Related Experiment Video
Updated: Nov 19, 2025
Use of In vivo Imaging to Monitor the Progression of Experimental Mouse Cytomegalovirus Infection in Neonates
Published on: July 6, 2013
Mastomys natalensis is a possible natural rodent reservoir for encephalomyocarditis virus
Mai Kishimoto1, Bernard M Hang'ombe2,3, William W Hall4,5,6,7
1Division of Molecular Pathobiology, Research Center for Zoonosis Control, Hokkaido University, Sapporo, Japan.
Abstract:
Encephalomyocarditis virus (EMCV) infects a wide range of hosts and can cause encephalitis, myocarditis, reproductive disorders and diabetes mellitus in selected mammalian species. As for humans, EMCV infection seems to occur by the contact with animals and can cause febrile illnesses in some infected patients. Here we isolated EMCV strain ZM12/14 from a natal multimammate mouse (Mastomys natalensis: M. natalensis) in Zambia. Pairwise sequence similarity of the ZM12/14 P1 region consisting of antigenic capsid proteins showed the highest similarity of nucleotide (80.7 %) and amino acid (96.2%) sequence with EMCV serotype 1 (EMCV-1). Phylogenetic analysis revealed that ZM12/14 clustered into EMCV-1 at the P1 and P3 regions but segregated from known EMCV strains at the P2 region, suggesting a unique evolutionary history. Reverse transcription PCR (RT-PCR) screening and neutralizing antibody assays for EMCV were performed using collected tissues and serum from various rodents (n=179) captured in different areas in Zambia. We detected the EMCV genome in 19 M. natalensis (19/179=10.6 %) and neutralizing antibody for EMCV in 33 M. natalensis (33/179=18.4 %). However, we did not detect either the genome or neutralizing antibody in other rodent species. High neutralizing antibody litres (≧320) were observed in both RT-PCR-negative and -positive animals. Inoculation of ZM12/14 caused asymptomatic persistent infection in BALB/c mice with high antibody titres and high viral loads in some organs, consistent with the above epidemiological results. This study is the first report of the isolation of EMCV in Zambia, suggesting that M. natalensis may play a role as a natural reservoir of infection.
Insights
Encephalomyocarditis virus (EMCV) was isolated from natal multimammate mice in Zambia. These mice may serve as a natural reservoir for EMCV, a virus that can cause illness in mammals and potentially humans.
Area of Science:
- Virology
- Zoonotic diseases
- Rodent-borne pathogens
Background:
- Encephalomyocarditis virus (EMCV) infects diverse mammals, causing significant health issues.
- Human EMCV infections are linked to animal contact, often presenting as febrile illnesses.
- The epidemiology and reservoirs of EMCV in Africa remain incompletely understood.
Purpose of the Study:
- To isolate and characterize Encephalomyocarditis virus (EMCV) from rodents in Zambia.
- To investigate the prevalence of EMCV infection and antibodies in Zambian rodent populations.
- To identify potential natural reservoirs of EMCV in the region.
Main Methods:
- Isolation and genetic sequencing of EMCV strain ZM12/14 from Mastomys natalensis.
- Phylogenetic analysis of the EMCV ZM12/14 strain.
- Reverse transcription PCR (RT-PCR) and neutralizing antibody assays on rodent samples (n=179).
Main Results:
- EMCV strain ZM12/14 was isolated from Mastomys natalensis, showing unique phylogenetic characteristics.
- The EMCV genome was detected in 10.6% and neutralizing antibodies in 18.4% of M. natalensis sampled.
- No evidence of EMCV infection or antibodies was found in other rodent species examined.
- Asymptomatic persistent infection was observed in experimentally inoculated BALB/c mice.
Conclusions:
- This study reports the first isolation of EMCV in Zambia.
- Mastmys natalensis (natal multimammate mouse) is identified as a potential natural reservoir for EMCV.
- The findings highlight the importance of rodent surveillance for zoonotic viral diseases.
