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bioRxiv · 10.1101/061622

Differences in perceived severity of Zika virus infection and dengue fever and its influence on mosquito control practices in Malaysia, a dengue-endemic country

Abstract

BackgroundIt is important to study the concerns over the Zika virus (ZIKV) outbreak among the general public in dengue-endemic countries such as Malaysia, as both diseases are transmitted by the same vector species. Furthermore, investigation of public prevention measures for ZIKV is essential in order to identify the gaps in mosquito control practices. The aims of this study were to explore the differences in 1) the perception of severity towards ZIKV infection and dengue fever, and 2) mosquito control practices before and after the ZIKV outbreak was declared a Public Health Emergency of International Concern (PHEIC).\n\nMethodData were collected between February 2015 and May 2016 using a computer-assisted telephone interviewing system on a random sample of 567 people from the general Malaysian population aged above 18 years from randomly selected households.\n\nResultsThe median scale score for perceived severity of ZIKV was 3 (interquartile range [IQR] 1-5) versus 4 (IQR 3-5) for dengue (P<0.001). The majority perceived dengue as being more severe than ZIKV (41.6%). Having friends or acquaintances that had died from dengue was significantly associated with higher perceived severity of ZIKV than dengue (odds ratio [OR] 1.913 [95% confidence interval (CI) 1.032-3.547]). The scores for mosquito control practices before and after ZIKV was declared a PHEIC were similar, at 4 (IQR 3-5). Multivariate analysis revealed that participants with a higher score for perception of severity of ZIKV were more likely to report greater mosquito control practices after the declaration of the PHEIC (OR 1.822 [95% CI 1.107-2.998]).\n\nConclusionsThe emerging ZIKV pandemic requires concerted efforts to enhance mosquito control practices among the Malaysian public. Efforts to improve public mosquito control practices should focus on enhancing the perception of the severity of ZIKV.\n\nAuthor summaryInvestigation of the public perception of the severity of the re-emergence of Zika virus (ZIKV) in Malaysia, a dengue-endemic country, is of immense importance. It is also vital to know whether the public has heightened their mosquito prevention practices after the declaration of ZIKV as a Public Health Emergency of International Concern (PHEIC). The aim of this study was to explore the differences in 1) the perception of severity towards ZIKV infection and dengue fever, and 2) mosquito control practices before and after the ZIKV outbreak was declared a PHEIC. Findings showed that the public has a lower perception of severity of ZIKV than of dengue. Mosquito prevention practices were the same before and after the declaration of a PHEIC. People with a higher perception of severity of ZIKV reported higher mosquito control practices after the declaration of a PHEIC. The emerging ZIKV pandemic requires concerted efforts to enhance mosquito control practices among the Malaysian public. Efforts to improve public mosquito control practices should focus on enhancing the perception of severity of the ZIKV.

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Li Ping Wong, Haridah Alias, Nasrin Aghamohammadi, I-Ching Sam, Sazaly AbuBakar. 2016-07-01. Differences in perceived severity of Zika virus infection and dengue fever and its influence on mosquito control practices in Malaysia, a dengue-endemic country. https://doi.org/10.1101/061622

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