Flávia Mello Viegas

Flávia Mello Viegas

*This is an algorithmically generated author record based on publicly available information.

Flávia Mello Viegas has a total of 42 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Botulism in a Dog Fed a Raw Meat-Based Diet: A Case Report

    by Flávia Mello Viegas, Poliane de Fátima Oliveira, Marina Carvalho Oliveira Campos, Marina Mendes Santiago Fernandes, Alexandra Oliveira Abreu, Clara Berquo Cascaes, João Victor Ferreira Campos, Rodrigo Otávio Silveira Silva

    Raw meat-based diets (RMBDs) have become increasingly popular among pet owners, despite well-documented risks of contamination with pathogenic bacteria capable of causing severe illness in companion animals. This report describes a fatal case of botulism in a 3-year-old female Labrador Retriever weighing 37 kg that was fed exclusively RMBD. The dog presented with acute-onset flaccid paralysis of the limbs approximately 48 h after possible ingestion of decomposing raw meat discarded in household waste. Supportive therapy, including fluid administration, nutritional support and eventual mechanical ventilation was provided. However, the patient developed progressive respiratory failure and died. The presence of Clostridium botulinum type C neurotoxin was confirmed in the dog serum by neutralization test in mice. The case suggests RMBD as a potential source of botulism toxins, particularly when derived from improperly stored meat products. The findings underscore the importance of detailed dietary history in dogs presenting with acute flaccid paralysis and reinforce the need for heightened awareness regarding the microbiological risks associated with raw feeding practices.

  • Open Access

    Occurrence and characterization of methicillin-resistant Staphylococcus spp. in diseased dogs in Brazil

    by Flávia Mello Viegas, Jordana Almeida Santana, Brendhal Almeida Silva, Rafael Gariglio Clark Xavier, Cláudia Teixeira Bonisson, Júlia Lara Sette Câmara, Mário Cesar Rennó, João Luis Reis Cunha, Henrique César Pereira Figueiredo, Francisco Carlos Faria Lobato, et al.

    Staphylococcus pseudintermediusis a major commensal bacterium of the skin and mucosae of dogs and an opportunistic agent responsible for several clinical infections, such as pyoderma, otitis, and surgical wound infections. The emergence of methicillin-resistantS.pseudintermedius(MRSP) has become a problem of great concern in veterinary and human medicine because it is multidrug resistant (MDR) and can also infect humans. This study aimed to identify the occurrence ofStaphylococcusspp. in infected patients and investigate the antimicrobial resistance profiles and molecular structure of MRSP isolates. Samples were obtained from two different veterinary clinics; suggestive colonies were submitted to matrix-assisted laser desorption ionization-time of flight (MALDI-ToF) mass spectrometry and confirmed at the species level by polymerase chain reaction (PCR). Sequencing of the16S rRNAandrpoBgenes were used in selected samples that were not identified by MALDI-ToF and by the species-specific PCR. Antimicrobial susceptibility and PCR detection ofmecAwere performed. MRSP isolates were subjected to multilocus sequence typing. Of all the clinical staphylococci (n = 131), 98 (74.8%) were identified asS.pseudintermedius. Multidrug resistance (resistance to ≥3 classes of antimicrobials) was observed in 63.2% ofS.pseudintermediusisolates, and 24.5% ofS.pseudintermediusisolates were methicillin-resistant. Half of the MRSP isolates were isolated from surgical site infections. Among the ten sequence types (ST) identified, nine were novel. ST71 was the most prevalent and associated with resistance to fluoroquinolones. Prior antimicrobial therapy, hospitalization, and surgical site infections seemed to be risk factors for MRSP acquisition. The present study showed a high rate of MDR staphylococci in infected dogs. MRSP was isolated from different clinical conditions, mainly surgical site infections. Additionally, this is the first study to extensively investigate the population structure of MRSP in Brazil, which revealed the dispersion of CC71 and nine novel ST. These findings raise concerns for both animal and human health due to the zoonotic potential of this species and limited therapeutic options available for MRSP infections.


  • Open Access

    Fecal Shedding of Multidrug Resistant Escherichia coli Isolates in Dogs Fed with Raw Meat-Based Diets in Brazil

    by Carolina Pantuzza Ramos, Carolina Yumi Iceri Kamei, Flávia Mello Viegas, Jonata de Melo Barbieri, João Luís Reis Cunha, Yaovi Mahuton Gildas Hounmanou, Fernanda Morcatti Coura, Jordana Almeida Santana, Francisco Carlos Faria Lobato, Anders Miki Bojesen, et al.

    The practice of feeding dogs raw meat-based diets (RMBDs) is growing in several countries, and the risks associated with the ingestion of pathogenic and antimicrobial-resistant Escherichia coli in dogs fed these diets are largely unknown. We characterized E. coli strains isolated from dogs fed either an RMBD or a conventional dry feed, according to the phylogroup, virulence genes, and antimicrobial susceptibility profiles of the bacteria. Two hundred and sixteen E. coli strains were isolated. Dogs fed RMBDs shed E. coli strains from the phylogroup E more frequently and were positive for the E. coli heat-stable enterotoxin 1-encoding gene. Isolates from RMBD-fed dogs were also frequently positive for multidrug-resistant E. coli isolates including extended-spectrum beta-lactamase (ESBL) producers. Whole-genome sequencing of seven ESBL-producing E. coli strains revealed that they predominantly harbored blaCTX-M-55, and two strains were also positive for the colistin-resistant gene mcr-1. These results suggest that feeding an RMBD can affect the dog’s microbiota, change the frequency of certain phylogroups, and increase the shedding of diarrheagenic E. coli. Also, feeding an RMBD seemed to be linked with the fecal shedding of multidrug-resistant E. coli, including the spread of strains harboring mobilizable colistin resistance and ESBL genes. This finding is of concern for both animal and human health.


  • Open Access

    Fecal shedding of Salmonella spp., Clostridium perfringens, and Clostridioides difficile in dogs fed raw meat-based diets in Brazil and their owners’ motivation

    by Flavia Mello Viegas, Carolina Pantuzza Ramos, Rafael Gariglio Clark Xavier, Emily Oliveira Lopes, Carlos Augusto Oliveira Júnior, Renata Marques Bagno, Amanda Nadia Diniz, Francisco Carlos Faria Lobato, Rodrigo Otávio Silveira Silva

    The present study aimed to explore the motivations of Brazilian dog owners and their knowledge about the risks related to raw meat-based diets (RMBD) as well as to evaluate important enteropathogens such as Salmonella spp., C. perfringens, and C. difficile, in feces of dogs fed different diets. The majority of the pet owners (69.3%) reported to have chosen this diet for their dogs, considering it to be more “natural”. A large number of owners declared that RMBD do not pose health risks for their animals (87.9%) or humans (98.8%), even though almost one third of the respondents (34.8%) declared having at least one individual at high risk of infection in contact with RMBD-fed dogs. Stool samples from 46 RMBD-fed dogs and 192 dogs fed commercial dry feed were collected. The present study revealed that dogs fed raw meat diets were almost 30 times more likely to be positive for Salmonella spp. than dogs on a conventional diet. Some of the serovars detected were commonly associated with human salmonellosis, such as S. Typhimurium and S. Saintpaul, and were multidrug resistant. RMBD-fed dogs were more likely to be positive for C. perfringens type A (p = 0.008) and one C. perfringens type F was isolated from these animals. Two toxigenic strains (4.3%) of C. difficile were isolated only from raw meat-fed dogs, all of which were under antibiotic therapy. These toxigenic C. difficile isolates were classified as RT106/ST54 and RT600/ST149, previously associated with infection in dogs and humans. The present work revealed that the owners have a tendency to ignore or are unaware of the risks associated with raw meat diets for dogs. Also, the higher fecal shedding of important enteropathogens in dogs fed RMBD suggests that this diet poses a risk for the animals and the people in contact with them.


  • Radiographic study of the development of the pelvis and hip and the femorotibial joints in domestic cats

    by Fernanda G Miranda, Izabela P Souza, Flávia M Viegas, Tábata T Megda, Anelise C Nepomuceno, Renato Cs Tôrres, Cleuza Mf Rezende

    Objectives: The aims of the present study were to monitor, by radiographic examination, the skeletal development of the pelvis and the femorotibial joints of the domestic cat from the first week of life until the closing of the growth plates. Methods: Radiographic examinations were collected from 15 domestic cats at weekly intervals during the first month and every 2 weeks from the second to the fourth month of age. After that, examinations were performed monthly until the age of 18 months. Results: The ischiopubic growth plate closed at 2 months of age, followed by the fusion of the iliopubic, ilioischial, proximal femoral, greater trochanter and proximal fibular growth plates. The distal femur and proximal tibial growth plates were the last to close, with fusion occurring at 18 months. The mean time to closure of the iliopubic, ilioischial and distal femoral growth plates was shorter in females. The ossification centers first appeared, in ascending order, beginning with the lesser trochanter, followed by the greater trochanter, proximal fibular epiphysis, tibial tuberosity, patella, ischial tuberosity and lateral sesamoid of the popliteus muscle. Conclusions and relevance: The complete closure of the growth plates of domestic cats occurs at approximately 18 months of age. Skeletal maturation at approximately 18 months of age is an important parameter to be considered in radiographic evaluation of certain skeletal changes, evolution of fractures and nutritional imbalance.


  • Open Access

    Antimicrobial susceptibility and molecular characterization of Salmonella serovar Ndolo isolated from outbreaks in cattle and horses

    by Carolina Pantuzza Ramos, Rafael Gariglio Clark Xavier, Carlos Augusto Gomes Leal, Elias Jorge Facury Filho, Antonio Ultimo de Carvalho, Flávia Mello Viegas, Isadora Honorato Pires, Emily Oliveira Lopes, Francisco Carlos Faria Lobato, Rodrigo Otávio Silveira Silva

    The present study aimed to describe and characterize, for the first time, two outbreaks of salmonellosis caused by Salmonella Ndolo in foals and calves in Brazil and compare the isolated strains with S. Ndolo previously identified in asymptomatic reptiles. The affected calves and foals presented fever, lethargy, and profuse diarrhea. Isolated strains were subjected to antimicrobial susceptibility testing, characterized according to virulence genes, and fingerprinted by ERIC-PCR. Salmonella Ndolo was identified in fecal samples from two foals and four calves. One isolate from a calf was resistant to amoxicillin/clavulanic acid, trimethoprim/sulfamethoxazole, and florfenicol. Strains from two other calves were resistant to oxytetracycline. All virulence genes tested were present in the isolates, and two major clusters of closely related strains were identified by ERIC-PCR, each per outbreak. This is the first report of Salmonella Ndolo infection in domestic and symptomatic animals. Previously, this serovar had been identified only in human infections. The presence of relevant virulence genes in all Salmonella Ndolo isolates and the detection of antimicrobial multi-resistant strains highlighted the importance of monitoring serovars associated with salmonellosis in domestic animals.