title: Presence of respiratory viruses in equines in Brazil.
abstract: Equines are susceptible to respiratory viruses such as influenza and parainfluenza. Respiratory diseases have adversely impacted economies all over the world. This study was intended to determine the presence of influenza and parainfluenza viruses in unvaccinated horses from some regions of the state of São Paulo, Brazil. Blood serum collected from 72 equines of different towns in this state was tested by hemagglutination inhibition test to detect antibodies for both viruses using the corresponding antigens. About 98.6% (71) and 97.2% (70) of the equines responded with antibody protective titers (≥ 80 HIU/25µL) H7N7 and H3N8 subtypes of influenza A viruses, respectively. All horses (72) also responded with protective titers (≥ 80) HIU/25µL against the parainfluenza virus. The difference between mean antibody titers to H7N7 and H3N8 subtypes of influenza A viruses was not statistically significant (p > 0.05). The mean titers for influenza and parainfluenza viruses, on the other hand, showed a statistically significant difference (p < 0.001). These results indicate a better antibody response from equines to parainfluenza 3 virus than to the equine influenza viruses. No statistically significant differences in the responses against H7N7 and H3N8 subtypes of influenza A and parainfluenza 3 viruses were observed according to the gender (female, male) or the age (≤ 2 to 20 years-old) groups. This study provides evidence of the concomitant presence of two subtypes of the equine influenza A (H7N7 and H3N8) viruses and the parainfluenza 3 virus in equines in Brazil. Thus, it is advisable to vaccinate equines against these respiratory viruses.
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: Dalva Assunção Portari
authors.initials: DA
authors.lastname: Mancini
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: Aparecida Santo Pietro
authors.initials: AS
authors.lastname: Pereira
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: Rita Maria Zucatelli
authors.initials: RM
authors.lastname: Mendonça
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: Adelia Hiroko Nagamori
authors.initials: AH
authors.lastname: Kawamoto
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: Rosely Cabette Barbosa
authors.initials: RC
authors.lastname: Alves
authors.affiliation: Virology Laboratory, Division of Scientific Development, Butantan Institute, São Paulo, SP, Brazil.
authors.forename: José Ricardo
authors.initials: JR
authors.lastname: Pinto
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine and Zootechnics, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Enio
authors.initials: E
authors.lastname: Mori
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, Faculty of Veterinary Medicine and Zootechnics, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Leonardo José
authors.initials: LJ
authors.lastname: Richtzenhain
authors.affiliation: Department of Food Science and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Jorge
authors.initials: J
authors.lastname: Mancini-Filho
mesh_terms: D000367:Age Factors; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006734:Horse Diseases / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D006736:Horses; D053123:Influenza A Virus, H3N8 Subtype / Q000276:immunology*; D053126:Influenza A Virus, H7N7 Subtype / Q000276:immunology*; D008297:Male; D009976:Orthomyxoviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*
chemical_list: D000914:Antibodies, Viral