Dengue Fever

Question 1

Epidemology:

Where is it found?

Etiology:
- How is it transmitted?

Answer 1

Tropical regions - SOUTHERN ASIA

Vector-borne - mosquitoes - Aedes aegypti

Question 2

Clinical Features:

Classic dengue fever:

Incubation 2-14 days - If symptoms appear more than 2 weeks after returning from a dengue-endemic region, it is very unlikely that dengue is the cause!

What age group is asymptomatic?

1st wk - 2 symptoms?
What are other features of infection that may be seen?

Dengue Haemorrhagic Fever:

Happens in 1-2% of cases.

What happens to the fever?

When does it tend to develop?

What are some manifestations of haemorrhage?

They also get:
- Abdo pain and vomiting
Confusion
- Pleural effusion and/or ascites - increased vascular permeability

GO INTO SHOCK

Answer 2

Children

Fever + malaise

Arthralgia and myalgia - bone and muscle pain
Headache
Maculopapular rash
Generalised lymphadenopathy

=======
Temperature change: ranges from hypothermia
to a second spike in fever

About 1 wk after onset

Petechiae
Epistaxis
Gingival bleeding

Question 3

Diagnosis:

1-5 days post onset of fever:
- What is measured in the blood?

> 5 days post onset of fever:
- What is measured in the blood?

Continual testing done to look for rise

Answer 3

Viral RNA (RT-RNA)
Viral antigens 

IgM antibodies - host response - last up 6 months - only suggests PREVIOUS INFECTION

IgG antibodies - evidence of past infection - lasts a lifetime

Question 4

Management:

Treat dehydration and replace ongoing losses in haemorrhagic fever.

What can be used to bring down the temperature?

Answer 4

Paracetamol - Acetaminophen

Question 5

Prevention:

How to avoid?

Answer 5

Avoid exposure, use of mosquito repellent

A tetravalent attenuated live vaccine
(CYD-TDV) has been approved for use in children between 9–16 years of age who live in endemic areas and have a laboratory confirmed prior dengue virus
infection.