Saturday, 15 February 2014

Zhejiang province leads the way in H7N9 cases and their decline 3-weeks after market closures...

Click on image to enlarge.
It's the Province in China that has seen more H7N9 cases confirmed in human than any other Province (39% of all cases have originated here). 

It reached 50 cases faster in 2014 than 2013. 

It closed its markets back in 24-Jan. And for a little while it kept finding new cases. 

But the past 2-days have see no new cases announced from Zhejiang province. Eerily reminiscent of 2013 sudden disappearance of cases announcements.

If we look at the data by date of onset of illness (pretty much all of the second wave data are this thanks to WHO's reporting and data fill-in) in the chart above, we can see this decline clearly depicted. 

After three weeks of cases nearing 20/week, they've dropped to less than half and then a quarter of that rate. 

Cases are still coming out of Guangdong Province though, but I don't have market closure dates to hand for Guangdong. 

Actually - now I do. Guangzhou's markets have just been shut (Friday, 15-Feb but only until 28-Feb) according to a timely update at Crawford Kilian's H5N1 blog as I write this. Well, that's pretty late in the game and will certainly not be a long term solution. 

I'm surprised that the vocal poultry industry has not yet realised that this sort of money-haemorrhaging close-disinfect-open-restock cycle of events will continue to recur so long as this way of presenting chickens continues. 

Instead of crying fowl (oh yes I did) it would be worth investing that energy and money into educating the population about the freshness and safety of factory-prepared refrigerated/frozen poultry. To my mind anyway. 

Create and promote new oversight and checks and balances to assure the population that the chickens won't be prepared in some dodgy way; about the cold chain; about the benefits in the longer run. 

Of course those assurances would rightly need to include some proof that concerns were unwarranted that poultry were being presented that had:


  • died from disease or poisoning due to pesticide, melamine or grain fumigants
  • been treated with harsh chemicals such as bleach or other disinfectants (credit: anonymous). 
A long road a ahead if this path is ever chosen but it would life-saving benefits both at home and worldwide. Hopefully the industry will find a way to evolve and still make a profit when it is able (or is forced) to see past its grief and current anger at everyone else. 

But back on topic, if Zhejiang is anything to go by - expect to see the Guangzhou (who knows about the rest of Guangdong province?) cases decline steeply within 3-weeks.

Zhejiang remains as my sentinel Province for watching the potential impact of live bird market closures. Last year, daily case numbers dropped by 97-99% within about 3-days of market closure in different Provinces.

Will the drop we've seen recently in Zhejiang be maintained in 2014 as it was in 2013, or will cases take off again? If so and in the absence of data to support any other reason for human cases declining, I think Zhejiang should be used by China's Ministry of Health as an example with which to "educate" the poultry industry on what happens to an emerging lethal infectious disease when you take the live poultry markets out of the equation.

Stay tuned.