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Southern Ontario Model United Nations Assembly XLV
World Health Organization (WHO): Combatting Vector-Borne Disease – Improving Immunization
Systems
Topic [002]: Combatting Vector-Borne Disease –
Improving Immunization Systems
Introduction
Vectors are living organisms that have the ability to transmit infectious
diseases between humans or from animals to humans.1 Many of these vectors are
bloodsucking insects, which ingest disease-producing microorganisms from an
infected host (human or animal) and later inject it into a new host. Mosquitoes are
the best-known disease vectors; others include ticks, flies, sand flies, fleas, triatomine
bugs and certain freshwater aquatic snails. 2 Vector-borne diseases are, naturally,
infectious diseases that are transmitted by many of the aforementioned organisms.
These diseases place a heavy social, economic, and political burden on afflicted
people, their families, and communities worldwide, with the most debilitating
repercussions occurring in developing countries. Vector-borne diseases account for
over 17% of all infectious diseases found throughout the world at any given time.3
However, their distribution is determined by a complex dynamic of environmental
and social factors. Some of the most prominent of these diseases include malaria,
World Health Organization. “Vector-borne diseases.” World Health Organization. (2016).
World Health Organization. “Vector-borne diseases.” World Health Organization. (2016).
3 Semenza, J. C. "Climate change adaptation to infectious diseases in Europe." Climate change and global health. (2009).
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World Health Organization (WHO): Combatting Vector-Borne Disease – Improving Immunization
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dengue, lymphatic filariasis, leishmaniasis, and Lyme disease.4 Vector-borne diseases
also result in a loss of productivity, school absenteeism, aggravation of poverty, high
costs for health care and place a burden on public health services.5 Oftentimes
communities are at risk for more than one vector-borne disease.
The considerable economic, ecological, and public health impacts of vectorborne diseases are expected to continue, given limited domestic and international
capabilities for detecting, identifying, and addressing potential epidemics. Much
remains to be discovered about the biology of these diseases, and in particular about
the complex biological and ecological relationships that exist among pathogens,
vectors, hosts, and their environments. Such knowledge is essential to the
development of novel and more effective intervention and mitigation measures for
vector-borne diseases as a whole.6
Current Scope of the Issue
Infectious diseases transmitted by insects and other animal vectors have long
been associated with significant human illness and death since the 17th century.7 The
early 20th century discovery that mosquitoes transmitted diseases such as malaria,
yellow fever, and dengue led quickly to the draining of swamps and ditches where
mosquitoes bred, and eventually to the use of pesticides, which reduced populations
of these disease vectors.8 The adoption of vector control measures, including the
application of a variety of environmental management tools and approaches, coupled
with improvements in general hygiene, enabled much of the world to experience
decades of respite from major vector-borne diseases in the first half of the 20th
century. This success proved fleeting, however, and vector control programs waned
due to a combination of factors including the development of pesticide resistance or
— sometimes doomed by their own success — the loss of financial support when
Huntington, Mark, and Dilip Nair. "Emerging Vector-Borne Diseases." American Family Physician. (2016).
World Health Organization. Handbook for integrated vector management. 2nd ed. Vol. 1. Paris: World Health Organization.
(2012). Print.
6 World Health Organization. “Vector-borne diseases.” World Health Organization. (2016).
7 Gubler, Duane. "Resurgent Vector-Borne Diseases as a Global Health Problem." Emerging Infectious Diseases. (1998).
8 Gubler, Duane. "Resurgent Vector-Borne Diseases as a Global Health Problem." Emerging Infectious Diseases. (1998).
4
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vector-borne diseases were no longer perceived as an important public health threat.9
Today, vector-borne diseases are once again a worldwide concern and a significant
cause of human morbidity and mortality, as Figure 1 illustrates.
Figure 1: Global mortality distribution due to vector-borne diseases as of 2004
(Source: WHO World Health Report, 2004).
Population Dynamics of Disease
The population dynamics of vector-borne pathogens are characterized by
three distinctive phenomena. First, the vectors of most of these pathogens are
arthropods, which are ectothermic.10 Since the metabolic rates of these species are
sensitive to abiotic conditions (especially temperature), demographic processes are
strongly influenced by the environment, leading to marked seasonality in disease
activity in most regions of the world. Second, vector-borne diseases are often
characterized by explosive outbreaks, especially when pathogens are introduced to
new environments, such as the Borrelia burgdorferi spirochete, which causes Lyme
disease.11 Finally, pathogens that are transmitted by species with specialized habitat
requirements occur sporadically. For example, the main vector of the Eastern Equine
Encephalitis virus (EEEV) is the mosquito Culiseta melanura, which breeds in
9 Beard, C.B et al. "Ch. 5: Vectorborne Diseases." The Impacts of Climate Change on Human Health in the United States: A
Scientific Assessment. (2016).
10 Magori, Krisztian, and John Drake. "The Population Dynamics of Vector-borne Diseases." Nature Education Knowledge.
(2013).
11 Magori and Drake. "The Population Dynamics of Vector-borne Diseases.” (2013).
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World Health Organization (WHO): Combatting Vector-Borne Disease – Improving Immunization
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cypress swamps. This mosquito spreads EEEV in the local bird community, from
which other mosquito species become infected, which can then bite humans.
Successful amplification and the distance to which EEEV spreads vary annually with
abiotic conditions, creating sporadic annual outbreaks.12
The seasonality, distribution, and prevalence of vector-borne diseases are
influenced significantly by climate factors, primarily high and low temperature
extremes and precipitation patterns.13 Climate change can result in modified weather
patterns and an increase in extreme events that can affect disease outbreaks by
altering biological variables such as vector population size and density, vector
survival rates, the relative abundance of disease-carrying animal (zoonotic) reservoir
hosts, and pathogen reproduction rates.14 Collectively, these changes may contribute
to an increase in the risk of the pathogen being carried to humans.
In addition to climate factors, multiple non-climate factors also influence
human exposure to vector-borne pathogens. Some of these include factors from an
environmental or institutional context, such as pathogen adaptation and change,
changes in vector and host population and composition, changes in pathogen
infection rates, and vector control or other public health practices (pesticide
applications,
integrated
vector
management,
vaccines,
and
other
disease
interventions). 15 Other non-climate factors that influence vulnerability to vectorborne disease include those from a social and behavioral context, such as outdoor
activity, occupation, landscape design, proximity to vector habitat, and personal
protective behaviors (applying repellents before spending time in tick habitat,
performing tick checks, etc.).16
Individual characteristics, such as age, gender, and immune function, may
also affect vulnerability by influencing susceptibility to infection. Lyme disease is
more frequently reported in children between 5 and 9 years of age and in adults
12 Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” International Journal for Parasitology:
Drugs and Drug Resistance. (2017).
13 Magori and Drake. "The Population Dynamics of Vector-borne Diseases.” (2013).
14 Beard et al. "Ch. 5: Vectorborne Diseases." (2016).
15 Zofou, Denis, et al. "Control of malaria and other vector-borne protozoan diseases in the tropics: enduring challenges despite
considerable progress and achievements." Infectious Diseases of Poverty. (2014).
16 Zofou et al. "Control of malaria and other vector-borne protozoan diseases in the tropics: enduring challenges despite
considerable progress and achievements."(2014).
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between the ages of 55 and 59, and advanced age and being male contribute to a
higher risk for severe West Nile Virus infections.17
Impacts
The majority of emerging, reemerging, and novel human infectious diseases
are zoonoses (diseases that can be transmitted from animal reservoirs to humans), of
which vector-borne diseases comprise a large percentage.18 The primary affect of
these diseases is evidently the enormous human loss of life that characterizes most
outbreaks. Rift Valley fever (RVF), for example, is a mosquito-borne disease that
affects livestock (e.g., cattle, buffalo, sheep, goats) but can also be transmitted to
humans through direct contact with the tissues or blood of infected animals, as well
as by mosquito bites.19 Outbreaks of RVF among animals can spread to humans; the
largest reported human outbreak, which occurred in Kenya during 1997–1998,
resulted in an estimated 89,000 infections and 478 deaths.20 African trypanosomiasis,
also known as African sleeping sickness, causes estimated losses in cattle production
of more than $1 billion per year, and perhaps five times that amount in lost
opportunities for development.
21
Given the rapid growth of human and
domesticated animal populations, and their increasing contact with each other and
with wild animals, the zoonotic disease threat is expected to increase.22
Vector-borne diseases have the potential to cause enormous economic harm
when they affect livestock and crops, and even the threat of infection can severely
limit trade. For example, bluetongue, a viral disease transmitted among sheep and
cattle by biting midges, results in annual losses of approximately $3 billion due to
morbidity and mortality of animals, trade embargoes, and vaccination costs.23 Vectorborne plant diseases profoundly affect agricultural productivity and ecosystem
dynamics as well. For example, emerging vector-borne viral and bacterial diseases of
17 Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
18 IOM. Microbial threats to health: emergence, detection, and response. Washington, DC: The National Academies Press.
(2003).
19 CDC. Questions and answers about Rift Valley fever. (2007).
20 CDC. Questions and answers about Rift Valley fever. (2007).
21 FAO (Food and Agriculture Organization) PAAT the disease. 2007.
22 Karesh, William B., and Robert A. Cook. "The Human-Animal Link." Foreign Affairs (2005).
23 FAO (Food and Agriculture Organization) PAAT the disease. 2007.
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citrus, most of which were introduced into the Americas since 2000, threaten 85
percent of the world’s orange juice production; similarly, annual losses in crop quality
and yield associated with certain vector-borne viruses are measured in the billions of
dollars.24
In regards to vector control, resistance to insecticides has arisen to become
an issue due to a reliance on chemical control and expanding operations, particularly
in the context of malaria and dengue. Vector control is also often not sufficiently
adapted to local or national changing circumstances as a result of inefficient
governing bodies and decision-making processes in regards to vector control. It is
necessary to base such decisions on evidence about the characteristics of local
vectors and human behavior, as well as the effectiveness of vector control methods.
Furthermore, aspects of global change, such as climate change, as previously
mentioned, environmental degradation, water scarcity and urbanization, remain
intrinsic to the distribution of vector-borne diseases.25
Mosquito-Borne Diseases
Mosquitoes are one of the deadliest animals in the world. Their ability to
carry and spread disease to humans causes millions of deaths every year. In 2015
malaria alone caused 438 000 deaths.26 The worldwide incidence of dengue has risen
30-fold in the past 30 years, and more countries are reporting their first outbreaks of
the disease.27 Zika, dengue, chikungunya, and yellow fever are all transmitted to
humans by the Aedes aegypti mosquito.28 More than half of the world’s population
live in areas where this mosquito species is present. Sustained mosquito control
efforts are important to prevent outbreaks from these diseases. There are several
different types of mosquitoes and some have the ability to carry many different
diseases, including the Aedes, Culex, and Anopheles mosquitoes. These vectors may
24 Almeida, Rodrigo. Vector-borne plant diseases: factors driving the emergence and spread of pathogens. Presentation at the
Forum on Microbial Threats workshop. (2007).
25 Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
26 World Health Organization. "Mosquito-borne diseases." World Health Organization. (2014).
27 World Health Organization. "Mosquito-borne diseases." World Health Organization. (2014).
28 Ben-Chetrit, Eli, and Eli Schwartz. "Vector-borne diseases in Haiti: A review." Travel Medicine and Infectious Disease 13.
(2015).
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be carriers of diseases such as chikungunya, Zika virus, dengue, West Nile virus,
malaria, and yellow fever.29
Often these infections are normally rare outside of certain geographic areas.
For instance, dengue hemorrhagic fever is a viral, mosquito borne illness usually
regarded only as a risk in the tropics.30 However, cases of dengue fever have been
appearing in the United States along the Texas-Mexican border – a region that has
never been seen before. In 2015 it was also reported that, due to climate change,
mosquitoes had started to spread historically rare diseases to Europe, such as malaria
to Greece, West Nile virus to eastern Europe and chikungunya to Italy and France.31
Tick and Sand-fly-Borne Diseases
Leishmaniasis is a protozoan parasitic infection caused by Leishmania
infantum that is transmitted to human beings through the bite of an infected female
sandfly.32 Temperature influences the biting activity rates of the vector, diapause, and
maturation of the protozoan parasite in the vector. Historically, sand-fly vectors
from the Mediterranean have dispersed northwards in the postglacial period based
on morphological samples from France and northeast Spain and sandflies have been
reported today also from northern Germany. 33 The biting activity of European
sandflies is strongly seasonal, and in most areas is restricted to summer months.
Once conditions make transmission suitable in northern latitudes, these imported
cases could act as plentiful source of infections, permitting the development of new
endemic foci. Conversely, if climatic conditions become too hot and dry for vector
survival, the disease may disappear in southern latitudes. Thus, complex climatic and
environmental changes (such as land use) will continue to shift the dispersal of
leishmaniasis in Europe.34
World Health Organization. "Mosquito-borne diseases." World Health Organization. (2014).
Medlock, Jolyon M., and Steve A. Leach. "Effect of climate change on vector-borne disease risk in the UK." The Lancet
Infectious Diseases. (2015).
31 Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
32 Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” International Journal for Parasitology:
Drugs and Drug Resistance. (2017).
33 Semenza, J. C. "Climate change adaptation to infectious diseases in Europe." (2009).
34 Medlock, Jolyon M., and Steve A. Leach. "Effect of climate change on vector-borne disease risk in the UK." (2015).
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Tick-borne encephalitis (TBE) is caused by an arbovirus and is transmitted
by ticks (predominantly Ixodes ricinus) that act both as vectors and as reservoirs.35
Similar to other vector-borne diseases, temperature accelerates the ticks’
developmental cycle, egg production, population density, and distribution. It is likely
that climate change has already led to changes in the distribution of Iricinus
populations in Europe. Iricinus has expanded into higher altitudes in the Czech
Republic over the last two decades, which has been related to increases in average
temperatures.36
Lyme disease (Lyme Borreliosis) is caused by Borrelia bacteria and is
transmitted through the bite of infected deer ticks.37 Many species of mammals can
be infected and rodents and deer act as important reservoirs. The disease occurs in
rural areas of Asia, north-western, central and eastern Europe and the United
States.38 The current burden is estimated at 7.9 cases per 100 000 people in the USA,
according to the United States Centres for Disease Control and Prevention.39 Since
the mid-1980s, the disease has been reported in several European countries. It is
now the most common tick-borne disease in the Northern Hemisphere.
Prevention and Control
Environmental Management: Vector Control
Insecticide-treated bednets are one of the most efficient and cost-effective
ways to protect against mosquito-borne diseases, particularly malaria. Indoor residual
spraying with insecticides is the most widely used method to control mosquitoes.40 It
is also an effective way to reduce sandflies and bugs inside homes. At least 80% of
houses in a targeted area need to be sprayed for maximum impact.41 Indoor spraying
is effective for 3 – 6 months, depending on the insecticide used and the type of
35 Zofou et al. "Control of malaria and other vector-borne protozoan diseases in the tropics: enduring challenges despite
considerable progress and achievements."(2014).
36 World Health Organization. Handbook for integrated vector management. (2012). Print.
37 World Health Organization. Handbook for integrated vector management. (2012). Print.
38 World Health Organization. Handbook for integrated vector management. (2012). Print.
39 World Health Organization. Handbook for integrated vector management. (2012). Print.
40 Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
41 Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” (2017).
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World Health Organization (WHO): Combatting Vector-Borne Disease – Improving Immunization
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surface on which it is sprayed.42 The insecticide DDT can be effective for 6 – 12
months and continues to be used in several African countries. Meanwhile, longerlasting forms of existing insecticides, as well as new classes of insecticides, are under
development for use in indoor residual spraying programmes. Factors to consider
when selecting insecticides include safety for humans and the environment, efficacy
(including duration of effectiveness), cost-effectiveness, acceptability and availability,
and the capacity and resources for safe, effective application and disposal of waste.43
Spraying outer surfaces of animal shelters, outdoor latrines and other damp
places can help control sandflies. Aerial spraying of larvae breeding sites in fastflowing rivers has been successful in helping to control blackflies that transmit
onchocerciasis. Aerial spraying has also been used to control mosquitoes during
epidemics of dengue and yellow fever.44 If used early in an epidemic, emergency
space spraying may reduce the intensity of virus transmission and provide time for
the introduction of longer-term measures. Other strategies include reducing breeding
habits by emptying reservoirs of water, biological control through the release of a
certain vector’s parasites, predators, and other small organisms, and through waste
management.45
Vaccine Development and Distribution
Vaccines are not yet commercially available for dengue, malaria, and most
vector-borne diseases, but, for many, promising vaccines are under development.
The National Institute of Allergy and Infectious Diseases (NIAID) within the United
States, for example, has launched a Phase 1 clinical trial to test an investigational
vaccine intended to provide broad protection against a range of mosquitotransmitted diseases, such as Zika, malaria, West Nile fever and dengue fever, and to
hinder the ability of mosquitoes to transmit such infections.46 Similar projects are
underway in various other countries; it remains clear, however, that it will be
Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” (2017).
Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” (2017).
44 Beard et al. "Ch. 5: Vectorborne Diseases." (2016).
45 Beard et al. "Ch. 5: Vectorborne Diseases." (2016).
46 "NIH begins study of vaccine to protect against mosquito-borne diseases." National Institutes of Health. U.S. Department of
Health and Human Services. (2017).
42
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necessary to continue to study these diseases in order to determine effective and
specific vaccination strategies. Japanese and tick-borne encephalitis vaccinations also
exist and are recommended for travellers who plan to spend one month or more in
endemic areas during the transmission season, as well as residents of affected
countries.47 Vaccination is the most important preventive measure against yellow
fever as well; the vaccine is safe, affordable and highly effective, and a single dose of
yellow fever vaccine provides life-long immunity. Yellow fever is the only disease for
which countries may require proof of vaccination as a condition of entry under the
International Health Regulations.48
Given that several new vaccines with vital implications for developing
countries have come to market recently, every effort must be undertaken to ensure
that citizens of these countries gain access to them. This will depend both on raising
additional funds and bringing prices for newer vaccines down by accelerating the
entry of emerging suppliers into these markets.49 Technology and knowledge transfer
will be crucial, and will also help emerging suppliers to assume a larger role in
stimulating vaccine research and development to meet unaddressed vaccine needs.
As such, ensuring that afflicted populations have access to such resources and
vaccinations will be a key area to focus on in looking to develop global strategies to
combat vector-borne disease on a broader scale.
International Response
In addition to the numerous and thoroughly developed national strategies for
the management of vector-borne diseases, the WHO responds to vector-borne
diseases by:
•
Providing the best evidence for controlling vectors and protecting people
against infection;
•
Providing technical support and guidance to countries so that they can
effectively manage cases and outbreaks;
47 Zofou et al. "Control of malaria and other vector-borne protozoan diseases in the tropics: enduring challenges despite
considerable progress and achievements."(2014).
48 Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” (2017).
49 Schorderet-Weber, Sandra et al. “Blocking Transmission of Vector-Borne Diseases.” (2017).
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World Health Organization (WHO): Combatting Vector-Borne Disease – Improving Immunization
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•
Supporting countries to improve their reporting systems and capture the true
burden of the disease;
•
Providing training on clinical management, diagnosis and vector control with
some of its collaborating centres throughout the world; and
•
Developing new tools to combat the vectors and deal with the disease, for
example insecticide products and spraying technologies.50
A crucial element in vector-borne diseases is behavioural change. WHO has also
been working with partners to provide education and improve awareness so that
people know how to protect themselves and their communities from mosquitoes,
ticks, bugs, flies and other vectors. For many diseases such as Chagas disease,
malaria, schistosomiasis and leishmaniasis, the WHO has initiated control
programmes using donated and subsidized medicines.51
The WHO is also responsible, in part, for the development of the integrated
vector management (IVM) strategy. In essence, IVM is a rational decision-making
process for ensuring optimal use of resources for vector control.52 The aim of the
IVM approach is to make vector control more efficacious, cost-effective, ecologically
sound and sustainable, in order to achieve national and global targets for vectorborne disease control. The transition to an IVM approach will require changes within
the health sector, in collaboration with other sectors and communities. Before a
government undertakes IVM, it must identify problems, analyse the policy
environment and formulate, implement and evaluate policies and their
instruments in order to reach its goals and objectives. Policies and policy
instruments must then be evaluated and any necessary corrective action taken.53
IVM provides a framework for improved personal protection/preventive strategies
that combine environmental management and chemical tools to provide the most
effective response to vector-borne disease outbreaks on both a local and national
level.
World Health Organization. Handbook for integrated vector management. (2012). Print.
Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
52 World Health Organization. “Vector-borne diseases.” (2016).
53 Huntington, Mark, and Dilip Nair. "Emerging Vector-Borne Diseases." (2016)
50
51
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IVM also requires a multi-sectoral approach to vector-borne disease control.
For instance Health Impact Assessments of new infrastructure development, e.g.
water resource, irrigation and agriculture, can help identify potential impacts on
vector-borne disease upstream of major policy decisions so effective action may be
taken.54 By using this tactic to combat vector-borne disease, countries around the
world can best address the issue within the scope of the resource that are available to
them.
Future Directions
Despite the extensive work done by the WHO, it is crucial to note that IVM
is not a panacea. However, in many settings, the use of IVM strategies has yielded
sustainable reductions in disease and transmission rates. In addition, certain IVM
field experiences have been documented as cost-effective in terms of disease control,
and potential generators of economic co-benefits in terms of development and
growth; more work, however, must be done in linking health and economic
outcomes.55
Despite significant efforts both at the international and local levels in
containing the burden of vector-borne infections, growing challenges remain
including the difficulties in developing effective vaccines, coupled with the various
limitations of existing therapies, the emergence and rapid spreads of resistance
against insecticides, and the available drugs.56 It is crucial to optimize the exploitation
of existing facilities through a number of approaches to drug discovery and
development. While vaccine research should continue to be supported, interventions
in vector control and drugs need special and sustained efforts. Biological tools in
vector control look highly promising and the innovation deserves a particular
attention. Finally, based on past experiences and the predominant role played by
natural products in tropical regions, it is reasonably hoped this leads (notably from
medicinal plants) merit special consideration in the development of the next
Magori and Drake. "The Population Dynamics of Vector-borne Diseases.” (2013).
Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
56 World Health Organization. Handbook for integrated vector management. (2012). Print.
54
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generation of drugs against these diseases. It is also necessary to keep in mind that
bouts of vector-borne disease are multifactorial events that, as such, call for a caseby-case assessment and targeted interventions.57
Afflicted countries must also be willing and prepared to develop strategies
that are both constructive and sustainable in regards to working in conjunction with
existing IVM frameworks. Policy-wise, future work must be done to examine the
public health impacts of pesticides used in vector management, integrate pest
management into agriculture, construct standards to incorporate measures to prevent
vector–human contact, support local health systems, prevent vector breeding, and
increase public awareness and education on the issue itself.58 Access to water and
sanitation also remains an integral factor in disease control and elimination. Thus, by
ensuring effective global collaboration and policy alignment between the WHO and
both local and national governments within afflicted countries, it is possible to most
efficiently address the underlying causes of vector-borne diseases in order to help
alleviate the social, economic, and health burdens they place on millions of people to
this day.
Pertinent Questions
What steps can be taken to improve capacity building within developing nations to
address vector control? What can be done in the case that the infrastructure for
vector control is inadequate?
How can risk management strategies for different vector-borne diseases effectively
be combined under a common framework to ensure efficiency in regards to resource
allocation?
How might mapping seasonal and predicted outbreaks help with vector
management? How might governments be able to do this?
Huntington, Mark, and Dilip Nair. "Emerging Vector-Borne Diseases." (2016)
Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases: Understanding the Environmental, Human
Health, and Ecological Connections, Workshop Summary. (2008).
57
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Do the risks for vector-borne diseases change in areas afflicted by deforestation? If
so, how might these vectors be managed both in the short-term and long-term?
Works Cited
Almeida, Rodrigo. Vector-borne plant diseases: factors driving the emergence and
spread of pathogens. Presentation at the Forum on Microbial Threats
workshop entitled “Vector-borne diseases: Understanding the environmental,
human health, and ecological connections,”; June 19–20, 2007; Ft. Collins,
CO. 2007.
http://www.nationalacademies.org/hmd/~/media/E4E4AA149C974E5CB5
A5DB2B9477D8F1.ashx
Beard, C.B., R.J. Eisen, C.M. Barker, J.F. Garofalo, M. Hahn, M. Hayden, A.J.
Monaghan, N.H. Ogden, and P.J. Schramm. "Ch. 5: Vectorborne Diseases."
The Impacts of Climate Change on Human Health in the United States: A
Scientific Assessment. N.p., April 4 2016. Accessed February 21 2017.
https://health2016.globalchange.gov/vectorborne-diseases.
Ben-Chetrit, Eli, and Eli Schwartz. "Vector-borne diseases in Haiti: A review."
Travel Medicine and Infectious Disease 13 (2015): 150-58. Science Direct.
http://www.sciencedirect.com/science/article/pii/S1477893915000307.
CDC. Questions and answers about Rift Valley fever. 2007.
http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/rvf/rvf_qa.htm.
FAO (Food and Agriculture Organization) PAAT the disease. 2007. Accessed
February 21 2017.
http://www.fao.org/ag/againfo/programmes/en/paat/disease.html.
Gubler, Duane. "Resurgent Vector-Borne Diseases as a Global Health Problem."
Emerging Infectious Diseases 4.3 (1998): 442-50.
https://wwwnc.cdc.gov/eid/article/4/3/98-0326_article.
Huntington, Mark, and Dilip Nair. "Emerging Vector-Borne Diseases." American
Family Physician 94.7 (2016): 551-57. Merican Academy of Family Physicians.
http://www.aafp.org.myaccess.library.utoronto.ca/afp/2016/1001/p551.html.
Institute of Medicine (US) Forum on Microbial Threats. Vector-Borne Diseases:
Understanding the Environmental, Human Health, and Ecological
Connections, Workshop Summary. Washington (DC): National Academies
Press (US); 2008. Summary and Assessment.
https://www.ncbi.nlm.nih.gov/books/NBK52939/.
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IOM. Microbial threats to health: emergence, detection, and response. Washington,
DC: The National Academies Press; 2003. p. 209.
https://www.nap.edu/read/10636/chapter/1.
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