Hatem Kittana

Dr. Hatem Kittana


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
8 February 2025 in Pathogens
Verified
Journal Article
Open access
PDF file
EDEthan Dudley
Ethan Dudley
MSMatthew Scott
Matthew Scott
Hatem KittanaHatem Kittana
Hatem Kittana
ATAlexis C. Thompson
Alexis C. Thompson
RVRobert Valeris-Chacin
Robert Valeris-Chacin
Bovine respiratory disease (BRD) is a major economic and animal welfare issue in the beef industry. Mycoplasma bovis is one of the main causal organisms, particularly in chronic cases. Due to the difficulty of isolating M. bovis from clinical isolates, there is a lack of information on the genetic diversity of this pathogen in the Texas panhandle region of the United States. Therefore, our objective was to provide genome-level characterization of M. bovis isolated from the lung lesions of beef and dairy cattle in the Texas panhandle. Fifty-four isolates displaying mycoplasma-like growth were recovered from bovine lung lesions by the Texas Veterinary Medical Diagnostic Laboratory in 2021 and 2022. Of these isolates, 32 were determined to be M. bovis via species-specific qPCR using the uvrC gene. Long-read whole-genome sequencing was used to identify key virulence factors, antimicrobial resistance genes, and to assess the genetic diversity of these isolates. Fisher’s exact tests were used to identify associations between isolate characteristics and host metadata, including the state of origin, type of operation, animal age, and animal sex. Our results indicate that there is considerable genetic diversity among the M. bovis isolates, despite their shared geography in the Texas panhandle, though significant clustering based on host metadata was observed. Analysis of the pangenome showed that the M. bovis isolates in this study also harbor a diverse array of virulence genes, but no antimicrobial resistance genes were identified in this study.

4 September 2024 in Antibiotics
Verified
Journal Article
Open access
PDF file
MCMax Chung
Max Chung
EDEthan Dudley
Ethan Dudley
Hatem KittanaHatem Kittana
Hatem Kittana
ATAlexis C. Thompson
Alexis C. Thompson
MSMatthew Scott
Matthew Scott
RVRobert Valeris-Chacin
Robert Valeris-Chacin
Rising antimicrobial resistance (AMR) in Salmonella serotypes host-adapted to cattle is of increasing concern to the beef and dairy industry. The bulk of the existing literature focuses on AMR post-slaughter. In comparison, the understanding of AMR in Salmonella among pre-harvest cattle is still limited, particularly in Texas, which ranks top five in beef and dairy exports in the United States; inherently, the health of Texas cattle has nationwide implications for the health of the United States beef and dairy industry. In this study, long-read whole genome sequencing and bioinformatic methods were utilized to analyze antimicrobial resistance genes (ARGs) in 98 isolates from beef and dairy cattle in the Texas Panhandle. Fisher exact tests and elastic net models accounting for population structure were used to infer associations between genomic ARG profiles and antimicrobial phenotypic profiles and metadata. Gene mapping was also performed to assess the role of mobile genetic elements in harboring ARGs. Antimicrobial resistance genes were found to be statistically different between the type of cattle operation and Salmonella serotypes. Beef operations were statistically significantly associated with more ARGs compared to dairy operations. Salmonella Heidelberg, followed by Salmonella Dublin isolates, were associated with the most ARGs. Additionally, specific classes of ARGs were only present within mobile genetic elements.

1 November 2025 in Pathogens
Verified
Journal Article
Open access
PDF file
XZXirui Zhang
Xirui Zhang
DLDanqin Li
Danqin Li
MAMichael D Apley
Michael D Apley
LKLocke Anderson Karriker
Locke Anderson Karriker
JCJoseph F Connor
Joseph F Connor
JSJishu Shi
Jishu Shi
Antimicrobial resistance (AMR) is a significant global health concern, and the use of antibiotics in livestock, including swine production, is a major contributor. Vaccines offer a promising alternative for controlling bacterial infections in pigs, but their widespread use is often hindered by biological, economic, and practical challenges. This study surveyed U.S. swine veterinarians to identify which bacterial diseases require better vaccines and to understand the barriers to their adoption. Nineteen veterinarians with an average of 24.7 years of experience were surveyed across 21 states. The results identified Streptococcus suis, Escherichia coli, Mycoplasma hyopneumoniae, and Glaesserella parasuis as the most critical pathogens needing improved vaccines. Veterinarians anticipated significant improvements in vaccine efficacy for S. suis and E. coli during the nursery stage and expressed a willingness to pay 1.8 and 1.9 times their current prices, respectively. While expectations for M. hyo vaccine improvements were not significant, veterinarians expressed the highest willingness to pay (4.2 times the current price), citing the potential for disease eradication. This research highlights that developing effective vaccines for S. suis and E. coli should be the most urgent priority due to their significant economic impact and rising AMR concerns. However, M. hyo vaccine development holds the most economic potential due to the possibility of eradication. Our research provides a roadmap for future efforts to combat AMR in the swine industry, emphasizing key economic, policy, and educational considerations for successful vaccine implementation.

17 July 2024 in Preprints.org
Verified
Preprint
Open access
PDF file
MCMax Chung
Max Chung
EDEthan Dudley
Ethan Dudley
Hatem KittanaHatem Kittana
Hatem Kittana
ATAlexis C. Thompson
Alexis C. Thompson
MSMatthew Scott
Matthew Scott
RVRobert Valeris-Chacin
Robert Valeris-Chacin
Rising antimicrobial resistance (AMR) in Salmonella serotypes host-adapted to cattle is of increasing concern to the beef and dairy industry. The bulk of the existing literature focuses on AMR post-slaughter. In comparison, the understanding of AMR in Salmonella among pre-harvest cattle is still limited, particularly in Texas, which ranks top five in beef and dairy exports in the United States; inherently, the health of Texas cattle has nationwide implications for the health of the United States beef and dairy industry. In this study, long-read whole genome sequencing and bioinformatic methods were utilized to analyze antimicrobial resistance genes (ARGs) in 98 isolates from beef and dairy cattle in the Texas Panhandle. Fisher exact tests and elastic net models accounting for population structure were used to infer associations between ARGs and antimicrobial phenotypic profiles and metadata. Gene mapping was also performed to assess the role of mobile genetic elements in harboring ARGs. ARG were found to be statistically different between the type of cattle operation and Salmonella serotypes. Beef operations were statistically significantly associated with more resistance genes compared to dairy operations. Salmonella Heidelberg, followed by Salmonella Dublin isolates, were associated with the most ARGs. Additionally, specific classes of ARGs were only present within mobile genetic elements.

9 December 2025 in Pathogens
Verified
Journal Article
Open access
PDF file
DLDanqin Li
Danqin Li
XZXirui Zhang
Xirui Zhang
MAMichael D Apley
Michael D Apley
JGJordan T. Gebhardt
Jordan T. Gebhardt
LKLocke Anderson Karriker
Locke Anderson Karriker
JSJishu Shi
Jishu Shi
Antimicrobial resistance (AMR) is an increasing concern in food animal production. In swine herds, viral infections often lead to secondary bacterial disease and higher antimicrobial use (AMU). This study describes how U.S. swine veterinarians view the role of viral vaccines in reducing this reliance on antimicrobials. We conducted a national survey of swine practitioners and follow-up semi-structured interviews with a subset of respondents. Across participants, porcine reproductive and respiratory syndrome (PRRS), swine influenza (SIV), and rotaviral enteritis were most often named as viral diseases in urgent need of improved vaccines. These diseases cause substantial economic losses and frequently trigger AMU in commercial herds. Veterinarians reported several recurring challenges with current vaccines, including limited cross-protection against field strains, interference from maternally derived antibodies, and short duration of protection. Despite these limitations, most respondents supported vaccination as a key tool to curb AMU and indicated they would accept higher prices for clearly improved products. These findings reveal both a clear need and specific opportunities for future vaccine development to provide broader and more reliable protection, reduce AMU, and help slow the development of AMR.

6 October 2025 in Preprints.org
Verified
Preprint
Open access
PDF file
XZXirui Zhang
Xirui Zhang
DLDanqin Li
Danqin Li
MAMichael D Apley
Michael D Apley
LKLocke Anderson Karriker
Locke Anderson Karriker
JCJoseph F Connor
Joseph F Connor
JSJishu Shi
Jishu Shi
Antimicrobial resistance (AMR) is a significant global health concern, and the use of antibiotics in livestock, including swine production, is a major contributor. Vaccines offer a promising alternative for controlling bacterial infections in pigs, but their widespread use is often hindered by biological, economic, and practical challenges. This study surveyed U.S. swine veterinarians to identify which bacterial diseases re-quire better vaccines and to understand the barriers to their adoption. Nineteen vet-erinarians with an average of 24.7 years of experience were surveyed across 21 states. The results identified Streptococcus suis, Escherichia coli, Mycoplasma hyopneumoniae, and Glaesserella parasuis as the most critical pathogens needing improved vaccines. Veter-inarians anticipated significant improvements in vaccine efficacy for S. suis and E. coli during the nursery stage and expressed a willingness to pay 1.8 and 1.9 times their current prices, respectively. While expectations for M. hyo vaccine improvements were not significant, veterinarians expressed the highest willingness to pay (4.2 times the current price), citing the potential for disease eradication. This research highlights that developing effective vaccines for S. suis and E. coli should be the most urgent priority due to their significant economic impact and rising AMR concerns. However, M. hyo vaccine development holds the most economic potential due to the possibility of erad-ication. Our research provides a roadmap for future efforts to combat AMR in the swine industry, emphasizing key economic, policy, and educational considerations for successful vaccine implementation.