TY - JOUR
T1 - Modelling the transmission dynamics of acute haemorrhagic conjuctivitis
T2 - Application to the 2003 outbreak in Mexico
AU - Chowell, G.
AU - Shim, E.
AU - Brauer, Fred
AU - Diaz-Dueñas, P.
AU - Hyman, J. M.
AU - Castillo-Chavez, Carlos
PY - 2006/6/15
Y1 - 2006/6/15
N2 - We model an outbreak of acute haemorrhagic conjunctivitis (AHC) using a simple epidemic model that includes susceptible, infectious, reported, and recovered classes. The model's framework considers the impact of underreporting and behaviour changes on the transmission rate and is applied to a recent epidemic of AHC in Mexico, using a fit to the cumulative number of cases to estimate model parameters, which agree with those derived from clinical studies. The model predicts a 'mean time from symptomatic onset to diagnosis' of 1.43 days (95 per cent CI: 1-2.5) and that the final size of the Mexican epidemic was underreported by 39 per cent. We estimate that a primary infectious case generates approximately 3 secondary cases (R0* = 2.64, SD 0.65). We explore the impact of interventions on the final epidemic size, and estimate a 36 per cent reduction in the transmission rate due to behaviour changes. The effectiveness of the behaviour changes in slowing the epidemic is evident at 21.90 (SD 0.19) days after the first reported case. Results therefore support current public health policy including expeditious announcement of the outbreak and public health information press releases that instruct individuals on avoiding contagion and encourage them to seek diagnosis in hospital clinics.
AB - We model an outbreak of acute haemorrhagic conjunctivitis (AHC) using a simple epidemic model that includes susceptible, infectious, reported, and recovered classes. The model's framework considers the impact of underreporting and behaviour changes on the transmission rate and is applied to a recent epidemic of AHC in Mexico, using a fit to the cumulative number of cases to estimate model parameters, which agree with those derived from clinical studies. The model predicts a 'mean time from symptomatic onset to diagnosis' of 1.43 days (95 per cent CI: 1-2.5) and that the final size of the Mexican epidemic was underreported by 39 per cent. We estimate that a primary infectious case generates approximately 3 secondary cases (R0* = 2.64, SD 0.65). We explore the impact of interventions on the final epidemic size, and estimate a 36 per cent reduction in the transmission rate due to behaviour changes. The effectiveness of the behaviour changes in slowing the epidemic is evident at 21.90 (SD 0.19) days after the first reported case. Results therefore support current public health policy including expeditious announcement of the outbreak and public health information press releases that instruct individuals on avoiding contagion and encourage them to seek diagnosis in hospital clinics.
KW - Acute haemorrhagic conjuctivitis
KW - Epidemic model
KW - Parameter estimation
KW - Parameter identifiability
KW - Reproductive number
KW - Underreporting
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U2 - 10.1002/sim.2352
DO - 10.1002/sim.2352
M3 - Article
C2 - 16158395
AN - SCOPUS:33744792626
SN - 0277-6715
VL - 25
SP - 1840
EP - 1857
JO - Statistics in Medicine
JF - Statistics in Medicine
IS - 11
ER -