Dengue Fever
Manual
Department of Medicine
Lahore General Hospital/PGMI
Lahore
1
Dengue Fever
 Dengue virus
 Most prevalent vectorborne viral illness in the
world
 Main mosquito vector is
Aedes Aegypti and
Albopictus
 Year round transmission
Incidence
 50-100 million dengue fever infections per
year globally
 500,000 cases of severe dengue, dengue
hemorrhagic fever or dengue shock syndrome
 100-200 cases annually in U.S.
 Average case fatality 5%
Distribution
 Endemic in more than 100
tropical and subtropical
countries
 Pandemic began in
Southeast Asia after WW II
with subsequent global
spread
 Several epidemics since
1980s
 Distribution is comparable
to malaria
Virology
 Flavivirus family
 Small enveloped viruses
containing single
stranded positive RNA
 Four distinct viral
serotypes (Den-1, Den2, Den-3, Den-4)
Pathophysiology
 Transmitted by the bite
of Aedes mosquito
(Aedes aegypti and
albopictus)
 Incubation 3-14 days
 Acute illness and
viremia 3-7 days
 Recovery or progression
to leakage phase
Clinical Presentation

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•
•
•
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Spectrum of illness
non-specific febrile illness
classic dengue
dengue hemorrhagic fever
dengue shock syndrome
other (CNS dysfunction, liver failure,
myocarditis)
The course of dengue illness
3 Phases
A. Febrile Phase
B. Critical Phase
C. Recovery Phase
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Febrile Phase
Critical Phase
Recovery Phase
Dehydration; high fever may cause
neurological disturbances and
febrile
seizures in young children
Shock from plasma leakage; severe
haemorrhage; organ impairment
Hypervolaemia (only if intravenous
fluid therapy has been excessive
and/or
has extended into this period)
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Differential Diagnosis
of Dengue Fever
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D/D of Dengue Fever
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D/D of Dengue Fever
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Approach to a Patient with
Dengue Fever
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Approach to a patient with Dengue Fever
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Treatment Recommendations
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Step I—Overall assessment
History
The history should include:
– date of onset of fever/illness;
– quantity of oral intake;
– assessment for warning signs ;
– diarrhea;
– change in mental state/seizure/dizziness;
– urine output (frequency, volume and time of last
voiding);
– other important relevant histories, such as family or
neighborhood dengue,
co-existing conditions (e.g. infancy, pregnancy, obesity,
diabetes mellitus, hypertension),
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Step I—Overall assessment
Physical examination
The physical examination should include:
 – assessment of mental state;
 – assessment of hydration status;
 – assessment of hemodynamic status
 – checking for tachypnoea/acidotic breathing/pleural
effusion;
 – checking for abdominal pain,
tenderness/hepatomegaly/ascites;
 – examination for rash and bleeding manifestations;
 – tourniquet test (repeat if previously negative or if
there is no bleeding manifestation).
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Step I—Overall assessment
Investigations:
1.
2.
3.
4.
5.
CBC , PLATELET COUNT, HCT
ELECTROLYTES, CREATININE, BICARBONATE, BSR
LFT’S
URINE C/E
BLOOD GROUP
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Step II—Diagnosis, assessment of
disease phase and severity
• On the basis of evaluations of the history, physical
examination and/or full blood count and
haematocrit, confirm.
The diagnosis as dengue.
assess the phase (febrile, critical or
recovery)
Presence of warning signs
The hydration and hemodynamic status o
Needs for admission and/or referral to
emergency department.
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Step II—Diagnosis, assessment of
disease phase and severity
Hospital Admission Criteria
1.
Warning signs
Any of the warning signs if present.
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Step II—Diagnosis, assessment of disease phase and severity
Hospital Admission Criteria
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Monitoring of Dengue Fever Patients
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•
•
•
•
•
Feeling of well being
Fever
Pulse pressure, Blood pressure and Heart rate
Vomiting/loose stool and oral intake
Urine output
Blood counts specially HCT
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Management decisions
Depending on the clinical manifestations and
other circumstances,
 Patients may be sent home (Group A)

Referred for in-hospital management or (Group
B)

Require emergency treatment and urgent referral
(Group C).
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Home care for dengue
(OPD care - Group A)
• Home care card for dengue
 Adequate bed rest
 Adequate fluid intake (>5 glasses for average-sized adults
or accordingly in children)
 Milk, fruit juice (caution with diabetes patient) and
isotonic electrolyte solution (ORS) and barley/rice water.
 - Plain water alone may cause electrolyte imbalance.
 Take paracetamol (not more than 8tabs (4 Gm) per day
for adults and accordingly in children)
 Tepid sponging with water or cold water shower
 Look for mosquito breeding places in and around the
home and eliminate them
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Home care for dengue
What should be avoided?
• Do not take acetylsalicylic acid (aspirin),
mefenemic acid (ponstan), ibuprofen or other
non-steroidal anti-inflammatory agents
(NSAIDs), or steroids.
• Antibiotics are not required and they are
best avoided.
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Home care for dengue
Approach the hospital staff early if
 Bleeding
 Red spots or patches on the skin
 Bleeding from nose or gums
 Vomiting blood
 Black-colored stools
 Heavy menstruation/vaginal bleeding
 Frequent vomiting
 Severe abdominal pain
 Drowsiness, mental confusion or seizures
 Pale, cold or clammy hands and feet
 Difficulty in breathing
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In hospital management for dengue (Group B)
Compensated shock (systolic pressure)
maintained but has signs of reduced perfusion) Fluid resuscitation with isotonic crystalloid 5-10 ml/kg/hr over 1 hour
Improvement
YES
NO
Check HCT
IV crystalloid 5-7 ml/kg/hr for 1-2
hours, then:
reduce to 3-5 ml/kg/hr for 2-4 hours;
reduce to 2-3 ml/kg/hr for 2-4 hours.
If patient continues to improve, fluid can be
further reduced.
Monitor HCT 6-8 hourly.
If the patient is not stable, act according
to HCT levels:
if HCT increases, consider bolus fluid
administration or increase fluid
administration; if HCT decreases, consider
transfusion with
fresh whole transfusion.
Stop at 48 hours.
HCT
or high
Administer 2nd bolus of fluid
10-20 ml/kg/hr for 1 hour
HCT
Consider significant occult/overt bleed
Initiate transfusion with fresh whole
blood
Improvement
YES
NO
If patient improves,
reduce to 7-10 ml/kg/hr
for 1-2 hours Then
reduce further
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In Hospital Management of Dengue
Fever (Group C – Emergency care)
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Hypotensive shock
I/V fluid 20ml / kg isotonic crystalloid or colloid over 15 min
Improvement
YES
NO
Review 1st HCT
Crystalloid/colloid 10 ml/kg/hr for
1 hour, then continue with:
IV crystalloid 5-7 ml/kg/hr for 1- 2 hours;
reduce to 3-5 ml/kg/hr for 2-4 hours;
reduce to 2-3 ml/kg/hr for 2-4 hours.
If patient continues to improve, fluid can be
further reduced.
Monitor HCT 6-hourly.
If the patient is not stable, act
according to HCT levels:
if HCT increases, consider bolus fluid
administration or increase fluid administration;
if HCT decreases, consider transfusion with
fresh whole transfusion.
Stop at 48 hours.
HCT
or high
HCT
Administer 2nd bolus fluid (colloid)
10-20 ml/kg over ½ to 1 hour
Consider significant occult/overt bleed
Initiate transfusion with fresh whole
blood
Improvement
YES
NO
Repeat 2nd HCT
HCT
HCT
or high
Administer 3rd bolus fluid (colloid)
10-20 ml/kg over 1 hour
Improvement
YES
NO
Repeat 3rd HCT
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Complications of Dengue Fever
• Haemorrhagic complications
• Fluid overload
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– Ascites, Pleural effusion, Pulmonary aedema
Metabolic acidosis and electrolyte imbalance
Severe shock
Acute Respiratory Distress Syndrome
Hyperglycaemia and hypoglycaemia
Nosocomial infections
Mycocarditis
Hepatitis
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Vaccination
 No current dengue vaccine
 Estimated availability in 5-10 years
 Vaccine development is problematic as the vaccine
must provide immunity to all 4 serotypes
 Lack of dengue animal model
 Live attenuated tetravalent vaccines under phase 2
trials
 New approaches include infectious clone DNA and
naked DNA vaccines
Hospital Discharge Criteria
Clinical
No fever for 48 hours.
Improvement in clinical status (general
well-being, appetite, haemodynamic
status, urine output, no respiratory
distress).
Laboratory
Increasing trend of platelet count.
Stable haematocrit without intravenous
fluids.
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Do and don’t of Dengue Fever
Good Practice
Bad Practice
1
Administration of Paracetomal for high
fever and myalgia.
Sending patients with non-severe
dengue home with no follow-up and
inadequate instructions
2
Clinical assessment of the
haemodynamic status before and after
each fluid bolus
Administration of acetylsalicylic acid
(aspirin) or ibuprofen
3
Give intravenous fluids for repeated
vomiting or a high rapidly rising
haematocrit
No clinical assessment of patient with
respect to fluid therapy
4
Use the isotonic intravenous fluids for
severe dengue
Administration of intravenous fluids to
any patient with non-severe dengue
5
Avoid intramuscular injections
Giving intramuscular injections to
dengue patients
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Tight Glycemic control
Not monitoring blood glucose
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Prevention
Personal:
 clothing to reduce exposed skin
 insect repellent especially in early morning, late afternoon. Bed netting is of little
utility.
Environmental:
 reduced vector breeding sites
 solid waste management
 public education
Prevention
Biological:
 Target larval stage of Aedes in large water
storage containers
 Larvivorous fish (Gambusia), endotoxin
producing bacteria (Bacillus), copepod
crustaceans (mesocyclops)
Chemical:
 Insecticide treatment of water containers
 Space spraying (thermal fogs)
Public Health
 Major and escalating global public health problem
 Global demographic changes: urbanization and
population growth with substandard housing, water,
and waster management systems
 Deteriorating public health infrastructure with
limited resources resulting in “crisis management”
not prevention
 Increased travel
 Lack of effective mosquito control
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