Dengue fever

Question 1

What is dengue fever?

Answer 1

Self limiting flu-like illness
Caused by dengue virus - type of flavivirus

Question 2

What is dengue fever spread by and where?

Answer 2

Aedes aegyptu
Aedes albopictus
Southeast Asia, africa, Pacific and Americas

Question 3

Four serotypes of dengue virus

Answer 3

DEN-1
DEN-2
DEN-3
DEN-4

Question 4

How do serotypes and imunity to degnue work?

Answer 4

Life long immunity after ill
If prev immunity to one serotype and infected by another -> severe dengue

Question 4

How do serotypes and imunity to degnue work?

Answer 4

Life long immunity after ill
If prev immunity to one serotype and infected by another -> severe dengue

Question 5

Incubation for dengue

Answer 5

2-7 dyas

Question 6

Phases of dengue fever

Answer 6

Febrile phase
Critical
Recovery

Question 6

Phases of dengue fever

Answer 6

Febrile phase
Critical
Recovery

Question 7

Risk factors

Answer 7

Live/travel endemic areas
Poor public hygeine
High population density

Question 8

Febrile phase clinical features

Answer 8

High grade fever
Maculopapular rash
Facial flushing
Muscle and joint pains
Severe headache
Retro-orbital pain
Nausea and vomitting

Question 9

How long is febrile phase dengue

Answer 9

2-7 days

Question 9

How long is febrile phase dengue

Answer 9

2-7 days

Question 10

Clincal examination findings febrile phase dengue

Answer 10

Maculopapular rash sparing palms and soles

Question 10

Clincal examination findings febrile phase dengue

Answer 10

Maculopapular rash sparing palms and soles

Question 10

Clincal examination findings febrile phase non severe dengue

Answer 10

Maculopapular rash sparing palms and soles
Positive tourniquet test

Question 11

What is a positive tourniquet test?

Answer 11

there is >20 petechiae per 2.5cm.2

Question 12

Critical phase how long last and what it is?

Answer 12

After third day fever
Lasts 24-48 hours
Increase in capillary permeability with drop in body temperature

Question 13

Symptoms of critical phase

Answer 13

Severe abdominal pain
Persistnet vomitting
Rapid breathing
Lethargy
Altered LOC
Restlessness

Question 14

Dengue with warning signs what not to miss

Answer 14

Haemorrhageic manifestatiosns
=Petechiae, mucosal, membrane bleeding na d menorrhagia
Enlarged and tender liver
Evidence of shock - prolonged cap regill time

Question 15

Signs of severe dengue

Answer 15

Clinical fluid accumulation = pleural effusion, ascites
Periorbital oedema
Hypovolaemic shcol
Severe bleeding

Question 15

Signs of severe dengue

Answer 15

Clinical fluid accumulation = pleural effusion, ascites
Periorbital oedema
Hypovolaemic shcol
Severe bleeding

Question 16

Recovery phase time and signs

Answer 16

Leaked plasma reabsorbed into blood
48-72 hours
‘isles of white in a sea of red’

Question 17

Severity classes dengue

Answer 17

Probable dengue
Dengue with warning signs
Severe dengue

Question 17

Severity classes dengue

Answer 17

Probable dengue
Dengue with warning signs
Severe dengue

Question 18

What is the criteria for probable dengue

Answer 18

1 - Live in or travel to dengue endemic areas 2 - fever 3 - 2 of follwong: -N+V -Rash -Aches and pains -Positive tourniquet test -Leukopenia -Any warning sign

Question 19

Dengue with warning signs

Answer 19

1 - Abdominal pain 2 - Persistent vomitting 3 - Clinical fluid accumulation 4 - Mucosal bleed 5 - lethargy 6 - restlessness 7 - tender liver 8 - increase in haematocrit with rapid decrease in platelet count

Question 20

Severe dengue criteria

Answer 20

1 - Severe plasma leakage -Dengue shock syndrome -Fluid accumulation with respiratory distress 2 - Severe haemorrhage 3 - Severe organ impairement -Liver impairment -CNS impairment -Cardiac failure

Question 21

Differential diagnosis

Answer 21

Malaria Typhoid fever HIV seroconversion Infectiours mononucleosis Measkes Erythe,a infectiosum Chikungunya Zika virus COVID-19

Question 22

How to investigate denfue fever

Answer 22

BP FBC, LFTs, U+Es, coag screen CXR NSI antigen test IgM antiboides with ELISA IgG antibodies with ELSIA

Question 23

What look for in FBC, LFT, U+Es?

Answer 23

-Raised haematocrit and low platelet count suggests dengue warning signs (may also present with neutropenia + leukopenia) -Raised ALT and AST - organs involved Coag - prolonged APTT + PT

Question 24

When is NSI antigen detected?

Answer 24

First 4 days og illness

Question 25

When are IgM antibodies for dengue detected?

Answer 25

After 5 days os illness Peaks 2 weeks after onset symptoms

Question 26

When are IgG antibodies detected and what used for

Answer 26

After 7 days of illness, lasts for life - used to confirm secondary infection

Question 27

Key management of dengue

Answer 27

PHE notify Control fever with paracetemil IV fluid resus w close monitor - prevent overload Escalate patients with warning signs and severe dengue to secondary facility

Question 28

Prevention of dengue

Answer 28

Wear long sleeved clothes Insect repellent Remove soruces of breeding sites

Question 29

Complications of dengue

Answer 29

Dengue haemorrhagic fever DIC Dengue shock sundreom Severe organ involvement eg cardiac failure, liver impairment

Question 30

Effects of dengue in pregnancy

Answer 30

Death of foetus Low BW Prematurity

Question 30

Effects of dengue in pregnancy

Answer 30

Death of foetus Low BW Prematurity