Checking in on chikungunya: The importance of regular reviews of surveillance data

Author(s):  Dr Sherilyn Houle

Chikungunya is a virus transmitted by Aedes mosquitoes.¹ While most people infected will survive, acute and chronic severe joint pain as well as the potential for ocular, cardiac, or neurologic sequelae¹ warrant traveler education and specific measures such as bite prevention, repellent use, and possibly vaccination depending on patient factors and product availability.²

It can be challenging to keep current on where chikungunya is circulating and the risk to a traveler, given its complicated epidemiology. Initially, chikungunya was believed to have been endemic in tropical and subtropical regions of sub-Saharan Africa.³ Following an outbreak in Kenya in late 2004, one of two lineages of the virus spread to a number of locations in the Indian Ocean, India, and parts of Southeast Asia, with travelers believed to have also seeded transmission in other countries, including Italy and France.³ The first autochthonous cases of chikungunya were identified in the Western Hemisphere in 2013.³ To date, over 100 countries worldwide have been impacted, spanning the Americas, Asia, Africa, and Europe.¹

Complicating this, urban transmission of the virus is associated with periodic outbreaks separated by periods of no circulation.^3-4 Modeling has estimated an average period of 6.2 years between outbreaks (95% CI: 5.1-7.6) and that the mean percentage of the susceptible population infected during outbreaks was 8.4% (95% CI: 7.2-9.1%).⁴ Therefore, we must consider not only where a traveler is going but also the current local status, which may rapidly change.

For those looking for information on the status of chikungunya worldwide, the European Centre for Disease Prevention and Control publishes monthly reports that include both a global overview and country-specific case and outbreak information, available at https://www.ecdc.europa.eu/en/chikungunya-monthly. I recommend bookmarking this page and visiting it regularly to check in on chikungunya and educate travelers on their risk.

References

[1].  Chikungunya.  World Health Organization [link]
[2].  Chikungunya.  Staples JE, Hills SL, Powers AM ‐ CDC Yellow Book 2026 [link]
[3].  Chikungunya virus: epidemiology, replication, disease mechanisms, and prospective intervention strategies.  Silva LA, Dermody TS ‐ J Clin Invest 2017;127(3):737-749 [link]
[4].  Chikungunya virus disease worldwide overview.  European Centre for Disease Prevention and Control [link]