Abstract

Introduction: Chikungunya is a vector borne virus in alphaviridae family passed to humans by Aedes mosquito bite. Chikungunya virus has been transmitted by Aedesaegypti and Aedes Albopictus mosquitoes. Laboratory confirmation can be done via detection of CHIKV and anti-CHIKV antibody in blood samples. Because it is a risk group three pathogen, its containment is in biosafety level 3 facilities.

Objective: To determine factors associated with Chikungunya fever outbreak in Dolo ado district, Liben zone, Somali regional state, South-Eastern Ethiopia from June 10 to 17, 2016.

Methods: An unmatched case-control study design was used to investigate the outbreak from June 10 to 17, 2016. Epidemiological data were collected through face to face interview using structured questionnaire. Laboratory tests were performed all 17 serum samples using Real Time Reverse Transcriptase Polymerase Chain Reaction (rRT-PCR) technique. Results were displayed using texts, tables and graphs and statistical significance was interpreted using Odds ratio with 95% confidence interval and P value <0.05 after logistic regression was performed.

Result: In a multivariable analysis, failure to use long lasting impregnated net [AOR=14.6,(1.7-127.8), (p=0.015)], presence of Aedes mosquito larvae in water holding container during the investigation time [AOR=25.6(1.5-442.5), (p=0.025]) and travel history to Mandera (the neighboring Kenyan town) 2 weeks back from the date of onset of illness [AOR=37.3(4.3 - 321.3), (p=0.001)] were found associated with the disease. The odds of respondents who did not use bed nets while sleeping during daytime were 14.6 times more to have the disease than those who used bed nets. Basically, this finding is applicable for Aedesaegypti because it bites in the day time, and to the contrary using bed nets in a very hot weather may not be comfortable.

Conclusion: This investigation notes that Chikungunya has emerged in Ethiopia as additional cause of acute febrile illness. Vector control intervention, particularly, long lasting insecticide nets, indoor residual spray and larvicidal should be applied to halt the transmission. Continuous education should be offered for border crossing people to dress long sleeved clothes. Ministry of health of Ethiopia should recognize the disease as public health threat and prepare guideline, intervention strategy and reporting mechanism.

Keywords: Chikungunya; Virus; Outbreak; Ethiopia