Eighth update on Listeriosis Outbreak in South Africa

National Department of Health

By Dr Lucia Anelich

The NICD has provided the latest update on the listeriosis outbreak in South Africa – attached to this note as at 14 February 2018. The outbreak is across all nine provinces. The cases have jumped from 852 on 06 February to 872 (20 more), BUT with a huge jump from 107 deaths to 164! In summary to date:

The strain that is still most frequently isolated belongs to sequence type ST6. This continues to indicate that these isolates originate from a single source, most likely a food product on the market or a series of food products produced in the same manufacturing environment. The source may even be products that are consistently contaminated from batch to batch by persistent L. monocytogenes in the environment of the facility, particularly if there is no environmental control programme with associated effective cleaning and disinfection in place.
Other statistics in summary (see more in NICD report):
Outcome data is available for 597 of the 872 cases. Of these 597 cases, 164 deaths have been reported which drops the mortality rate slightly from 34% on 25 January and 30% on 06 February to 27.5% on 15 February 2018. This rate is currently (this will likely change as the disease progresses and more cases are traced) 2-7% higher than general mortality rates reported in other countries i.e. 20-25%. Neonates ≤ 28 days continue to be the most affected group.
The source of the outbreak remains unknown. By all accounts, the outbreak has not yet peaked and more cases and deaths can be expected if the source is not found soon.
Industry was also informed that the World Health Organization (WHO) had a team in South Africa a few weeks back to assist the National Authorities and the NICD with this outbreak. A few key facilities had been visited and there is apparently a “strong lead”.