TY - JOUR
T1 - A sharp threshold for disease persistence in host metapopulations
AU - Dhirasakdanon, Thanate
AU - Thieme, Horst R.
AU - Van Den Driessche, P.
N1 - Funding Information:
The authors thank two anonymous referees for helpful comments. This study was partially supported by NSF grant DMS 0314529 (T.D. and H.R.T.) and by NSERC and MITACS (P.v.d.D).
PY - 2007/10
Y1 - 2007/10
N2 - A sharp threshold is established that separates disease persistence from the extinction of small disease outbreaks in an S→E→I→R→S type metapopulation model. The travel rates between patches depend on disease prevalence. The threshold is formulated in terms of a basic replacement ratio (disease reproduction number), ℛ0, and, equivalently, in terms of the spectral bound of a transmission and travel matrix. Since frequency-dependent (standard) incidence is assumed, the threshold results do not require knowledge of a disease-free equilibrium. As a trade-off, for ℛ0>1, only uniform weak disease persistence is shown in general, while uniform strong persistence is proved for the special case of constant recruitment of susceptibles into the patch populations. For ℛ0<1, Lyapunov's direct stability method shows that small disease outbreaks do not spread much and eventually die out.
AB - A sharp threshold is established that separates disease persistence from the extinction of small disease outbreaks in an S→E→I→R→S type metapopulation model. The travel rates between patches depend on disease prevalence. The threshold is formulated in terms of a basic replacement ratio (disease reproduction number), ℛ0, and, equivalently, in terms of the spectral bound of a transmission and travel matrix. Since frequency-dependent (standard) incidence is assumed, the threshold results do not require knowledge of a disease-free equilibrium. As a trade-off, for ℛ0>1, only uniform weak disease persistence is shown in general, while uniform strong persistence is proved for the special case of constant recruitment of susceptibles into the patch populations. For ℛ0<1, Lyapunov's direct stability method shows that small disease outbreaks do not spread much and eventually die out.
KW - Basic reproduction number
KW - Extinction
KW - Persistence
UR - http://www.scopus.com/inward/record.url?scp=58149308728&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=58149308728&partnerID=8YFLogxK
U2 - 10.1080/17513750701605465
DO - 10.1080/17513750701605465
M3 - Article
C2 - 22876822
AN - SCOPUS:58149308728
SN - 1751-3758
VL - 1
SP - 363
EP - 378
JO - Journal of biological dynamics
JF - Journal of biological dynamics
IS - 4
ER -