Skipping of animals to humans triggers fatal Marburg outbreak

Skipping of animals to humans triggers fatal Marburg outbreak

The third largest outbreak in the history of Deadly Marburg-Virus was done by A single jump of the pathogen from animals to humans show the first genomic evidence.

The outbreak began last month in Rwanda, where 63 people were infected, 15 of whom died. Further indications indicate that the first person who infected itself as part of the outbreak is probably during a visit to a cave that houses a bat type that carries the virus.

Multiple transmissions from animals to humans have aroused fear that the virus in Rwanda has been more common than previously assumed. In addition, an unclear origin of the virus could have increased the prospect of new outbreaks.

Rwanda's reaction to the virus has also contributed to keeping the outbreak within limits, researchers report. Scientists praise the country's efforts to control the outbreak, to examine its origins and to share data with the scientific community. "As soon as you have recognized that there was a problem, you have initiated the tracking, carried out a thorough epidemiological examination, identified [first] patients and possibly found the source of infection-and within a week a Test test with an experimental vaccine , says Angela Rasmussen, virologist at the University of Saskatchewan in SaskatchoN, Canada. This shows that in the Marburg virus disease "a quick and urgent reaction can alleviate the severity of the outbreak," she adds.

The knowledge that has not yet been published in full or in peer review, were published on the social platform X and during a media appointment on October 20th.

fast containment

The outbreak called on September 27th is Rwanda's first ; Tanzania and Equatorial Guinea recorded their first outbreaks of Marburg last year, and Ghane had his first 2022 outbursts-the high fever, Severe diarrhea, nausea and vomiting and, in severe cases, occur to nasal or gum bleeding-occasionally occurring about once a year, while they usually only determined a few times a year before the 2020s were.

Since the beginning of the outbreak, the reports about new infections have decreased significantly. Rwandic health officers have recorded a new case and no deaths in the past 10 days, and only two people remain in isolation and treatment. A Marburg outbreak can be declared an end if 42 consecutive days have not been reported to new cases.

There is no proven vaccine or treatment for infections with the virus, is closely related to the Ebola virus , both in its symptoms and in its transmission, which is mainly made by contact with body liquids. Health authorities offer a candidate vaccine, manufactured by the Sabin Vaccine Institute in Washington DC, the contacts of infected persons. So far, more than 1,200 doses have been administered.

This outbreak has one of the lowest mortality rates - about 24% - for Marburg that has ever been recorded; Previous outbreaks reported on mortality rates of up to 90%. This is probably the result of faster diagnoses, access to medical care and the fact that most infections occurred in relatively young health specialists.

of individual origin

To support the containment of the outbreak, researchers of the Rwanda Biomedical Center in Kigali The genome of the Marburg-Virus of several infected persons sequenced. They found that all samples were very similar, which indicates that the virus was quickly spread in a short time and that they had a common origin. They also discovered that the virus tribe is closely related to one that was detected in Uganda in 2014, as well as with one who was found in bats in 2009, reports Yvan Buttera, Rwanda's Minister of State for Health, who was involved in research.

A comparison of the tribe of 2014 with the one that causes the current outbreak shows a "limited mutation rate," says Betera, indicating that there have probably only been a few changes in the transferability or lethality of the virus in the past ten years. In general, viruses collect mutations as they multiply over time; If it applies that the mutation rate is low, Rasmussen wonders how the virus in its animal reservoir- The Egyptian fruit bat (Rousettus Aegyptiacus) -without any significant changes.

researchers indicate that Environmental threats such as climate change and deforestation have increased the likelihood that people affect animals that can transmit infections . More data about how the virus persisted in bats-and in which tissues-could help to sensitize the surveillance measures, which means that the health authorities could get a better picture of virus hotspots, adds Rasmussen.

Buttera explains that the genomic analyzes are completed; He and his colleagues hope to share the full data by the end of the week.