outbreak at a glance
Two fatal cases of Marburg virus disease (MVD) have been reported from Ashanti District, Ghana. On 28 June 2022, these cases were notified to the health authorities as suspected cases of Viral Hemorrhagic Fever (VHF) and tested positive for Marburg virus on 1 July 2022. The MVD was first notified in Ghana. An MVD outbreak can pose a serious public health threat because it is dangerous and often fatal.
Description of the outbreak
On 28 June 2022, health authorities in the Ashanti District of Ghana were notified of two suspected cases of viral hemorrhagic fever (Fig. 1). This region is located in the middle belt of Ghana and is the most populous region of the country.
The first case was a 26-year-old male who was a farm worker in Adansi North District, Ashanti District, with a travel history to Western District. Before the onset of symptoms on June 24, he arrived from the Western Region in the Ashanti Region. He sought care in a hospital on June 26 and died on June 27. The case was transferred and buried in the Swala Tuna Kalba region, in the Savannah region bordering Burkina Faso and Côte d’Ivoire. The burial took place before the results of the MVD lab tests came out.
The second case is a 51-year-old man who worked on a farm in Bkwai Municipality, Ashanti Region. He sought care in the same hospital as the first case on June 28 but died the same day.
Both conditions are accompanied by fever, general malaise, nose and mouth bleeding, and subconjunctival hemorrhage (bleeding from blood vessels in the eye). Blood samples were collected on June 27 for the first case and June 28 for the second case and sent to the Noguchi Memorial Institute of Medicine Research (NMIMR) for testing. On July 1, both cases were confirmed to be infected with Marburg virus by reverse transcriptase polymerase chain reaction (RT-PCR). On July 12, samples collected from the two cases were sent to the Institut Pasteur in Dakar, Senegal (IPD) which confirmed the results from NMIMR on July 14, 2022.
Figure 1. The area of the two confirmed Marburg virus disease cases reported in Ghana, as of 20 July 2022
The source of infection is unknown. Preliminary investigations showed that none of these cases had a history of contact with dead animals, sick animals or animals and had not attended any social gathering within three weeks of onset of symptoms. Although both cases were farmers, they worked in different locations, and no epidemiological link was found between them. However, both cases came from communities living in a forest environment.
A cumulative number of 108 individuals (50 from Ashanti District, 48 from Savannah District, 10 from Western District) were identified as contacts of the two cases, all of whom were under quarantine and daily observation for 21 days. On July 20, all contacts completed their follow-up period. These contacts included health care workers and immediate family members of the cases. A contact reported some symptoms, but the blood sample collected tested negative for NMIMR on July 7. All other contacts were reported to be in good health during the follow-up period.
MVD is an epidemic-prone disease and is associated with a high mortality rate (CFR; 24-88%). In the early stage of the disease, the clinical diagnosis of MVD is difficult to distinguish from many other tropical fever diseases due to similarities in clinical symptoms. Other hemorrhagic fevers, particularly Ebola virus disease, should be excluded, as well as malaria, typhoid fever, leptospirosis, rickettsial infections, and plague. Human MVD infection can result from prolonged exposure to mines or caves inhabited by Rousettus bat colonies. Marburg virus is spread through human-to-human transmission by direct contact (through broken skin or mucous membranes) with blood, secretions, organs, or other body fluids of infected people, and with surfaces and materials (such as bedding and clothing) contaminated with blood. these fluids.
Although there are no approved vaccines or antiviral treatments to treat the virus, supportive care — rehydration with oral or intravenous fluids — and treatment for specific symptoms, improves survival. A range of potential treatments are being evaluated, including blood products, immunotherapies, and drug treatments.
The risks of this outbreak are high at the national level, moderate at the regional level, and low at the global level. The notification of two confirmed cases of MVD with a CFR of 100% (2/2) is concerning. The epidemiological investigation has not yet identified the source of this outbreak, highlighting the need to intensify community surveillance.
There is a risk of this outbreak spreading to neighboring countries because the first case traveled from the Western Region before symptoms appeared. The western region shares a border with Côte d’Ivoire, and this could present the risk of cross-border transmission if more cases continue to be reported or affect other regions. In addition, the first case was not buried safely in the Savannah region bordering Côte d’Ivoire and Burkina Faso. Therefore, the WHO has assessed the risk of this outbreak as high at the national level, moderate at the regional level, and low at the global level.
Community engagement activities should be implemented in the three identified regions of Ghana (Ashanti, Savannah and Western Regions) with a particular focus on providing adequate information and support to the population to implement measures to prevent further transmission and avoid stigmatization within the community, and to encourage early introduction of treatment centers and other outbreak containment measures necessary, including safe burial.
It is also important to raise awareness of the risk factors for MVD infection and the preventive measures that individuals can take to reduce human exposure to the virus. Key public health communication messages include:
- Reducing the risk of human-to-human transmission in the community resulting from direct or close contact with infected patients, especially their body fluids. Close physical contact with Marburg patients should be avoided. Gloves and appropriate personal protective equipment should be worn when caring for patients at home. Hands should be washed regularly after visiting sick relatives in the hospital, as well as after caring for the sick at home.
- Reduce the risk of transmission from bats to humans. Handle wildlife with gloves and other appropriate protective clothing. Thoroughly cook animal products (blood and meat) before consumption and avoid eating raw meat. During work, research activities, or tourist visits in mines or caves inhabited by fruit bat colonies, wear gloves and other appropriate protective clothing including masks.
Containment measures should be continued and strengthened in the three regions of Ghana. These measures include:
- Maintaining and building trust with communities
- Expansion of surveillance activities (active case finding, contact monitoring, investigation)
- Examine all suspected cases of MVD in time
- Ensure that appropriate infection prevention and control measures are implemented when caring for suspected, probable and confirmed patients
- Early isolation and care of suspected and confirmed cases, if possible, in designated health facilities with trained health workers and appropriate measures to prevent fungal infection.
- Conduct a safe and dignified burial for deceased individuals who are likely or confirmed to have the coronavirus.
Transmission of Marburg virus in healthcare settings has previously been reported when appropriate infection prevention and control (IPC) measures were not implemented. IPC measures to reduce transmission risks in healthcare include:
- Establish an IPC task force in the health district to ensure the implementation of infection prevention and control activities
- Ensure health workers are briefed on MVD (Standard and Transmission Based Precautions) including focus on safe injection practices
- Ensure minimum requirements and capacities for water, sanitation, hygiene and insulation in health facilities.
Based on the current risk assessment, WHO advises against any restrictions on travel and trade to Ghana.