As the tally of H7N9 cases passes 150 (n=151 since Feb-19-2014, 321-days), crofsbogs has picked up on an environmental sample from a second live bird market (Nanchao market) that has been confirmed as positive for H7N9 by Center of Disease Control and Prevention (CDCP).
This time we learn that nucleic acids were detected so RT-PCR methods are in use, at least in Zhuhai city, a prefecture-level (between less populated than a Province but more than a County) city on the coast of Guangdong province bordering with Macau.
Was RT-PCR in use during those huge poultry screening events last year? Tracking back to a post on some of the vast numbers of animals tested (hundred's of thousands) earlier in 2013 it looks like the testing back then was virological (trying to grow virus I presume) and serological (detecting antibody to recent infection by the virus) rather than molecular (PCR-based). I stand to be corrected on that.
Just thinking out loud, but it seems to me that 800,000+ birds had been tested using RT-PCR then we would have had a much better idea of the extent to which H7N9 was distributed across China.
As an aside, the 3 most recent human cases also read like a who's-who of 2013's H7N9 hotspots; Jiangsu province, Shanghai municipality and Zhejiang province.
I'm making some more lines available on my Excel sheet.