Health Outcomes Arising from Human-Animal Interactions Including Zoonotic Disease and Antimicrobial Resistance

Date of Approval: 
2020-11-18 00:00:00
Lay Summary: 
The health of animals and people are interconnected and interdependent, a fact increasingly recognised by global organisations concerned with human health and animal health alike and one brought into sharp relief by the coronavirus pandemic. Sixty percent of infectious diseases that can affect people are zoonotic (transmissible between animals and humans), yet despite their combined prevalence, and statutory reporting, zoonotic diseases and their consequences are poorly characterised. Of additional concern is antimicrobial resistance (AMR); (whereby disease-causing micro-organisms become resistant to antibiotics) and its relationship to antibiotic use in food animals. Agricultural and animal health workers are directly at risk of colonization with drug-resistant bacteria through close contact with infected animals providing a conduit for the entry of resistance genes into community and hospital environments, where further spread into pathogens is possible. The proposed study has two principal objectives: 1) to address urgent gaps in understanding both the near- and longer-term impacts that zoonotic disease has on human health (including subsequent illness and death) and healthcare resource use; and 2) to explore the association between occupational exposure to food animals and antimicrobial treatment patterns, antibiotic treatment failure (ATF), and reported AMR.
Technical Summary: 
That animal and human health are interdependent is increasingly recognised. Sixty percent of infectious diseases in humans are zoonotic, but despite their combined prevalence and statutory reporting in the UK, zoonoses are poorly studied. Of additional concern is antimicrobial resistance (AMR) and its relationship to antibiotic use in food animals where agricultural and animal health workers are directly at risk of colonization with drug-resistant bacteria through close contact with infected animals. This study has two objectives: 1) to characterise the burden of human illness associated with a range of zoonotic diseases; and 2) to explore the association between occupational exposure to food animals and antimicrobial treatment patterns (ATP), antibiotic treatment failure (ATF), and reported AMR. Objective 1 has the following aims with respect to zoonotic diseases: 1) chart epidemiological trends (primary); 2) describe phenotypic susceptibility; 3) characterise acute and chronic co-morbid sequelae; 4) enumerate not only excess mortality but also 5) excess health resource use arising. Objective 2 will be met by comparing antimicrobial treatment patterns, ATF, and AMR between agricultural workers, co-habitants and matched controls. Matched cohorts will utilise the CPRD GOLD and Aurum datasets and linked HES, mortality, deprivation, and rurality data. To objective 1, primary exposure is a diagnosis of a notifiable zoonotic disease while principal outcomes are age-sex adjusted co-morbidity, all-cause mortality, and disaggregated health resource use. To objective 2, agricultural and animal health workers and co-habitants will be matched to non-agriculturally occupied controls where ATP is described by annual incidence per infection type; ATF by either 2nd-line antibiotic or clinical failure following first antibiotic for specified infection; with AMR determined from clinical codes and laboratory results. Event rates between cases and matched controls will be assessed by Poisson regression, ATF likelihood by conditional logistic regression, and healthcare cost differences by generalised linear modelling.
Health Outcomes to be Measured: 
Zoonoses incidence (disaggregated); Charlson Co-morbidity Index; all-cause mortality; healthcare resource use expressed as nor only rate but also cost for each of: GP consultation; other primary care consultations; hospital admissions; A&E attendance; outpatient referral; antibiotic usage; antibiotic treatment failure; antimicrobial resistance
Application Number: 
20_000086
Collaborators: 

Alex Cook - Chief Investigator - University of Surrey
Georgina Cherry - Corresponding Applicant - University of Surrey
Andrew Hancock - Collaborator - Zoetis Inc.
Chris D Poole - Collaborator - Digital Health Labs Limited
Georgina Cherry - Collaborator - University of Surrey
Isaac Odeyemi - Collaborator - Zoetis Inc.
James Frost - Collaborator - Digital Health Labs Limited

Linkages: 
2011 Rural-Urban Classification at LSOA level;HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Practice Level Index of Multiple Deprivation