1. DENGUE AND ITS MANAGEMENT

2. COUNTRIES / AREAS AT RISK OF DENGUE TRANSMISSION

3. DENGUE : EPIDEMIOLOGY
Average Annual No. Of Dengue Fever Cases Reported To WHO And Average Annual Number Of Countries Reporting Dengue

4. DENGUE FEVER : INTRODUCTION
‘Break-bone fever’
(Haddi tod bukhar)
Four dengue virus serotypes, i.e. Dengue 1-4.
Infection with one serotype provides life-long immunity against reinfection by that same serotype, but not against the other serotypes.

5. DENGUE FEVER : INTRODUCTION
Principal mosquito vector is Aedes aegypti .
Adult mosquitoes shelter indoors and bite during the daytime.
Other vectors of less importance:
Ae albopictus,
Ae polynesiensis
Ae scutellaris

6. LIFE CYCLE OF AEDES MOSQUITO

7. DENGUE FEVER : INCUBATION PERIOD
Incubation Period : Commonly, it is 5-6 days ( 3-10 days )

8. DENGUE FEVER : PATHOPHYSIOLOGY
Risk of severe disease is increased at least 15-fold during repeat (secondary) compared to primary dengue infections .
Various mechanisms suggested :
Antibody-dependent enhancement or ADE ,
Complement activation by virus-antibody complexes
T-cell mediated immunopathology

9. DENGUE FEVER : PATHOPHYSIOLOGY
DOMINANT HYPOTHESIS ADE :
SECONDARY INFECTION
PRE-EXISTING NON-NEUTRALISING ANTIBODIES OPSONISE THE VIRUS
ENHANCES VIRAL UPTAKE AND REPLICATION IN MACROPHAGES.
LEAD TO HIGHER VIRAL LOADS

10. DENGUE FEVER : PATHOPHYSIOLOGY
DOMINANT HYPOTHESIS ADE :
LEAD TO HIGHER VIRAL LOADS
INFECTED MONOCYTES TO RELEASE VASOACTIVE MEDIATORS
THROMBOCYTOPENIA, VASCULOPATHY, COAGULOPATHY
ENDOTHELIAL DAMAGE LEADS TO CAPILLARY LEAK OR FRANK BLEED
MANIFESTATIONS OF SEVERE DENGUE

11. DENGUE FEVER : PRESENTATION
Symptomatic Dengue Infection
Undifferentiated fever
Dengue Hemorrhagic Fever
Dengue Fever
Without Hemorrhage
With Unusual hemorrhage
Dengue Shock Syndrome
No Shock

12. DENGUE FEVER : WHO CASE DEFINTION
􀂄 Fever or history of acute fever, lasting 2-7 days, occasionally biphasic.
􀂄 Bleeding (Haemorrhagic tendencies)
– A Positive Tourniquet Test (TT)
– Petechiae, Ecchymosis, Or Purpura
– Bleeding From The Mucosa, Gastrointestinal Tract, Injection Sites Or Other Locations
– Haematemesis Or Melena

13. DENGUE FEVER : WHO CASE DEFINTION
􀂄 Thrombocytopaenia (100,000 cells / mm3 or less)
􀂄 Evidence of plasma leakage due to increased vascular permeability:
– Rise in haematocrit > 20%
– Drop in haematocrit following volume-replacement treatment > 20%
– Pleural effusion, Ascites, and Hypoproteinaemia.

14. WHEN TO SUSPECT DENGUE FEVER
In background of epidemic:
Unusual rise in fever cases
Associated with bleeding manifestation
Fever not associated with URI symptoms

15. DENGUE FEVER Acute febrile illness of 2-7 days duration
(BIPHASIC) with two or more of the following manifestations:
Ø Headache
Ø Retro -Orbital Pain
Ø Myalgia / Arthralgia
Ø Rash
Ø Thrombocytopenia May Be Present.
Ø Leukopenia ocassinally.
There is no evidence of plasma loss.
In children:
Fever, nausea , vomiting, Hepatomegaly, thrombocytopenia more common

16. DENGUE DISEASE COURSE 0 2 4 6 8 10 12 14 16 18 IgG MOSQUITO BITE IgM
AFEBRILE
CRITICAL
HEMORRHAGE
SHOCK
Thrombocyto--penia
IgG
MOSQUITO BITE
IgM
FEVER
VIREMIA
RECOVERY

17. The dengue NS1 antigen-capture ELISA gave an overall sensitivity of % and a specificity of 100%. The sensitivity was significantly higher
in acute primary dengue (97.3%) than in acute secondary dengue (70.0%).
The positive predictive value of the dengue NS1 antigen-capture ELISA was 100% and negative predictive value was 97%.

18. TREATMENT : DENGUE FEVER & DHF

44. SOME TREATMENT PRINCIPLES
MONITOR
B L O O D P R E S S U R E
HEMATOCRIT
PLATELET COUNTS

45. SOME TREATMENT PRINCIPLES
BLOOD PRESSURE
Narrow pulse pressure (<20 mm Hg)
Hypotension for age (this is defined as systolic pressure < 80 mmHg for those less than five years of age, or < 90 mmHg for those five years of age and older.
HEMATOCRIT
Haematocrit every two hours during the first six hours and later every four hours until stable.
PLATELET COUNTS
Should be done every 24 hrs

46. SOME TREATMENT PRINCIPLES
HEMATOCRIT RISES + BP FALLING + ↓ URINE OUTPUT
SIGN OF EXTRAVASATION OF FLUID FROM VASCULAR COMPARTMENT
CONSIDER FOR I/V FLUIDS.

47. SOME TREATMENT PRINCIPLES
HEMATOCRIT FALLS + BP FALLING + ↓ URINE OUTPUT
SIGN OF INTERNAL BLEEDING
CONSIDER FOR BLOOD TRANSFUSION.

48. SOME TREATMENT PRINCIPLES
HEMATOCRIT FALLS + BP IMPROVING + ↑ URINE OUTPUT
BACK SHIFT OF FLUID TO VASCULAR COMPARTMENT
WATCH FOR FLUID OVERLOAD

49. SOME TREATMENT PRINCIPLES20 10
7 5 3

50. TRIAGE OF DENGUE PATIENTS
SEND BACK HOME: NO DHF/ DSS
PLATELET COUNT > 1 LACKS
BP NORMAL
OBSERVATION : ANY SIGNS OF DHF
↓ PLATELETS
↓ TLC
HCT ↑ > 10 %
MILD SIGNS OF PLASMA LEAKAGE

51. Indications for admission are –
rise in haematrocrit of 20% or more,
a single haematocrit value of ›40%,
platelets count of ≤ 50,000/cmm,
spontaneous haemorrhage,
signs and symptoms of shock,
oliguria and
circum-oral cyanosis.

52. TRIAGE OF DENGUE PATIENTS
WARD : RESTLESSNESS
PLATELET < 50 THOUSAND
RESTLESSNESS/ DROWSY
PULSE LOW , BP↓
ICU : COMPLICATIONS
SIGNS OF MASSIVE BLEEDING
DSS

53. TREATMENT : DENGUE FEVER & DHF
Febrile Phase
In the early febrile phase, it is not possible to distinguish DF from DHF.
Their treatments are the same, i.e. symptomatic and supportive:
Ø Rest.
Ø Paracetamol
Ø Do not give antibiotics as these do not help.
Ø Oral rehydration therapy
Ø Food should be given according to appetite.

54. TREATMENT : DENGUE FEVER & DHF
Points To Remember:
Ø Paracetamol : not more than 4 times in 24 hours
Do not give Aspirin or Brufen / NSAIDS.
Fear of :
gastritis / bleeding.
Reye’s syndrome (encephalopathy) , In children,

55. TREATMENT : DENGUE FEVER & DHF
Points To Remember:
Ø Oral rehydration therapy
In Children
oral rehydration solution or fresh juices are preferable
(50ml/kg bodyweight - during the first 4-6 hrs. + maintenance fluids. )
Breastfeeding should be continued
In adults
Oral fluid intake of litres should be given per day.)

56. DENGUE FEVER : DANGER SIGNS
Severe Abdominal Pain,
Passage Of Black Stools,
Bleeding Into The Skin Or From The Nose Or Gums,
Sweating
Cold Skin
All dengue patients must be carefully observed for
complications for at least 2 days after recovery from fever.
Patient who has no complication and who is afebrile for last 2-3 days does not need further observation.

57. TREATMENT OF AFEBRILE/ CRITICAL STAGE
Afebrile Phase : 2-3 days after febrile illness
Dengue Fever:
Most patients will recover without complication.
Bed rest
Check platelets/haematocrit
Oral fluids and electrolyte Therapy
Convalescence Phase
Further improvement in the condition.
Duration – 7-10 days after critical Stage

58. TREATMENT OF AFEBRILE/ CRITICAL STAGE
Dengue Haemorrhagic Fever Grades I
Do not usually require intravenous fluid therapy
ORT is sufficient.
Intravenous fluid therapy may needed:
Vomiting persistently or severely,
Refusing to accept oral fluids.
Patients with DHF grade I who live far away from the hospital or those who are not likely to be able to follow the medical advice should be kept in the hospital for observation.
Intravenous fluid therapy before leakage is not recommended.

59. CHOICE OF FLUID FOR INTRAVENOUS THERAPY
Crystalloid:
5% dextrose in isotonic normal saline solution (5% D/NSS)
(b) 5% dextrose in half-strength normal saline solution (5% D/1/2/NSS)
(c) 5% dextrose in lactated Ringer’s solution (5% D/RL)
(d) 5% dextrose in acetated Ringer’s solution (5% D/RA)
Colloid :
a) Dextran 40
b) Plasma

60. DENGUE : FLUID REPLACEMENT
The volume of fluid replacement should be just sufficient to
maintain effective circulation during the period of plasma leakage.
Excessive fluid replacement and continuation for a longer
period after cessation of leakage will cause respiratory distress from massive pleural effusion, ascites, and pulmonary congestion / oedema.

61. 3ml/kg/hr; 6ml/kg/hr; 10ml/kg/hr, and 20ml/kg/hr.
DENGUE : FLUID REPLACEMENT
For intravenous fluid therapy of patients with DHF, four regimens of flow of fluid are suggested.:
3ml/kg/hr; 6ml/kg/hr; 10ml/kg/hr, and 20ml/kg/hr.

62. DENGUE : FLUID REPLACEMENT
In general, the volume required is maintenance plus 5-8% deficit.

63. DENGUE : PLATELET THERAPY
Bleeding during DHF may occur due to number of factors such as thrombocytopenia, coagulopathy, vasculopathy.
The main risk factor for severe bleeding in DSS was longer duration of shock.
Thrombocytopenia and coagulopathy were not predictive of bleeding.
The prevention of hemorrhage in DHF/ DSS should be directed at early recognition of shock and its prompt correction rather than transfusions of PC and FFP.

64. DENGUE : PLATELET THERAPY
Platelet should be considered :
<20,000/ cumm
20,000 – 40,000 with bleeding
(Asian journal of transfusion science january 2007)
No difference in the frequency of bleeding was observed comparing patients who received or those who did not receive a platelet
transfusion (even in those with a platelet count < 25,000/ml).
(Dengue bulletin volume 27, 2003)

65. DENGUE : PLATELET THERAPY
One retrospective paediatric intensive care study showed no benefit in prophylactic platelet transfusion for thrombocytopenia <30,000/uL.
(European society of Clinical Microbiology and Infectious Diseases Barcelona, Spain, April 2008)

66. ALWAYS REMEMBER: Cases of DHF should be observed every hour.
Serial platelet and haematocrit determinations, are essential for early diagnosis of DHF.
Timely intravenous therapy – can prevent shock and/or lessen its severity.
If the patient’s 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.

67. ALWAYS REMEMBER:
If improvement occurs, reduce the speed from 20 ml to 10 ml, then to 7 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.
In case of shock, give oxygen.
For correction of acidosis (sign: deep breathing), use sodium
bicarbonate

68. DONT’S Do not give Aspirin or Brufen/ NSAIDS.
Do not give blood transfusion unless indicated, reduction in
haematocrit or severe bleeding along with deterioration of vitals.
Do not use steroid

69. DONT’S Antibiotics are of no use
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.

70. DENGUE : SIGNS OF RECOVERY
Stable pulse, blood pressure and breathing rate
Normal temperature
No evidence of external or internal bleeding
Return of appetite

71. DENGUE : SIGNS OF RECOVERY
No vomiting
Good urinary output
Stable haematocrit
Convalescent confluent petechiae rash

72. CRITERIA FOR DISCHARGING PATIENTS
Absence of fever for at least 24 hours without the use of anti-fever therapy
Return of appetite
Visible clinical improvement
Good urine output
Minimum of three days after recovery from shock
No respiratory distress from pleural effusion and no ascites
Platelet count of more than 50,000/mm3

73. PREVENTION • Preventing breeding of Aedes mosquitoes
• Protection from Aedes mosquitoes’ bites.

74. THANKS