  The appearance of a novel coronavirus named Middle East (ME) Respiratory
Syndrome Coronavirus (MERS-CoV) has raised global public health concerns
regarding the current situation and its future evolution. Here we propose an
integrative maximum likelihood analysis of both cluster data in the ME region
and importations in Europe to assess transmission scenario and incidence of
sporadic infections. Our approach is based on a spatial-transmission model
integrating mobility data worldwide and allows for variations in the
zoonotic/environmental transmission and underascertainment. Maximum likelihood
estimates for the ME region indicate the occurrence of a subcritical epidemic
(R=0.50, 95% confidence interval (CI) 0.30-0.77) associated with a 0.28 (95% CI
0.12-0.85) daily rate of sporadic introductions. Infections in the region
appear to be mainly dominated by zoonotic/environmental transmissions, with
possible underascertainment (95% CI of estimated to observed sporadic cases in
the range 1.03-7.32). No time evolution of the situation emerges. Analyses of
flight passenger data from the region indicate areas at high risk of
importation. While dismissing an immediate threat for global health security,
this analysis provides a baseline scenario for future reference and updates,
suggests reinforced surveillance to limit underascertainment, and calls for
increased alertness in high-risk areas worldwide.
