi l the goals of GMP and GPELF, to eradicate
malaria and LF, respectively, case treatment is an
essential component in addition to vector