Chikungunya

Question 1

What is the organism responsible for Chikungunya?

Answer 1

Chikungunya virus (alphavirus)

The Chikungunya virus is primarily transmitted through mosquito bites.

Question 2

Is Chikungunya nationally notifiable?

Answer 2

Yes - routine, labs and doctors

Question 3

How is Chikungunya primarily transmitted?

Answer 3

Via mosquito bite, mainly by Ae. aegypti and *Ae. albopictus

Both day-biting mosquitos

These mosquitoes are known for biting during the day.

Question 4

What are the main reservoirs for Chikungunya?

Answer 4

Monkeys and humans

Human-mosquito-human transmission occurs during outbreaks.

Question 5

T / F: Chikungunya can be transmitted from human-to-human via mosquitoes

Answer 5

True - during outbreaks

Question 6

How can Chikungunya be transmitted?

Answer 6

• Animal-to-human (via mosquito)
• Human-to-human (via mosquito)
• Bloodborne
• Vertical

Question 7

Where is Aedes aegypti found in Australia?

Answer 7

Central and North QLD

Question 8

Where is Aedes albopictus found in Australia?

Answer 8

Currently not on mainland but found on Torres Strait Islands

Question 9

What are the clinical features of Chikungunya?

Answer 9

Fever, headache, rash, severe joint pain, muscle pain, N/V

Symptoms are generally more severe than those of Ross River virus (RRv) or Barmah Forest virus (BFv).

Question 10

What is the incubation period for Chikungunya?

Answer 10

2-12 days; usually 3-7 days

This period follows exposure to the virus.

Question 11

What is the infectious period for Chikungunya?

Answer 11

Humans infectious to mosquitoes while viraemic - up to 12 days post Sx onset (usually 2-6 days)

Mosquitoes infectious 2-10 days later

Question 12

How long do symptoms of Chikungunya typically last?

Answer 12

Usually lasts 3-10 days, but arthralgia, myalgia, lethargy can persist for months

Compared to dengue, Chikungunya presents more intense joint pain.

Question 13

Who are considered high-risk groups for Chikungunya?

Answer 13

Travellers to endemic areas (esp. if spending time outside), older individuals, and those with comorbidities

These groups are at higher risk of complications and death.

Question 14

What is the definition of a confirmed Chikungunya case?

Answer 14

Isolation/detection/seroconversion, or IgM in absence of RRv and BFv

Question 15

What methods are used for diagnosing Chikungunya?

Answer 15

PCR or serology (IgM detectable 5+ days after onset)

Question 16

What is the outbreak definition for Chikungunya?

Answer 16

Single locally-acquired case

This helps in monitoring and controlling outbreaks.

Question 17

In which regions does Chikungunya occur?

Answer 17

Africa, India, South East Asia, Pacific, Europe, and the Caribbean

Emerging transmission has been reported globally.

Question 18

What are the prevention strategies for Chikungunya?

Answer 18

• Standard mosquito prevention
• Education on minimising exposure

Especially if travelling to endemic areas.

Question 19

What resources are available for PH management of Chikungunya?

Answer 19

DH protocol (no SoNG)

Question 20

How are cases of Chikungunya managed?

Answer 20

Interview - exposure hx - travel, mosquito bite, outdoor activities
T - clinician
I - ?possible in outbreak situation due to human-mos-hum transmission
E - bite avoidance: personal protection, stay indoors (nets/screens), avoid travel to FNQ (vectors present)

Question 21

How are contacts / co-exposed managed?

Answer 21

No follow-up
HH contacts / those living nearby should avoid mosquito bites if vector present

Question 22

What is the recommended action if local transmission of Chikungunya is suspected?

Answer 22

• Notify DH/entomology team
• Active case finding
• Enhanced surveillance - mosquito surveys
• Vector control
• Clinician alerts + public health alerts
• Reinforce mosquito avoidance measures
• Consider travel restrictions to affected area

Question 23

True or False: Chikungunya has been reported to have local transmission in Australia.

Answer 23

False

All reported cases in Australia have been acquired overseas.