Modelling filovirus maintenance in nature by experimental transmission of Marburg virus between Egyptian rousette bats

Amy J Schuh,Jessica R Spengler,Brock E Martin,Jo Ann D Coleman-Mccray,Jonathan S Towner,Luke S Uebelhoer,Stuart T Nichol,Brian R Amman,Tara K Sealy,Megan E B Jones

doi:10.1038/ncomms14446

Abstract

The Egyptian rousette bat (ERB) is a natural reservoir host for Marburg virus (MARV); however, the mechanisms by which MARV is transmitted bat-to-bat and to other animals are unclear. Here we co-house MARV-inoculated donor ERBs with naive contact ERBs. MARV shedding is detected in oral, rectal and urine specimens from inoculated bats from 5–19 days post infection. Simultaneously, MARV is detected in oral specimens from contact bats, indicating oral exposure to the virus. In the late study phase, we provide evidence that MARV can be horizontally transmitted from inoculated to contact ERBs by finding MARV RNA in blood and oral specimens from contact bats, followed by MARV IgG antibodies in these same bats. This study demonstrates that MARV can be horizontally transmitted from inoculated to contact ERBs, thereby providing a model for filovirus maintenance in its natural reservoir host and a potential mechanism for virus spillover to other animals.

Highlights

The Egyptian rousette bat (ERB) is a natural reservoir host for Marburg virus (MARV); the mechanisms by which MARV is transmitted bat-to-bat and to other animals are unclear
The first study found that ERBs inoculated by the intraperitoneal and subcutaneous routes with the Vero cell-adapted, human-derived Hogan strain of MARV exhibited viral replication in multiple tissues in the absence of clinical disease followed by seroconversion, while ERBs inoculated by the oronasal route with the same virus showed no evidence of MARV infection within the 21-day specimen collection period[13]
Biological specimens obtained from the two negative control bats over the course of the study tested uniformly negative for MARV RNA and MARV IgG antibodies

Summary

Introduction

The Egyptian rousette bat (ERB) is a natural reservoir host for Marburg virus (MARV); the mechanisms by which MARV is transmitted bat-to-bat and to other animals are unclear. A second study using the low-passage, bat-derived 371 bat strain of MARV inoculated by the subcutaneous route demonstrated that infectious MARV was shed in oral secretions of experimentally infected ERB, indicating that the virus had potential to be horizontally transmitted between ERBs by the direct or indirect contact routes[14].

Results

Conclusion