Trends and Geographical Distribution of Diphtheria in Nigeria: A Re-emerging Disease

Diphtheria is a highly contagious, deadly vaccine preventable bacterial infection that affect a person's nose, throat, and occasionally skin. Diptheria is fatal in 5-10% of cases, however, the Case fatality Rate (CFR) can be as high as 20% - 40% among children and unvaccinated adults. Currently the number of diptheria cases reported globally has being increasing gradually. Nigeria ranks number 6 in the list of countries by population with about 42.54% of its population below 14 years of age. Despite the availability of antitoxing vaccine in the country only 41.7% of children under 15 years of age were fully vaccinated, thereby making the country more vulnerable to the disease. The study therefore was aimed at examining the spread and trend of diphtheria disease in Nigeria from the onset of the major outbreak of the disease in December 2022. Data for the study were sourced from secondary sources. From December 2022 to January 2023 Nigeria recorded a total of 111 (42.1%) confirmed cases and 22 deaths with a case fatality rate for confirmed/probable cases of 19.8% in four States. Out of the 111 confirmed cases only a small percentage (10.8%) were vaccinated with diphtheria toxin-containing vaccine. Also majority (91.9%) of the confirmed cases occurred in children aged 2-14 years. Since then, there has been constant number of reported cases. As of 31 July 2023, the country recorded a total 1534 confirmed cases in 11 states and 137 death with a case fatality rate of 8.9%. Majority (66.4%) of the confirmed cases occurred among children aged 1-14 years with only 18.1% of the 1534 confirmed cases previously vaccinated. In this era of globalization if prompt action is not taken, diphtheria will become a major threat not only to Nigeria but also globally.