Dengue images

Dengue
(Fièvre dengue, Dengue Fever, DF)
résumée en 3 images
DF virus isolation in cell culture
….
4 virus dengue responsables : DEN-1 à DEN-4
avec immunité croisée incomplète
Copyright CDC
La FD est une maladie épidémique
DF est une maladie épidémique saisonnière
DHF: une mal. émergente qu’on soigne de mieux en mieux
Cas de DHF reportés au Vietnam de 1963 à 1998
Dengue Thailand
DF: la mortalité globale est faible, < 2%
DF : mortalité globale faible (Thaïlande)
La DF est une maladie émergente
(ou en progression épidémique)
N° cas annuels DHF Thailande - Indonesie - Vietnam
Copyright CDC
DF maladie épidémique urbaine (Bangkok)
DF :une maladie émergente (Brésil)
Dengue Brésil : âge de survenue
Aedes aegypti: le principal vecteur
Aedès : le moustique à pattes tigrées
pique en fin de journée
www.fiocruz.br/ccs/ estetica/dengue.htm.
Géographie de DF et Aedes aegypti
Année 2000
Dengue : répartition géographique
Cycle de la
dengue :
- tropical
- selvatique
- urbain
- … et rural ?
cycle moustique – virus – homme (1)
Copyright CDC
cycle moustique – virus – homme (2)
1. Virus transmitted to human
in mosquito saliva
2. Virus replicates
in target organs
3. Virus infects white blood
cells and lymphatic tissues
4. Virus released and
circulates in blood
Copyright CDC
cycle moustique – virus – homme (3)
5. Second mosquito ingests
virus with blood
6. Virus replicates in mosquito
midgut and other organs,
infects salivary glands
7. Virus replicates
in salivary glands
Copyright CDC
MANIFESTATIONS CLINIQUES DENGUE
Infection par la Dengue
Asymptômatique
Fièvre indifférenciée
(Syndrome viral)
Symptômatique
Fièvre eruptive et algique
(Syndr. Dengue)
Pas
d’hémorragie
Dengue classique DC
Parfois avec
hémorragie
Fièvre Dengue
Hémorragique
Sans
choc
avec choc: DSS
Dengue hémorragique
DHF
Warning Signs for Dengue Shock
Copyright CDC
DHF: évolution temporelle
de paramètres clin-biol (+ 2 SD)
Copyright CDC
Éruption de DF
Éruption de DF
Éruption de DF
DFclassique signes hémorragiques mineurs :
gingivorragies
FD : Purpura spontané
Purpura provoqué :
tourniquet test
DHF : syndrome hémorragique
www.med.sc.edu:85/ mhunt/arbo.htm.
(photo C Hatz, ITS)
DHF : épanchements séreux
DHF : épanchements séreux
Increased Probability of DHF
Copyright CDC
ELISA Test for Serologic Diagnosis
Copyright CDC
Temperature, Virus Positivity, and AntiDengue IgM, by Fever Day
Copyright CDC
Ig M/Ig G DENGUE RAPID TEST
INTERPRETATION OF THE RESULTS
CONT
ROL
C
IgG
IgM
RES
ULT
Sero
Negative
CONT
ROL
C Pos.
IgG Neg.
IgM Neg.
RES
ULT
Primary
Infection
CONT
ROL
CONT
ROL
C Pos.
IgG Neg.
IgM Pos.
RES
ULT
Secondary
Infection
C Pos.
IgG Pos.
IgM Pos.
RES
ULT
C Pos.
IgG Pos.
IgM Neg.
Past or Secondary
Infection
Read the test results after 15 to 30 minutes.
Negative results must be confirmed at 30 minutes.
Dengue
sérologie :
- infect. Iaire
- infect 2ndaire
www.panbio.com.au/modules. php?name=Content&pa....
Volume replacement
flow chart
for patients with
DHF grade I - II
- Haemorrhagia.
- Thrombocytopenia.
- Hematocrit
rise.
Initiate intravenous therapy (IV)
6ml/kg/h crystalloid solution for 1 -2 hrs
Improvement
Reduce IV 5ml/kg/h
Crystalloid solution for 1 - 2 hrs
Further improvement
Reduce IV 3ml/kg/h
Crystalloid solution for
6-12 hrs
Discontinue IV therapy
after 24 hrs
·
·
·
No improvement
Increase IV
10ml/kg/h crystalloid solution
for 2 hrs
Improvement
Reduce IV 6ml/kg/h
Crystalloid with further
reduction to 3ml/kg/h
Discontinue IV therapy
after 24 - 48 hrs
Improvement: Hematocrit falls, pules rate and blood pressure stable,
urine output rises.
No improvement: Hematocrit rises pulse rate rises, blood pressure
falls below 20 mmHg, urine output falls.
Unstable signs: Urine output falls, signs of shock appear.
- No improvement
- Unstable vital signs
See V dume
r e placement
grade III (next)
Volume replacement flow chart for patients with DHF grade III, IV
- Unstable vital signs.
- Urine output falls.
- Signs of shock.
Immediate, rapid volume replacement:
Initiate IV therapy 15 ml/kg/h crystalloid
Solution for 1 hr
Improvement
No improvement
Oxygen
IV therapy 10ml/kg/h
Crystalloid solution for 1 - 2 hrs
Further improvement
IV therapy by crystalloid
sol. 5ml/kg/h for 4 - 5 hrs
Further improvement
IV therapy by crystalloid
sol. 3ml/kg/h for 5 - 6 hrs
Discontinue IV therapy
after 24 - 48 hrs
IV colloid (dextran 40, plasma)
10 - 20 ml/kg/h for 1 - 2 hrs
- No improvement
Improvement
IV colloid 5ml/kg/h
for 2 - 3 hrs
Establish central venous
access and urinary catheter
Improvement
Hematocrit
falls
Blood transfusion
(10ml/kg/h) if hematocrit
still>35%
Hematocrit
rises
IV colloid as bolus
repeat if necessary
Contrôle de la dengue (1): lutte anti-Aedes
Lutte anti-Aedès : utiliser les larvicides
www.niaid.nih.gov/.../ bugborne01/dengue.htm
Larvicide
le +
employé
= Abate
(temephos)
(organophosphoré)
Exemples des gîtes larvaires
Gîtes larvaires : enlever, nettoyer,
entretenir, couvrir, mettre de l’abate…
12 WHO recommendations
1. Dengue fever (DF) is a serious viral disease transmitted by an Aedes mosquito;
2. DF occurs in 2 forms: Dengue fever (DF) and Dengue Haemorrhagic Fever (DHF)
3. DF is an acute viral disease affecting older children & adults, rarely fatal;
4. DHF more severe: bleeding - occasionally shock can be fatal, mostly in children;
5. Suspected subjects need early recognition and treatment of DHF : it can be
lifesaving ; unless promptly & adequately treated, the patient may shock & die.
6. Severe abdominal pains, black stools, skin/nose/gums bleeding, sweating, cold
skin are danger signs. If any one noticed, go to hospital & give fluids
7. Give nutritious food and fluids to drink to the patients incl. during transfer;
8. Dengue mosquitoes bite during the day;
9. Patient should use mosquito net or stay in screened room during the illness;
10. Screen your rooms for mosquitoes (or use mosquito nets / or repellent );
11. Discard objects in which water collects (tin, can, coconut shell, etc. dont allow
water to collect in pits around house. All stored water containers should be
covered all the time. This will prevent breeding of Dengue mosquitoes
12. Doctors / health workers treating cases of DF should notify health authorities