ast Class SARS Feedback Structure Population Population susceptible infected to SARS with SARS infection recovery rate rate B + R depletion contagion recovery Contacts between infected and uninfected people 上海充通大￥ Shanghai Jiao Tong University+ - Population susceptible to SARS Population infected with SARS infection rate + Contacts between infected and + uninfected people + recovery rate B + depletion R contagion B SARS Feedback Structure recovery Last Class