Callum Narita, Editorials and Publications Team PMSA
Chikungunya is an infectious disease caused by the chikungunya virus (CHIKV), spread by infected mosquitoes in endemic areas. The condition presents similarly to dengue fever, another mosquito-borne disease. After a latent period ranging 2-12 days, it leads to symptoms including malaise, fever, rash and severe joint pain and stiffness, often the most debilitating aspect of the infection(1).
Whilst the infection generally clears after 3-7 days, symptoms, particularly joint pain, can persist for a long period after resolution. This potentially leads to long term morbidity and disability(1). Additionally, at risk populations, including perinatal infections, newborns, and the elderly, can have more severe infections, rarely resulting in encephalitis(2), and potentially leading to increased mortality rates in endemic regions(3). There are currently no cures or treatments available other than symptomatic relief.
Since it was first recognised, the disease has been identified and diagnosed in many regions around the world, including Western Pacific countries, and Pacific Island Countries and Territories (PICT)(4). An outbreak in Papua New Guinea in 2012 demonstrated how rapidly the disease can spread, both locally and internationally(4). Island nations in the Indian Ocean struggled with high patient numbers when dealing with CHIKV outbreaks. There was a lack of facilities available to manage the significant load of patients, as island nation healthcare systems are typically geared towards primary care(4). A similar situation in the limitation of available healthcare presents itself in PICTs. The virus has now been identified in several Pacific Nations, and there have been a number of epidemics throughout the region. The disease has since spread to at least eight other Pacific nations(5).
As there is no treatment available, prevention is paramount in the management of global chikungunya, and to protect PICT from epidemics. Given the virus is mosquito-borne, the prevention strategies are similar to malaria, or any other mosquito-borne virus. This is mainly through individual protection measures, including long-clothing, mosquito repellent and mosquito nets. More extreme measures of reducing the incidence of the disease include mosquito population control. Recent trials in Australia of one such method have managed to reduce dengue-fever bearing mosquito populations by a significant proportion(6). Infertile, non-biting males were introduced into the environment This exciting development has implications for insect-borne viruses across the globe. A similar program could potentially be implemented for chikungunya, as both diseases can be spread by the same mosquito.
1. Pialoux G, Gaüzère B-A, Jauréguiberry S, Strobel M. Chikungunya, an epidemic arbovirosis. The Lancet infectious diseases. 2007;7(5):319-27.
2. Economopoulou A, Dominguez M, Helynck B, Sissoko D, Wichmann O, Quenel P, et al. Atypical Chikungunya virus infections: clinical manifestations, mortality and risk factors for severe disease during the 2005–2006 outbreak on Reunion. Epidemiol Infect. 2009;137(4):534-41.
3. Mavalankar D, Shastri P, Bandyopadhyay T, Parmar J, Ramani KV. Increased mortality rate associated with chikungunya epidemic, Ahmedabad, India. Emerg Infect Dis. 2008;14(3):412.
4. Roth A, Hoy D, Horwood PF, Ropa B, Hancock T, Guillaumot L, et al. Preparedness for threat of chikungunya in the pacific. Emerg Infect Dis. 2014;20(8).
5. Musso D, Rodriguez-Morales AJ, Levi JE, Cao-Lormeau V-M, Gubler DJ. Unexpected outbreaks of arbovirus infections: lessons learned from the Pacific and tropical America. The Lancet Infectious Diseases. 2018;In Press.
6. Young A. Trial wipes out more than 80 per cent of disease-spreading mozzie: Commonwealth Science and Industrial Research Organisation,; 2018 [Available from: https://www.csiro.au/en/News/News-releases/2018/Trial-wipes-out-more-than-80-per-cent-of-disease-spreading-mozzie.