Dengue PCF.pptx sssssssssssssssssssssssssssssssss

sadfas

1. Dengue Fever Dr. Justin Paul R. Roa Municipal Health Officer

2. Overview Definition of Terms Etiology Epidemiology Clinical Manifestation Classifications Diagnostics Management Prevention

3. Definition of Terms Dengue fever is a benign syndrome caused by several arthropod-borne viruses and is characterized by biphasic fever , myalgia or arthralgia, rash , leukopenia , and lymphadenopathy .

4. Definition of Terms Dengue Hemorrhagic F ever Philippine, Thai, or Singapore hemorrhagic fever; hemorrhagic dengue; acute infectious thrombocytopenic purpura a severe, often fatal, febrile disease caused by 1 of 4 dengue viruses. characterized by capillary permeability , abnormalities of hemostasis , and, in severe cases, a protein-losing shock syndrome .

5. Dengue Epidemiology Most rapidly spreading mosquito-borne viral disease in the world More than 390 million dengue infections occur annually Approximately 96 million have clinical disease 75% of the current global disease burden due to dengue – South-East Asia & Western Pacific Regions

6. Dengue Epidemiology Average annual number of DF & DHF cases WHO, 1955–2007

7. Dengue Fever Vectors Aedes mosquitoes, principally Ae. Aegypti – immature stages are found in water-filled habitats, mostly in artificial containers closely associated with human dwellings

8. Dengue Fever Vectors Aedes albopictus, Aedes polynesiensis &species of the Aedes scutellaris complex – Caused outbreaks

9. Clinical Manifestations Dengue Fever incubation period is 1-7 days Infants and young children: may be undifferentiated or characterized by fever for 1-5 days , pharyngeal inflammation , rhinitis , and mild cough .

10. Clinical Manifestations Dengue Fever O lder children and adults: sudden onset of fever, with temperature rapidly increasing to 39.4-41.1°C (103- 106°F), usually accompanied by frontal or retroorbital pain , particularly when pressure is applied to the eyes. Occasionally, severe back pain precedes the fever (back-break fever).

11. Clinical Manifestations Dengue Fever Transient, macular, generalized rash that blanches under pressure seen during the first 24-48 hours of fever . pulse rate may be slow relative to the degree of fever Myalgia and arthralgia occur soon after the onset of fevers and increase in severity over time.

12. Clinical Manifestations Dengue Fever From the 2nd-6th day of fever nausea and vomiting are apt to occur, and generalized lymphadenopathy , cutaneous hyperesthesia or hyperalgesia , taste aberrations , and pronounced anorexia may develop

13. Clinical Manifestations Dengue Fever Approximately 1-2 days after defervescence : a generalized, morbilliform, maculopapular rash appears that spares the palms and soles It disappears in 1-5 days; desquamation may occur.

14. Clinical Manifestations Dengue Fever About the time this second rash appears, the body temperature, which has previously decreased to normal, may become slightly elevated and demonstrate the characteristic biphasic temperature pattern. 40 1 2 3 4 5 6 7 8 9 10

15. Phases of Dengue Infection

16. DHF: FEBRILE PHASE high-grade fever Lasts for 3–7 days , often accompanied by facial flushing, skin erythema, generalized body ache, myalgia, arthralgia and headache

17. DHF: FEBRILE PHASE Sore throat, injected pharynx & conjunctival injection Anorexia, nausea & vomiting earliest abnormality in the full blood count is a progressive decrease in WBC count

18. Course of dengue illness: F ebr i le Cr i tical Recovery Phases Days of Illness Temperature Potential clinical issues Laboratory changes Virology/serology Viraemia Reabsorption Fluid overload Dehydration P l a t el e t Hematocrit I gM /I gG 40 1 2 3 4 5 6 7 8 9 10 Shock Bleed i ng Organ Impairment

19. DHF: CRITICAL PHASE Afebrile phase Day 3–7 of illness ↑ in capillary permeability in parallel w/ ↑ Hct - marks the beginning of the critical phase usually lasts 24–48 hours clinically significant plasma leakage

20. DHF: CRITICAL PHASE Progressive leukopenia followed by a rapid decrease in platelet count usually precedes plasma leakage degree of plasma leakage varies Pleural effusion, ascites , shock organ hypoperfusion organ impairment, metabolic acidosis & DIC

21. Course of dengue illness: F ebr i le Cr i tical Recovery Phases Days of Illness Temperature Potential clinical issues Laboratory changes Virology/serology Viraemia Reabsorption Fluid overload Dehydration P l a t el e t Hematocrit I gM /I gG 40 1 2 3 4 5 6 7 8 9 10 Shock Bleed i ng Organ Impairment

22. DHF: RECOVERY PHASE gradual reabsorption of extravascular compartment fluid takes place General well-being improves, appetite returns, GI symptoms abate hemodynamic status stabilizes and diuresis ensues May have bradycardia, stabilization of HCT, or Hemodilution “isles of white in the sea of red” (Hermann’s rash) & may have generalized pruritus

23. Clinical Problems during the different phases of dengue

24. TIPS! Dengue Warning Signs: APMC LLL A – Abdominal pain P – Persistent vomitting >3 episodes in 24 hours M – Mucosal bleed C – Clinical fluid accumulation L – Lethargy L – Leukopenia with increased HCT L – Liver enlargement >2 cm

25. Diagnostic Tests

26. DIAGNOSTICS Dengue NS-1 Antigen Useful from day 1 until day 3 of the illness

27. DIAGNOSTICS Serology (Dengue IgM/IgG) Method of choice at the end of the acute phase of infection Dengue IgM: samples should be collected not earlier than 5 days nor later than 6 weeks after onset.

28. DIAGNOSTICS Serology (Dengue IgM/IgG) Primary infection: Dengue IgG is detectable in low titers at the end of 1 st week of illness then increases slowly after (IgG detectable after several months) Secondary infection: IgG detected even in the acute phase & persists from 10 months to life

29. MANAGEMENT

30. MANAGEMENT General Not all cases should be admitted Supportive therapy is the main management Avoid ibuprofen or NSAIDS Those with warning signs or complications should be admitted Maintenance of cardiovascular and circulatory status is priority

31. PREVENTION Several types of dengue type 1-4 vaccines are under development A killed vaccine for chikungunya is efficacious but not licensed Large-scale Phase III clinical evaluations of a chimeric yellow fever/dengue tetravalent vaccine manufactured by Sanofi Pasteur reveal only moderate protection against individual dengue viruses But a reduction in hospitalization & severe disease

32. PREVENTION Possibility exists that incomplete dengue immunization may sensitize recipients, with potential that ensuing dengue infections could result in dengue hemorrhagic fever.