After the central government said this week that it had the pig disease under control in Sichuan province, the epicentre of the outbreak, China's far south is now on high alert after one person was killed and three were infected by the disease that has killed nearly 40 in the southwest.
This suggests that dangerous meat is still being traded across the country.
According to the state media the latest victim of the disease, caused by the Streptococcus suis bacterium, had handled infected pork, and the three infected patients, all butchers, are also likely to have had contact with tainted meat.
Shenzhen is a booming special economic zone just over the border from Hong Kong, and is in the heart of a region hit by a series of health scares, from SARS and bird flu to poisoned eels.
Apparently though no cases had been found among pigs in the province, the other infections were found in three areas of surrounding Guangdong.
Henk Bekedam, a World Health Organisation representative for China, reportedly said that in order to contain the bacterium and other animal-borne diseases, China must focus more on animals.
Bekedam says if human health issues are only dealt with when they strike people, that is already one step behind in building up a defence system.
Almost all of the 200 people who have contracted the pig-borne disease became sick after slaughtering, handling or eating infected swine.
Now strict quarantine controls had been put in place to prevent infected pork from getting out.
Apparently earlier this month, China sealed off a farm in far-western Tibet and inoculated poultry within a 5 km radius after discovering an outbreak of bird flu, believed to be a strain that has killed more than 50 people across Asia and led to the deaths of some 140 million birds.