Egyptian rousette bats (ERBs) are reservoir hosts for the Marburg virus (MARV).
The immune dynamics and responses to MARV infection in ERBs are poorly understood, and
limited information exists on the role of antibodies in protection of ERBs against MARV infection.
Here, we determine the duration of maternal immunity to MARV in juvenile ERBs, and evaluate the
duration of the antibody response to MARV in bats naturally or experimentally infected with the virus.
We further explore whether antibodies in previously naturally exposed bats is fully protective against
experimental reinfection with MARV. Maternal immunity was lost in juvenile ERBs by 5 months of
age. Antibodies to MARV remained detectable in 67% of experimentally infected bats approximately
4 months post inoculation (p.i.), while antibodies to MARV remained present in 84% of naturally
exposed bats at least 11 months after capture. Reinfection of seropositive ERBs with MARV produced
an anamnestic response from day 5 p.i. Although PCR-defined viremia was present in 73.3% of
reinfected ERBs, replicating virus was recovered from the serum of only one bat on day 3 p.i. The
negative PCR results in the salivary glands, intestines, bladders and reproductive tracts of reinfected
bats, and the apparent absence of MARV in the majority of swabs collected from these bats suggest
that reinfection may only play a minor role in the transmission and maintenance of MARV amongst
ERBs in nature.