Sunday 19 February 2023

Outbreak of Cholera in the eastern Democratic Republic of Congo.

On 14 December 2022, a Cholera epidemic was officially declared by the Governor of the North Kivu Province, in the Democratic Republic of Congo, following the isolation of Vibrio cholerae among 140 of 247 samples collected from suspected cases in the Nyiragongo Health Zone, according to a press release issued by the World Health Organization on 10 February 2023. As of 4 February 2023, a total of 4386 cholera cases (of which 1009 are laboratory-confirmed) with 16 deaths (a mortality rate of 0.4%) have been reported. Cholera is endemic in the eastern part of the Democratic Republic of the Congo, including Ituri, North Kivu, South Kivu, and Tanganyika provinces, with cases reported through the year. 

A multisectoral community-based response has been implemented, including a Cholera vaccination campaign. However, considering the fragile context in which this outbreak is taking place, ongoing armed conflicts with further displacements, concurrent epidemics, inadequate levels of access to health care, poor drinking water, hygienic and sanitary conditions, and population movements between the affected health zones and neighbouring countries (including Rwanda and Uganda), the World Health Organization assesses the risk posed by this outbreak as high at the national and regional level, and low at the global level.

Cholera is endemic in several provinces in the Democratic Republic of the Congo. However, from mid-November to the end of 2022, there has been an upsurge in the number of reported cholera cases in the health zones of Nyiragongo and Karisimbi, in the province of North Kivu. Since then, cases have shown a declining trend.

Number of Cholera cases (suspected and confirmed) reported in Nyiragongo and Karisimbi health zones. World Health Organization.

In Nyiragongo, the number of new Cholera cases (suspected and confirmed) increased from 51 in week 47 (21-27 November) to 556 cases in week 50 (12-18 December) of the year 2022, and to 683 cases in week 52 (26 December 2022- 1 January 2023). On 14 December 2022, a Cholera epidemic was officially declared by the Governor of North Kivu Province, following isolation of Vibrio cholerae in the stool of 140 cases from Nyiragongo Health Zone at the local laboratory in Goma.

As of 4 February 2023, a total of 4386 cholera cases (1009 laboratory-confirmed) with 16 deaths have been reported, of which 4011 (91.5%) are from Nyiragongo and 375 (8.5%) from Karisimbi. In the Nyiragongo Health Zone, the most affected age group is 5-14 years (30.1%), followed by 1-4 years (29.7%) and 15-29 years (16.6%); children under the age of one represent 8% of cases.

In total, 15 health areas including seven in the Nyiragongo Health Zone (Kanyaruchinya, Kibati, Kiziba, Mudja, Munigi, Ngangi III and Turunga) and eight in Karisimbi Health Zone (Baraka, Bujovu, Kasika, Katoyi, Majengo, Methodiste Mugunga and Muugano Solidarite) are currently affected by the Cholera epidemic.

In the Nyiragongo Health Zone, the Kanyaruchinya Health Area is the most affected, contributing to 73.3% of all suspected Cholera cases reported from Nyiragongo. In Karisimbi Health Zone, the Methodist Health Area is the most affected with 59.4% of all cases, followed by Baraka and Lasika health areas (both contributing to 7.3% of cases from Karisimbi Health Zone).

Cumulative number of Cholera cases (suspected and confirmed) by health area in Niyragongo and Karisimbi health zones, as of 4 February 2023. Nord Kivu Provincial Health Division/World Health Organization.

The cholera outbreak is principally affecting internally displaced populations, with 97% of the cases reported among internally displaced people in the Nyiragongo Health Zone, and 59% of cases among internally displaced people reported from the Methodist Health Area of Karisimbi Health Zone, which houses the Don Bosco Internally Displaced Population Camp. However, the outbreak is also spreading across the surrounding communities with nearly 3% of the cases in the Nyiragongo Health Zone and 41% of the cases in the Karisimbi Health Zone belonging to the host community.

Cholera is an acute enteric infection caused by ingesting the Bacterium Vibrio cholerae a Gram-negative, comma-shaped Gammaproteobacterium, related to other pathogenic Bacteria such as Yersinia pestis (Bubonic Plague), and Esherchia coli (food poisoning), which present in contaminated water or food. It is mainly linked to insufficient access to safe drinking water and inadequate sanitation. Cholera is an extremely virulent disease that can cause severe acute watery diarrhoea resulting in high morbidity and mortality, and can spread rapidly, depending on the frequency of exposure, the exposed population and the setting. Cholera affects both children and adults and can be fatal if untreated.

SEM image of Vibrio cholerae Bacteria. Kim et al. (2000).

The incubation period is between 12 hours and five days after ingestion of contaminated food or water. Most people infected with Vibrio cholerae do not develop any symptoms, although the bacteria are present in their faeces for 1-10 days after infection and are shed back into the environment, potentially infecting other people. The majority of people who develop symptoms have mild or moderate symptoms, while a minority develop acute watery diarrhoea and vomiting with severe dehydration. Cholera is an easily treatable disease. Most people can be treated successfully through prompt administration of oral rehydration solution.

The consequences of a Humanitarian crisis, such as disruption of water and sanitation systems, or the displacement of populations towards inadequate and overcrowded camps, can increase the risk of Cholera transmission, should the Bacteria be present or introduced. A multisectoral approach including a combination of surveillance, water, sanitation and hygiene, social mobilization, treatment, and oral Cholera vaccines is essential to control Cholera outbreaks and to reduce deaths.

Multisectoral coordination has been established at the provincial level, and daily coordination meetings are held in Kaniyaruchinya (Nyiragongo Health Zone). The incident management system was activated at the World Health Organization office. A budgeted preparedness and response plan has been developed and several partners are involved in the response, including the World Health Organization, which supports the Provincial Health Division in the implementation of the health sector response in collaboration with the Ministry of Health and the other partners, such as the United Nations High Commissioner for Refugees, International Organization for Migration, Médecins Sans Frontières, UNICEF, World Food Programme, and Save the Children.

surveillance and laboratory commission has been set up by the North Kivu Provincial Health Division with the support of the World Health Organization and other partners. Four data managers have been trained and equipped with computers by the World Health Organization. Training on case definition has been provided to healthcare workers and community health workers; investigation teams have also been trained on active case finding. Surveillance activities are ongoing, including active case finding, alert notification and investigation, and contact tracing and follow-up. Data is collected daily from Oral Rehydration Points, Cholera Treatment Units and Cholera Treatment Centers. Samples are regularly collected also from suspected cases registered outside the outbreak area in order to assess the extent of the epidemic. Data is analyzed on a daily basis and shared with partners for operational decision-making. The World Health Organization has also supported the National Biological Research Institute in Goma with sample transportation.

The World Health Organization and partners have supported the establishment of 56 Oral Rehydration Points in Internally Displaced Population sites, four Cholera Treatment Units (Kibati, Kanyarucinya, Kahembe, and Don Bosco) and two Cholera Treatment Centers (Munigi, Kiziba) in the most affected health areas, with a total capacity of 205 beds. The World Health Organization and partners also provided support for the free provision of basic health care in functional health structures in the two affected health zones to ensure the maintenance of essential health services for vulnerable populations.

An Infection Prevention and Control/Water, Hygiene and Sanitation commission has been set up by the North Kivu Provincial Health Division and supported by partners including the World Health Organization and UNICEF. Systematic decontamination of households and public spaces is implemented by trained teams. Training for safe and dignified burials is also carried out. In Internally Displaced Population sites a total of 1706 latrines, 293 showers, 91 hand-washing stations and 62 well sites have been established. Regular supply of water is made through cisterns. Training for healthcare workers and hygiene workers on Infection Prevention and Control practices is also carried out regularly.

Several advocacy meetings have been held with community leaders and political-administrative authorities. Community workers have been trained to raise awareness about cholera, and preventive measures are communicated door-to-door and during public meetings with the affected population.

At the national level, coordination meetings were organized to ensure the preparation of the vaccination campaign against Cholera in the two affected health zones. The World Health Organization provided support to the Ministry of Health for the mobilization from the vaccination International Coordination Group of 364 137 doses of oral cholera vaccines in the two affected health zones. With the support of the Global Alliance for Vaccines and Immunization, after its launch by the Governor of North Kivu Province on 25 January 2023, the Oral Cholera Vaccination campaign in three health zones of North Kivu Provincial Health Division (including in Internally Displaced Population sites) took place between 25-30 January 2023 and immunized 351 207 people aged one year and older out of a target of 364 137, giving a coverage of 96.4%.

Cholera is endemic in parts of Democratic Republic of Congo. In 2022, according to data from the National Integrated Disease Surveillance and Response System, a total of 18 403 suspected cases of cholera, including 302 deaths (a fatality rate of 1.6%), were notified in the Democratic Republic of Congo, in 104 health zones in 19 of the 26 provinces of the country.

However, the current epidemic is showing a rapid upsurge in a fragile context, with high risk environments such as Internally Displaced Population camps. For years, the Democratic Republic of Congo has been experiencing several armed and community conflicts, particularly in the east, putting the country in a state of unprecedented Humanitarian and health crisis.

Due to internal armed clashes, which intensified in 2022, nearly 450 857 new Internally Displaced Persons arrived in North Kivu (which already hosts 1.9 million Internally Displaced people). Of them, 53.4% (240 579) are hosted in the territory of Nyiragongo and particularly 97.7% (235 111) in Internally Displaced Population sites, which are characterized by overcrowding, poor hygiene and sanitation conditions, very limited access to drinking water, latrines and basic health services. In addition, population movements are regularly observed between the affected health zones and the other health zones in the province of North Kivu as well as the rest of the country, where the populations also have limited access to drinking water, good hygiene and sanitation conditions, as well as to health care facilities. Moreover, the current rainy season may favor the spread of the epidemic in other health zones.

With the ongoing armed conflicts, displacements are likely to continue, leading to a worsening of the Humanitarian context and the vulnerabilities of the populations, including the need for basic social services. All this is evolving in a context of a fragile health system; recurrent attacks on hospital infrastructures and reduced availability of services. Other outbreaks are also ongoing (COVID-19, Yellow Fever, Poliomyelitis, Measles, Monkeypox, Meningitis, etc.) and there are extremely limited Human, material and financial resources.

The risk of Cholera spreading to neighboring countries cannot be ruled out. Indeed, there are population movements between the affected health zones and neighboring countries, including Rwanda and Uganda.

The affected health zones border the city of Goma, which has an international airport. Countries in the Great Lakes sub-region (Rwanda, Uganda, Burundi), which are most at risk of Cholera importation from the current epidemic hotspots in North Kivu, have inadequate levels of access to health care, poor drinking water, hygienic and sanitary conditions. A Cholera epidemic is also ongoing in Burundi with 120 suspected cases and 1 death reported as of 7 February 2023. This epidemic affects the city of Bujumbura, which is located on the shores of Lake Tanganyika on the border with South Kivu, with population movements across the border.

The outbreak is occurring against a backdrop of a surge in Cholera outbreaks globally, which has constrained the availability of vaccines, tests, and treatments. Considering the above-described scenario, the World Health Organization assesses the risk posed by this outbreak as high at the national and regional level, and low at the global level.

The World Health Organization advises that a multi-pronged approach is essential to combat Cholera and reduce mortality. The measures used combine surveillance, improvement of water supply, sanitation and hygiene, social mobilization, treatment of the disease and oral Cholera vaccines. Countries affected by Cholera are advised to strengthen disease surveillance and national preparedness to rapidly detect and respond to possible outbreaks.

The World Health Organization recommends improving access to proper and timely case management of Cholera cases, improving access to safe drinking water and sanitation infrastructure, as well as improving infection prevention and control in healthcare facilities. These measures along with the promotion of preventive hygiene practices and food safety in affected communities are the most effective means of controlling Cholera. Effective risk communication and community engagement strategies are needed to encourage behavioral change and the adoption of appropriate preventive measures.

Measures aimed at improving environmental conditions include applying long-term sustainable solutions for water supply, sanitation and hygiene in Cholera-prone areas. In addition to Cholera, these interventions can also prevent a wide range of other water-borne diseases and contribute to achieving goals in education and the fight against poverty and malnutrition. Solutions for water supply, sanitation and hygiene related to cholera are in line with the Sustainable Development Goals.

Rapid access to treatment is essential during a Cholera outbreak. Oral rehydration should be available in communities and not just in larger health centers that can offer intravenous infusions and management at any time. With rapid and appropriate care, the case fatality rate should remain below 1%.

Community mobilization must continue as an integral part of the response and should cover information on the symptoms of Cholera, on the precautions to take to protect against the disease, and the need to promptly seek care when symptoms appear.

The oral Cholera vaccines should be used in conjunction with improvements in water and sanitation to control Cholera outbreaks and for prevention in targeted areas known to be at high risk for Cholera.

The World Health Organization recommends Member States to strengthen and maintain surveillance for Cholera, especially at the community level, for the early detection of suspected cases and to provide adequate treatment and prevent its spread. Early and adequate treatment limits the mortality rate of patients to less than 1%.

The World Health Organization does not recommend any travel or trade restrictions to the Democratic Republic of Congo based on the currently available information.

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