Ebola Virus Causes Intestinal Tract Architectural Disruption and Bacterial Invasion in Non-Human Primates

Area of Science:

• Veterinary Pathology
• Infectious Diseases
• Gastroenterology

Background:

• The 2014-2016 West Africa Ebola Virus (EBOV) outbreak raised concerns about secondary gastrointestinal bacterial infections.
• Empiric antibiotic treatment was common due to these concerns.

Purpose of the Study:

• To summarize gastrointestinal pathology in control non-human primates (NHPs) within an EBOV infection model.
• To characterize the pathological effects of EBOV on the gastrointestinal tract.

Main Methods:

• Retrospective pathology case series.
• Examination of 31 rhesus macaques in an EBOV-Kikwit intramuscular infection model.
• Immunofluorescence assays to detect EBOV antigen.

Main Results:

• All NHPs showed lymphoid depletion in gut-associated lymphoid tissue (GALT).
• Mesenteric lymphoid depletion and necrosis occurred in 87% of NHPs.
• Mucosal barrier disruption, necrosis, ulceration, and hemorrhage were observed in the intestinal tract.
• Focal bacterial submucosal invasion was noted in 29% of NHPs.
• EBOV antigen was detected in macrophages and endothelial cells in areas of GI vascular injury.

Conclusions:

• EBOV infection causes significant gastrointestinal pathology in NHPs, including GALT lymphoid depletion and mucosal damage.
• The findings support concerns regarding secondary bacterial infections in EBOV patients.
• EBOV directly impacts the GI tract, affecting immune cells and vascular structures.