Figure 1.
Flowchart of development of the SEIARW model (1).
Table 1.
Variables within the SEIARW model (1).
Figure 2.
Infectious period of a typical shigellosis case with or without medical intervention.
m+n: Infectious period with no medical intervention; m+ηn: infectious period with partial medical intervention, which is equivalent to part of the infectious period with no medical intervention (m) and part of the infectious period with medical intervention (ηn); η(m+n): infectious period with a medical intervention that had been implemented on the date of illness onset.
Table 2.
Parameter definitions and values.
Table 3.
Results of simulation of effectiveness of shigellosis interventions implemented on October 19.
Figure 3.
Temporal distribution of shigellosis new cases in a primary school since October 5.
Figure 4.
Infectious periods of all cases.
A, Distribution of cases provided with fractional medical intervention (m+ηn) during infectious period; B, distribution of cases provided with combined intervention (η[m+n]) during infectious period; C, distribution of part of the infectious period with no medical intervention (m).
Figure 5.
Curve fitting of data from the baseline of the outbreak simulation from October 11 to 29.
Since the local CDC investigated and implemented the actual combined strategies at day 8 in this outbreak, SEIARW model with no intervention was employed for curve fitting during 0∼8 days (pink line), and SEIARW model with combined strategies of S1wIAPW was employed for curve fitting for the days thereafter (green line). Prevalence = I/N = i, where I is the infectious and N is the total number of persons.
Figure 6.
Results of simulation of efficacy of main intervention strategy options for controlling shigellosis outbreak.
Prevalence = I/N = i, where I is the infectious and N is the total number of persons.
Figure 7.
Sensitivity analysis to p based on the 1000 runs of the SEIARW model where p ranges from 0.0037 to 0.27.
Figure 8.
Sensitivity analysis to γ' based on the 1000 runs of the SEIARW model where γ' ranges from 0.0036 to 0.0357.