Enhancing Capacity for Case Detection and Diagnosis of Febrile Zoonotic-Related Cutaneous Lesions in Georgia
Abstract
In June of 2013, two herders presented at a local clinic with severe febrile rash illness. The Poxvirus team from CDC Atlanta was notified and identified the causative agent as a previously undescribed Orthopoxvirus (OPXV). While the virus was initially found to have DNA-level signatures consistent with an OPXV, species level tests validated for identification of known zoonotic OPXV yielded negative or inconclusive findings. Amplification and sequencing of a DNA target generally conserved among OPXV suggested the virus was a new OPXV species. Subsequently, the virus was grown in cell culture and virus DNA was submitted for genome sequencing. The genomic data confirmed that the isolate represents a new, early divergent Eurasian OPXV species which is clearly distinct from all currently recognized OPXV. The position of this virus in the phylogeny indicates that it is a member of a separate virus clade within the genus, suggesting there are several other such species which have yet to be discovered. Human anthrax cases have also been identified in these regions and it is possible that the similarity of the disease presentation (severe febrile rash illness) caused by this OPXV, could be confused with cutaneous anthrax. To investigate this possibility, NCDC and CDC tested a limited set of samples from suspected anthrax cases where anthrax had been ruled out. From these samples, we detected and isolated a second OPXV which is again distinct from previous OPXV species but similar to the isolate obtained from Akhmeta. The patient was presumably infected near Vani, more than 200km from the Akhmeta case. The second isolate confirms that OPXV have been causing unrecognized infections across Georgia for at least several years. In addition to this, a rodent survey performed in 1986 resulted in the isolation an OPXV (then identified as cowpox virus) from the southeastern border of Georgia (Tsanava et al. 1989). Although it was clearly identified as an OPXV species, the isolate is no longer available but could possibly represent a third member of this newly identified OPXV clade. In June of 2013, two herders presented at a local clinic with severe febrile rash illness. The Poxvirus team from CDC Atlanta was notified and identified the causative agent as a previously undescribed Orthopoxvirus (OPXV). While the virus was initially found to have DNA-level signatures consistent with an OPXV, species level tests validated for identification of known zoonotic OPXV yielded negative or inconclusive findings. Amplification and sequencing of a DNA target generally conserved among OPXV suggested the virus was a new OPXV species. The genomic data confirmed that the isolate represents a new, early divergent Eurasian OPXV species which is clearly distinct from all currently recognized OPXV. The position of this virus in the phylogeny indicates that it is a member of a separate virus clade within the genus, suggesting there are several other such species which have yet to be discovered. The primary goals of this effort are to 1) build capacity for technical skills related to the detection and diagnosis of poxviruses and 2) establish a surveillance system for febrile rash illnesses in Georgia. This project will result in the establishment of diagnostic tools and surveillance systems for OPXV infection in humans and animals in Georgia. This will be achieved through capacity enhancements and training for case detection and diagnosis using state of the art OPXV diagnostic platforms (technology transferred from CDC Atlanta SMEs). An important feature of the work will be its emphasis on laboratory biosafety and biosecurity. In addition, this project will foster utilization of prior investments. For example this work will entail use of next-Generation Sequencing (NGS), which is already well established at the Lugar Center, but here we will further its application through the introduction of new techniques for phylogenetic analyses.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 26, 2016
- Source ID
- HDTRA11510066
Entities
People
- Ekaterine Khamaladze
Organizations
- Defense Threat Reduction Agency
- National Center for Disease Control and Public Health