This document provides information about dengue fever, including its virus, vector, transmission, clinical presentation, diagnosis, and management. It discusses the four serotypes of dengue virus and their relationship to infection and disease severity. It also describes the Aedes mosquito species that transmit the virus and the typical symptoms seen in the febrile, critical, and convalescent phases of illness. Laboratory diagnosis and case definitions are also outlined.

2. Objectives
 DEN Virus , Vector, Host
 Etiopathogenesis
 Spectrum of diseases
 Clinical features and Diagnosis
 Management
 Check list with Do’s and Don't

3. Dengue Fever
 Most common arboviral diseases world wide
 Endemic also known for epidemics
 Dengue viruses (DEN-1, DEN-2, DEN-3 and DEN-4) –
flavivirus
 Infection with one serotype provides life long
immunity that virus , but not to others
 Second infection is fatal
 Vector
Aedes aegypti and A. Albopictus

4. The Vector
 Aedes aegypti mosquito, flight range < 100 meters
 Aggressive daytime biter – under lights – bites ankles
Most active: 2 hours before sunset (5-6pm) and
morning (8-9am)
 Once infected – it has the virus until death (30 days)
 Breeds in man made household containers
 Indoor, peridomestic, fresh water mosquito
 Metallic, plastic, rubber, cement and earthen
containers - open, left or unused - get filled with water
 Air coolers, ACs, Refrigerators, Over head tanks,
4

5. Dengue Fever – Mode of Transmission
Infected
mosquito
Healthy person Infected person
Incubation Period: 3 to 14 days
Most commonly 4 to 7 days

6. Dengue Virus Infection
Production of
antibodies/presence
of enhancing Abs
Activation of
T Cells
Ag- Ab reaction with
complement activation
Production of
various chemical
mediators
Deposition on
vessels, various
tissues & platelets
Increased
vascular
permeability
Clinical
Manifestations of
coagulopathy
(Bleeding)
c/f vasculopathy
(Capillary
leakage)
-Hypotension/
Shock
-Pleural effusion
-Ascites
-Bleeding
- Organ
involvement
PATHO- PHYSIOLOGY

7. IgM
Infection
Virus
Onset of disease
Acute Phase Convalescent Phase
0-7Day 7Day 2~3Months
IgG
Life long
14Day
<ExpressionLevel>
<Time>
J Infect Dis, 1997; 176:322-30.6
Immunopathogenesis in DF

8. • APTT ⇑
• Fibrinogen ⇓
• Platelets ⇓
• DIC
• Enhanced fibrinolytic activity
• Release of heparan sulphate or chondroitin
sulfate from the glycocalyx
Coagulopathy

9. Thrombocytopenia
• IgM type of anti-platelet antibody
Antiplatelet antibodies + complements
→lysis of platelets
• Dengue viral specific antibodies
• Bone marrow hypocellularity
• Destruction of platelet in the liver and
spleen
• DIC
• Cytoadherance
• Peripheral sequestration
• Platelet dysfunction ( defect in ADP
release)

11. Close Monitoring and possibly Hospitalization
A. Undifferentiated
DF
B. F̽ever without
complication like
bleeding,
hypotension and
organ involvement
C. Without evidence
of capillary leakage
•Infants
•Old age
•Diabetes
•Hypertension
•Pregnancy
•CAD
•Hemoglobinopathies
•Immunocompromized
patient
•Patient on steroids,
anticoagulants or
immunosuppressants.
A. DF with warning signs and
symptoms
•Recurrent vomiting
•Abdominal pain/ tenderness
•General weakness/
letharginess/ restless
•Minor bleeding
•Mild pleural effusion/ ascites
•Hepatomegaly
•Increased Hct
B. DHF Gr I & II with minor
bleeds
A. DF with significant
Hemorrhage
B. (i) DHF with significant
hemorrhage with or without
shock
(ii) DHF III & IV̽ (DSS) with
shock with or without
significant hemorrhage
C. Severe organ involvement
(Expanded Dengue Syndrome)
D. Metabolites and electrolytes
abnormalities
Tertiary level careHome Management

12. Natural course of DF illness
The clinical course of illness passes
through the following three phases:
Febrile phase
Critical phase
Convalescent phase

13. Clinical features
 Incubation period 4 to 7 days
 Illness begins abruptly and followed by
three phases

14. Blanching rash Petechiae

17. Expanded Dengue Syndrome (EDS)
 Mild or Severe organ involvement may be found
in DF/DHF. Unusual manifestations of DF/DHF are
commonly associated with co-morbidities and
with various other co-infections. Clinical
manifestations observed in EDS are as follows:

18. SYSTEM UNUSUAL OR ATYPICAL
MANIFESTATIONS
CNS Encepahloathy, encephalitis, febrile seizures,
IC bleed
GI Acute hepatitis, fulminant hepatic failure,
cholecystitis, cholangitis, acute pancreatitis
RENAL ARF, HUS, Acute tubular necrosis
CARDIA
C
Cardiac arrythmias, Cardiomyopathy,
myocarditis, pericardial effusion
RESPIRA
TORY
Pulmonary oedema, ARDS, pulmonary
hemorrhage, pleural effusion
EYE Conjunctival bleed, macular haemorrhage,
visual impairment, optic neuritis

19. DENGUE IN CHILDREN
 Pediatric age have high risk of morbidity and
mortality
 recent past - paradigm shift of High incidence of
Dengue infection from paediatric age to adolescence
and adults.

20. VERTICAL TRANSMISSION AND
NEONATAL DENGUE INFECTION
 Vertical transmission 1.6 - 64%
C/F- neonates
 Mild manifestation- Mild fever , petechial rash,
thrombocytopenia, hepatomegaly.
 Severe manifestation- pleural effusion, gastric
bleeding, circulatory failure, massive
intracerebral hemorrhage
 Clinical presentation of the neonate is not
associated with maternal disease severity, dengue
immune status or mode of delivery

21. VERTICAL TRANSMISSION AND
NEONATAL DENGUE INFECTION
 Timing of maternal infection is important.
 Peripartum maternal infection increases the
likelihood of symptomatic disease in the
newborn
 Antibodies to the dengue virus in the infected
mother can cross placenta and can cause severe
dengue in the newborn infants
 Initial presentation may be bacterial sepsis, birth
trauma or other neonatal illness

22. DENGUE IN INFANTS
 Spectrum- Asymptomatic, mild to severe
disease similar to older children and adults
 Manifestations – High fever for 2-7 days
 Respiratory tract symptoms – cough, nasal
congestion, runny nose, dyspnoea
 GI symptoms – vomiting , diarrhea
 Febrile convulsions are common
 Difficult to differentiate from in the febrile
phase –pneumonia, meningoencephalitis,
measles, rotavirus

23. Dengue infection
Differential Diagnosis
Fever, petechiae
and capillary
fragility
Meningococcemia
Rickettsial infection
ITP + Fever,
HSP
malaria
Overwhelming sepsis
Salmonellosis
Malaria
Chickungunya/ other
hemorrhagic fever
Septicemia
Leptospirosis
HUS
DIC
Fever with organ hemorrhage
(GI , Renal etc)
Coagulation failure
Clinical features +
Epidemiology+
Blood indices (e,g
thrombocytopenia) +
shock

24. Case Definition
 Probable and Confirmed cases
Probable Dengue Fever
A case compatible with clinical description (Clinical
Criteria) of Dengue Fever.
(A positive test by RDT will be considered as probable due
to poor sensitivity and specificity of currently available
RDTs.)

25. Confirmed Dengue Fever
A case compatible with the clinical description of
Dengue Fever with at least one of the following:
 Isolation of the Dengue virus (Virus culture +VE)
from serum, plasma, leucocytes.
 Demonstration of IgM antibody titre by ELISA
positive in single serum sample.
 Demonstration of Dengue virus antigen in serum
sample by NS1-ELISA.
 IgG sero-conversion in paired sera after 2 weeks
with four fold increase of IgG titre.
 Detection of virus by polymerase chain reaction
(PCR).

26. LABORATORY
DIAGNOSIS IN DENGUE

27. ELISA- Based NS1 Antigen tests
 Useful in acute dengue infections
 More specific and high sensitivity
 NS1 helps detection in early phase i.e.
viremic phase
 Epidemiological significance in containing
the infection
 Commercially available for DENV

28. IgM MAC– ELISA
 Detects anti- dengue IgM antibody
 Develops by day 5 of illness
 Variability – 2-4 days and some pt 7-8 days
of the illness
 In some primary infection persists for 90
days
 Usually wanes by 60 days
 Indicates Dengue infection in the past 2-3
months

29. Isolation of Dengue Virus
 Virus is isolated if sample taken within
first 5 days of the illness and should be
processed immediately
 Specimens- acute phase serum,plasma or
washed buffy coat from the patient,
autopsy tissues –liver, spleen, lymph node
and thymus
 Isolation of virus takes 7-10 days
 Not useful in management of patients

30. POLYMERASE CHAIN
REACTION(PCR)
 RT- PCR
 Nucleic acid sequence based amplification
test
 Real- time RT PCR
 Helps in detection of dengue virus in
acute phase serum samples

31. IgG- ELISA
 Differentiate primary and secondary dengue
infections
 it indicates past infections only

32. RDT – Rapid Diagnostic Test
 Commercial RDT kits – IgM, IgG and NS1 antigen
 Results are given in 15-20 mins
 Show high rate of False positives compared with
standard tests
 Sensitivity and specificity of some RDT kits also
vary batch to batch
 WHO Guidelines – suggests not to use the kits as
first five days IgM is undetectable. Thus a false
negative result
 Reliance on these kits not recommended will give
rise to high case- fatality ratio
 Use of RDT not recommended under the program

33. COLLECTION OF SAMPLES
 Proper collection, processing, storage and
shipment of specimens.
 Take Universal precautions
 On the sample mention day of onset of fever and
day of sample collection for a guide to the
laboratory
 NS1- samples from Day 1- 5
 IgM samples beyond Day 5

34. NVBDCP recommended test for
diagnosis
 For confirmation of Dengue infection GOI
recommends
 ELISA based antigen detection test from
Day 1 onwards
 Antibody detection test IgM capture ELISA
(MAC ELISA) after 5th day of onset of
disease.

35.  Directorate of National Vector Borne Disease Control
Programme (NVBDCP), GOI has identified network
of laboratories for surveillance of dengue
infection across the country.
 These lab receive the sample, diagnose send report
regularly to district authorities for implementation of
preventive measures to interrupt transmission.
 Supply of Kits – IgM ELISA test Kits are supplied to
identified lab through NIV. For Procurement of
Dengue NS1 funds are allocated.

36. MANAGEMENT

37. Management of Dengue Fever
 Bed rest
 Tepid sponging temperature below 38.5°C
 No NSAIDS, Antipyretic of choice Paracetamol.
 Plenty of oral fluids, juices, ORS liquid.
 Passed urine at least once in 6hr
 No warning signs at defervescence
 Hematocrit daily from day 3 or after absence of
Fever if doubt of plasma leak

38.  Paracetamol to be used.
 1-2 yrs: 60-120 mg/dose
 3-6 yrs: 120 mg/dose
 7-12 yrs:240 mg/dose
 Adults: 500 mg/dose
 In children dose of Paracetamol – 15
mg/kg/dose. Can be repeated every 6
hourly depending on fever and body ache.
 Oral fluid and electrolyte therapy recommended
for patients with excessive sweating or vomiting .
 Patients should be monitored for 24- 48 hours
after they become afebrile for development of
complications

39. Management of DHF I & II
 Any person who has DF with
thrombocytepenia, high
haemoconcentration, abdominal pain,
black tarry stools, epistaxis, bleeding
from gums etc (bleeding manifestations) –
HOSPITALIZE
 MONITORED FOR SHOCK
 CRITICAL PERIOD FOR DEVELOPMENT OF
SHOCK AFTER DAY 3 AND FEBRILE TO
AFEBRILE PHASE

40. Volume Replacement Flow Chart for
Patients with DHF Grades I & II
Initiate IV Therapy 6 ml/kg/hr Crystalloid
solution for 1-2 hrs
Check HCT
Improvement
IV therapy by Crystalloid
successively reducing from
6 to 3 ml/kg/hr
Discontinue IV after 24 hrs
after further improvement

41. Volume Replacement Flow Chart for
Patients with DHF Grades I & II
Initiate IV Therapy 6 ml/kg/hr Crystalloid
solution for 1-2 hrs
Check HCT
No Improvement
increase IV 10 ml/kg/h crystalloid duration 2 hrs
No Improvement
IV Colloid Dextran (40) 10
ml/kg/hr duration 1 hr.
Blood transfusion 10ml/
kg/hr

42. Volume Replacement Flow Chart for
Patients with DHF Grades III & IV
Immediate rapid IV Therapy 10 to 20
ml/kg/hr Crystalloid solution for 1hrs
Vitals signs
Improvement
IV therapy by Crystalloid
successively reducing from
20 to 10, 10 to 6, 6 to 3
ml/kg/hr
Discontinue IV after 24 hrs
after further improvement
UNSTABLE VITAL SIGNS

43. Volume Replacement Flow Chart for
Patients with DHF Grades III & IV
Immediate rapid IV Therapy 10 to 20
ml/kg/hr Crystalloid solution for 1hrs
Vitals signs
UNSTABLE VITAL SIGNS
No Improvement
O2
HCT
falls
IV Colloid or plasma 10 ml/kg/hr
as intervenous bolus (repeat if
necessary
Haematocrit rises
Blood transfusion
(10ml/kg/hr)
IV therapy by crystalloid successively reducing the
flow from 10 to 6 and 6 to 3 ml/kg/hr. Discontinue
after 24-48 hrs

45. Calculation of the Maintenance
fluid
 Holiday and Segar formula
Body weight in
kg
Maintenance volume
for 24 hours
<10 kg 100 ml / kg
10 – 20 1000+50 ml / kg
More than 20 kg 1500+20 ml / kg

46. Monitoring Chart
Monitor Time 2:00 pm 3:00 pm 4:00 pm
Heart Rate
Respiratory Rate
Blood Pressure
Pulse Pressure
Urine Output
Temperature
Petechiae
Epistaxis
GI bleeding
Sensorium
Sign of Shock
Platelet count
Hematocrit

47. Management of severe
bleeding
 GI haemorrahge , epistaxis, haemoptysis
 urgent blood transfusion
 proper IV fluid and plasma expanders
 thromobocytopenia,
 PT/aPTT,
 liver dysfunction
 IC bleed

48. Indication of Platelet transfusion
 Platelet count less than 10000/cumm in absence of
bleeding manifestations. (Prophylactic platelet
transfusion).
 Prolonged shock with coagulopathy and abnormal
coagulogram.
 Thrombocytopenia with hemorrhage.
 Packed cell transfusion/FFP along with platelets may be
required in cases of severe bleeding with coagulopathy.
 Whole fresh blood transfusion doesn’t have any role in
managing thrombocytopenia.

49.  Indications of blood transfusion
(PRBC)
 Loss of blood (overt blood) -10% or more of total blood
volume
 Refractory shock despite adequate fluid administration
and declining hematocrit
 Replacement volume should be 10 ml/kg body wt at a
time and coagulogram should be done

50. MANAGEMENT AT PRIMARY HEALTH CARE LEVEL

51. MANAGEMENT OF DENGUE CASES AT
PRIMARY HEALTH CARE LEVEL AND REFERRAL

52. READY RECKONER
In an outbreak situation where it is not possible to admit every
patient it is important to prioritize to decide who needs in
hospital care most. The following points are important to
distinguish various situations to take decision regarding clinical
management at home or hospital:
1. Consider having a Dengue corner in the hospital during
transmission season which is functional round the clock with
adequate trained manpower with facility for
•Tourniquet test
•BP cuff of all sizes

53. Indications for domiciliary
management:
 No tachycardia
 No hypotension
 No narrowing of pulse pressure
 No bleeding
 Platelet count > 100,000/cumm
 Patient should come for follow up after 24 hours for
evaluation.
 Report to nearest hospital immediately
 Bleeding from any site (fresh red spots on skin, black stools,
red urine, nose bleed, menorrhagia )
 Severe Abdominal pain, refusal to take orally/ poor intake,
persistent vomiting
 Not passing urine for 12 hrs / decreased urinary output
 restlessness, seizures, excessive crying (young infant),
 altered sensorium

54. Criteria for discharge of patients
 Absence of fever for at least 24 hours without the
use of anti-fever therapy
 No respiratory distress from pleural effusion or
ascites
 Platelet count > 50 000/ cumm
 Return of appetite
 Good urine output
 Minimum of 2 to 3 days after recovery from shock
 Visible clinical improvement

55. DO’S AND DON’TS FOR DOCTORs
 DO’s:
 observe every hour.
 Serial platelet and haematocrit determinations,
 Timely intravenous therapy isotonic crystalloid solution.
 If the patients condition becomes worse despite giving
20ml/kg/hr for one hour, replace crystalloid solution with
colloid solution such as Dextran or plasma. As soon as
improvement occurs, replace with crystalloid.
 If improvement occurs, reduce the speed from 20 ml to 10
ml, then to 6 ml, and finally to 3 ml/kg.
 If haematocrit falls, give blood transfusion 10 ml/kg and
then give crystalloid IV fluids at the rate of 10ml/kg/hr.
 In case of severe bleeding, give fresh blood transfusion
about 20 ml/kg for two hours. Then give crystalloid at 10
ml/kg/hr for a short time (30-60 minutes) and later reduce
the speed.
 Shock - oxygen. Acidosis - sodium bicarbonate.

56. WHAT NOT TO DO:
 Do not give Aspirin or Brufen for treatment of fever.
 Avoid giving intravenous therapy before there is
evidence of haemorrhage and bleeding.
 Avoid giving blood transfusion unless indicated,
reduction in haematocrit or severe bleeding.
 Avoid giving steroids. They do not show any benefit.
 Do not use antibiotics.
 Do not change the speed of fluid rapidly, i.e., avoid
rapidly increasing or rapidly slowing the speed of
fluids.
 Insertion of nasogastric tube to determine concealed
bleeding or to stop bleeding (by cold lavage) is not
recommended since it is hazardous.

57. Conclusion
 The guidelines for diagnosis, management and referral of
cases from primary health care centre will be useful for
early referral of the cases to higher facility.
 Nursing Care is very important
 This guidelines emphasizes that all the Dengue patients do
not require platelet transfusion and platelet does not have
a prophylactic role
 High risk groups need to be monitored closely
 Monitoring fluid therapy is very crucial

58. THANK YOU