10.5061/DRYAD.J15NS
Buhnerkempe, Michael G.
National Institutes of Health
Prager, Katherine C.
National Institutes of Health
Strelioff, Christopher C.
University of California Los Angeles
Greig, Denise J.
National Oceanic and Atmospheric Administration
Laake, Jeff L.
Alaska Fisheries Science Center
Melin, Sharon R.
Alaska Fisheries Science Center
DeLong, Robert L.
Alaska Fisheries Science Center
Gulland, Frances M. D.
University of California Los Angeles
Lloyd-Smith, James O.
National Institutes of Health
Data from: Detecting signals of chronic shedding to explain pathogen
persistence: Leptospira interrogans in California sea lions
Dryad
dataset
2018
asymptomatic infection
marine mammal stranding
Zalophus californianus
subclinical shedding
maintenance host
Critical community size
birth pulse
epidemic drivers
Leptospira interrogans
partially-observed Markov process
seasonal transmission
pathogen reservoir
National Science Foundation
https://ror.org/021nxhr62
OCE-1335657
2018-02-07T00:00:00Z
2018-02-07T00:00:00Z
en
https://doi.org/10.1111/1365-2656.12656
5733 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Identifying mechanisms driving pathogen persistence is a vital component
of wildlife disease ecology and control. Asymptomatic, chronically
infected individuals are an oft-cited potential reservoir of infection but
demonstrations of the importance of chronic shedding to pathogen
persistence at the population level remain scarce. Studying chronic
shedding using commonly collected disease data is hampered by numerous
challenges, including short-term surveillance that focuses on single
epidemics and acutely ill individuals, the subtle dynamical influence of
chronic shedding relative to more obvious epidemic drivers, and poor
ability to differentiate between the effects of population prevalence of
chronic shedding versus intensity and duration of chronic shedding in
individuals. We use chronic shedding of Leptospira interrogans serovar
Pomona in California sea lions (Zalophus californianus) as a case study to
illustrate how these challenges can be addressed. Using
leptospirosis-induced strands as a measure of disease incidence, we fit
models with and without chronic shedding, and with different seasonal
drivers, to determine the timescale over which chronic shedding is
detectable and the interactions between chronic shedding and seasonal
drivers needed to explain persistence and outbreak patterns. Chronic
shedding can enable persistence of L. interrogans within the sea lion
population. However, the importance of chronic shedding was only apparent
when surveillance data included at least two outbreaks and the intervening
inter-epidemic trough during which fadeout of transmission was most
likely. Seasonal transmission, as opposed to seasonal recruitment of
susceptibles, was the dominant driver of seasonality in this system, and
both seasonal factors had limited impact on long-term pathogen
persistence. We show that the temporal extent of surveillance data can
have a dramatic impact on inferences about population processes, where the
failure to identify both short- and long-term ecological drivers can have
cascading impacts on understanding higher-order ecological phenomena, such
as pathogen persistence.
Weekly numbers of California sea lions stranding due to
leptospirosisIncluded are the number of California sea lions stranding due
to leptospirosis (LeptoStrands) in each week (Week) for four 2.5 year
(Year) eras. The four eras are 1984-1986, 1988-1990, 1991-1993, and
2004-2006, with each beginning in the 24th week to reflect a June 17 start
date.CSL_WeeklyLeptoStrandings_Buhnerkempe_etal.txt
California