Species determination of Brazilian mammals implicated in the epidemiology of rabies based on the control region of mitochondrial DNA

Abstract

Identification of animals that are decomposing or have been run over or burnt and cannot be visually identified is a problem in the surveillance and control of infectious diseases. Many of these animals are wild and represent a valuable source of information for epidemiologic research as they may be carriers of an infectious agent. This article discusses the results obtained using a method for identifying mammals genetically by sequencing their mitochondrial DNA control region. Fourteen species were analyzed and identified. These included the main reservoirs and transmitters of rabies virus, namely, canids, chiroptera and primates. The results prove that this method of genetic identification is both efficient and simple and that it can be used in the surveillance of infectious diseases which includes mammals in their epidemiologic cycle, such as rabies. Key-Words: Mitochondrial DNA, sequencing, identification, mammals, rabies.Different causative agents of infectious diseases are transmitted by wild or domestic mammals. The transmitting species are very often also wild reservoirs for the pathogen, and identification of these species is essential for an understanding of the epidemiologic cycles of the disease so that effective surveillance and control can be put in place [1]. Rabies is an example of a zoonosis in which the causative agent, the Rabies virus, can be transmitted by many species of mammals, some of which, such as chiroptera and wild canids, are wild reservoirs [2]. A large number of other zoonoses, such as hantavirus diseases, yellow fever and dengue, in which various mammals act as wild reservoirs for the etiologic agent, are also known [1].As methods for controlling mammals that transmit infectious agents in urban centers are now well understood, efforts can be concentrated on developing effective and ecologically correct methods to handle and control wild vectors and reservoirs. If this objective is to be achieved, it is important to know which animals are involved in the disease and which are the terminal hosts.For various reasons, including principles related both to ethics and animal conservation, obtaining wild animals is both difficult and expensive. However, many studies can be carried out with dead animals, particularly those that are run over on highways, and many researchers have taken advantage of this possibility.In recent decades, great strides have been made in the use of molecular biology methods based on nucleic acids, and sequencing of mitochondrial DNA (mtDNA) continues to be used intensively for the genetic identification of species [3][4][5].Certain mtDNA genetic markers, such as the mtDNA control region (D-loop) and the cytochrome b gene, are the most frequently used. Many of the genetic sequences of these two areas of mtDNA can be found in public domain websites, such as GenBank (http://www.ncbi.nlm.nih.gov/sites/entrez). Analyzing the mtDNA D-loop region and epidemiologic data, Carnieli et al. (2008) [6] found that the main wild canid involved in rabies in Northeast Brazil is ...

Exposure to rabies virus in a population of free-ranging capuchin monkeys (Cebus apella nigritus) in a fragmented, environmentally protected area in southeastern Brazil

“…In Brazil, rabies virus isolated from herbivores indicates that these isolates belong to the same lineage as the virus circulating among vampire bats (Desmodus rotundus), which are currently the primary reservoir of the virus in Latin America , and the isolates from wild canids, with the lineage of the virus circulating in domestic and wild dogs (Carnieli et al 2006(Carnieli et al , 2008a. However, bats are distributed throughout the State of São Paulo and are considered to be the primary animal responsible for transmission of rabies; in northeastern Brazil, in addition to bats, the virus is maintained in populations of wild canids (Cerdocyon thous) and common marmosets (Callithrix jacchus), and Carnieli et al (2008b) identified the genus Cebus, which can transmit the rabies virus in Brazil. In Santa Teresa Forest, bats, wild canids, and marmosets are the reservoir of rabies virus.…”

“…These findings of the rabies antibodies in apparently healthy monkeys are very interesting for further studies to better understand the dynamics of the infection in capuchin monkeys. In northern and northeastern Brazil, nonhuman primates are of great importance in the wild cycle of rabies transmission (Morais et al 2000;Carnieli et al 2008b), occasionally transmitting the disease to humans (Brasil 2008;Funasa 2010). Evidence of circulating rabies virus was found in capuchin monkeys in the State of São Paulo, and human exposure to animals serologically positive for rabies is a potential public health problem.…”

Sequenciamento parcial do gene Citocromo C oxidase (COI) para determinação de espécies de morcegos enviados para diagnóstico de raiva no Instituto Pasteur

“…Os genes mitocondriais têm sido utilizados como ferramentas moleculares para identificação genética, sistemática e evolução (HEBERT et al, 2003). Genes como citocromo B (CytB) e a região controle (D-loop) têm sido comumente utilizados (CARNIELI et al, 2008). Dentre esses genes, podemos destacar ainda o citocromo C oxidase subunidade I (COI) que consiste em um marcador já estabelecido para estudos de identificação de espécies conhecidas e para o descobrimento de novas espécies (SHARMA; KOBAYASHI, 2014).…”

Microarray for Identification of the Chiropteran Host Species of Rabies Virus in Canada

“…To address these issues a recent study, which generated barcodes for 260 bat specimens representing 13 Canadian bat species, proposed the use of COI barcoding methods to improve species identification of submitted specimens [29]. Similar strategies involving sequence determination of other mitochondrial loci have been applied to confirm the nature of rabies reservoir species in Latin America [30], and to expand knowledge of the epidemiology of bat lyssaviruses in Europe [31]. However, to facilitate routine use of such an approach in a diagnostic setting it was determined that a highly automated method which could be applied by analysts not expert in complex molecular biology techniques would be highly valuable.…”