<p><strong>Background:&nbsp;</strong>Pertussis is a highly contagious vaccine-preventable bacterial infections that<br>affects all susceptible individuals, regardless of age.<strong> </strong>Despite the availability of effective vaccines, pertussis remains endemic with high fatality rates in low and middle-income countries. East Gojjam Zone health department reported 714 pertussis suspect case and three deaths in hard-to-reach Bibugn district of East Gojjam Zone on January 23,2023. Investigation was done to verify the existence of an outbreak, identifying the potential risk factors, and describe the epidemiology to prevent further similar outbreak.</p>