4. What is dengue fever?
Dengue Fever is an illness caused by
infection with a virus transmitted by the
Aedes mosquito.
The word dengue is derived from
African word denga: meaning fever
with hemorrhage .
6. …and become a MAJOR pandemic in
the last 50 years
Endemic in more than 1oo
countries
2.5 billion people at
risk
www.tatterhood.com/category/gameart/tastyplanet
11. 992- Chinese Encyclopedia
1780- Philadelphia “break-bone
fever”
Benjamin Rush
Dengue Fever has a long history…
www.philadelphia-reflections.com/topic/17.htm
12. 12
Dengue/DHF in the History
First epidemic- French West Indies in 1635
Outbreak of similar disease in China 992 A.D
During 18th, 19th and 20th century Dengue-like
disease outbreak in SEA
RUSH, B described “Break-bone Fever” in
Philadelphia during 1780
Suspected DHF outbreak
Australia-1897;
Greece-1928 and
Taiwan-1931;
*confirmed outbreak in Philippines in 1953.
14. Dengue: Concerns
In a geographical territory
• Dengue Enters
• Dengue never Exits
• Cyclical outbreaks
History &
Evidence
reveals
that
Theme is: Learn to live with Dengue
14
15. Dengue Facts-1
Arbo-viral disease
Virus-Genus: Flavivirus
Four serotypes: Den 1, Den 2, Den 3, Den 4. Infection
with one serotype confers life long immunity to that
serotype and cross immunity to other serotypes for 2-3
months only.
All four serotypes are associated with epidemic and
DHF.
16. Dengue Facts-2
Aedes mosquitoes transmit dengue from person to
person
25 species of Aedes are recorded globally
Incriminated vectors are Ae. aegypti, Ae. albopictus,
Ae. polynesiensis and Ae.niveus (In Bangladesh only
Ae. aegypti)
Ae. aegypti – most important epidemic (primary)
vector.
17. The most common epidemic vector of dengue in the
world is the Aedes aegypti mosquito. It can be
identified by the white bands or scale patterns on its
legs and thorax.
18. Dengue Transmission
Female Aedes aegypti is the principal vector (Aedes albopictus
is suspected vector)
Extrinsic incubation period 8-10 days
Infective mosquito transmit dengue through salivary fluid to
a susceptible person
Intrinsic incubation period 3-14 days (4-6 days average)
19. Dengue Transmission
Viraemia starts 1-2 days before clinical symptoms and lasts
for another 5 days
This is crucial period as the patient is most infective
Trans-ovarian or vertical transmission occur in several
species – important for virus maintenance but not
important for epidemic
Can infect several members of the family by interrupted
feeding.
20. Habits of Aedes aegypti
Breeding habit:
It breeds almost entire in domestic man made
water receptacles or artificial breeding sources
The common breeding sources: Plastic pots,
water storage jars, Food containers, flower
vases, cement baths, unused tyres, bottles, tin
cans, over head tanks(open), discarded wet cell
batteries, ant traps, freeze, A/C etc.
21. Habits of Aedes Aegypti
Feeding habit:
Two periods of biting, in the morning and in the
afternoon
May feed on more than 1 person in interrupted
feeding- can infect several members of a family
if the mosquito is infective
Generally does not feed at night but may feed in
well lighted rooms at night.
22. Habits of Aedes aegypti
Resting habit:
Prefer to rest in dark, humid, secluded places inside
houses
Preferred indoor resting places are the underside of
furniture, hanging cloths, curtains and other articles.
33. 1.The virus is inoculated
into humans with the
mosquito saliva.
2.The virus localizes and
replicates in various
target organs, for
example, local lymph
nodes and the liver.
3.The virus is then
released from these
tissues and spreads
through the blood to
infect white blood cells
and other lymphatic
tissues.
4.The virus is then
released from these
tissues and circulates in
the blood.
Dengue Transmission
Cycle
34. 5.The mosquito ingests blood containing the virus.
6.The virus replicates in the mosquito midgut, the
ovaries, nerve tissue and fat body. It then escapes
into the body cavity, and later infects the salivary
glands.
7.The virus replicates in the salivary glands and
when the mosquito bites another human, the cycle
continues.
35. 35
Causative agent of Dengue
Dengue is caused by a RNA virus
Dengue virus
Bauman, R., (2006). Microbiology disease by systems. San Francisco , CA: Pearson Benjamin Cumming
Publishers
36. Virology
Flavivirus family
Small enveloped viruses
containing single stranded
positive RNA
Four distinct viral
serotypes (Den-1, Den-2,
Den-3, Den-4)
37. Dengue virion are spherical particles approximately 50 nm in
diameter.
contains a single plus strand of RNA. Surrounded by a lipid
bilayer.
Because of the lipid envelope, flavviviruses are readily inactivated
by organic solvents and detergents.
39. Bangladesh
• Cases are reported from
Dhaka and other Metropolitan
cities, mainly;
• Aedes mosquito are mainly
indoor biter and breed in
artificial containers;
• Community awareness for
Aedes control is the key
intervention;
• Proper Clinical management
can reduce deaths;
• Dengue control is a multi-
sectoral collaboration and not
only, HEALTH Dept.;
39
40. 40
Dengue Outbreak in Bangladesh
First outbreak of dengue fever (Dhaka fever)
was documented in 1964 in Dhaka followed
by few
Scattered cases of DF during 1977-78
In 1996-97 dengue infections were
confirmed in 13.7% of 255 fever patients
screened at Chittagong Medical College
41. Dengue SERO-SURVEY-1996-97
• Study site: CMC Hospital
• Lab: IEDCR, DGHS
• Sponsor: ICOVED, DGHS
• Collab. lab: AFRIMS, Bangkok,
Thailand
Sero-Survey findings
• 13.7% of <15 yrs children
attending OPD with fever are
sero-positive ;
• Sub-types: DEN 2; 3;4 (No DEN-
1)
*Subsequent Ento-survey by
Bruce
Knudsen predicted the
Outbreak Potential
Dengue/DHF
in BANGLADESH
41
42. No other disease got such
attention
Panic situation
• People
• Professional
• Media
• Posters –Blood
Test… labs.
• Blaming!!
First Outbreak in 2000
42
43. Courtesy: The Daily Star
"Imagination is more important than knowledge." - Einstein
The People and Profession
in Bangladesh have been
developing the knowledge,
skill and attitude to tackle
the ‘Dengue Menace’
A national daily reporting
an ingenuity effort to face
dengue
July 2000
43
44. Dengue Outbreak
The reemergence started in 2000 with 5551 cases and
93 death
The worst outbreak was in 2002 with 6,104 cases and
58 deaths.
45. 45
Monthly Distribution of Dengue Cases and Deaths
0 0 0 0 0 0
29
189
115
76
0 00 0 0 0 0 0 0 0 0 0 0 00
20
40
60
80
100
120
140
160
180
200
JanuaryFebruary
M
arch
April
M
ay
June
July
AugustSeptem
berOctoberNovem
berDecem
ber
Months
cases
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
deaths
Cases
Deaths
51. Dengue
Acute viral infection- main vector is Aedes aegypti
4 serotypes, antigenically cross-reactive
Infection with 1 serotype confers life-long immunity to that
serotype, but elicit cross protection for only few months to other
A second infection with a different serotype is associated with
enhanced risk for severe disease
No animal models of disease, no licensed vaccines or anti-viral drugs
Sylvatic cycleUrban cycle
52. Pathogenesis of Dengue Syndrome
Dengue virus, which has 4 distinct serotypes, i.e. DEN-I,
DEN-II, DEN-III, DEN-IV is transmitted by Aedes aegypti and
Aedes albopictus to human.
Uninfected mosquitoes acquire the virus when they feed on a
viremic individual.
The virus develops in the mosquito within 1 to 2 weeks and
once it reaches the salivary glands, it can be transmitted to
humans during feeding attempts
53. Pathophysiology
After an infective mosquito bite in subcutaneous or
intradermal space, the virus replicates locally at the site of
inoculation, in cells of reticuloedothelial system or fibroblast
or both.
Then it is detected in local lymph nodes and within 2 to 3
days, disseminates via blood to various tissues.
The virus circulates in the blood typically for 4 to 5 days
during the febrile phase and is cleared within a day of
defervescence.
Dengue virus can be detected in monocytes, hepatocytes but
not inT cells or endothelial cells.
54. Pathophysiology
Primary dengue infection develops serum antibodies that can
neutralize the homologous serotype.
In a secondary infection, the pre-existing heterologous antibodies
form complexes with the new infecting virus serotype, but do
not neutralize the new virus.
Secondary infections have been shown to lead to higher viral
loads and the manifestations of severe dengue are believed to be
due to virus replication which induces infected monocytes to
release vasoactive mediators.
Excessive release of vasoactive mediators results in increased
vascular permeability and hemorrhagic manifestations that
characterizes DHF and DSS.
55. Pathophysiology and cytokine
The pathogenesis of severe disease is not well understood.Various
mechanisms of severe disease have been suggested, including:
(a) Antibody-dependent enhancement or ADE,
(b) Complement activation by virus-antibody complexes and
(c)T-cell mediated immunopathology
(d) Cytokine abundance.
Dengue infected monocytes act as antigen presenting cells (APCs) to
induce release of lymphokines and other factors from activatedT cells.
Tumour Necrosis Factor- α,Interleukin(IL) IL-1β, IL-2, IL-6, IL-8,
Interferon (IFN)-γ, RANTES etc. are the cytokines that are released
from these cells.
These cytokines along with complement breakdown products (C3a,
C5a) activated in DHF/DSS, increases vascular permeability of
vascular endothelial cells leading to DSS.
56. Severe Dengue: immunopathogenesis
Mo
Mo
CD4
CD8
Ab’s Monocytes T cells
Complement Macrophages
IFN
C3a C5a TNF, IL-1, PAF IL-2, TNF, IL-6
IL-6 IFNγ
↑ FcR, MHC I and II
Complement
activation
Capillary leak syndrome ⇒ DHF
Vascular endothelial cells
Lysis
Lysis
Infection
Dengue virus
Capillary leakage
viraemia
IgM
IgG
0 1 2 3 4 5 6
days
Inflammatory
host response
A patient with secondary dengue
64. Clinical Presentations(Dengue
Syndrome)
Majority patients infected with dengue virus remain
asymptomatic.
Others, develop a febrile illness and the manifestations of
which are similar and overlapping .They are grouped into
'Dengue Syndromes' which encompass the following:
Undifferentiated fever
DF
DHF
Expanded dengue syndrome (rare)
65.
66. Case definitions
Case definitions are developed as aid tools for Early
diagnosis and prompt treatment, Epidemiological
Surveillance and reporting.
Purpose:
For uniformity in clinical case management at both
outpatient and inpatient setups.
For uniform reporting of the cases to designated appropriate
health authority.
67. Management:
1.Dengue Fever
2.Dengue Haemorrhagic Fever
3.Dengue Shock Syndrome
4.Expanded dengue syndrome
Case Definitions For Reporting
1.Suspected: Clinically diagnosed as per‘Clinical Case Definition’
2.Probable: Clinical Diagnosis+ Positive serology
3.Confirmed:When case is confirmed byVirus isolation or antigen
detection
68. Revised case classification by
severity
1.Dengue without warning signs (May be send home):GroupA
2.Dengue with warning signs( Referred for in hospital care):GroupB
3.Severe dengue( Require emergency treatment):GroupC
69.
70. Classification of Dengue
Old WHO classification New WHO classification
Classical Dengue Fever Probable dengue ( group A - OPD
management)
Dengue Fever with hemorrhagic
manifestations
Dengue with warning signs ( Group B
- inward observation and
management)
( patients are admitted for social reasons and when
they are in high risk category)
DHF grade one
DHF grade two
DHF grade three Severe Dengue ( Group C – Tertiary
care resuscitation and management)
1.Severe plasma leakage
2.Severe bleeding
3. Severe organ impairment
DHF grade four
DHF with unusual manifestations
72. Natural course of dengue infection
3 Phases
A. Febrile Phase(2-7days)
B. Afebrile/Critical Phase(2-3days)
C. Convalescent/Recovery Phase
(7-10days)
72
75. Dengue Fever
Dengue Fever
Suspected Dengue:
Acute febrile illness of 2 to 7 days duration with 2 or more of the following:
• headache,
• retro-orbital pain,
• myalgia,
• arthralgia/bone pain,
• rash,
• haemorrhagic manifestations( Unusual hemorrhage)
• leucopenia (wbc ≤5000 cells/mm3),
• thrombocytopenia (platelet count <150 000 cells/mm3),
• rising haematocrit (5 – 10%);
And
•High index of suspicion based on Period, Population & Place
And
•Absence of convincing evidence of any other febrile illness
76. Fever
Sudden onset, high grade, continued.
The body temperature is usually between 39 °C and 40 °C
(102° F to 104° F).
The fever may be biphasic, lasting 2–7 days in the majority of
cases.
77. Rash
first 2 to 3 days - Diffuse flushing or fleeting eruptions may be
seen on the face, neck and chest
third and fourth day- a conspicuous rash that may be
maculopapular or rubelliform
afebrile period or defervescence - Some patients have a
confluent erythematous or petechial rash with small areas of
normal skin, described as “islets of white in the sea of red” may
appear over the dorsum of the feet, on the legs and on the hands
and arms. Skin itching may be observed.
78. Probable Dengue:
Suspected dengue and at least one of following:
• supportive serology on single serum sample: IgG titre ≥1280 with
haemagglutination inhibition test/ enzyme-linked immunosorbent assay, or testing
positive in IgM antibody test.
Confirmed dengue:
Probable case with at least one of the following:
• isolation of dengue virus from serum, CSF or autopsy samples.
• fourfold or greater increase in serum IgG (by haemagglutination inhibition test) or
increase in IgM antibody specific to dengue virus in paired sera.
• detection of dengue virus or antigen in tissue, serum or cerebrospinal fluid by
immunohistochemistry, immunofluorescence or enzyme-linked immunosorbent
assay.
• detection of dengue virus genomic sequences by reverse transcription-polymerase
chain reaction.
79. Dengue Haemorrhagic Fever
Suspected DHF:
All of following:
Acute onset of fever of two to seven days duration.
Haemorrhagic manifestations, shown by any of the following:
positive tourniquet test,
petechiae, ecchymoses or purpura, or
bleeding from mucosa, gastrointestinal tract, injection sites, or other locations.
Platelet count ≤100 000 cells/mm3
Objective evidence of plasma leakage due to increased vascular permeability shown by any of
the following:
Rising haematocrit/haemoconcentration ≥20% from baseline or
decrease in convalescence, or
pleural effusion, ascites or
hypoproteinaemia/ albuminaemia.
And
•High index of suspicion based on Period, Population & Place
And
•Absence of convincing evidence of any other febrile illness
80. Dengue Haemorrhagic Fever
Probable DHF:
Suspected dengue and at least one of following:
• supportive serology on single serum sample: IgG titre ≥1280 with
haemagglutination inhibition test/ enzyme-linked immunosorbent assay, or testing
positive in IgM antibody test
Confirmed DHF:
Probable case with at least one of the following:
• isolation of dengue virus from serum, CSF or autopsy samples.
• fourfold or greater increase in serum IgG (by haemagglutination inhibition test) or
increase in IgM antibody specific to dengue virus in paired sera.
• detection of dengue virus or antigen in tissue, serum or cerebrospinal fluid by
immunohistochemistry, immunofluorescence or enzyme-linked immunosorbent
assay.
• detection of dengue virus genomic sequences by reverse transcription-polymerase
chain reaction.
81. Example
A case is found to be Dengue Fever as per clinical case definition.
For reporting purpose clinically defined case will be labeled as
'Suspected Dengue Fever'. If any serological test is found positive
this case will be 'Probable Dengue Fever' and, will be labeled
'Confirmed' when virus is isolated
82. Dengue Shock Syndrome
Criteria for dengue haemorrhagic fever as before with signs of
shock including:
Tachycardia, cool extremities, delayed capillary refill, weak pulse,
lethargy or restlessness, which may be a sign of reduced brain perfusion.
Pulse pressure ≤20 mmHg with increased diastolic pressure, e.g.
100/80 mmHg.
Hypotension by age, defined as systolic pressure <80 mmHg for those
aged <5 years or 80 to 90 mmHg for older children and adults.
84. Expanded dengue syndrome
Unusual manifestations with severe organ involvement
such as liver, kidneys, brain or heart associated with
dengue infection have been increasingly reported in DHF and
also in DF who do not have evidence of plasma leakage.
These unusual manifestations may be associated with
coinfections, comorbidities or complications of
prolonged shock.
Exhaustive investigations should be done in these cases.
87. Severity Grading Of Dengue Syndrome
Syndromes Grad
e
Clinical Features Laboratory features
DF Fever with 2 or more of the following:
•Headache
•Retro-orbital pain
•Myalgia
•Arthralgia/bone pain
•Rash
•Haemorrhagic manifestations
•No evidence of plasma leakage
•Leucopenia (wbc ≤5000
cells/mm3).
• Thrombocytopenia (Platelet
Count <150 000 cells/mm3).
• Rising haematocrit (5% – 10%)
• No evidence of plasma loss.
DHF I Fever and haemorrhagic manifestation
(positive tourniquet test) and
evidence of plasma leakage
•Thrombocytopenia ≤
100,000 /mm3
•Hct rise ≥ 20%
88. Severity Grading of Dengue syndrome(Cont…)
Syndromes Grade Clinical features Laboratory features
DHF ІІ As in Grade I
plus
spontaneous bleeding
•Thrombocytopenia ≤
100,000 /mm3
•Hct rise ≥ 20%
DHF(DSS) ІІІ As in Grade I or II
plus
circulatory failure
(weak pulse, narrow
pulse pressure (≤20
mmHg), hypotension,
restlessness).
•Thrombocytopenia
< 100,000/mm3
•Hct rise ≥ 20%
DHF(DSS) IV As in Grade III
plus
profound shock with
undetectable BP and
pulse
•Thrombocytopenia
< 100,000/mm3
•Hct rise ≥ 20%
91. Severity progression
Warning signs
few hrs
Compensated shock
few hrs
Decompensated shok/Hypotensive shock
few min
Cardiorespiratory collapse and cardiac arrest
97. Early laboratory confirmation of clinical diagnosis
is important because some patients progress
within a short period from mild to severe disease
and sometimes to death. Early intervention may
be life-saving.
97
99. Time and frequency of doing
investigations
Within 3 days - CBC, SGOT, SGPT, NS1antigen
Tests should be done during first consultation to get the baseline
characteristics like Haematocrit and Complete blood count if the patient
presented within 3 days of fever.
Follow up testing may be done on 1st
afebrile day, but should be done
daily once DHF is suspected.
A regular haematocrit is more important for management than the
thrombocytopenia. Even in severe dengue especially with shock) hourly
haematocrit is crucial for management.
Once the platelet count begins to rise and reaches ≥ 50,000/mm3
, daily
lab evaluations may be discontinued.
99
106. 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),
106
107. 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).
107
109. Step II—Diagnosis, assessment
of disease phase and severity
On the basis of evaluations of the history, physical examination
and investigations :
Confirm the diagnosis as dengue syndrome
assess the phase (febrile, critical or recovery)
Presence of warning signs
The hydration and hemodynamic status
Needs for admission and/or referral to emergency
department.
109
110. Step II—Diagnosis, assessment
of disease phase and severity
Hospital Admission Criteria
1. Warning signs
Any of the warning signs if present.
110
112. STEP ΙΙΙ:
1.Disease notification
2.Management
Depending on the clinical manifestations and other
Circumstances:
Patients may be sent home (GroupA): Mild Dengue
Referred for in-hospital management or (Group B):Moderate
Dengue
Require emergency treatment and urgent referral (Group C):
Severe Dengue
112
114. Group- A (Mild Dengue): Send home with
advice
Dengue fever –
1.Without complications like bleeding,hypotension or organ involvement
2.Without evidence of plasma leakage(clinical and laboratory)
3.Without co-morbidities or high risk group patients
4.With near normal blood count and hematocrit
114
115. 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, cocoanut water
Plain water alone may cause electrolyte imbalance.
Take paracetamol (not more than 8tabs (4 Gm) per day for adults and
accordingly in children(10-15mg/kg)
Tepid sponging with lukewarm water or shower with lukewarm water
Look for mosquito breeding places in and around the home and
eliminate them
Avoid all NSAIDS and steroids
WithholdAspirin, clopidogrel & dipyridamole in patients who take for
long term 115
116. Home care for dengue
Approach the hospital early if:
No clinical improvement or worsening of the situation just before
or during the transition to afebrile phase or as the disease
progresses
Bleeding
− red spots or patches on the skin
− bleeding from nose or gums
− vomiting blood
− black-coloured 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
Less or no urine output for 4-6 hours.
116
118. Group-B (Moderate Dengue):
Close monitoring and possible
hospitalization
Dengue fever -
1.With warning sign and symptoms
2.With High risk and co-morbid conditions
3. Social circumstances- living alone, living far from hospital facility
4. Dengue hemorrhagic fever with minor bleeding
5.Increasing hematocrit or rapidly decreasing platelet count
118
120. Social reasons
-Living alone
-Living far from hospital
High risk groups and co-morbid conditions:
-Pregnancy, infancy and old age -Renal failure
-obesity -Chronic hemolytic disease
-DM -Autoimmune disease
-HTN
-Heart failure
120
121. Intravenous Fluid therapy in DHF
during the critical period:
Indications for I/V fluid
When the patient cannot have adequate oral fluid
intake or vomiting
When HCT continues to rise 10%- 20% despite oral
rehydration
Impending shock
121
123. Fluid requirement
The fluid requirement, both oral and intravenous, in critical
phase (48 hours) is calculated as M+5% (maintenance + 5%
deficit).
5% deficit is calculated as 50 ml/kg up to 50kg
Calculations for normal maintenance of intravenous fluid
Infusion:
123
125. *For overweight/obese patients calculate normal
maintenance fluid based on ideal body weight (IBW),
using the
following formula:
Female: 45.5 kg + 0.91(height–152.4) cm
Male: 50.0 kg + 0.91(height–152.4).cm
125
126. Calculation of total fluid quota for the critical period
M (Maintenance) =
100ml/kg for first 10 kg
+50 ml/kg for next 10 kg
+20 ml/kg for balance weight
5% of body weight = 50ml x body weight (kg)
E.g.Body weight 22 kg
(This is the ideal or actual body weight, whichever is smaller)
M = 100 x 10 + 50 x 10 + 20 x 2 =1540 ml
5% = 50 x 22 =1100 ml
M + 5% = 1540 + 1100 =2640 ml
126
127. Example of fluid calculation for a 65 kg person
(maximum body weight for fluid calculation is 50 kg)
- For the 1st 10 kg - 100 ml/kg = 1000 ml
- For the 2nd 10 kg - 50 ml/kg = 500 ml
- From 20 kg and above up to 50 kg -20 ml/kg = 600 ml
- 5% deficit is calculated as 50 ml/kg up to 50 kg = 2500 ml
Therefore the maximum fluid requirement for an average adult for
the entire phase of critical 48 hours is 4600 ml.
If the body weight is less than 50 kg, calculation should be done
according to the ideal body weight or actual body weight whichever is
less.
127
128. The fluid quota is aimed at giving just adequate
amount of fluid without causing fluid overload (to
maintain perfusion to vital organs).
Once the fluid quota is exceeded chances of fluid
overload is high.
All patients will not need the full quota of M+ 5%
fluid and many may need less than this, as the rate,
peak and the duration of leaking are variable from
patient to patient.
128
132. The following fluids are recommended both crystalloids and colloids
Crystalloids
0.9% Nacl (isotonic normal saline solution) (0.9%NS)
0.45% half strength normal saline solution (0.45%NS) (For children)
5% dextrose in lactated Ringer's solution (5%DRL)
5% dextrose in acetated Ringer's solution (5%DRA)
Hartman solution
Colloids
Dextran 40
Hemaceel
Plasma
Blood & Blood Components
Human Albumin
132
133. Duration of IV fluid therapy
The duration of intravenous fluid therapy should not exceed
24 to 48 hours for those with shock.
However, for those patients who do not have shock, the
duration of intravenous fluid therapy may have to be longer
but not more than 60 to 72 hours.This is because the latter
group of patients has just entered the plasma leakage period
while shock patients have experienced a longer duration of
plasma leakage before intravenous therapy is begun.
133
148. Monitoring of Dengue Fever Patients
Feeling of well being
Fever
Pulse pressure, Blood pressure and Heart rate
Vomiting/loose stool and oral intake
Urine output
Blood counts specially HCT
148
149. Complications of Dengue
Fever
Haemorrhagic complications
Fluid overload
Ascites, Pleural effusion, Pulmonary aedema
• Metabolic acidosis and electrolyte imbalance
• Severe shock
• Acute Respiratory Distress Syndrome
• Hyperglycaemia and hypoglycaemia
• Nosocomial infections
• Mycocarditis
• Hepatitis
149
150. Indications for Blood
Transfusions
Overt bleeding ( more than 10% or 6-8ml/kg)
Significant drop of HCT < 40 ( < 45 for males) after fluid
resuscitation
Hypotensive shock + low/normal HCT
Persistent or worsening metabolic acidosis
Refractory shock after fluid 40-60 ml/kg
Dose of whole fresh blood:10 ml/kg/dose at a time.
only 10-15% patients need blood
Circulatory failure with high HCT should be managed
with colloids ( + Lasix if fluid overloaded) before
151. To decide on platelet transfusion
To recognize the beginning of critical
stage -
As a prognostic indicator-
Why do you do platelet counts ?
(Answer this MCQ)
152. To decide on platelet transfusion - X
To recognize the beginning of critical
stage -
As a prognostic indicator-
Why do you do platelet counts ?
153. Indication for platelet
concentrate
It has been observed that there is very limited role of platelet
transfusion. In most of the situation fresh whole blood transfusion is
suffice. However it may be required in some special situation.The
indication of which may be as follows:
-Platelet count ≤ 10000 /mm3
If platelet concentrate is not available fresh whole blood may be
transfused as per guidelines given under DHF management.
153
158. Prevention and control of Dengue
Transmission
No vaccine against virus is available
No specific drug against dengue virus
The only way to prevent and control and control Dengue
transmission is the prevention and control of infective/infectious
vector bite.
How to prevent infective bite
No way to differentiate infective and un-infective vector bite.
No way to differentiate vector and non-vector bite.
May be by keeping dengue viraemic patient under mosquito net
specially during day or in mosquito free house/word to avoid
vector contact
Viraemia starts one or two days before on set of clinical symptoms
an transovarian transmission are there.
Cont’
159. Prevention & control of Dengue
Transmission by vector control
By Chemical method:
By application of insecticides in the form of
residual spray, aerosol spray, fog spray ( Thermal
or cold) and ULV spray (Aerial/vehicle mounted)
By application of insecticides in the form of
larvicides–1% temephos (Abate) granules
Scope is very limited and not judicious in all
situation because of adult resting behaviour and
breeding habits.
160. Prevention & control of Dengue
Transmission by vector control
By biological methods:
By predators( Adult and Larvae)
By larvivorus fish (larva)
By bacteria (larva)
By insect growth regulator (IGR)
The scope is also very limited and not judicious
because of adult resting behaviour and breeding
habit.
161. Prevention & control of Dengue
Transmission by vector control
By physical / Environmental Method:
By modification of environment – permanent in nature but
need carrying maintenance (house with mosquito netting,
Insecticide treated sheet and covering of breeding sources.)
By environmental manipulation – temporary in nature but
needs periodic replenishment (detection and destruction,
cleaning and draining, Personal protection, use of
repellants, use of protective clothes, treating doors and
window’s curtains with insecticides, use of mosquito net at
day time sleeping etc.
162. Integrated Vector Management
Integrated Vector Management (IVM) is a decision making process that
anticipates and prevents vector activity and infestation by several
strategies to achieve long term solutions. Components of IVM may
include education, proper waste management, structural
repair, biological and mechanical control techniques, and
pesticide application.
163. Integrated Vector Management
Larval source reduction is the main tool for vector
control. Effective control requires a concerted
effort among the government agencies, NGOs and
communities.
Community understanding and involvement
remains the key for implementation of preventive
and control activities. The control measures should
be implemented at personal, community and
institutional levels.
164. Household Level Action
Wearing protective clothing such as full sleeved
shirts and full pants during day time
Use of mosquito coils, aerosols, mats etc
Use of mosquito net (preferably insecticide-
treated) even during day time
Use of repellents and creams during the day
Placing tight-fitting screens/wire mesh on doors
and windows
Water in containers (earthen jars, cement tanks,
jerry can, tyre etc.) should not be allowed to be
stored for more than five days
165. Community Lvel Action
Raising awareness regarding community
involvement and participation about prevention
and control of dengue.
Cleaning and covering water storage, keeping
surroundings clean, improving basic sanitation
measures
Promoting use of insecticide treated nets and
curtains
Mobilizing households to cooperate during
spraying / fogging
166. Institutional Level Action
Hospitalized patients should be kept under
mosquito net during febrile phase even during day
time
Cleaning of larval habitats like overhead tanks,
ground water storage tanks, air coolers, planters,
flower pots etc every five days
Carrying out indoor and outdoor space spraying
(fogging, ULV etc.)
Promoting personal protection measures
Notification of fever cases to health authorities
167. 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
6 Tight Glycemic control Not monitoring blood glucose
167
168. Each Patient is a Book
Each Day is a Learning Opportunity
CME has More Relevance
NowThan Ever
Together We Learn Better
169. Questions
If you ask a question,
you are a fool for a minute .
but if you don’t,
you are a fool for life.
So what is dengue fever?
Dengue fever is an illness caused by the dengue virus which is spread by the Aedes mosquito.
...and has become a MAJOR epidemic
Estimated 50 to 100 million cases annually, with several 100,000 cases of the more severe form dengue hemorrhagic fever
Endemic in more than 100 countries
Leading cause of death in children in some Asian countries
Over 2.5 billion people at risk for infection, 2/5 of the world’s population
Case-fatality rate for DHF averages 5 percent and 58,000 deaths have been attributed to dengue in the past 40 years
Dengue Fever has a long history…
Earliest description of dengue-like illness in Chinese medical encyclopedia (992)
Outbreak in the west indies in 1635 and Panama in 1699
Epidemic of “break-bone fever” in 1780
Documented that mosquitoes could transmit dengue fever in 1903
Albert Sabin isolates the dengue virus in 1944
The infectious agent of dengue is a virus that belongs to the Flaviviriridae family.
Ab’s from immune complexes which enhance viral infection of monocytes/macrophages. Ab-Ag complexes also activate complment reulting in the generation of C3a and C5a
DV specific T cells are stimulated and secret cytokines, including IFN which up-regulate FcgammaR expression and further augments ADE of infection. IFN also up-regulates MHC class I and class II expression . Increase in the number of DV infected monocytes expressing increased levels of MHC class I and II molecules which facilitates the activation of DV specific T cells which respond with further cytokine productionIFN activated macrophages secrete pro-inflammatory cytoikines (e.g. TNF) on infection with DV or DV infected macrophages release high levels of pr-inflammatory cytokines and other inflammatory mediators as a result of lysis by virus specific CD4+ and/or CD8+ T cells. Finally, platelet activating factor is released from a variety of cells including platelets, monocytes and endothelial cell.
End result is increase in inflammatory mediators which results in malfunctionof vascular endothelial cell, plasma leakage, shock and derangement of coagulation system