Presentation on Dengue Fever as a CME activity by myself

1. DENGUE FEVER
Dr. Wasantha Kumara
Wadi Al-Jizzi Hospital

2. OUTLINE OF THE PRESENTATION
• Introduction
• Epidemiology
• Clinical syndrome and phases of Dengue
• Prevention and control
• Management

3. INTRODUCTION
• Most rapidly spreading mosquito-borne viral disease
• Causing acute febrile illness
• Can cause severe clinical symptoms and possibly death
• Virus - Dengue Virus
• Mosquito - Aedes aegypti

4. EPIDEMIOLOGY
• Found in,
• Tropical and subtropical regions across the world
• Some temperate parts of Africa, Europe, the Middle East, and North and
South America.
• Each year
• 390 million dengue infections occur around the world
• Up to 36,000 deaths

6. Dengue fever reported and rate per
100 000 population in Oman from
2013 to 2020

7. RECENT OUTBREAK IN OMAN
• Up to 22nd May 2022,
• Total of 127 cases of Dengue Fever
• 39 patients required hospitalization
• 86.2% were Omani citizens
• 90% of the patients were from Muscat governorate
• 81% from Bawshar District
• No deaths reported

9. INCUBATION PERIOD

10. CLASSIFICATION OF CLINICAL PRESENTATION
(According to 1997 WHO case definition)
• Dengue Fever (DF), Acute febrile viral disease frequently presenting
with headaches, bone or joint and muscular pains, rash and
leukopenia as symptoms.
• Dengue Haemorrhagic fever (DHF), High fever, haemorrhagic
phenomena, often with hepatomegaly and, in severe cases, signs of
circulatory failure.
• Dengue Shock Syndrome (DSS), Patients develop hypovolemic shock
resulting from plasma leakage.

11. DENGUE – WHO CASE DEFINITION (2009)

12. PHASES OF INFECTION IN DENGUE FEVER

13. CLINICAL FEATURES – FEBRILE PHASE
• Abrupt onset of high fever and any of the following:
• Severe headache
• Retro orbital pain
• Myalgia
• Arthralgia
• Transient macular or maculopapular rash
• Minor hemorrhagic manifestations, (e.g. petechiae, ecchymosis, purpura, epistaxis,
bleeding gums, hematuria or a positive tourniquet test)
• Facial flushing or erythema
• Injected oropharynx
• Anorexia

14. LABORATORY FINDINGS – FEBRILE PHASE
• Leukopenia
• Mild to moderate thrombocytopenia
• Elevated aspartate aminotransferase (AST)
• Elevated alanine aminotransferase (ALT)
• Hyponatraemia

15. COMPLICATIONS – FEBRILE PHASE
• Dehydration
• Hyponatraemia
• Febrile seizures in young children
• Neurologic disease manifestations, including encephalitis and aseptic
meningitis

16. CRITICAL PHASE
• Onset of the critical phase can be identified by:
• Rapid decline in platelet count with a rise in hematocrit (HCT)
• The patient might develop leukopaenia up to 24 hours before platelet drop is
recognized
• Medical complications during the critical phase:
• Hypovolemic shock from plasma leakage
• End organ impairment due to prolonged shock
• Severe hemorrhage
• Encephalopathy

17. WARNING SIGNS – CRITICAL PHASE
• Clinical fluid accumulation such as ascites or pleural effusion
• Liver enlargement > 2 cm below the costal margin
• Severe abdominal pain
• Persistent vomiting (at least 3 vomiting episodes within 24 hours)
• Mucosal bleed
• Lethargy or restlessness

18. RECOVERY PHASE
• Clinical manifestations during the recovery phase:
• A second rash that might be macular or erythematous with small
circular islands of normal, unaffected skin. This convalescent rash
can be very pruritic and desquamate.
• Severe fatigue

19. LABORATORY FINDINGS – RECOVERY PHASE
• Hematocrit stabilizes or is slightly lower due to a dilutional effect of
reabsorbed plasma (hemodilution).
• White blood count (WBC) begins rising soon after become fever-free.
• Platelet count increases following WBC recovery.

20. CAUSES OF DEATH
• Severe dengue can result in death. Causes include:
• Unrecognized dengue without appropriate medical management
• Unrecognized or prolonged shock
• Unrecognized occult haemorrhage
• Fluid overload
• Nosocomial infections
• Liver failure

21. PREVENTION AND CONTROL
• Vaccine to prevent dengue (Dengvaxia®)
• Measures to reduce mosquitoes
• Measures to protect against mosquito bites

22. MEASURES TO REDUCE MOSQUITOES
• Eliminate the places where the mosquito lays her eggs, such as artificial
containers that hold water.
• Clean inside of water containers to remove mosquito eggs (such as pet water
bowls, flower planter dishes).
• Cover water storage barrels.
• Empty and clean containers with standing water indoors, such as vases, at least
once a week.
• Empty or dispose of containers or other items that can hold water outdoors, such
as discarded tires, trash containers, buckets, planters, toys, pools and birdbaths.

23. MEASURES TO PROTECT FROM MOSQUITO BITES
• Use repellent on skin while indoors or out and reapply every several
hours.
• Wear long sleeves and pants.
• Make sure window and door screens are secure and without holes.
• Use mosquito nets
• Use air-conditioning.

24. MANAGEMENT
• No specific antiviral agent against Dengue virus.
• Management decisions are based on,
• Clinical manifestations
• Severity of illness
• Presence of pre-existing medical conditions
• Other circumstances facing patients and their families

25. DENGUE MANAGEMENT GROUPS
• Group A — Patients are sent home
• Group B — Patients are referred for hospital management
• Group C — Patients are admitted for emergency treatment and
intensive care

27. GROUP A PATIENTS
• Before sending Group A patients home, provide appropriate guidance
about caring for the patient at home including,
• Typical clinical course
• Warning signs
• When to follow up

28. AT HOME
• With Fever,
• Bed rest
• Control high fever – Paracetamol and Tepid sponging (Avoid Aspirin or other
NSAIDS and Steroids, Avoid antibiotics unless indicated)
• Prevent dehydration – Give plenty of fluids, and watch for signs of dehydration
• Prevent spread of dengue inside your house
• As fever goes away,
• Watch for warning signs

29. AT THE FOLLOW-UP VISITS
A health care professional should,
• Assess the patient’s hemodynamic status for early signs of shock.
• Determine if the patient is entering the critical phase.
• Evaluate the patient for medical complications including dehydration.
• Ask the patient about the presence of warning signs for severe dengue.
• Draw a complete blood cell count (CBC) and evaluate for
hemoconcentration and thrombocytopenia.

30. GROUP B AND C PATIENTS
• Require hospital monitoring and treatment.
• These patients require the following interventions:
• Monitoring hemodynamic status and tracking intake and output
• Use of HCT to guide interventions
• Use isotonic intravenous fluids (IVFs) to restore plasma volume
• Monitoring for signs of occult bleeding
• Use of blood products as needed
• Correction of metabolic acidosis, use of electrolytes as needed
• Use of colloids for refractory shock

31. INTRAVENOUS FLUIDS
• It is important to know what type of fluids to give, when to give
them, and how much to give.
• Limit IVFs in the febrile phase to patients who are dehydrated and
will not take enough liquid by mouth.
• Give minimum IVFs to maintain good perfusion and urine output of
at least 0.5 ml/kg/hr during the critical phase.
• Reduce IVFs as the rate of plasma leakage decreases and stop IVFs
when patient begins to diurese and is stable.

32. MAINTENANCE IV FLUIDS
• Normal maintenance fluid per hour can be calculated based on following
Holliday-Segar formula:
4 mL/kg/h for first 10 kg body weight
+ 2 mL/kg/h for next 10 kg body weight
+ 1 mL/kg/h for subsequent kg body weight
• For overweight or obese patients, calculate the normal maintenance fluid
based on ideal body weight (IBW).
• IBW for a 6-year-old child is 20–25 kg. Therefore correct maintenance IVF
rate is 60–65 mL/hour.

34. TREATMENT OF HAEMORRHAGE
• Packed red blood cells (PRBC) or whole blood (if volume is not an issue for
the patient) should be given to dengue patients who have clinically
significant occult or overt hemorrhage.
• Give 5–10 mL/kg of PRBC or 10–20 mL/kg of whole blood at appropriate
rate and observe the clinical response.
• Consider repeating the blood transfusion, if
• There is further blood loss.
• There is no appropriate increase in HCT after blood transfusion. For instance, an
appropriate increase is 3%–4% rise in HCT for every 10 cc/kg of PRBC given.

35. GROUP B WITHOUT WARNING SIGNS
• Encourage oral fluids. If not tolerated, start IVFs (Normal Saline or Ringer's
lactate) with or without dextrose at maintenance rate. Patients might be
able to take oral fluids after a few hours of IVF therapy.
• Monitor body temperature and document defervescence.
• Record intake and output including vomiting, diarrhoea, and urine output.
• Observe patient for warning signs.
• Monitor HCT, WBC, and platelet count.

36. GROUP B WITH WARNING SIGNS
• Observe patient for signs of plasma leakage, early signs of shock, and occult bleeding.
• Maintain a detailed fluid balance.
• Monitor parameters including
• Vital signs and peripheral perfusion (every 1–2 hours until patient is out of critical phase)
• HCT (before and after IVFs, then every 6–8 hours)
• Blood glucose every (6–12 hours)
• Electrolytes and other organ functions as indicated by clinical status (liver function tests
[LFTS], acid-base)

37. GROUP C PATIENTS
As Group C patients have severe dengue, use the following
intervention:
• Use colloids for refractory shock
• Monitor patient for occult bleeding
• Use blood products as needed for clinically significant bleeding

39. GROUP C - MONITORING
• Frequent vital signs and hemodynamic assessments
• Detailed fluid balance of all input and output
• End organ function including liver and renal function tests, glucose,
and acid-base balance
• Mental status

40. WHEN TO DISCHARGE
Patients can be discharged from the hospital when all of the following occur:
• No fever for 24–48 hours
• Improvement in clinical status
• General well being
• Appetite
• Hemodynamic status
• Urine output
• No respiratory distress
• Increasing trend of platelet count (usually preceded by rising WBC)
• Stable HCT with adequate oral intake while off IVFs

41. TAKE HOME MESSAGE FOR YOU
Prognosis of Dengue patients depends on,
• Early diagnosis
• Recognition of warning signs and early signs of shock
• Timely initiation of correct management

42. References
• Dengue Clinical Case Management (DCCM), Version 1.3, July 2018, Centers
for Disease Control and Prevention – USA
• Dengue guidelines for diagnosis, treatment, prevention and control – New
Edition, 2009, World Health Organization.
• Epidemiological and Clinical Characteristics of Patients with Dengue Fever
in a Recent Outbreak in Oman: A Single Center Retrospective-cohort Study,
2022, Oman Medical Journal [2022], Vol. 37, No. 6: e452
• W.H.O. (2009). DENGUE GUIDELINES FOR DIAGNOSIS, TREATMENT, PREVENTION
AND CONTROL. Retrieved from www.who.int/tdr