TASK 3: HOSPITAL-COMMUNITY INTERACTIONS: assess the risk of pathogens diffusion from hospital to community and vice versa.

Task leader: Pascal Crépey ,  in collaboration with partner 1 (MESuRS) , partner 3 (EHESP) and partner 4 (CCLIN)

Recent experiences with MERS-CoV, SARS and Ebola underlined the vulnerability of healthcare settings to infection coming from the community. Conversely, multi-resistant bacteria such as MRSA or CRE, which remained mostly limited to healthcare facilities for a long time, have been more and more documented within the general population. Hence, emerging pathogens can no longer be considered as bound to a specific setting, and studies modelling their nosocomial spread have to consider potential links with the community through patient discharges, admissions, and readmissions but also through healthcare workers and visitors. Systematic analysis of the PMSI database will allow dividing the French territory into areas connected to specific hospitals. A patch diffusion model calibrated for different pathogens, including multi-resistant bacteria and airborne transmitted viruses, will then be developed.
For some pathogens, like CRE or MRSA, healthcare settings can be considered as the initial source of community infections, while for others like SARS or Ebola, they act as catalysts which magnify the epidemics, targeting particularly vulnerable or exposed individuals.