Dengue fever Flashcards
1
Q
infection overview
A
- Mosquito-borne tropical disease caused by the Dengue virus
- Commonest arbovirus
2
Q
how many serotypes
A
4
3
Q
patient risk factors
A
- Living or traveling in Africa, Asia, India
- Infants and young children (more common in well nourished children)
- Female
- High BMI
- Viral load
- Polymorphisms in particular genes
4
Q
pathogen
A
dengue virus
5
Q
Patient symptoms
A
- Fever
- Back pain
- Headache
- Rash
6
Q
symptoms
A
dependent on if its the first infection or a re-infection
7
Q
first infection symptoms
A
ranges from asymptomatic to non-specific febrile illness (classic dengue)
- Last 1-5 days
- Supportive treatment only
8
Q
Re-infection with different serotype symptoms
A
- Antibody dependent enhancement
o Dengue haemorrhage fever (children, hyperendemic areas)
o Dengue shock syndrome
9
Q
mechanism of infection
A
- Mosquito bites and passes virus via salvia
- Virus binds to enter WBC and replicates inside the cells
- WBC responds by releasing cytokines and interferons which cause fever and flu-like symptoms
10
Q
diagnosis
A
- Virus isolation in Cell cultures
- Nucleic acid detection by PCR
- Viral antigen and antibody detection- ELISA
11
Q
prevention
A
Based on control of and protection from the bites of the mosquito that transmits it.
- Eliminating habitats- getting rid of open sources of water or using insecticides
- Nets
- Vaccine
12
Q
vaccines are recommended to those who
A
have had prior dengue infection to prevent severe symptoms if re-infected
13
Q
Treatment
A
- No antiviral drugs for dengue
- Maintain proper fluid balance is important- IV hydration (1 or 2 days)
- Treatment depends on the symptoms
14
Q
Outcome of infection
A
- Recovery takes 2-7 days
o Most recover without ongoing problems - Can develop into dengue haemorrhagic fever
- Dengue shock
15
Q
dengue haemorrhagic fever
A
resulting in bleeding, low levels of blood platelets and blood plasma leakage
