Use of National Pneumonia Surveillance to Describe Influenza A(H7N9) Virus Epidemiology, China, 2004–2013
Figure 2. . Number of PUE cases, confirmed influenza A(H7N9) cases reported, and cumulative affected provinces or municipalities, mainland China, March 30–May 3, 2013. *Confirmed A(H7N9) cases reported through the PUE surveillance system. †Cumulative affected provinces/municipalities reporting cases through the PUE system. ‡Cases reported through PUE system. PUE, pneumonia of unknown etiology.