Mpox Found in North Carolina Sewage: What to Know
April 24, 2025
North Carolina health officials are urging vigilance after clade I mpox virus was detected in wastewater samples from Greenville, signaling possible undiagnosed or unreported infections. The findings, uncovered through the state’s wastewater monitoring network, mark the first environmental detection of this more virulent mpox strain in the state. Although no confirmed clade I cases have been reported in North Carolina to date, officials stress the importance of monitoring symptoms and considering vaccination among high-risk groups. This alert underscores wastewater surveillance as an essential tool for early detection and community-level awareness in preventing potential mpox transmission.
The North Carolina Department of Health and Human Services (NCDHHS) has issued a public alert following the detection of clade I mpox virus in wastewater samples collected from a treatment plant in Greenville on March 25, March 28, and April 8. The presence of viral particles was identified by the North Carolina Wastewater Monitoring Network, a statewide surveillance system established in 2021 to track the spread of high-concern pathogens like SARS-CoV-2 and influenza. These findings suggest that an undiagnosed or unreported clade I mpox case may have been present in the area, even though no clinical cases have yet been confirmed.
Clade I is the more virulent genetic subtype of mpox, historically associated with higher mortality rates than clade II, which was responsible for the 2022–2023 global outbreak. To date, only four clade I cases have been reported in the U.S. Early symptoms of mpox include fever, fatigue, headache, and a sore throat, progressing to a characteristic rash that evolves into scabs over two to three weeks. Infected individuals remain contagious until the rash fully resolves.
This discovery highlights the critical role of environmental surveillance in early detection and public health preparedness. With two clade II mpox cases already confirmed in North Carolina this year, health authorities are urging providers to remain vigilant for symptoms and encouraging high-risk individuals to get vaccinated. Secretary of Health Dev Sangvai emphasized that while the public risk remains low, proactive measures such as early diagnosis and immunization are essential to limiting community spread.
As mpox transmission patterns evolve and clade I continues to surface globally, this development serves as a timely reminder for both clinicians and the public to remain informed and prepared for emerging infectious threats.