Browsing by Author "Culhane, Marie"

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    Analysis of geographic location and pathways for influenza A virus infection of commercial upland game bird and conventional poultry farms in the United States of America
    (BMC veterinary research, 2019) Ssematimba, Amos; Charles, Kaitlyn M. St.; Bonney, Peter J.; Malladi, Sasidhar; Culhane, Marie; Goldsmith, Timothy J.; Halvorson, David A.; Cardona, Carol J.
    Avian influenza (AI) is an infectious viral disease that affects several species and has zoonotic potential. Due to its associated health and economic repercussions, minimizing AI outbreaks is important. However, most control measures are generic and mostly target pathways important for the conventional poultry farms producing chickens, turkeys, and eggs and may not target other pathways that may be specific to the upland game bird sector. The goal of this study is to provide evidence to support the development of novel strategies for sector-specific AI control by comparing and contrasting practices and potential pathways for spread in upland game bird farms with those for conventional poultry farms in the United States. Farm practices and processes, seasonality of activities, geographic location and inter-farm distance were analyzed across the sectors. All the identified differences were framed and discussed in the context of their associated pathways for virus introduction into the farm and subsequent between-farm spread. Results: Differences stemming from production systems and seasonality, inter-farm distance and farm densities were evident and these could influence both fomite-mediated and local-area spread risks. Upland game bird farms operate under a single, independent owner rather than being contracted with or owned by a company with other farms as is the case with conventional poultry. The seasonal marketing of upland game birds, largely driven by hunting seasons, implies that movements are seasonal and customer-vendor dynamics vary between industry groups. Farm location analysis revealed that, on average, an upland game bird premises was 15.42 km away from the nearest neighboring premises with birds compared to 3.74 km for turkey premises. Compared to turkey premises, the average poultry farm density in a radius of 10 km of an upland game bird premises was less than a half, and turkey premises were 3.8 times (43.5% compared with 11.5%) more likely to fall within a control area during the 2015 Minnesota outbreak. Conclusions: We conclude that the existing differences in the seasonality of production, isolated geographic location and epidemiological seclusion of farms influence AI spread dynamics and therefore disease control measures should be informed by these and other factors to achieve success.
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    An Assessment of the Risk Associated with the Movement Broilers to Market Into, Within, and Out of a Control Area During a Highly Pathogenic Avian Influenza Outbreak in the United States
    (University of Minnesota Center for Secure Food Systems, 2018) Cardona, Carol; Alexander, Carie; Bonney, Peter; Contadini, Francesca; Culhane, Marie; Goldsmith, Timothy; Halvorson, David; Linskens, Eric; Malladi, Sasidhar; Ssematimba, Amos; Umber, Jamie; Weaver, Todd; Walz, Emily
    In the event of a highly pathogenic avian influenza (HPAI) outbreak in the United States, poultry industry, local, State, and Federal authorities will implement a foreign animal disease emergency response. In these circumstances, permit requests to move poultry and poultry products must be supported by risk assessments which demonstrate that the risk of HPAI spread associated with the movement is acceptable. Performing the risk assessments prior to an HPAI outbreak can enhance emergency response and facilitate timely movement permitting decisions during an outbreak. This document assesses the risk that the movement of market-age broilers to processing (i.e., broilers to market), during an HPAI outbreak, from a premises located within the Control Area, will result in HPAI virus spread to a virus-free poultry premises. This risk assessment is a joint effort of the Secure Broiler Supply (SBS) Working Group, which is made up of representatives from the broiler industry, academia, State Animal Health Officials (SAHOs), and the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA:APHIS), to support permits for the terminal movement of broilers to processing during an HPAI outbreak. This assessment is applicable to intensively raised commercial or contract grow-out broiler premises that do not have other poultry on the premises and practice an all-in, all-out single-age growing system. These broiler facilities must participate in the USDA APHIS National Poultry Improvement Plan (NPIP) and follow the SBS Plan in the event of an HPAI outbreak. The SBS Plan contains science-based outbreak measures developed by the SBS working group to mitigate the risk of HPAI spread associated with the terminal movement of live birds to market.
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    An Assessment of the Risk Associated with the Movement Turkeys to Market Into, Within, and Out of a Control Area During a Highly Pathogenic Avian Influenza Outbreak in the United States
    (University of Minnesota Center for Secure Food Systems, 2018) Cardona, Carol; Alexander, Carie; Bergeron, Justin; Bonney, Peter; Culhane, Marie; Goldsmith, Timothy; Halvorson, David; Linskens, Eric; Malladi, Sasidhar; Ssematimba, Amos; Walz, Emily; Weaver, Todd; Umber, Jamie
    In the event of a highly pathogenic avian influenza (HPAI) outbreak in the United States, poultry industry, local, state, and federal authorities will implement a foreign animal disease emergency response. In these circumstances, permit requests to move poultry and poultry products must be supported by risk assessments which demonstrate that the risk of HPAI spread associated with the movement is acceptable. Performing the risk assessments prior to an HPAI outbreak can enhance emergency response and facilitate timely movement permitting decisions during an outbreak. This document assesses the risk that the movement of market-age turkeys to processing (i.e., turkeys to market), during an HPAI outbreak, from a premises located within the Control Area, will result in HPAI virus spread to a virus-free commercial poultry population (e.g., another poultry farm or birds remaining on a multi-age premises). The purpose of this assessment is to provide regulators with an objective and defensible method of assessing the disease risk associated with the movement of live turkeys (for meat) to slaughter.
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    Avian Influenza in the U.S. Commercial Upland Game Bird Industry: An Analysis of Selected Practices as Potential Exposure Pathways and Surveillance System Data Reporting
    (Avian diseases, 2018) Charles, Kaitlyn M. St.; Ssematimba, Amos; Malladi, Sasidhar; Bonney, Peter J.; Linskens, Eric; Culhane, Marie; Goldsmith, Timothy J.; Halvorson, David A.; Cardona, Carol J.
    Producing a smaller yield of higher-value birds compared to conventional poultry production, the U.S. commercial upland game bird industry deals primarily in the sale of live birds for recreational hunting. In this study, our aims were to gain insights into the occurrence of avian influenza (AI) in the U.S. commercial upland game bird industry in comparison to other poultry sectors, to identify the presence of the specific AI risk factors in the practices of raising ducks on site and having connections to live bird markets (LBMs), and to assess how AI surveillance systems may have played a role in the reporting of the presence of exposure pathway–related information. We found that 23 AI epizootics involving upland game bird premises were reported, compared to 485 epizootics in the other poultry industries, and 86% of epizootics involving upland game birds were limited to only one premises. Regarding specific AI risk factors, 70% of upland game bird epizootics involved one of the two examined practices. In assessing the impact of surveillance systems, data framed around the implementation of surveillance systems revealed that the introduction of active surveillance coincided with the more thorough reporting of both the raising of ducks on site and premises having connections to LBMs. Our results suggest the need for more thorough data collection during epizootics and the need to assess additional exposure pathways specific to the commercial raise-for-release upland game bird industry.
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    Estimating epidemiological parameters using diagnostic testing data from low pathogenicity avian influenza infected turkey houses
    (Scientific reports, 2021) Bonney, Peter J.; Malladi, Sasidhar; Ssematimba, Amos; Spackman, Erica; Torchetti, Mia Kim; Culhane, Marie; Cardona, Carol J.
    Limiting spread of low pathogenicity avian influenza (LPAI) during an outbreak is critical to reduce the negative impact on poultry producers and local economies. Mathematical models of disease transmission can support outbreak control efforts by estimating relevant epidemiological parameters. In this article, diagnostic testing data from each house on a premises infected during a LPAI H5N2 outbreak in the state of Minnesota in the United States in 2018 was used to estimate the time of virus introduction and adequate contact rate, which determines the rate of disease spread. A well-defined most likely time of virus introduction, and upper and lower 95% credibility intervals were estimated for each house. The length of the 95% credibility intervals ranged from 11 to 22 with a mean of 17 days. In some houses the contact rate estimates were also well-defined; however, the estimated upper 95% credibility interval bound for the contact rate was occasionally dependent on the upper bound of the prior distribution. The estimated modes ranged from 0.5 to 6.0 with a mean of 2.8 contacts per day. These estimates can be improved with early detection, increased testing of monitored premises, and combining the results of multiple barns that possess similar production systems.