Dengue Outbreak Dynamics and Modeling

This assignment focuses on understanding the complex dynamics of dengue outbreaks. It delves into factors influencing dengue transmission, including mosquito species, environmental conditions, and human behaviors. The analysis involves studying how repeated introductions of dengue virus affect outbreak patterns and utilizes mathematical modeling to simulate and predict dengue spread. The provided references encompass a range of perspectives, from epidemiological investigations to environmental influences and the role of vitamin D in disease progression.

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Title-Dengue Fever and Public Health
Assignment Name-
Student Name
Course Name and Number
Professor
Date

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Contents
Executive Summary.....................................................................................................................3
Introduction..................................................................................................................................4
Problems / Statement of Issues....................................................................................................4
Background..................................................................................................................................5
Pre-Existing policies/Activity......................................................................................................6
Considerations and Recommendation.........................................................................................8
Conclusion.................................................................................................................................15
References..................................................................................................................................15

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Executive Summary
Dengue fever is the serious health problem in many tropical countries. It is an infectious
disease caused by the bite of Aedes aegypti mosquito. It is a viral illness that lasts for a week or
more. There are four types of viruses and the severity of the dengue fever. This disease was
known as break-bone fever as sometimes it causes severe joint and muscle pain. I am preparing
this report to provide the overview of the action taken by Department of health, Australian
Government to control this disease. Various steps are below that can help in controlling the
breeding of the mosquito at homes and near areas. No vaccine is available for this virus as on
date, to protect from a mosquito bite is the only remedy to this. Various prevention and control
measures with the advantages and disadvantages to be followed are discuss in detail.

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Introduction
Dengue is a viral disease caused by a mosquito. It is a major health concern in tropical
and subtropical regions. The rising incidence of this disease may be due to the common factors
like growing population, increasing urbanization, global warming and due to the limited success
of vector control measures by the public or by the Government. The World Health Organization
(WHO) considers dengue as a major global health challenge. Roughly 100 million infections
cases occur every year in different regions of the countries. It causes severe flu-like symptoms,
such as high fever, headache, muscle and joint pains, vomiting, skin rash. The full life cycle of
dengue involves the mosquito as a transmitter and the humans as the victim and the source of
infection.
Problems / Statement of Issues
Urbanization and the global warming have led to the significant rise in the percentage of
the cases reported of this severe disease. The mortality rate is 1-5% without treatment and less
than 1% with treatment. It is an alarming stage now for the entire Australian Government and the
people, to control this disease before this becomes an epidemic spread. Prevention and safety
steps should be followed strictly by the public to cut down the rising ratio. Although major cases
are shown in northern Australia, slowly and slowly it is becoming a public health issue in south
part as well.

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To cut down this ratio of the cases reported each year question arises, what steps should be taken
by the Government and the individuals to make themselves aware to control dengue fever? What
role can World Health Organization (WHO) play in controlling this viral disease?
Background
Dengue is a severe flu-like infection that can attack individual of all age groups, i.e.
infants, children, and adults. It is transmitted by the mosquito and occurs mainly during the rainy
season as it is the time when mosquitoes breed the most. This fever does not spread from one
person to another but transmits through the bite of infected mosquito. Common symptoms are
sudden fever, headache, joint and muscle pain and skin rashes. This disease lasts about a week or
more. Any carelessness in this type of viral infection can result in severe dengue known as
dengue hemorrhagic the complications in this can lead to collapse and sudden death. Dengue is a
global health issue as it is endemic in around many countries mainly tropical and sub-tropical
areas. Over the last decades, number has rapidly increased.
The history of Dengue fever in Australia is more than 120 years old. The first case was
reported in New South Wales in 1898.By the end of 19th century, it was spread in many coastal
areas of Australia mainly due to movement of people from one place to another and other
reasons like conservation of water in water tanks and the stagnant water around homes and
offices. Over the last ten years, 70-80 cases per year reported that has been diagnosed
serologically. Between the years 1995-2012, there were 42 outbreaks of dengue that includes
approx 3000 confirmed dengue fever cases. In the past few years, data also shows some cases of

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dengue fever are reported in South Australia also. As per the data from Health department more
than 2000 cases of mosquito-borne diseases were confirmed in Australia in last year.
The main problem lies in this; no specific treatment is available for this type of fever.
There are four types of viruses known to cause this fever in humans, and the person immune to
one of the virus can be infected by other three types of viruses. In Australia as on date, there is
no vaccine or any type of preventive medicine available to control this fever at the early stage
only best option is to prevent oneself from the mosquito bites.
Pre-Existing policies/Activity
Health department under Government of Australia has been playing a crucial role so that
epidemics of dengue can be controlled for coming future. Various laboratories in Australia are
specially design for study for these viruses and what prevention can be done so that this threat
get controlled, as this is becoming a public health problem is south parts as well. Various safety
measures are passed by the health department and local government to make the people aware of
this threat and what steps have to be taken to minimize the mosquito breeding process.
The purpose of the policies laid down by health department in this is to provide
strategic guidelines to the public on prevention and control of dengue viruses.Many guidelines
have been developed in consultation with the Communicable Diseases Network Australia
(CDNA) to provide consistent guidance and knowledge to public health units (PHUs) to further
acknowledge the public at large about the safety measures to control this virus and disease.
Series of national guidelines are ruled out by Government and below are some of the legislation
used in disease surveillance and mosquito management:-
 Public Health Act 2005.

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 Public Health regulation 2005.
 Pest Management Act 2001.
 Pest Management Regulation 2003.
Under these Public Act and Regulations, Local governments and health departments
educate the residents about how they can control mosquito breeding on their properties and
maintain the check on the water tanks and follow the compliance for maintaining water in the
water tanks. Under Pest Act and Regulations, the public is made aware of the control activities
involving knowledge on the importance of pesticide in agriculture fields and at residential areas.
It also states that pesticides and chemical activities should be conducted by the licensed pest
management team.
At International level also on timely basis guidelines and handbooks are published for
further study for case management, diagnosis step, prevention and control of dengue for the
member states. Some of them are:-
 Global Strategy for dengue prevention and control, 2012-2020.
 American Mosquito Control Association.
 Centers for Disease Control and Prevention, USA.
 World Health Organization (WHO).
WHO and International policies respond to the dengue in the following ways:-
1. Whenever any country confirms the outbreak, they support through collaborating the
networks of laboratories.
2. Provide proper guidance and technical support whenever needed.

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3. They also help in controlling the outbreak by providing the clinical training, and training
on vector control at the regional level with the help of some of its collaborating
laboratory centers.
4. These centers and policies help the countries in developing new methods and tools,
including the pesticides products and its technologies.
Some policies are incorporated at the region level also according to the density of population
and other environmental factors to prevent and control the dengue. These are approved under
the Local government and regional health centers. These include:-
 Mosquito control Association of Australia.
 Dengue and Zika mosquito prevention.
 Guidelines to minimize mosquito and biting midge problems in new development
areas.
 Treatment advise for Pest Management Technicians: For control of Dengue virus.
 Aedes aegypti, the dengue virus Surveillance Toolkit.
These policies are executed to control the larvae of this Dengue mosquito, at the early stage.
These guidelines state the background information on biology and public health importance.
These policies also assist the developers and local government in the use of land planning for
agriculture or development.
Considerations and Recommendation
Avoiding this virus spread or mosquito bite is the only best option to prevent from
dengue fever. Many measures are taken as Prevention and Control measures to fight this virus at
different area and state and country level. But prevention starts from the home itself. Some

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prevention steps that can be taken at home to protect oneself from this virus include the
following:-
 Bed nets should be used at home while sleeping.
 Use air conditioners to stay and sleep to keep away the mosquitoes.
 Long-sleeved shirts and long pants should be used to cover exposed skin.
 Pesticide should be done after a fixed interval of time; water tanks should be
cleaned on a timely basis.
 Disposing the house-waste properly and not allowing water to accumulate in any
open holes.
 Using mosquito coils and plug-in mosquito repellent devices.
The virus of Dengue fever transmits commonly from the individual travelling from one
place to another, from one part of the world to the other. Therefore, travellers to endemic
countries are advised to take the following precautions to prevent from the mosquito:-
 Be ensured that the hotel or the accommodations rooms are free from mosquitoes
by closing the window, using sprays and using bed nets.
 Seeking medical advice without any delay, if the person becomes unwell or has
symptoms of fever during or soon after the travel.
 Traveler should try to avoid the visit to the places that are prone to stagnant water
and polluted areas.
Some Dengue management plans and action steps to control and prevent the outbreak in different
areas are:-

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 If the dengue is diagnosed in a person traveling or living in the region, health authorities
respond rapidly to prevent a local spread.
 Restrictions are imposed to the travelers from overseas areas coming for blood donation
in those regions.
 Assisting and supporting local government with the implementation of mosquito
surveillance and control activities.
 Conducting public awareness activities to educate and promote among the public self-
protective measures to be taken around their homes and businesses areas.
 Supporting local government by providing the provision of expert medical advice.
 Monitoring and spraying of pesticide resistance in the relevant areas.
 Using insect repellent containing small portions of DEET, which prevent a mosquito to
breed.
Mosquito control is the only way out till now to control this virus to break into the epidemic.
Potential course of action that can be taken by the Government to control this dengue fever in my
opinion:-
1. Encouraging and monitoring the cases overseas, i.e., outside Australia and studying
the pattern of disease occurrence.
Studying the cases of epidemics worldwide can help the Government to prepare and secure
themselves before such happens in Australia. Experts should be provided with adequate training
and equipments to help in these. Government or health departments at international level should
conduct training and meet for their member state and country on the periodical basis to keep
them update.

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Advantages of this are:-
 Before the virus spread in that pattern, as attacked in some other area or country,
Australia will be prepared to fight that situation and can control the situation.
 It can be controlled at a early stage.
Disadvantages are:-
 It requires a huge cost to set up the equipment and laboratory for research.
 Specialized doctors and physicians are needed to participate in the training and meetings.
2. Circulating the generic message for educating the public about the Dengue fever.
With the help of local government and with the support of the Hospital and health departments a
simple generic text message can be circulated to the public at large on their mobile phones in the
language that is easily understood by the public at large. This text message has to be circulated at
the time before the mosquito breeding starts, i.e., before the rainy season, so that the people can
become aware and keep a check on their surroundings. Advantages of this are:-
 This is the one of the simple methods to make the public aware and communicate any
information in today’s time.
 Sending a text message is convenient for people of all age groups.
 A text message is also helpful to communicate to the people who are deaf and hearing-
impaired people.
 It is not a compulsory, that person mobile phone has to be in range for sending the
message. If the Mobile phone is switched off or is in not reachable area, message gets
delivered once it is in reachable area or is switched on.

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Disadvantages are:-
 Sometimes the message is delivered at the non-preferable time, as one might be busy
in some important meeting or may be out to some doctor or for some important piece
of work a where simple text message can distract anyone.
 The message has to be short and crisp, people might don’t have much space to get the
message across.
 Some people respond negatively to unwanted text messages. Make sure message is
sent with the required privacy and permission and data protection rules.
3. Conducting the public awareness activities time to time.
Local government with health department should conduct public awareness programs on the
periodic basis to make the people aware about this dengue fever and about all the prevention and
control measures that can be taken. Public awareness can be created through various means
which includes media awareness, using the social media and broadcasting awareness on
television and internet. Communities can be used as a public awareness in small areas and
region. Campaigning strategies can be used to make public at large aware of the dengue fever.
The monthly or weekly meeting can be held in residential and businesses areas to communicate
the important message and to communicate people about the prevention and control of this virus.
Advantages are:-
 People of all categories can be part of these activities i.e. high standard and middle- class
person.
 Social media is used by most of the public in one way or the other, through which
awareness can be easily spread.

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 Old age people like to be participating in the society meeting and all communities
meeting, through which other family members can be communicated.
Disadvantages are:-
 This is one of the time- consuming activities, which requires people to take some time
out and be part of the campaigns and meetings.
 It is an expensive task that requires proper setup and places.
Hence, recommendation would be conducting the public awareness on time to time basis to
make the public aware of this viral disease. The more awareness is created, the more the people
will take steps to make them protect against the infection and protect from the mosquito bites.
For this, a cross-sectional pilot study was conducted among the people visiting one of the
famous hospitals in some small region of Australia. Through the method of convenience
sampling, a pre-tested questionnaire was asked face- to- face as an interview with four hundred
visitors in a span of time. This was done to access the knowledge level and awareness among the
people about the dengue virus and the practices they follow in their daily routine to prevent this
growing viral infection. And the score of knowledge at the last was recorded on a scale 1-3.
Result was, about 90% of the individuals interviewed had heard about the dengue fever.
While the sufficient knowledge about this virus with early symptoms details and types was found
in only 38.5% of the individuals, who appeared for the interview. Result also showed that the
knowledge that was based upon preventive measures was found to be focused towards the
preventive measures rather than eradication of mosquito population. Use of mosquito coils and
sprays was the only best most preventive measure known among the set of people interviewed.

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As a public awareness tool, television was considered as the most important and useful source of
information about any disease.
Therefore it clarifies that public awareness activities and campaign plays an important
role to educate the public at mass level. Short documentary movie, shown on Television or any
social media can play a vital role to educate the people. Types of public awareness programs are
rolled out from time to time by health government and local government for literate and illiterate
class of people in the language commonly known among the people.
Future Actions that can be taken:-
 With the aim to prevent and treat dengue infection in the future, Control of mosquito
transmission, development of dengue virus vaccine and antiviral medicine constitute the
main action to be taken to prevent this outbreak at higher level.
 Control of mosquitoes (vector) transmission can be done by keeping species like guppies
or copepods in standing water, and infecting the mosquito population with these bacteria.
 There should be proper techniques to deal with the water waste and stagnant water
mainly during the peak rainy seasons and the deep holes if any in the near buy areas, i.e.
in home gardens and public places should be completely filled so that we can minimize
the chances of mosquitoes breeding.
 Mosquitoes also breeds in the useless tyres and empty drums kept in the houses and
garages and industries, if kept in open. Proper check should be done so that water does
not become stagnant in any case.
Due to increasing cases of epidemics and cases of enhancing severity of dengue infection,
the necessity to develop a dengue vaccine and antiviral drug has gained a considerable

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15
importance. Several laboratory test and several researches are done and carried on in many parts
of the world under the International Organization to achieve success in preparation of antiviral
drug and the vaccine. World Health organization (WHO) is constantly performing research and
is issuing guidelines on timely basis to fight this virus.
Conclusion
Dengue has become a global life- threatening public health concern, affecting around 2.5
billion individuals in more than 100 countries. The doctors and the physician should be up to
date and aware about the clinical manifestations of the prevailing condition and ensure an
adequate early treatment is available to the patient, as the dengue fever can progress to life-
threatening dengue hemorrhagic fever, which is fatal and can even cause the death of the victim.
Future directions to this combat dreadful disease aim at the methods to control the breeding of
mosquito, development of a vaccine to fight all the types of viruses of dengue and antiviral drug
regimen.
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