1) Dengue fever is a mosquito-borne tropical disease caused by the dengue virus and spread by several species of mosquito, principally Aedes aegypti. 2) Infection with one dengue virus type usually gives lifelong immunity to that type but only short-term immunity to others, and subsequent infection with a different type increases the risk of severe complications. 3) Aedes aegypti and Aedes albopictus are the two most prominent mosquito species that transmit viruses causing dengue fever, yellow fever, West Nile fever, chikungunya, eastern equine encephalitis, and Zika virus.

1. Dengue fever
BY:
Dr, WALAA SALAH MANAA
SPECIALEST OF PEDIATRIC & FEVER
‫ـيخ‬‫ش‬‫ال‬‫ـفر‬‫ك‬ ‫ـيات‬‫م‬‫ح‬‫ـستشفى‬‫م‬

2. Dengue fever is a mosquito-borne tropical
disease caused by the dengue virus
Dengue is spread by several species of mosquito of
the Aedes type, principally A. aegypti. The virus has
five different types; infection with one type usually
gives lifelong immunity to that type, but only short-
term immunity to the others.
Subsequent infection with a different type increases
the risk of severe complications

3. About half a million people require admission to
hospital a year.
(NSAIDs) such as ibuprofen should not be
used
Dengue has become a global problem since
the Second World War and is common in more than
110 countries
Each year between 50 and 528 million people are
infected and approximately 10,000 to 20,000 die
The earliest descriptions of an outbreak date from
1779.

4. Dengue fever virus (DENV) is an RNA virus of the
family Flaviviridae; genus Flavivirus.
Other members of the same genus include yellow fever
virus, West Nile virus, St. Louis encephalitis
virus, Japanese encephalitis virus, tick-borne encephalitis
virus, Kyasanur forest disease virus, and Omsk
hemorrhagic fever virus.
Most are transmitted by arthropods (mosquitoes
or ticks), and are therefore also referred to
as arboviruses(arthropod-borne viruses).
Virology

5. There are 5 serotypes, of which the first four are
referred to as DENV-1, DENV-2, DENV-3 and DENV-4.
The fifth type was announced in 2013.
one serotype is thought to produce lifelong immunity to that
type, but only short-term protection against the other three.
The risk of severe disease from secondary infection increases
if someone previously exposed to other serotype

6. Fact 1: Females Are the Ones that Bite and Transmit Disease
Fact 2: Aedes aegypti Strike During the Day
Fact 3: Aedes aegypti are Becoming Resistant to
Insecticides
Fact 4: Aedes aegypti Love Your Home Just as Much
as You Do
Fact 5: Aedes aegypti are Highly Invasive
Five Facts You Need to Know about Aedes aegypti
July 14, 2016

7. Other Aedesspecies that transmit the
disease include
A. albopictus,
A. polynesiensis
A. scutellaris.

8. 25 Facts about Aedes aegypti

10. 1-‫التواجد‬ ‫أماكن‬
‫خزانات‬ ‫مثل‬ ‫طويلة‬ ‫لفترات‬ ‫النظيف‬ ‫المياه‬ ‫تخزين‬ ‫أماكن‬ ‫في‬ ‫توجد‬
‫المياه‬
2-‫الحياة‬ ‫دورة‬
‫شقين‬ ‫إلى‬ ‫حياتها‬ ‫دورة‬ ‫تنقسم‬:‫ش‬ ‫على‬ ‫الماء‬ ‫في‬‫كل‬
‫الطائرة‬ ‫البعوضة‬ ‫وهي‬ ‫اليابسة‬ ‫وعلى‬ ‫يرقة‬
3-‫النمو‬ ‫مراحل‬
‫ب‬ ‫لبعوضة‬ ‫تحولها‬ ‫قبل‬ ‫مرات‬ ‫أربع‬ ‫اليرقة‬ ‫تنسلخ‬‫الغة‬
‫طائرة‬
4-‫التزواج‬ ‫موسم‬
‫األو‬ ‫اليوم‬ ‫في‬ ‫التزاوج‬ ‫موسم‬ ‫البعوضة‬ ‫تبدأ‬‫بعد‬ ‫ل‬
‫طائرة‬ ‫بعوضة‬ ‫إلى‬ ‫تحولها‬
5-‫التزاوج‬ ‫كيفية‬
‫وتح‬ ‫واحدة‬ ‫مرة‬ ‫واإلناث‬ ‫الذكور‬ ‫بين‬ ‫التزاوج‬ ‫يحدث‬‫تفظ‬
‫المنوية‬ ‫الحافظة‬ ‫في‬ ‫المنوي‬ ‫بالسائل‬ ‫األنثى‬

11. 6-‫الذكر‬ ‫دور‬
‫التزاوج‬ ‫بمجرد‬ ‫البيولوجية‬ ‫وظيفته‬ ‫النتهاء‬ ‫جدا‬ ‫قصيرة‬ ‫الذكور‬ ‫حياة‬ ‫مدة‬
7-‫مؤذيا‬ ‫ليس‬ ‫الذكر‬
‫األزهار‬ ‫رحيق‬ ‫على‬ ‫ويتغذى‬ ‫بالبشر‬ ‫يحتك‬ ‫ال‬ ‫الذكر‬
‫أذى‬ ‫دون‬ ‫المنازل‬ ‫داخل‬ ‫يتواجد‬ ‫وأحيانا‬
8-‫األنثى‬ ‫دور‬
‫ب‬ ‫ومجهزة‬ ‫بالبشر‬ ‫تحتك‬ ‫المصرية‬ ‫البعوضة‬ ‫أنثى‬‫أدوات‬
‫اللدغ‬
9-‫األنثى‬ ‫فم‬
‫م‬ ‫على‬ ‫يحتوي‬ ‫ولعابها‬ ‫الجلد‬ ‫لثقب‬ ‫مجهز‬ ‫األنثى‬ ‫فم‬‫واد‬
‫القرص‬ ‫مكان‬ ‫محمرا‬ ‫ورما‬ ‫وتسبب‬ ‫الدم‬ ‫تهيج‬ ‫كيمائية‬

12. 10-‫للدغ‬ ‫المعرضة‬ ‫المناطق‬
‫أنثى‬ ‫تلدغ‬«‫اآليديس‬»‫ا‬ ‫من‬ ‫السفلية‬ ‫المناطق‬ ‫في‬‫لجسد‬
‫القدم‬ ‫مثل‬
11-‫اللدغ‬ ‫فترات‬
‫أنثى‬ ‫تلدغ‬«‫اآليديس‬»‫ب‬ ‫ما‬ ‫الصباحية‬ ‫الفترة‬ ‫في‬‫ين‬7
‫إلى‬10‫صباحا‬
12-‫البيض‬ ‫وضع‬ ‫قبل‬
‫الد‬ ‫من‬ ‫وجبة‬ ‫عن‬ ‫األنثى‬ ‫تبحث‬ ،‫البيض‬ ‫وضع‬ ‫قبل‬‫ماء‬
‫البشرية‬
13-‫م‬‫البيض‬ ‫تضع‬ ‫تى‬
‫اإلنسان‬ ‫دم‬ ‫على‬ ‫تغذيها‬ ‫بعد‬ ‫بيضها‬ ‫األنثى‬ ‫تضع‬
‫أيام‬ ‫ثالثة‬ ‫أو‬ ‫بيومين‬
14-‫ع‬‫البيض‬ ‫دد‬
‫بين‬ ‫ما‬ ‫األنثى‬ ‫تضع‬150‫إلى‬300‫الواحدة‬ ‫المرة‬ ‫في‬ ‫بيضة‬

13. 15-‫تبيض‬ ‫مرة‬ ‫كم‬
‫من‬ ‫األنثى‬ ‫تبيض‬3‫إلى‬5‫حياتها‬ ‫دورة‬ ‫في‬ ‫مرات‬
16-‫ع‬‫األنثى‬ ‫مر‬
‫بين‬ ‫ما‬ ‫المصرية‬ ‫البعوضة‬ ‫أنثى‬ ‫عمر‬20‫إلى‬30‫يوما‬
17-‫البيض‬ ‫يفقس‬ ‫متى‬
‫من‬ ‫البيض‬ ‫يفقس‬8‫إلى‬ ‫أيام‬30‫الحرارة‬ ‫ودرجة‬ ‫يوما‬
‫المدة‬ ‫في‬ ‫تتحكم‬ ‫التي‬ ‫هي‬
18-‫البيض‬ ‫يفسد‬ ‫متى‬
‫وتنش‬ ‫الشديدة‬ ‫البرودة‬ ‫فترة‬ ‫في‬ ‫البيض‬ ‫يفسد‬‫دورة‬ ‫ط‬
‫والخريف‬ ‫الربيع‬ ‫في‬ ‫البعوضة‬ ‫حياة‬

14. 19-‫تواجدها‬ ‫كثافة‬
‫األ‬ ‫بنقل‬ ‫يسمح‬ ‫ال‬ ‫بسيطة‬ ‫بأعداد‬ ‫البعوضة‬ ‫تواجد‬‫مراض‬
20-‫أ‬‫تواجدها‬ ‫ماكن‬
‫بينهم‬ ‫ومن‬ ‫البلدان‬ ‫من‬ ‫عددا‬ ‫المصرية‬ ‫البعوضة‬ ‫تستوطن‬
‫بكثافة‬ ‫السعودية‬
21-‫لمصر‬ ‫البعوضة‬ ‫دخول‬
‫بيض‬ ‫شكل‬ ‫على‬ ‫مصر‬ ‫إلى‬ ‫البعوضة‬ ‫دخول‬ ‫الممكن‬ ‫من‬
‫الجفاف‬ ‫يتحمل‬ ‫وأنه‬ ‫خاصة‬
22-‫انتقالها‬ ‫كيفية‬
‫تستطيع‬ ‫وال‬ ‫الطيران‬ ‫طريق‬ ‫عن‬ ‫البعوضة‬ ‫تنتقل‬
‫من‬ ‫أكثر‬ ‫الطيران‬3‫كيلومترات‬

15. 23-‫البعوض‬ ‫أنواع‬
‫قرابة‬ ‫يوجد‬80‫جميعهم‬ ‫بالضرورة‬ ‫ليس‬ ‫البعوض‬ ‫من‬ ‫نوعا‬
‫معين‬ ‫لمرض‬ ‫مخصصة‬ ‫بعوضة‬ ‫وكل‬ ‫األمراض‬ ‫ينقل‬
24-‫م‬‫البعوض‬ ‫من‬ ‫تتخلص‬ ‫صر‬
‫بعوض‬ ‫من‬ ‫تخلصت‬ ‫مصر‬«‫اآليديس‬»‫خمسينات‬ ‫في‬
‫العشرين‬ ‫القرن‬‫الصفراء‬ ‫الحمى‬ ‫نقل‬ ‫في‬ ‫لتسببها‬
25-‫التسمية‬ ‫سبب‬
‫بعوضة‬ ‫تسمية‬ ‫تم‬«‫اآليديس‬»‫الكتش‬ ‫بالمصرية‬‫افها‬
‫مصر‬ ‫في‬ ‫مرة‬ ‫أول‬

18. The two most prominent
species that transmit
viruses are Aedes
aegypti and Aedes
albopictus which transmit
the viruses that cause
1-dengue fever,
2-yellow fever
3-West Nile fever
4-chikungunya,
5-eastern equine encephalitis, and
6-Zika virus
along with many other, less notable diseases.
Infections with these viruses are typically
accompanied by a fever, and, in some cases,
encephalitis, which can lead to death.

24. transmitted via infected blood products through organ donation.
In countries such as Singapore, where dengue is endemic, the risk
is estimated to be between 1.6 and 6 per 10,000 transfusions.
Vertical transmission during pregnancy or at birth has been
reported.
person-to-person modes of transmission have also been reported,
but are very unusual.
Dengue can also be

25. pathogenesis of dengue

26. why secondary infection with a different
strain of dengue virus places people at risk
of dengue hemorrhagic fever and dengue
shock syndrome.
The most widely accepted hypothesis is
that of
antibody-dependent enhancement

30. Signs and symptoms

32. asymptomatic
(80%) or have only mild symptoms such as an uncomplicated
fever.
Others have more severe illness (5%)
and in a small proportion it is life-threatening
incubation period
ranges from 3 to 14 days, but most often it is 4 to 7 days.

33. Therefore, travelers returning from endemic areas are
unlikely to have dengue if fever or other symptoms start
more than 14 days after arriving home.

34. Children often experience symptoms similar to those
of the common cold and gastroenteritis (vomiting and
diarrhea)
and have a greater risk of severe complications,
though initial symptoms are generally mild but
include high fever.

36. The characteristic symptoms of dengue are
sudden-onset fever, headache ,
retro orbital pain,
muscle and joint pains, and a rash.
The alternative name for dengue, "breakbone
fever", comes from the associated muscle and
joint pains
The course of infection is divided into three
phases: febrile, critical, and recovery

37. 1- febrile phase
high fever, potentially over 40 °C, and is
associated with generalized pain and a
headache; this usually lasts 2-7days
Nausea and vomiting may also occur.
The fever itself is classically biphasic or
saddleback in nature, breaking and then
returning for one or two days.

38. A rash occurs in 50–80% of those with symptoms
In the first or second day of symptoms as flushed skin, or
later in the course of illness (days 4–7), as a measles-like
rash.
Some petechiae can appear at this point,as may some mild
bleeding from the the mouth and nose

40. Warning signs typically occur
before the onset of severe
dengue.
A probable diagnosis is based on the findings
of fever plus 2 of the following:
nausea and vomiting, rash, generalized
pains, low white blood cell count,
positive tourniquet test, or any warning sign
1-Worsening of abdominal pain
2-persistent vomiting.
3- hepatomegally.
4-mucosl bleeding.
5-high hematocrit low platelets
6-serosal effusion.

41. is present if pulse pressure drops to ≤ 20 mm Hg
along with peripheral vascular collapse.
Peripheral vascular collapse is determined in
children via delayed capillary refill, rapid heart rate,
or cold extremities.
warning signs are an important aspect for early
detection of potential serious disease.
Dengue shock syndrome

42. Grades III and IV are referred to as
"dengue shock syndrome
Dengue hemorrhagic
fever was subdivided
further into
Grade I is the presence only of easy bruising or a positive
tourniquet test in someone with fever,
grade II is the presence of spontaneous bleeding into the
skin and elsewhere,
grade III is the clinical evidence of shock
and grade IV is shock so severe that blood pressure
and pulse cannot be detected.

43. In some people, the disease proceeds to a critical phase as fever
resolves.
During this period, there is leakage of plasma from the blood
vessels, typically lasting 1-2 days.
This may result in ascitis and pleural effusion
as well as depletion of fluid from the circulation and decreased
blood supply to vital organs
There may also be organ dysfunction and severe bleeding,
2-critical phase

44. Shock (dengue shock syndrome) and hemorrhage
(dengue hemorrhagic fever) occur in less than 5%
of all cases of dengue,
however those who have previously been infected
with other serotypes of dengue virus ("secondary
infection") are at an increased risk.
This critical phase, while rare, occurs relatively
more commonly in children and young adults.

45. 3-The recovery phase
The recovery phase occurs next, with resorption of the leaked fluid into
the bloodstream. This usually 2-3 days.
The improvement is often striking, and can be accompanied with
severe itching and a slow heart rate.
Another rash may occur with either a maculopapular or a vasculitic
appearance, which is followed by peeling of the skin.
During this stage, a fluid overload state may occur; if it affects the brain,
it may cause a reduced level of consciousness or seizures.
A feeling of fatigue may last for weeks in adults.

46. The rash that commonly forms during the
recovery from dengue fever with its classic
islands of white in a sea of red.

47. 1-A decreased level of consciousness occurs in 0.5–6% of severe
cases, which is due to either
viral encephalitis or indirectly as a result of impairment of vital
organs, for example, the liver.
2-CNS disorders have been reported, such as transverse
myelitis and Guillain–Barré syndrome,
3- acute liver failure are among the rarer complications.
4-A pregnant woman who develops dengue may be at a higher
risk of abortion as well as LBW and premature birth.
Associated problems

48. risk factors for severe disease
1-babies and young children
2-female,
3-high body mass index,
3- high viral load.
4-chronic diseases such as diabetes and asthma]

51. laboratory investigations
Leucopenia ,thrompocytopenia and metabolic acidosis
moderately elevated level of (AST and ALT) from the liver is common.
In severe disease, plasma leakage results
in hemoconcentration (rising hematocrit) and hypoalbuminemia.
Pleural effusions or ascites can be detected by physical examination when
large, but the demonstration of fluid on ultrasound may assist in the early
identification of dengue shock syndrome.
virus isolation in cell cultures, PCR

52. Why CT brain ?

56. There are no specific antiviral drugs for dengue,
however maintaining proper fluid balance is important
Treatment depends on the symptoms.
Those who are able to drink, are passing urine, have no
"warning signs" and are otherwise healthy can be managed
at home with daily follow up and oral rehydration therapy
Those who have other health problems, have "warning
signs", or who cannot manage regular follow-up should be
cared for in hospital.[
In those with severe dengue care should be provided in an
area where there is access to an intensive care unit

57. IV fluid, if required, is typically only needed for1-2
days.
In children with shock due to dengue a rapid dose of
20mL/kg is reasonable.
The rate of fluid administration is than titrated to
a urinary output of 0.5–1 mL/kg/h, stable vital
signs and normalization of hematocrit.
The smallest amount of fluid required to achieve this
is recommended

58. Invasive medical procedures
such as nasogastric
intubation, intramuscular
injections and arterial
punctures are avoided, in
view of the bleeding risk.[
Paracetamol is used for
fever and discomfort
while NSAIDs such
as ibuprofen and aspirin are
avoided as they might
aggravate the risk of
bleeding

59. Dengue fever – do not give Aspirin or
Ibuprofen to the patient
The infecting organism in dengue affects the
platelets which are responsible for clotting (stopping
bleeding) increasing the tendency of the person to
bleed.
Aspirin and Ibuprofen also have similar action. Both
of them together could cause the person to bleed
excessively pushing the patient into what is called
the ‘Dengue Shock syndrome’.
And once in this stage, medical treatment is needed
in an emergency basis and hospitalization becomes
necessary.

60. Blood transfusion is initiated early in
people presenting with unstable vital
signs in the face of a decreasing
hematocrit.[
Packed red blood cells or whole
blood are recommended,
while platelets and fresh frozen
plasma are usually not.
There is not enough evidence to
determine if corticosteroids have a
positive or negative effect in dengue
fever

61. During the recovery phase intravenous fluids
are discontinued to prevent a fluid
overload.
If fluid overload occurs and vital signs are
stable, stopping further fluid may be all that
is needed.
If a person is outside of the critical phase,
a loop diuretic such as furosemide may be
used to eliminate excess fluid from the
circulation.]

62. Prevention

63. Vaccine
In 2016 a partially effective vaccine for dengue
fever became commercially available