Corresponding to Ueno and Masuda, Journal of Theoretical Biology, 254, 655-666 (2008), which is located at
http://www.sciencedirect.com/science/article/pii/S0022519308003512
1. Controlling nosocomial infection
based on structure of hospital
social networks
Taro Ueno1,2, Naoki Masuda3,4
1 Institute of Molecular Embryology and Genetics,
The University of Kumamoto
2 Tokyo Metropolitan Hiroo General Hospital
3 Graduate School of Information Science and Technology,
The University of Tokyo
4 JST Presto
Ref: J. Theor. Biol., 254, 655-666 (2008).
2. Objective of this study
•Control nosocomial infections
•By changing structure of hospital social
networks
•By vaccinating some individuals beforehand
•What is special about that?
•Hierarchical network structure
•Hospital specific antibiotics-resistant
pathogens (e.g. MRSA, VRE).
•Severe results in immuno-deficient patients
•As initiator or booster of epidemic outbreaks
at urban community and world-wide levels
3. Social networks of a hospital
• Data from a community hospital in Tokyo, Japan
• Nodes [頂点]
• (Hospitalized) Patient (Pt) [入院患者]
• Nurse (Ns) [看護師]
• (Medical) doctors (Dr) [医師]
• Links [枝]
• Pt-Ns, Pt-Dr, Ns-Dr, Dr-Dr ← medical record [カルテ]
• (Dr-Dr ← same team)
• Pt-Pt ← same room [同じ病室]
• Ns-Ns ← same ward [同じ病棟]
4. Def of contact network
medical record network
medical
doctor
[医師]
nurse
[看護師]
hospitalized
patients
[入院患者]
5. Hierarchical Structure
[ネットワークの階層構造]
team department [診療科]
room [病室]
ward [病棟]
Dr [医師] Ns [看護師] Pt [入院患者]
37. vaccination
• Constraint: only 20 out of 605 can be vaccinated
beforehand (by assuming R state in the SIR
dynamics at time 0).
• Strategies for selecting vaccinated individuals
• Random [無作為]
• Degree based [次数]
• Betweenness centrality based [媒介中心性]
• High-betweenness individuals are mostly Drs.
Some Ns also included.
• Recalculated betweenness centrality based
39. Conclusions
• The observed hospital social network is small-world and
hierarchical.
• Healthcare workers (particularly Dr) are main transmitters.
[医師が感染を媒介する]
• Intervention: Restricting interaction between Drs and their
visits to different wards is more effective than isolating Pts
in single rooms. [チーム解消, 患者入れ替え > 病室個室化]
• Vaccination: betweenness-based > degree-based. [媒介中心
性でワクチン接種するとよい]
• Mostly doctors, some nurses
• But the effectiveness of betweenness-based vaccination
may not be general for networks with hierarchical or
community structure.