aegypti mosquito, strongly suggests that the major factor driving the exponential increase of the
epidemic curve of arboviruses in naive populations is the transmission efficiency of the vector.
Caption: Figure 1:
Epidemic curves for age (a) and cohort (b) dimensions.
No differences in new infected cases at peak
epidemic curve or total infected cases were observed for different intervention activation times (Figures 11(a) and 11(b)).
A significant drop in the number of laboratory-confirmed cases during the latter half of the second wave is obvious in the
epidemic curve, and may have affected the strength of the measured association.
Epidemic curve began on May 18, 2007 and reached at peak on June 6, 2007 after that it declined.
Estimated cases prevented by a vaccination program (by population subgroup, at specific points in time, Phase 2+) = Doses administered (using the estimates from the 2 weeks prior to a specific date) x probability of not having had a prior clinical or subclinical infection (based on Interim
epidemic curve, Equation 1b) x probability of having a future clinical infection (based on Interim
epidemic curve, Equation 1b) x vaccine effectiveness
The
epidemic curve for Taiwan reveals the very rapid rise in cases resulting from the hospital outbreak.
The
epidemic curve peaked in the first week of May, which was 1 week after molecular diagnosis of ZIKV in 8 patients residing ~50 km from Salvador and during a period of intense media coverage of the outbreak (Figure) (6).
Thus, the effect of these changes on the shape of the
epidemic curve is small.
We assumed that the
epidemic curve of exanthematous illness was representative of the
epidemic curve of Zika virus infection and that the
epidemic curve for the city of Salvador could be extrapolated to Bahia State.
Seasonal variation of morality rate could also partially explain the excess deaths; however, the strong correlation between the crude mortality rates and the
epidemic curve suggest a true association between the excess deaths and the peak of the epidemic.
Although no obvious source of norovirus was determined, the
epidemic curve and laboratory data were consistent with a single contamination event such as fecal incontinence that occurred on either Friday night or Saturday morning.