#16,114
Yesterday, we saw the WHO's announcement on West Africa's first case of the Marburg Virus - a virus with similar impacts as Ebola - via a press release from WHO AFRO.
While rare, Marburg was the first of the filovirus family of hemorrhagic diseases to be recognized. Normally only found in parts of eastern and central Africa, Marburg – surprisingly - was first detected in Germany in the late 1960s.
In 1967, several workers involved with Polio research at a laboratory in Marburg, Germany fell ill with an unknown illness. What began with fever, vomiting, and diarrhea progressed rapidly to internal bleeding, shock, and for 7 of the 31 victims, death.
This lead to the creation of a new virus family; the Filoviridae, of which Marburg and the six known Ebola viruses are the principal members.An investigation identified the source of the virus: Green monkeys imported from Uganda for research, and in time, the virus was isolated.
- For the next three decades, the virus only showed up sporadically. In South Africa in 1975 (3 cases), Kenya in 1980 (2 cases) and again in 1987 (1 case), and in a pair of laboratory accidents in the Soviet Union in 1988 and 1990.
- Between 1998 and 2000 more than 150 cases were recorded in the Democratic Republic of the Congo, and a second marburgvirus (RAVV) was identified.
- In 2004-2005, the largest known outbreak occurred in Angola, where 90% of the 252 cases died. This from the CDC’s MMWR in 2005.
- And over the past 10 years we've seen several outbreaks in Uganda (see here, here and here).
Marburg's expansion to West Africa - which follows a similar path to Ebola, which arrived in Guinea in 2013 and sparked a major regional epidemic - is obviously a serious concern.
The good news is that so far, only 1 case has been identified, and none of his contacts have tested positive.
But based on Marburg's known virulence, and the demonstrated ability of Ebola to sweep through more urbanized West African communities, the WHO believes this case represents a high risk at the national level, requiring an immediate and coordinated response with support from international partners.
Overnight the WHO published a lengthy update and risk assessment (see below). I've only reproduced some excerpts, so follow the link to read it in its entirety.
Marburg virus disease - Guinea
9 August 2021
On 6 August 2021, the Ministry of Health of Guinea informed WHO of a confirmed case of Marburg virus disease (MVD) in Guéckédou Prefecture, Nzérékoré Region, south-western Guinea. The village where the case resided is near both Sierra Leone and Liberian borders. This is the first known case of Marburg virus disease in Guinea and in West Africa.
The case, a male, had onset of symptoms on 25 July. On 1 August he attended a small health facility near his village of residence with symptoms of fever, headache, fatigue, abdominal pain, and gingival hemorrhage. A rapid diagnostic test for malaria was performed which was negative. The patient received supportive care with rehydration, parenteral antibiotics and treatment to manage symptoms.
On 2 August 2021, he died in the community and an alert was raised by the sub-prefecture public health care facility to the prefectorial department of health in Guéckédou. Following the alert, an investigation team comprosed of national authorities and WHO experts was deployed to conduct an in-depth investigation. The team collected a post-mortem oral swab sample, which was sent the same day to the viral haemorrhagic fever reference laboratory in Guéckédou.On 3 August a real-time PCR was conducted which confirmed the sample was positive for Marburg virus disease and negative for Ebola virus disease. On 5 August the National Reference Laboratory in Conakry provided confirmation by real-time PCR of the positive Marburg result and on 9 August Institut Pasteur Dakar in Senegal provided reconfirmation that the result was positive for Marburg virus disease and negative for Ebola virus disease.
Public health response
The Ministry of Health (MoH) together with WHO, US Centers for Disease Control and Prevention, ALIMA, Red Cross, UNICEF, The International Organization for Migration and other partners, have initiated measures to control the outbreak and prevent further spread. Contact tracing is ongoing, along with active case searching in health facilities and at the community level. Three family members and a healthcare worker were identified as high-risk close contacts and their health is being monitored.The most recent Ebola virus disease (EVD) outbreak in Guinea was declared over on 19 June 2021 and a network of community health workers was set up as part of this recent outbreak along with a WHO technical team which has remained in country to support the government’s implementation of a post-EVD plan to enhance disease surveillance. This team has now been repurposed to support the government’s response activities to this outbreak of Marburg.The MoH has activated the national and district emergency management committees to coordinate the response including:
- A public health emergency operations center has been activated and a base to support response workers will be set up in the sub-prefecture of Koundou.
- An in-depth epidemiological investigation is being conducted around the confirmed case to identify the source of the outbreak: to date, a total of 146 contacts were identified and as of 8 August, 145 contacts have been followed-up.
- Active searching for suspected cases in the community and health facilities is ongoing.
- A surveillance team has been deployed and briefings for health workers are underway, with particular focus on the village where the index case was identified along with villages within a 15 kilometer radius.
- Point of entry surveillance is being reinforced and two health control entry points were recently revitalized (Kiesseneye and Nongoa). The three main entry points with Sierra Leone and Liberia are active and the others are under evaluation.
- In collaboration with ALIMA, there is an ongoing assessment of the case management capacity in the health facilities.
- Risk communication activities are ongoing in the community.
- Infection prevention and control activities (IPC) are ongoing and briefing sessions are being conducted on IPC and water and sanitation hygiene (WASH) standards in Koundou health center, along with information sessions for the population of Temessadou Mboket village volunteers on safe and dignified burials
WHO risk assessment
Marburg virus disease (MVD) is a highly virulent, epidemic-prone disease associated with high case fatality rates (CFR 24-90%). In the early course of the disease, clinical diagnosis of MVD is difficult to distinguish from other tropical febrile illnesses, because of the similarities in the clinical symptoms. Differential diagnoses to be excluded include, Ebola virus disease, as well as malaria, typhoid fever, leptospirosis, rickettsial infection, and plague. MVD is transmitted by direct contact with the blood, bodily fluids and/or tissues of infected persons or wild animals (e.g. monkeys and fruit bats).
Currently, there is no specific therapeutic or drug approved for MVD. Nevertheless, supportive care including: close monitoring of vital signs, fluid resuscitation, electrolyte and acid base monitoring along with management of co-infections and organ dysfunction, are critical components of care and optimize patient outcomes and survival. Some monoclonal antibodies (Mabs) are under development and other antivirals are being explored for MVD (e.g. Galidesvir, Favipiravir, Remdesivir) as part of clinical trials, but without clear results in the current moment more evidence and further studies are required. However, these should only be used as part of a randomized controlled trial.
As of 7 August, only one case has been confirmed and all four identified high-risk close contacts are asymptomatic. Investigations are ongoing to identify the source of the infection and additional contacts of the index case.
Guinea has previous experience in managing recurring viral hemorrhagic diseases such as EVD and Lassa fever, but this is the first time that MVD has been reported. The country has a fragile healthcare system which is further exacerbated by multiple disease outbreaks, recurrent epidemics and the COVID-19 pandemic. The response activities to recent outbreaks such as EVD, COVID-19 and Lassa fever likely contributed to early detection and response to Marburg Virus Disease in Guinea.
Guinea’s health authorities have responded rapidly to this event, and measures are being quickly implemented to control the outbreak. The affected village is in a remote forested area located near the border with Sierra Leone and Liberia. Cross-border population movement and community mixing between Guinea and neighboring Sierra Leone and Liberia may increase the risk of cross-border spread and as such, the Ministry of Health and Sanitation has proactively assessed the situation together with stakeholders and the district health leadership in Kono and Kailahun districts of Sierra Leone have been alerted. Health authorities in Sierra Leone and Liberia have activated contingency plans and have started public health measures at the points of entry with Guinea. Additionally the potential transmission of the virus between bat colonies and humans also pose an increased risk for cross-border spread.
These factors suggest a high risk at the national level, requiring an immediate and coordinated response with support from international partners. The risk at the regional level is high, based on the fact that the Guéckédou prefecture is well connected to Liberia and Sierra Leone, although authorities are already taking action. The risk associated with the event at the global level is low.
