Nigeria officials issue nationwide alert over cholera, yellow fever and dengue fever due to flood season
The Nigerian Meteorological Agency (NiMet) recently issued an impact-based weather forecast for July 2025, highlighting several states at heightened risk of flooding and flash floods. Sokoto state was identified as having a particularly high risk of flash flooding. Other states at notable flood risk include Kaduna, Zamfara, Yobe and a couple of other states.
Flash floods can lead to large-scale displacement of populations, disruption of livelihoods, and increased risk of infectious disease outbreaks especially waterborne and vector-borne diseases.
Floodwaters often contaminate our water sources by washing pathogens or germs from soil, animal waste, or overwhelmed sewage systems into rivers, lakes, and other bodies of water. This contamination affects drinking water sources and creates ideal conditions for the spread of cholera, which is caused by the bacterium Vibrio cholerae.
Additionally, heavy rainfall or flooding can create stagnant water in natural and artificial receptacles such as puddles, tree holes, discarded tires and containers which becomes ideal breeding sites for mosquitoes that transmit diseases such as malaria, yellow fever, and dengue fever.
Nigeria is already experiencing a rising incidence of cholera, while yellow fever and dengue fever are beginning to be detected in some states. This is also occurring at a time when the country is contending with ongoing outbreaks of Mpox and diphtheria.
In response to the rising risks and threats, the Nigeria Centre for Disease Control and Prevention (NCDC) wishes to inform the public and stakeholders of its ongoing, coordinated national response to recent surges in these infectious disease outbreaks.
The NCDC is working closely with state governments, health partners, and communities to strengthen surveillance, provide treatment supplies, deploy rapid response teams, and other communication and community engagement efforts to contain outbreaks and reduce their impact.
Cholera
Cholera is a life-threatening disease that causes severe acute watery diarrhea, which can lead to rapid dehydration.
It affects both children and adults. Symptoms typically appear between 12 hours and 5 days after exposure and, if not treated promptly, the disease can result in death within hours.
It is transmitted by consuming food or water contaminated with the bacterium Vibrio cholerae. Heavy rains can wash the bacteria into drinking water supplies.
As of Epidemiological Week 26 (23rd – 29th June 2025), 34 states have reported cases, with Zamfara State accounting
for 32% of all suspected cases. Other states with high case numbers include Bayelsa, Adamawa, Delta, Lagos, and Rivers.
Yellow Fever and Dengue Fever
Yellow fever and dengue fever are mosquito-borne viral diseases that pose a growing public health concern in Nigeria.
They are transmitted primarily by the Aedes species. Preventing mosquito bites and eliminating breeding sites are key to reducing the spread of both diseases.
Yellow Fever
Yellow fever is an epidemic-prone disease and vaccination is the most effective measure for prevention. The yellow fever vaccine is safe, affordable, and a single dose provides life-long protection. Ensuring high vaccination coverage is critical to preventing outbreaks and saving lives.
As of 2025, suspected yellow fever cases have been reported across the country, with seven confirmed cases in six states: Abia, Anambra, Edo, Ekiti, Lagos, and Rivers. A single confirmed case of yellow fever is considered an outbreak. No deaths have been recorded to date.
The NCDC is working to strengthen laboratory diagnostics, surveillance, and field investigations in affected states, and continues to collaborate with the National Primary Health Care Development Agency (NPHCDA) to support state authorities with mass vaccination campaigns.
Subscribe to Outbreak News TV on YouTube
Dengue Fever
The NCDC has confirmed an outbreak of dengue fever in Edo State between June 9th and 13th, 2025. The outbreak was confirmed through laboratory testing and underscores the growing risk posed by vector-borne diseases.
In collaboration with the Edo State Ministry of Health, NCDC is leading response efforts, including enhanced surveillance, risk communication, mosquito control, and clinical management support.
Residents are advised to look out for symptoms such as high fever, headache, muscle or joint pain, sore throat, and swollen glands. Prompt medical attention is essential.
To prevent infection from mosquito-borne diseases such as yellow fever and dengue fever, the NCDC urges the public to:
• Eliminate mosquito breeding sites by clearing stagnant water and covering water storage containers.
• Use personal protective measures such as insect repellents, insecticide-treated nets, and long-sleeved clothing.
• Get vaccinated against yellow fever, which remains the most effective prevention method.
• Improve infrastructure and sanitation, including drainage systems, to prevent water accumulation and reduce mosquito breeding.
• Seek prompt medical attention if you experience symptoms such as fever, headache, joint pain and avoid self -medication as symptoms could mimic malaria.
Healthcare workers are advised to maintain a high index of suspicion for dengue in febrile patients, implement appropriate infection prevention and control measures, and promptly notify local and state epidemiologists, as dengue is a notifiable disease in Nigeria by law.