Undiagnosed disease - Democratic Republic of the Congo

Between 24 October and 5 December 2024, Panzi health zone in Kwango Province of Democratic Republic of the Congo recorded 406 cases of an undiagnosed disease with symptoms of fever, headache, cough, runny nose and body ache. All severe cases were reported to be severely malnourished. Among the cases, 31 deaths have been registered. The majority of cases reported are among children, particularly those under five years of age. The area is rural and remote, with access further hindered by the ongoing rainy season. Reaching it from Kinshasa by road takes an estimated 48 hours. These challenges, coupled with limited diagnostics in the region, have delayed the identification of the underlying cause. Rapid response teams have been deployed to identify the cause of the outbreak and strengthen the response. The teams are collecting samples for laboratory testing, providing a more detailed clinical characterization of the detected cases, investigating the transmission dynamics, and actively searching for additional cases, both within health facilities and at the community level. The teams are also aiding with the treatment of patients, risk communication and community engagement. Given the clinical presentation and symptoms reported, and a number of associated deaths, acute pneumonia, influenza, COVID-19, measles and malaria are being considered as potential causal factors with malnutrition as a contributing factor. Malaria is a common disease in this area, and it may be causing or contributing to the cases. Laboratory tests are underway to determine the exact cause. At this stage, it is also possible that more than one disease is contributing to the cases and deaths.

On 29 November 2024, the Ministry of Public Health of the Democratic Republic of the Congo reported to WHO an alert regarding increased deaths from an undiagnosed cause in Panzi health zone.

Between 24 October and as of 5 December 2024, Panzi health zone in Kwango Province has recorded 406 cases of an undiagnosed disease with symptoms of fever, headache, cough, runny nose and body ache and 31 deaths (Case Fatality Ratio or CFR of 7.6%).  The reported cases had a peak in epidemiological week 45 (week ending 9 November 2024). The outbreak is still ongoing. According to a press briefing by the Ministry of Health on 5 December, there have been several additional deaths outside of health facilities (community deaths). These deaths still need to be investigated, characterized (age, gender etc) and verified.

Cases have been reported from nine out of 30 health areas in Panzi health zone: Kahumbulu, Kambandambi, Kanzangi, Kasanji, Kiama, Mbanza Kipungu, Makitapanzi, Mwini ngulu, and Tsakala Panzi. The majority of cases (95.8%) are reported from Tsakala Panzi (169), Makitapanzi (142) and  Kanzangi (78) health areas.

In Panzi health zone, children aged 0-14 years represent 64.3% of all reported cases, with the age groups 0-59 months, 5-9 years, and 10-14 years accounting for 53%, 7.4%, and 3.9% of cases, respectively. Females constitute 59.9% of the total cases. Among the deaths, 71% are below the age of 15, with 54.8% of the total in children under the age of five years. All severe cases were reported to be malnourished. There are 145 cases aged 15 and above, of which nine died (CFR: 6.2%). Deaths have primarily occurred in the village communities.

The area experienced deterioration in food insecurity in recent months, has low vaccination coverage and very limited access to diagnostics and quality case management. There is a lack of supplies and transportation means and shortage of health staff in the area. Malaria control measures are very limited.

The clinical presentation of patients includes symptoms such as fever (96.5%), cough (87.9%), fatigue (60.9%) and a running nose (57.8%). The main symptoms associated with death include difficulty in breathing, anaemia, and signs of acute malnutrition. Based on the current context of the affected area and the broad presentation of symptoms, a number of suspected diseases need to be ruled out through further investigations and laboratory testing. These include but are not limited to measles, influenza, acute pneumonia (respiratory tract infection), hemolytic uremic syndrome from E. coli, COVID-19, and malaria. 

1. Leadership and coordination:

• Coordination has been strengthened at the national, provincial, and community levels. On 30 November 2024, the first Public Health Emergency Operations Center (PHEOC) meeting was held with all partners to address the alert, after which a rapid response team (RRT) from Kwango Province was deployed to Panzi. On 3 December 2024, a second PHEOC meeting was convened with partners, leading to the decision to deploy a national-level RRT to Panzi with support from WHO. 
• Daily coordination meetings are being held at the national level, with provincial teams actively participating in ongoing planning and response.
  

2.  Surveillance:

• A case definition has been developed based on clinical symptoms observed, which is guiding surveillance and reporting efforts.  
• Active case search is being conducted in health facilities, including reviews of hospital registers to identify additional cases. Investigations and active case search are also being organized in the community. 
• Data collection is ongoing, focusing on the preparation of a line list and detailed epidemiological analysis.  
• Community deaths are being investigated to better understand transmission dynamics and the scope of the outbreak.  

3.  Case Management:

• A provincial RRT was deployed to Panzi on 30 November, and a multidisciplinary RRT from the national level, including WHO experts, was deployed on 7 December to investigate the outbreak, and reinforce the response.  
• The teams are carrying medication to support case management and prevent more deaths.
• Efforts are underway to strengthen capacity of healthcare providers to ensure the best possible care for patients. 

4.  Laboratory:

• Laboratory equipment was transported to collect samples from cases and send for testing at INRB in Kinshasa. Additionally, RDTs for malaria and COVID-19 have been provided to assist in diagnosis. 

5.  Risk communication and community engagement:

• Key messages have been developed to enhance public awareness and encourage general preventive behaviors. These messages are being disseminated through community engagement, with sensitization campaigns underway. 

6.  Infection prevention and control:

• Infection prevention and control measures are being reinforced. Health and care workers have been briefed on key practices, including the proper use of masks, hand washing, and gloves, to reduce the risk of further transmission. 

7.  Logistics

• Logistical support is being provided for effective case management, including the transportation of samples to INRB Kinshasa for laboratory testing. Health facilities and hospitals in the most affected health areas are being supplied with appropriate medications and sampling kits to support the response. 

There are ongoing efforts to address the outbreak in Panzi health zone, however significant challenges in the clinical and epidemiological response remain, that increase the public health risk for the affected population. Severe cases with anaemia, respiratory distress, and malnutrition have been reported. The affected area is remote, complicating the assessment and response.  The Integrated Food Security Phase Classification (IPC) for acute food insecurity levels in Kwango province increased from IPC 1 (acceptable) in April 2024 to IPC 3 (Crisis Level) in September 2024. This suggests a significant phase of increase in food insecurity and risk of severe acute malnutrition.

Symptoms such as fever, cough, headache, and body ache have been observed since 24 October, primarily through health worker reports, yet Integrated Disease Surveillance and Response (IDSR) data on baseline respiratory illness rates are not available for affected health zone to establish trends. Cases have been reported in family clusters, suggesting potential transmission dynamics within households, though additional investigation is needed. Furthermore, there is no information available on specific vaccination coverage, including childhood vaccination, in the affected health zone, leading to uncertainties about vaccine-deprived population immunity. 

Gaps in case management have also been identified. Stock-outs of medications for treating common diseases frequently occur, and care is not provided free of charge, which could limit access to treatment for vulnerable populations.  

The affected area’s remoteness and logistical barriers, including a two-day road journey from Kinshasa due to the rainy season affecting the roads and limited mobile phone and internet network coverage across the health areas, have hampered the rapid deployment of response teams and resources. Furthermore, there is no functional laboratory in the health zone or province, requiring the collection and shipment of samples to Kinshasa for analysis. This has delayed diagnosis and response efforts. The lack of sample collection supplies has further limited diagnostic capacity, leaving significant gaps in understanding the outbreak’s aetiology. 

Insecurity in the region adds another layer of complexity to the response. The potential for attacks by armed groups poses a direct risk to response teams and communities, which could further disrupt the response. 

Based on the above rationale, the overall risk level to the affected communities is assessed as high.

At the national level, the risk is considered moderate due to the localized nature of the outbreak within the Panzi health zone in Kwango province. However, the potential for spread to neighboring areas, coupled with gaps in surveillance and response systems, this assessment underscores the need for heightened preparedness. 

At the regional and global levels, the risk remains low at this time. However, the proximity of the affected area to the border with Angola raises concerns about potential cross-border transmission, and continued monitoring and cross-border coordination will be essential to mitigate this risk. 

The current confidence in the available information remains moderate, as significant gaps in clinical, epidemiological, and laboratory data persist.

To reduce the impact of the outbreak in the Panzi health zone and mitigate further spread, WHO advises the following measures:  

Strengthening coordination mechanisms at all levels—national, provincial, zonal, and local—is critical for a unified response. Enhanced communication infrastructure, such as satellite phones, is required to overcome the limited network coverage in affected areas. Cross-border collaboration with Angola is also crucial to monitor for similar cases and prevent potential cross-border transmission.  

Improving surveillance efforts is a priority to identify and respond to cases promptly. Active case searches should continue in both health facilities and communities, with a particular focus on areas reporting deaths and family clusters. Community-based surveillance must be strengthened to ensure early case detection and rapid response.

Careful characterization of the clinical syndrome and outcomes and an improved case definition based on the information collected will be necessary to understand the situation. In particular, data which clarify possibility of coinfection and multiple pathologies, and uncertainties in outcomes among vulnerable groups should be collected. The WHO has established the Global Clinical Platform to provide rapid turnaround of structured data analysis using anonymized case records; its use is recommended in the detailed capture of patient syndromes and outcomes. 

Effective case management requires ensuring an adequate supply of essential medications to support treatment and prevent more deaths. RDTs for malaria should be distributed to facilitate differential diagnosis, while laboratory testing must be expedited through the shipment of samples to INRB Kinshasa to confirm or rule out suspected causes, including COVID-19 and influenza. Long-term laboratory capacity strengthening, and decentralization will be important in provision of diagnostic capability in the affected health zone.  

Infection prevention and control (IPC) measures must be reinforced across all health facilities. Healthcare workers should receive training on IPC practices, including the proper use of personal protective equipment (PPE) such as masks and gloves, as well as strict hand hygiene protocols. These measures will reduce transmission risks within health facilities and improve the safety of healthcare delivery.  

Risk communication and community engagement are essential to raising public awareness. Targeted messages should be disseminated to educate the public on respiratory illness symptoms, preventive measures, and the importance of seeking care early. Community leaders must be engaged to build trust and encourage adherence to public health guidance. Addressing misinformation and fears within the community is critical to ensuring effective collaboration in the response.  

Logistical and security challenges also require attention. Strengthening logistical support for the deployment of teams and supplies will ensure timely access to affected areas. Contingency plans should be developed to address potential insecurity posed by armed groups, safeguarding response personnel and maintaining continuity in response activities.  

Further investigations are needed to clarify whether anaemia observed in severe cases is linked to the outbreak. The main hypothesis of respiratory illness should be validated by studying its relationship with seasonal influenza and other potential factors. Additionally, historical outbreaks, such as that of typhoid fever which was reported in the health zone two years ago, should be reviewed to identify recurring vulnerabilities that may inform current response efforts. In addition, understanding general malnutrition rates and identifying cases of acute malnutrition in the affected population can inform appropriate nutritional care and prevent further deaths.  

• Democratic Republic of the Congo Ministry of Health Press Release: https://x.com/i/broadcasts/1YqGovjjrwAKv?s=09 
• Democratic Republic of the Congo: Acute Malnutrition Situation For July - December 2024 and Projection for January - June 2025 https://www.ipcinfo.org/ipc-country-analysis/details-map/en/c/1157190/?iso3=COD  

Citable reference: World Health Organization (8 December 2024). Disease Outbreak News; Undiagnosed disease – Democratic Republic of the Congo. Available at: https://www.who.int/emergencies/disease-outbreak-news/item/2024-DON546