Suspected Chicken Pox Outbreak Investigation and Response in Yirga Chefe Town, Ethiopia, August 2018

Introduction: Chicken pox or varicella is an acute viral infectious disease of childhood caused by varicella-zoster virus. Humans are the only known hosts for this virus. The major route of transmission is airborne, however, transmissions via aerosols or direct contact with blister fluid have also been reported. The primary infection presents as fever and exanthematous rash. Clinically apparent infection usually provides lifelong immunity. The disease is usually acute and self-limiting but occasionally can lead to secondary infections like pneumonia, encephalitis, and secondary bacterial infections. Varicella is vaccine preventable disease. An estimated 4.2 million cases and 4200 deaths occur annually worldwide. This outbreak investigation was conducted to describe chicken pox cases in terms of person, place and time from 6th to 18th August 2018. Methods: We conducted a descriptive study in the Yirga cheffe town. We line listed all reported cases which contains sociodemographic characteristics and signs and symptoms of patients. We have also visited the reporting internally displaced population (IDP) sites during investigation. The line listed data were analyzed with person, place and time. Cases were treated symptomatically in mobile clinics. Results: A total of 25 suspected cases of chicken pox were reported between 6th and 18th of August 2018 from Yirga cheffe town IDP sites. The cases were reported from two IDP sites. Out of the total reported cases 14 (56%) were males while the remaining 11 (44%) were females with regard to sex. 88% of the total reported cases were children under the age of fifteen. Conclusion: The most affected age group in this outbreak was under the age of fifteen. Males were more affected than females in this outbreak. Unavailability of chicken pox vaccine in Ethiopia might be a risk for the occurrence of this outbreak. Strengthening routine surveillance in the IDP sites is recommended. Ministry of Health of Ethiopia should consider the introduction of chicken pox vaccine in the country. Ministry of Health should prepare guidelines and manuals for response of outbreaks.