The past diphtheria epidemic in the newly independent states of the former USSR: Situation, causes, and lessons learned

The 1990s witnessed a dramatic resurgence of diphtheria in the Newly Independent States (NIS) of the former Soviet Union, culminating in the largest epidemic of the vaccine era to date. This crisis, with over 140,000 cases and 4,000–5,000 deaths reported between 1990 and 1998, not only reversed decades of progress but also provided critical lessons for global infectious disease control. The following summary synthesizes the epidemic’s trajectory, with a focus on its causes, as described in two seminal articles by Dittmann and colleagues.  Epidemic overview and spread  The epidemic began in the Russian Federation in 1990, rapidly spreading to all 15 NIS and the Baltic States by the end of 1994. The outbreak peaked in 1994–1995, with annual incidences as high as 73 cases per 100,000 in Tajikistan. Russia alone accounted for three-quarters of all cases. The epidemic was not confined to the NIS; importations into Finland, Germany, Norway, Poland, and Mongolia...