Durian candies from Wendy's, which caused illness in close to 2,000 children in the Philippines last week, have tested positive for the Staphylococcus bacteria, said the Food and Drug Administration (FDA).
The Wendy's-brand confectionary was sold outside schools by street vendors.
The incident occurred in Mindanao, the country's southern-most large island. After consuming the sweets, the victims complained of stomach cramps, diarrhoea, vomiting, and headaches.
The packaging of the contaminated fruit-flavoured sweets, that come in durian, mango, and mangosteen varieties, did not carry any expiry dates or nutritional facts.
In a statement, FDA acting deputy general director Maria Lourdes Santiago said the symptoms exhibited by the patients confirm the cause of the poisoning outbreak in the Caraga region.
The authorities were initially testing for the presence of salmonella and E-coli bacteria, and mycotoxin contamination. Tests for possible pesticide contamination still continue.
In a public health advisory, the FDA has warned people against consuming Wendy's brand durian candies.
"These backyard industries are not regulated by the FDA.
"The bottom line is, hygiene is often overlooked."
"The public is also warned against unscrupulous selling and distribution of unregistered food items from unlicensed establishments. Consumers must always check products before purchasing that these should be safe, of good quality and within their shelf life," the FDA advisory said.
Filipino authorities have already arrested various vendors who allegedly sold the tainted durian candies.
They are expected to be charged on three counts of violation of the Food Safety Act, Consumer Act, and Physical Injuries in relation to the Special Protection of Children Against Abuse, Exploitation, and Discrimination Act.
Staphylococcus can cause food poisoning when contamination happens at food handler level, followed by improper refrigeration. Other sources of food contamination include the equipment and surfaces on which food is prepared.
