Epidemiological analysis and modeling of aquatic pathogens

PARR-FHTT-2016-P-02

Description

One of the big questions concerning disease processes of aquatic pathogens is what factors influence pathogen prevalence in wild and cultured fish populations. The prevalence and intensity of pathogens can vary annually within and between fish stocks yet the drivers behind such annual fluctuations remain unresolved. Some fish populations can be free of virus one year yet be greater than 80% positive in subsequent years. The occurrence of such dramatic ‘on and off periods’ begs the questions “Why now?” and “Why was there an absence of virus in previous years?”

To better understand variations in aquatic pathogen prevalence in wild and farmed populations, this project will use epidemiological analytical approaches to study the patterns of aquatic pathogens in wild and cultured fish populations with the goal of identifying the factors that influence the occurrence of pathogens and disease.

To help understand the main drivers of pathogen epidemiology in aquatic systems, this project will:

1. Gather and assemble a comprehensive dataset of fish health analyses and salmon population metrics across multiple river systems.
2. Examine and compare annual pathogen prevalence among wild sockeye populations from multiple river systems.
3. Explore host, pathogen and environmental factors for potential correlates with pathogen variability in wild sockeye populations.

To achieve these objectives, we will compile fish health data sets with salmon population data from corresponding river systems, and using a mixed-method analysis and ecosystem health approach, determine how changes in pathogen prevalence in wild sockeye populations relate to environmental and other potentially important variables in an effort to understand how they may have “biased” fish health or pathogen prevalence. This process will help us construct a data-based logical argument that enables us to answer questions about how much specific environmental or other variables may have affected the health or pathogen status of year cohorts, taking other important system-level variables into account.

Findings

N/A

Publications

N/A

Program Name

Program for Aquaculture Regulatory Research (PARR)

Year(s)

2016 to 2018

Principal Investigator

Kyle Garver
Research Scientist, Pacific Biological Station
Email: Kyle.Garver@dfo-mpo.gc.ca