Antimicrobial Resistance in Fecal Escherichia coli and Salmonella enterica from Dairy Calves: A Systematic Review.

The discovery of antibiotics brought with it many advances in the health and well-being of humans and animals; however, in recent years development of antimicrobial resistance (AMR) has increasingly become a concern. Much of the antibiotic use on dairy farms is for disease management in mature cattle, and AMR in fecal organisms is relatively rare in this group. However, young dairy calves often carry high levels of AMR in their fecal Escherichia coli and Salmonella enterica, which could provide a potential reservoir of AMR genes on dairy farms. To develop practical and effective antibiotic stewardship policies for dairy calf rearing, it is vital to have a solid understanding of the current state of knowledge regarding AMR in these animals. A systematic review process was used to summarize the current scientific literature regarding AMR in fecal S. enterica and E. coli and associations between management practices and AMR prevalence in dairy calves in the United States and Canada. Seven online databases were searched for literature published from 1997 to 2018. Multiple studies indicated an association between preweaned calves and increased risk of fecal shedding of resistant bacteria, compared to other animal groups on dairy farms. There also was evidence, although less consistent, of an impact of antibiotic treatment, antibiotic-containing milk replacer feeding, and feeding nonsalable or waste milk (WM) on the presence of AMR bacteria. Overall, the research summarized in this systematic review highlights the need for continued research on the impact of management practices, including antibiotic use, WM feeding, and disease prevention practices in reducing AMR in E. coli and S. enterica in dairy calves. In addition, few data were available on physiological and microbiological factors that may contribute to the high relative populations of resistant bacteria in young calves, suggesting another valuable area of future research.

Composition and duties of local boards of health: findings from a 2011 national survey.

OBJECTIVE: To describe the composition and duties of local boards of health (LBOHs). DESIGN: An online and written survey was utilized for data collection. The survey included demographics, roles and responsibilities, orientation and training, and concerns and needs of LBOHs. SETTING: This article seeks to expand what limited information we have on the composition and duties of LBOHs as an important foundational step in analyzing the role of LBOHs in leveraging improved public health outcomes. PARTICIPANTS: In 2011, the mixed methods survey was sent to a random sample of 2420 LBOHs in the 41 states, which meet the definition of having LBOHs. MAIN OUTCOME MEASURE: The data represent responses from 353 LBOHs in 35 states. RESULTS: Elected officials appoint members of 68% of LBOHs. The average board consists of a 7-member, county-based LBOH made up primarily of males (60%) and whites (96%). Hispanics make up 9% of boards. The majority of LBOH chairs have a graduate degree but no formal education or experience in public health. Local boards of health report reviewing public health regulations as their most common power but list recommending the approval of the budget for the local health department as boards' most frequent activity in the past 3 years. CONCLUSIONS: LBOH members and chairs are more similar in demographics to the top executives at local health departments than the general population or the public health workforce. Most LBOH chairs, however, lack experience in public health, and a quarter or more of LBOHs do not use their powers to set or recommend health priorities as a mechanism to leverage better community health outcomes.

The status of state boards of health in 2010.

OBJECTIVE: The objective of the survey was to update information about state boards of health throughout the United States and, based on the results of the survey, to determine how the National Association of Local Boards of Health can serve as a resource to assist state boards in fulfilling their responsibilities and duties. DESIGN: A written survey was developed to collect information about the composition, organizational structure, statutory authority, roles, responsibilities, concerns, and needs of state boards of health. SETTING: Information specific to state boards of health has not been collected on a routine basis by any organization, therefore the National Association of Local Boards of Health sought to compile current information on these boards that will be maintained and updated on a routine basis. PARTICIPANTS: Surveys were mailed to 31 contacts for state boards of health. MAIN OUTCOME MEASURE: After follow-up attempts, responses (n = 27) were received from all but four boards for a response rate of 87.1% with one indicating no board. RESULTS: Consumers and physicians were most frequently reported as required members of the boards. Board members were appointed solely by the governor in 21 (80.8%) states. Nine boards (34.6%) indicated an advisory only capacity regarding statutory authority while the others were governing, policy making, or had multiple authorities. Specific responsibilities of all of the boards included, regardless of statutory authority, advising the state chief health officer (84.6%), advising the governor (42.3%), and adopting and enforcing statutes (38.5%). CONCLUSIONS: State boards of health have undergone changes and likely will continue to evolve in their role in public health governance as demonstrated by this survey. This repository of current data on state boards of health could be of use to public health researchers, boards of health, and national public health organizations in strengthening public health governance.

Blinded, controlled field trial of two commercially available Mycoplasma bovis bacterin vaccines in veal calves.

Mycoplasma bovis is an etiologic agent of pneumonia, arthritis, and otitis in young calves, such as those found in the special-fed veal industry. We conducted a blinded, controlled trial of two commercially available M. bovis bacterin vaccines for the prevention of respiratory disease in calves associated with M. bovis infection. Calves were randomly assigned to a subcutaneous treatment of vaccine A (n=50), adjuvant A (n=50), vaccine B (n=50), or 0.9% sterile saline solution (n=50) beginning at 27 days of age. Upper-respiratory tract colonization was not impacted by vaccination status. Vaccine A significantly reduced the presence of lung lesions (p=0.0325), however there was no significant reduction of M. bovis in lung lesions. Vaccine B did not significantly reduce total lung lesions or M. bovis-specific lung lesions. The relative risk was determined to be 0.56, 1.0, and 1.36 for vaccine A, adjuvant A, and vaccine B, respectively. There was no association between the total specific antibody isotype (IgM, IgG1, IgG2, IgA) concentrations or M. bovis antibodies and the M. bovis-associated morbidity in the veal calves. Under the field conditions of this study, observed vaccine efficacy for vaccine A and vaccine B was 44% and less than 1%, respectively.

Occupational health characteristics of women on dairy farms in Pennsylvania.

Women play a significant role in Pennsylvania production agriculture, thereby exposing themselves to occupational health risks. The goal of this cross-sectional study was to assess the incidence of health conditions with a possible zoonotic origin in this underserved population. A written survey was sent to a stratified, random sample of dairy farms in Pennsylvania (n = 3709) using a modified version of the Dillman method. In addition to demographic data, the survey was used to collect information on the occurrence of zoonotic diseases, gastrointestinal illnesses, respiratory problems, dermatoses, and women's reproductive health issues. Of the 624 respondents, 10.4% (n = 65) reported that they had contracted a disease from an animal. Interestingly, only 9 respondents indicated that they had suffered from foodborne illnesses in the past year including salmonellosis (n = 1), campylobacteriosis (n = 1), and gastroenteritis due to Escherichia coli (n = 1). A risk factor associated with difficulty breathing was the lack of use of a breathing mask, whereas ventilation in the free stall area appeared to offer a protective effect. Difficulty breathing was reported by 9.8% (n = 61) of the respondents. Risk factors associated with skin disorders included raising fruits and/or vegetables, raising swine, and not wearing gloves when milking. The findings of the study suggest that many of the illnesses and conditions could have been acquired by working with dairy animals and their environment. Based on the findings of this study, additional investigations on the causes and prevention of these illnesses are warranted.

Occupational health behaviors and habits of women on dairy farms in Pennsylvania.

The goal of this study was to determine what tasks women perform, behaviors that could result in exposure to zoonotic disease, and preventative measures practiced by women on dairy farms. A written survey was sent to a stratified, random sample of dairy farms in Pennsylvania (n = 3709) using a modified version of the Dillman method. The tasks most commonly performed by the respondents (n = 624) included milking (70.8%), feeding (60.6%), and cleaning stalls (42.6%). The use of personal protective equipment was infrequent. Gloves were always worn when milking by 32.7%. More respondents, 96.5%, changed their clothes at least sometimes before working in the barn as compared to when leaving the barn. Handwashing was always performed by 86.7% after assisting with delivering calves, whereas 71.1% always washed their hands after milking. Eating and drinking in the barn were practiced by 45.0% and 72.0%, respectively. Veterinary obstetric drugs were administered by 28.2% of the respondents. Most of the respondents, 89.7%, indicated that they felt they had minimal to no risk of contracting a disease from the animals with which they worked.