Cape Town - The source of the listeriosis outbreak has been traced, the Ministry of Health confirmed on Sunday.Spokesperson Popo Maja said it would be announced at a press conference at the National Institute of Communicable Diseases at midday."Following intensive investigation and laboratory work undertaken to establish facts on the causes of listeriosis outbreak, the Minister of Health Dr Aaron Motsoaledi will on Sunday brief the media on the progress made to contain the spread of this disease," Maja confirmed in a statement."Minister Motsoaledi will also announce drastic measures that government has decided take in order to contain listeriosis in South Africa."Scientists who have been "working tirelessly" to identify the source of the outbreak would also attend.News24 last month reported that statistics at the time showed the outbreak had claimed a total of 172 lives and 915 laboratory-confirmed cases had been reported to the NICD since January 1, 2017.Gauteng accounted for 59% of reported cases, followed by the Western Cape (12%) and KwaZulu-Natal (7%), the NICD had confirmed.Listeria is a bacterium that is naturally found in the environment - it commonly occurs in soil, water, vegetation and in the faeces of some animals. It can contaminate a wide variety of food types, including meat and meat products, dairy products (unpasteurised and pasteurised), fresh and frozen produce (fruits, vegetables and sprouts) and ready-to-eat products.