Isolation and Characterization of Akhmeta Virus from Wild-Caught Rodents ( Apodemus spp.) in Georgia

Abstract

Akhmeta virus is a unique Orthopoxvirus that was described in 2013 from the country of Georgia. This paper presents the first isolation of this virus from small mammal (Rodentia; Apodemus spp.) samples and the molecular characterization of those isolates. The identification of the virus in small mammals is an essential component to understanding the natural history of this virus and its transmission to human populations and could guide public health interventions in Georgia. Akhmeta virus genomes harbor evidence suggestive of recombination with a variety of other orthopoxviruses; this has implications for the evolution of orthopoxviruses, their ability to infect mammalian hosts, and their ability to adapt to novel host species.

Laboratory Infection of Novel Akhmeta Virus in CAST/EiJ Mice

“…Skin lesions are a major site of replication and viral shedding for most OPXVs and potentially for AKMV as well. AKMV transmission in nature at this point is unknown, however, skin lesions collected from wild caught Apodemus flavicollis and Apodemus uralensis in the country of Georgia have had a mean viral load of 6 × 10 4 pfu/mL (range: 4 × 10 1 –1 × 10 5 pfu/mL) [ 5 ].…”

“…Further field and/or laboratory studies are needed to understand the capability of Mus musculus to serve as a liaison host in the country of Georgia. Future AKMV characterization studies should consider evaluating pathogenicity in multiple mouse strains, or perhaps infecting wild-caught mice such as Apodemus species, as members of this genus are evidenced to be potential reservoirs of AKMV in Georgia [ 5 ].…”

“…The primary exception to this ‘rule’ is Variola virus (the causative agent of smallpox), which was highly specialized as a human-only pathogen, making its eradication possible following immense global public health vaccination campaigns [ 2 ]. In recent years, new potential mammalian hosts of OPXVs have been identified [ 3 , 4 , 5 , 6 , 7 ] and an increasing number of novel OPXVs are being detected, including Akhmeta virus (AKMV) from the country of Georgia [ 8 , 9 , 10 , 11 , 12 ].…”

“…Additionally, 35.3% ( n = 34) of the small mammals collected in the same area showed IgG antibodies against OPXVs. Beginning in 2015, ecological investigations were conducted in several regions of Georgia to understand the circulation of the virus in its natural hosts/reservoirs [ 5 ]. These investigations suggest the virus has a broad geographic distribution in Georgia and have yielded five viral isolates from lesion and heart/lung material collected from sylvatic rodents of the genus Apodemus [ 5 ].…”

Here, There, and Everywhere: The Wide Host Range and Geographic Distribution of Zoonotic Orthopoxviruses

“…Infection with any orthopoxvirus is considered to generate protection against exposure or re- exposure to any other member of the genus [ 14 , 15 ]. Orthopoxvirus species are named primarily according to the hosts from which they were first isolated and identified; however, the name does not necessarily represents its natural reservoir or complete host range [ 8 , 16 , 17 , 18 , 19 ]. Despite the large number of studies, little is known about the primary hosts and reservoirs of zoonotic orthopoxviruses in nature, or their transmission and maintenance cycles [ 20 ].…”