A Space-Time Conditional Intensity Model for Invasive Meningococcal Disease Occurrence

A novel point process model continuous in spacetime is proposed for quantifying the transmission dynamics of the two most common meningococcal antigenic sequence types observed in Germany 20022008. Modeling is based on the conditional intensity function (CIF), which is described by a superposition of additive and multiplicative components. As an epidemiological interesting finding, spread behavior was shown to depend on type in addition to age: basic reproduction numbers were 0.25 (95% CI 0.190.34) and 0.11 (95% CI 0.070.17) for types B:P1.72,4:F15 and C:P1.5,2:F33, respectively. Altogether, the proposed methodology represents a comprehensive and universal regression framework for the modeling, simulation, and inference of self-exciting spatiotemporal point processes based on the CIF. Usability of the modeling in biometric practice is promoted by an implementation in the R package surveillance.