BEIJING, July 11 (Reuters) - China, reeling from a series of health scandals, has ordered video surveillance at blood collection centres across the country in a bid to stamp out a persistent black market trade, state media reported on Wednesday.

The order comes after six people were jailed for illegally soliciting blood from migrant workers in the southern province of Guangdong and three blood clinics were closed for falsifying donor records and other malpractices.

The national surveillance system was scheduled to be in place by October, and all blood plasma collection would need to be videotaped to guard against illegal transactions and malpractice, the China Daily said, citing the health ministry.

China has battled to clean up its tainted blood industry, after thousands of farmers in the impoverished central province of Henan were infected with HIV/AIDS in the 1990s through schemes in which people sold blood to unsanitary, often state-run, clinics.

But blood collection scandals from illegal and poorly managed clinics continue to dog the industry and China's deputy health minister on Tuesday conceded that safety worries had not been totally expunged.

In June, China's food and drug regulator said it had discovered fake plasma being used in at least 18 hospitals in northern China.

China executed a former drug and food safety chief on Tuesday for corruption in an unusually swift sentence which will serve as a warning amid a series of food, drug and other health scandals that have stained the "made in China" brand.