Vector Volume 11 Issue 2 - 2017

Dengue in the Pacific Islands
[Review]
Madeleine Marsland and Dunya Tomic
Madeleine is a fourth year medical student who is interested in global health and research.
She combines these interests in her role as Chief of Editorials and Publications
for the Pacific Medical Students’ Association, and is also undertaking research with the
Department of Anatomy and Developmental Biology at Monash University. She hopes
to pursue global health research and policy.
Dunya is a fourth year medical student at Monash University with a particular interest
in clinical research and medical ethics. She hopes to one day combine this with a
career as a physician.
Abstract
Without a fully effective vaccine, prophylactic measures, or sufficient treatment options, dengue has emerged as a significant
global health threat. The Pacific Islands are particularly susceptible to dengue as they provide favourable conditions for
the Aedes mosquito population, the vector responsible for spreading the virus. Strong public health protocols with an
emphasis on vector control are considered to be the best way to combat dengue in this region. However, for a variety of
social, economic, environmental and political factors, vector surveillance and control mechanisms are failing. This review
seeks to provide an overview on the emergence of dengue in the Pacific Islands, why this region is susceptible due to virus
“and vector factors, and what has been done and can be done in the future to contain the dengue threat in this region.
Introduction
Dengue virus is a vector-borne disease primarily
spread by the Aedes mosquito population; it is one of the
most significant infectious diseases that remains without
definitive prevention or treatment options. Due to a variety
of environmental and social factors, the Pacific Islands are
particularly susceptible to dengue and other arbovirus.[1,
2] This has significant associated morbidity, mortality and
economic cost, particularly when patients contract ‘severe
dengue’.[1-3] A diagnosis of dengue can be based on clinical
signs and/or laboratory diagnosis, whilst a diagnosis of ‘severe
dengue’ is based on serious complications including plasma
leakage, severe haemorrhage or severe organ impairment.[3]
These clinical manifestations and complications of dengue
can cause severe illness, particularly in susceptible patient
groups including children.[3]
Treatment options are limited particularly in resource
poor settings, and thus preventing dengue and recognising
outbreaks is critical.[3] Dengvaxia, a world-first dengue
vaccine, has recently been approved for use in endemic
settings, with the World Health Organization recommending
high-risk nations implement it as part of their vaccination
program.[4-6] However, the vaccine has variable levels of
efficacy, and is not yet considered a cost-effective solution.
[5, 6] Whilst dengue remains a growing threat, the Pacific
Island region must urgently develop alternative cost-effective
diagnostic, detection, treatment and prevention strategies.[4,
7, 8]
Methods
The intended focus of this literature review was dengue
in the Pacific Island region. An Ovid MEDLINE search was
conducted combining the search terms “Dengue”, “Aedes”
and “Pacific”. Grey literature and data was also sourced from
the World Health Organization (WHO) and other non-profit
organisations. Additional resources were identified through
analysing the articles retrieved through these searches.
Epidemiology
”
Prevalence
Dengue has been reported in several Pacific Island
nations since the 1950s, but in the past decade the incidence
has grown exponentially.[1, 9] Whilst in 2000 there was only
50 reported cases per 1000 people, by 2012 this had grown
to 350 per 1000.[1] It is difficult to determine reliable data
on the endemic levels of dengue in the Pacific Islands, as
this depends on accurate and timely reporting to the Pacific
Public Health Surveillance Network, still under development.
[2] However, whilst dengue is not endemic in all Pacific Islands,
it is emerging in previously untouched islands including the
Solomon Islands and Papua New Guinea.[9] From 2016 to
2017 alone, there has been an unusual increase in dengue
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