In March 2024, Nigeria reported cases of suspected heavy metal poisoning in Sokoto State. About a month later, neighboring Zamfara State reported similar incidents, prompting an investigation by the Nigeria CDC on May 20, 2024, which led to the activation of the Emergency Operations Centre (EOC) for an effective response.
Heavy metal poisoning occurs when metals like lead or mercury accumulate in the body, often from contaminated water, soil, or food sources. Symptoms can include abdominal pain, vomiting, and neurological issues, with children being particularly vulnerable.
As of epidemiological week 23, 847 suspected cases had been reported, with 95 confirmed and 42 deaths, resulting in a Case Fatality Rate of 5.0%. The majority, 697 (82.3%), of the suspected cases were children aged 0-14.
The Nigeria CDC has been supporting both states in the response, deploying Rapid Response Teams (RRTs) and building the capacity of state-level RRTs. On June 18, 2024, the Nigeria CDC redeployed personnel to Sokoto and Zamfara States to actively identify and document cases and determine the true incidence and scope of the outbreak by training and engaging surveillance volunteers for case identification.
Leveraging the Africa CDC mandate to support public health initiatives of Member States and strengthen the capacity of their public health institutions, Dr. Herilinda Temba, Acting Regional Director of the Western Africa Regional Coordinating Centre, deployed two in-country Africa CDC epidemiologists on June 19, 2024, to support the Nigeria CDC and state situation assessment teams in Sokoto.
The ongoing response, including active case searches across Sokoto (15 Local Government Areas) and Zamfara (9 LGAs) between June 21 and June 27, identified some suspected cases that are under further investigation. During the same period, active case searches were conducted in the neighboring states of Katsina, Kaduna, Kebbi, and Niger by their respective state teams. “The search focused on communities and health facilities using a community case definition of any person with stomach swelling, pain, or vomiting that started in the last three months,” said Dr. Okoro Nwenyi, an epidemiologist working for Africa CDC in Nigeria, adding that findings from the search are yet to be finalized.
Africa CDC has been at the forefront of the response in the affected states, providing technical support to the EOC established by the Nigeria CDC across various pillars. The team assisted in developing a protocol for a case-control study to understand the drivers of the outbreak. They also supported the training of community informants deployed ward-by-ward for active case searches. Field supportive supervision and engagement with local community gatekeepers were carried out in two LGAs of Sokoto State. These activities are ongoing, providing much-needed support to state health authorities in Sokoto. “This support from Africa CDC to Nigeria CDC is supplementary to other outbreak response efforts and EOC management for diseases such as COVID-19, Lassa fever, cerebrospinal meningitis, cholera, diphtheria, measles, Mpox, and yellow fever,” said Dr. Temba.
