Epidemiology of laboratory confirmed measles virus cases in Amhara Regional State of Ethiopia, 2004-2014.

Background: Measles is a highly contagious viral infection causing large outbreaks all over the world. Despite the availability of safe and cost effective vaccine, measles remained endemic with persistent periodic outbreaks in the Horn of Africa. The aim of this study is to characterize laboratory confirmed measles cases in Amhara Regional State, which was one of the highly affected regions in Ethiopia.

Method: A suspected measles case was defined as any person presenting with fever, maculopapular rash and one or more of the three symptoms cough, coryza or conjunctivitis or a patient in whom a clinician suspects measles. A blood sample was collected for any measles suspected patient with a case based investigation form and specimen transported to the National Measles Laboratory in good condition where it was to be tested for Measles IgM antibody by ELISA technique. Data was entered and analyzed using Epi-Info 3.5.4 software.

Result: A total of 6579 samples were tested for measles IgM among 7296 samples collected in Amhara Regional State over 11 years (2004-2014). Of the tested samples, 2412 (36.7%) were found positive, while 3965 and 202 samples were found to be negative and equivocal (compatible) respectively. Patients with age ≥ 10 years were the most affected. The highest number of laboratory confirmed measles cases were detected in 2014 and cases were occurred in all of the 11 zones of the state. A seasonal peak was noted in the hot-dry season of the year.

Conclusion: Measles remains to be a public health problem in Amhara Regional State of Ethiopia, mostly affecting people ≥ 10 years of age. Measles virus was detected in all zones of the state, reaching its peak in the hot-dry season. To reduce the incidence of measles, it is highly recommended to improve routine immunization, and conduct a wide age group campaign. Additional research to evaluate the knowledge, attitudes and practices of the general population and health care professionals about measles infection and vaccination is important. Genotyping of circulating measles virus strain is recommended.