Dengue fever

Headline
Etiology mosquito-borne flavivirus (enveloped, single-stranded positive-sense RNA virus). Hard to distinguish between arboviruses!
Epidemiology Spread by Aedes mosquitoes (day-biting)
- Asia 70% of disease burden
- Children more likely to develop dengue haemorrhagic fever

Risk factors for severe dengue
- pregnancy
- age <1 year or age >65
- hypertension, CKD, heart failure, obesity, asthma
Clinical presentation retro-orbital pain, headache, rash (3-5 days before fever), fever (day 5-7, lasts 2-3 days), arthralgia
papular → petechial → desquamating rash

warning signs: vomiting >3x in 1h, mucosal bleeding, third spacing (e.g. gallbladder oedema), rapid ↓ in platelets, hepatomegaly, lethargy, restlessness

severe dengue: shock, bleeding, respiratory distress
Pathogenesis
Diagnostic investigations 3x blood cultures are diagnostic!
Bloods: ↑ ALT; FBC normal
Complications: Dengue haemorrhagic shock/”severe dengue”– if previous episode
Management Supportive, most are self-resolving 3-7d
➥ Warn pts – can be followed by 6-8/52 severe fatigue
➥ IV fluids
➥ generally avoid empirical NSAIDs or abx
➥ Prevention: vector control, preventing bites. Globally there are vaccinations but idk how available in the UK