This presentation provides an overview of dengue virus infection and disease. It discusses the epidemiology, transmission, clinical manifestations and diagnosis of dengue fever and dengue hemorrhagic fever. It also covers management guidelines, global strategies for prevention and control, and government initiatives in India to address dengue outbreaks.

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2. Presentation By:
Monika
IInd Year Postgraduate
Department of Public Health Dentistry
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3.  Introduction
 Some Recent Dengue Out breaks
 Clinical manifestations of dengue
 Problem statement
 Epidemiological determinants
 Transmission of disease
 Clinical and Laboratory diagnosis
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4.  WHO classification and Grading of severity of dengue
infection.
 Guidelines for treatment:
 Management of DHF Grade I, II, III and IV.
 Indications for red cell and platelet transfusion.
 Global and National strategies.
Conclusion &References.
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6.  Dengue viruses are arboviruses capable of infecting
humans and causing disease.
 It is a self limiting disease.
 A prevalence of Aedes aegypti and Aedes albopictus
together with the circulation of dengue virus of more than
one type in any particular area tends to be associated with
the out breaks.
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8.  In 2013, cases have occurred in Florida (United States of
America) and Yunnan province of China. Dengue also
continued to affect several South American countries,
notably Costa Rica, Honduras and Mexico.
 In 2014, trends indicate increases in the number of cases
in the People's Republic of China, the Cook Islands, Fiji,
Malaysia, with Dengue Type 3 (DEN 3) affecting the
Pacific Island countries after a lapse of over 10 years.
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9.  In 2015, Delhi, India, recorded its worst outbreak since
2006 with over 15 000 cases.
 In 2016, large dengue outbreaks worldwide: In the
Americas region ˃ 2.38 million cases, where Brazil alone
contributed slightly less than 1.5 million cases,
approximately 3 times higher than in 2014.
WHO: Dengue and severe dengue Fact sheet. Available from
www.who.int/mediacentre/factsheets/fs117/en/ (accessed 05 December 2017)
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10.  6 November 2017-Dengue fever – Burkina Faso
 4 August 2017 -Dengue fever – Côte d’Ivoire
 19 July 2017 -Dengue fever – Sri Lanka
WHO: Dengue and severe dengue Fact sheet. Available from
www.who.int/mediacentre/factsheets/fs117/en/ (accessed 05 December 2017)
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12. Dengue virus infection
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13. Dengue fever (DF) and its severe forms- dengue
haemorrhagic fever(DHF) and dengue shock
syndrome(DSS) have become major international public
health concerns.
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15.  Some 2.5billion people i.e. two-fifth of the world’s
population in tropical and sub-tropical countries are at risk
of the disease.
 An estimated 50 million dengue infections occur
worldwide annually and about 500,000 people with DHF
require hospitalisation.
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16.  Dengue and DHF is endemic in more than 100 countries
in the WHO regions of Africa, the Americas, Eastern
Mediterranean, South-East Asia and Western Pacific.
 Detection of all four serotypes has now rendered the
countries hyperendemic.
 The countries of South East Asia region are divided
into 3 categories:
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18.  Rapid urbanisation
 Lifestyle changes
 Deficient water management
The disease has a seasonal pattern i.e. cases peak after
monsoon.
Dengue is endemic in 35 states/Union territories. During
2014, about 40,425 cases were reported with 137 deaths.
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21.  AGENT:
 There are four virus serotypes which are designated as DENV-
1, DENV-2, DENV-3, DENV-4.
 The first infection probably sensitizes the patient while the
second infection with different serotypes appears to produce
immunological castastrophy.
 Vector: Aedes aegypti and Aedes albopictus.
 Aedes aegypti: is a highly domesticated, strongly
anthropophilic, nervous feeder (i.e. it bites more than one
host to complete one blood meal) and is a discordant
species( it needs more than one feed for the completion of
the gonotropic cycle).
 Aedes albopictus: aggressive feeder and concordant
species.
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25.  Infants and elderly
 Pregnancy
 Peptic ulcer disease
 Women who are in menstruation or abnormal bleeding
 Haemolytic disease e.g. G-6PD etc.
 Congenital heart disease
 Chronic disease such as diabetes mellitus, hypertension,
asthama e.t.c. 25

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27.  Infants, children and adults who have been infected with
dengue virus especially for the first time(i.e. primary
dengue infection), may develop a simple fever
indistinguishable from other viral infection.
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28.  Incubation period: 3 to 10 days.
 Onset is sudden, with chills, high fever, intense head ache,
muscle and joint pain
 With in 24hours retro orbital pain develops.
 Extreme weakness, anorexia, constipation, altered taste
sensation, sore throat.
Fever- 39̊ C - 40̊ C
Fever lasts for about 5days rarely 7 days after which
recovery is usually complete although convalescence may
be protracted.
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29.  It is a severe form of dengue fever.
 Course is divided into three phases: febrile phase, critical
phase and recovery phase.
Febrile phase: following incubation period of 4-6days.
Temperature: 40̊ C- 41̊ C.
CLINICAL DISTICTIVE CHANGES: Rising haematocrit
value, moderate to marked thrombocytopenia.
Positive tournicate test:
The test is performed by inflating a blood pressure cuff
to a mid point between systolic and diastolic blood
pressure for 5 minutes.
In DHF, test gives 20 petechiae or more.
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30.  When temperature drops to 37.5- 38̊ C or less usually on
days 3-7 days of illness an increase in capillary
permeability in parallel with increasing haematocrit
levels- beginning of critical phase.
Pleural effusion mostly on right side and ascites clinically
detectable, gall bladder edema has been found to precede
plasma leakage.
Those who improve is said to have non severe dengue
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31.  If the patient survives the 24-48 hours critical phase, a
gradual reabsorption of extravascular compartment fluid
takes place in the following 48-72 hours.
 Haematocrit stabilizes, white blood cell count starts to rise.
 Respiratory distress from massive pleural effusion and ascites
will occur if excessive intravenous fluids have been
administered.
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32.  It is defined by one or more of the following:
a) Plasma leakage may lead to shock and/or fluid
accumulation with or without respiratory distress
b) Severe bleeding
c) Severe organ impairment
 The patient is considered to have shock if the pulse
pressure is ≤20 mm of Hg in children or he/ she has
signs of poor capillary perfusion (cold extremities,
delayed capillary refill or rapid pulse rate)
 In adults, pulse pressure of ≤20 mm of Hg may indicate
a severe shock. Hypotension is associated with
prolonged shock complicated by major bleeding.
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33.  Dengue fever:
 Acute febrile illness with two or more of the following:
Headache
Retro-orbital pain
Myalgia
Arthralgia/bone pain
Rash
 Haemorrhagic manifestations
 Leucopenia ( WBC ≤ 5000 cells/mm3 )
 Thrombocytopenia (platelet count ˂150,000 cells/mm3 )
Confirmed diagnosis can be given by:
 Isolation of dengue virus from serum, CSF or autopsy
samples.
 Fourfold or greater increase in serum IgG.
 Detection of dengue virus or antigen in tissue, serum or
cerebrospinal fluid
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34. All of the following:
 Acute onset of fever of two to seven days duration
 Haemorrhagic manifestations: positive tourniquet test,
petechiae, ecchymosis or purpura, or bleeding from
mucosa, gastrointestinal tract e.t.c
 Platelet count ≤ 100,000 cells/mm3
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35.  Criteria for dengue haemorrhagic fever as above with
signs of shock including:
 Tachycardia, cool extremities, delayed capillary refill,
weak pulse, lethargy which may be a sign of reduced brain
perfusion.
 Pulse pressure≤20 mmHg with increased diastolic
pressure e.g. 100/80 mmHg
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37.  Rapid and accurate diagnosis is of paramount importance
for : (1) clinical management (2) epidemiological
surveillance (3) Research and (4) Vaccine trials.
 Epidemiological surveillance requires early determination
of dengue virus infection during out break for urgent
public health action towards control as well as sentinel
sites for detection of circulating serotypes.
The following laboratory tests are available to diagnose
dengue fever and DHF:
 VIRUS ISOLATION
 VIRAL NUCLEIC ACID DETECTION
 IMMUNOLOGICAL RESPONSE
 VIRAL ANTIGEN DETECTION
 RAPID DIAGNOSTIC TEST
 ANALYSIS OF HAEMATOLOGICAL PARAMETERS.
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42.  A full blood count of the patient should be done at the first
visit.
 A haematocrit test in the early febrile phase establishes the
patient’s own baseline haematocrit.
 A rapidly decreasing platelet count in parallel with a rising
haematocrit compared to the baseline is suggestive of
progress to the plasma leakage/critical phase of the
disease.
In the absence of the patients baseline, age specific
population haematocrit levels could be used as a
surrogate during the critical phase.
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44. These are patients who are able to tolerate adequate
volumes of oral fluids and pass urine at least once
every six hours, and do not have any of the warning
signs, particularly when fever subsides.
Those with stable haematocrit can be sent home after
being advised to return to the hospital immediately if
they develop any of the warning signs:
 Encourage intake of oral rehydration solution
(ORS), fruit juice and other oral fluids containing
electrolytes and sugar to replace losses from fever
and vomiting.
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45.  Give paracetamol for high fever if the patient is
uncomfortable.
 The interval of paracetamol dosing should not be less than
six hours.
 Tepid sponge if the patient still has high fever.
Instruct the care givers that the patient should be brought to
hospital immediately if any of the following occur;
 No clinical improvement
 Deterioration around the time of defervescence
 Severe abdominal pain
 Persistent vomiting
 Cold and clammy extremities
 Bleeding(e.g. black stools or coffee ground vomiting)
 Not passing urine for more than 4-6 hours.
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47.  The management of febrile phase is similar to DF.
 Patients should be closely monitored for the initial signs of
shock.
 The critical period is during the transition from the febrile to
the afebrile stage usually occurs after the third day of illness.
 Haematocrit should be determined daily from the third day
until the temperature has remained normal for one or two
days.
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49.  Any person who has dengue fever with thrombocytopenia
and haemoconcentration and presents with abdominal pain
with abdominal pain, black tarry tools, epistaxis, bleeding
from gums and infection etc needs to be hospitalised.
 A rise of haemoconcentration indicates need for fluid
therapy.
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52.  Common signs of complication are observed during the
afebrile phase of DHF.
 Immediately after hospitalisation, the haematocrit, the
platelet count and vital signs should be examined to assess
the patient’s condition and Intravenous fluid therapy
should be started.
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55.  Loss of blood- 10 percent or more of total blood volume-
preferably give whole blood or components to be used.
 Replacement volume should be 10ml/kg body weight at a
time and coagulogram should be done.
 If fluid overload is present packed cells are to be given.
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57.  Prophylactic platelet transfusion may be given at level of
˂ 10,000/cu.mm.
 Prolonged shock with coagulopathy and abnormal
coagulogram.
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59.  Absence of fever for at least 24 hours without the use of
anti-pyretic drugs.
 Return of appetite.
 Visible clinical improvement.
 Good urine output.
 Minimum of 2-3 days after recovery from shock.
 No respiratory distress from pleural effusion or ascites.
 Platelet count ˃ 50,000/cu.mm.
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61.  In dengue endemic countries, cases of suspected, probable
and confirmed dengue should be notified as soon as
possible so that appropriate health measures can be
initiated.
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63.  preventing mosquitoes from accessing egg-laying habitats
by environmental management and modification;
 disposing of solid waste properly and removing artificial
man-made habitats;
 covering, emptying and cleaning of domestic water
storage containers on a weekly basis;
 applying appropriate insecticides to water storage
outdoor containers;
 using of personal household protection such as
window screens, long-sleeved clothes, insecticide
treated materials, coils and vaporizers;
 improving community participation and mobilization
for sustained vector control;
 applying insecticides as space spraying during
outbreaks as one of the emergency vector-control
measures;
 active monitoring and surveillance of vectors should be
carried out to determine effectiveness of control
interventions.
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64.  CYD-TDV is a prophylactic, tetravalent, live attenuated viral
vaccine.
 Vaccination schedule- 3 injections of 0.5 mL administered at 6-
month intervals.
 The indication from the first licenses is for the prevention of
dengue illness caused by dengue virus serotypes 1, 2, 3, and 4
in individuals 9–45 years or 9–60 years of age (depending on
the license), living in dengue endemic areas. 64

65.  The goal of the global strategy is to reduce the burden of
dengue. Its specific objectives are:
 To reduce dengue mortality by at least 50percent by 2020
 To reduce dengue morbidity by at least 25percent by 2020
 To estimate the true burden of the disease by 2015.
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67. Government of India has taken various steps for prevention
and control of Dengue in the country as detailed below:
 Developed a Long Term Action Plan for Prevention and
Control of Dengue in the country and sent to the State(s) on
January 2007 for implementation.
GOI initiatives for Dengue and Chikungunya. Available from
nvbdcp.gov.in/dengue-goi-activities.html (accessed 05 December 2017).
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68.  National guidelines for clinical management of Dengue
Fever, Dengue Haemorrhagic Fever, Dengue Shock
Syndrome has been sent to the State(s) April 2007 for
circulation in all hospitals.
GOI initiatives for Dengue and Chikungunya. Available from
nvbdcp.gov.in/dengue-goi-activities.html (accessed 05 December 2017).
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69.  Established 110 Sentinel Surveillance Hospitals with
laboratory support for augmentation of diagnostic facility.
All these are linked with 13 Apex Referral Laboratories.
 To maintain the uniformity and standard of diagnostics in
these laboratories ELISA test kits are provided through
National Institute of Virology (NIV), Pune. Cost is borne
by GOI.
Sentinel Surveillance Hospitals in Karnataka:
APEX REFERRAL LABORATORY IN
KARNATAKA:
National Institute of Mental Health
& Neuro-Sciences, Bangalore
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70.  Diagnosis of Dengue is provided to the community at free of
cost.
 Ensuring the diagnostic facility and availability of kits is the
responsibility of the respective State Programme Officers,
NVBDCP.
 A Mid Term plan has been approved by Committee of
Secretaries (CoS) on 26/5/2011 for prevention and control of
Dengue which have been shared with the States for
implementation.
Octalogue
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72.  Dengue is the most rapidly spreading mosquito-borne viral
disease, with a 30-fold increase in global incidence over the
past 50 years.
 Dengue is a global concern, with a steady increase in the
number of countries reporting the disease, currently close to
75% of the global population exposed to dengue are in the
Asia-Pacific region.
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73.  Mortality from dengue can be reduced to almost zero by
implementing timely, appropriate clinical management,
which involves early clinical and laboratory diagnosis,
intravenous rehydration, staff training and hospital
reorganization.
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75.  Park K. Park’s Textbook of Preventive And Social
Medicine. 23rd ed. Jabalpur (India): M/s Banarsidas
Bhanot;2015. p261-271.
 Wallace B.R. Public health and Preventive Medicine. 15th
ed. New Delhi(India):McGraw Hill. P91-92.
 WHO (2012), Global Strategy For Dengue Prevention and
Control, 2012-2020.
 Govt. of India(2014), Operational Guidelines National
Programme for prevention and control of Dengue.
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76.  WHO: Dengue and severe dengue Fact sheet. Available from
www.who.int/mediacentre/factsheets/fs117/en/ (accessed 05
December 2017)
 Bhatt S, Gething PW, Brady OJ, Messina JP, Farlow AW,
Moyes CL et.al. The global distribution and burden of
dengue. Nature;496:504-507.
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77.  W.H.O. Dengue: guidelines for diagnosis, treatment,
prevention and control. WHO/HTM/NTD/DEN/2009.1.
World Health Organization; 2009.
 GOI initiatives for Dengue and Chikungunya. Available
from nvbdcp.gov.in/dengue-goi-activities.html (accessed
05 December 2017).
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