Acute respiratory tract infections (ARTIs) are a significant public health concern, particularly in vulnerable populations. In February 2025, an outbreak of ARI was reported in Tarbey village, Banisa Sub-County, Mandera County, prompting an urgent epidemiological investigation. A total of 108 cases were initially reported, with symptoms including fever, cough, dehydration, and body weakness. By February 22, 2025, the case count had risen to 151, with three fatalities (case fatality rate: 2%). Given the rapid spread, a multidisciplinary team from the Kenya Field Epidemiology and Laboratory Training Program (FELTP), National Public Health Laboratories (NPHL), Kenya Red Cross, and county health representatives was deployed by the Ministry of Health to determine the outbreak's cause, transmission patterns, and risk factors.

Key objectives of the investigation included assessing the outbreak’s magnitude, identifying the causative pathogen, and implementing preventive and control measures to curb further transmission. The findings will contribute to strengthening outbreak preparedness and response efforts.