title: Rapid detection of Orthopoxvirus by semi-nested PCR directly from clinical specimens: a useful alternative for routine laboratories.
abstract: Orthopoxvirus (OPV) has been associated with worldwide exanthematic outbreaks, which have resulted in serious economic losses as well as impact on public health. Although the current classical and molecular methods are useful for the diagnosis of OPV, they are largely inaccessible to unsophisticated clinical laboratories. The major reason for the inaccessibility is that they require both virus isolation and DNA manipulation. In this report, a rapid, sensitive and low-cost semi-nested PCR method is described for the detection of OPV DNA directly from clinical specimens. A set of primers was designed to amplify the conserved OPV vgf gene. The most useful thermal and chemical conditions were selected and minimum non-inhibitory dilutions were determined. More than 100 Brazilian Vaccinia virus (VACV) field clinical specimens were tested using this semi-nested PCR in order to confirm its applicability. Cowpox virus was also detected by PCR from the ear scabs of scarified Balb/c mice. In addition, the method was highly sensitive for the detection of VACV DNA in murine blood and excreta, which are among the suggested reservoirs of OPV. Together, these data suggest that semi-nested PCR can be used for initial screening for OPV and as a routine diagnostic laboratory method.
authors.affiliation: Laboratório de Vírus, Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Jônatas Santos
authors.initials: JS
authors.lastname: Abrahão
authors.forename: Betânia Paiva
authors.initials: BP
authors.lastname: Drumond
authors.forename: Giliane de Souza
authors.initials: Gde S
authors.lastname: Trindade
authors.forename: André Tavares
authors.initials: AT
authors.lastname: da Silva-Fernandes
authors.forename: Jaqueline Maria Siqueira
authors.initials: JM
authors.lastname: Ferreira
authors.forename: Pedro Augusto
authors.initials: PA
authors.lastname: Alves
authors.forename: Rafael Kroon
authors.initials: RK
authors.lastname: Campos
authors.forename: Larissa
authors.initials: L
authors.lastname: Siqueira
authors.forename: Cláudio Antônio
authors.initials: CA
authors.lastname: Bonjardim
authors.forename: Paulo César Peregrino
authors.initials: PC
authors.lastname: Ferreira
authors.forename: Erna Geessien
authors.initials: EG
authors.lastname: Kroon
mesh_terms: D000818:Animals; D001938:Brazil; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis / Q000821:virology; D019411:Clinical Laboratory Techniques / Q000379:methods*; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D004195:Disease Models, Animal; D005814:Genes, Viral; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D018155:Orthopoxvirus / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011213:Poxviridae Infections / Q000175:diagnosis* / Q000662:veterinary* / Q000821:virology; D012680:Sensitivity and Specificity
chemical_list: D017931:DNA Primers; D004279:DNA, Viral