The Ebola outbreak in the Democratic Republic of the Congo may have been circulating for months before being officially declared on May 15, as health authorities face criticism over delays in detection and response.

The first known case was a healthcare worker in Ituri province who developed symptoms in late April, but reports of unexplained deaths in the Mongbwalu area had already emerged weeks earlier. Researchers suggest transmission may have begun as early as February. Genetic analyses cited by the World Health Organization (WHO) also point to the outbreak starting around that time.

The WHO warned that the delay in detection continues to increase the risk of transmission, particularly in communities affected by insecurity, population displacement, overcrowding, and poor access to healthcare. As of September 7, the WHO reported more than 6,700 confirmed cases in the Democratic Republic of the Congo and over 3,200 deaths in the country, with cases also recorded in Uganda and France.