NICD confirms probiotic-linked blood infection outbreak in Gauteng and North West hospitals

The National Institute for Communicable Diseases (NICD) has confirmed an outbreak of a rare bloodstream infection linked to a commonly used probiotic in private hospitals in Gauteng and the North West.

Between February and October 2024, 11 patients were infected with Alkalihalobacillus clausii - a bacterium usually found in probiotic supplements used to treat gut problems such as diarrhoea. The NICD said this is the first outbreak of its kind reported in South Africa.

The cases were identified in eight private-sector hospitals, 10 in Gauteng and one in the North West. Seven patients tested positive more than once during their hospital stay. The median age of those affected was seven years, and just over half were female.

“Although probiotics are often considered safe, this outbreak highlights that they can cause serious infections in hospitalised and vulnerable patients, especially those with weakened immune systems or underlying conditions,” said Dr Noluxabiso Mangwana, lead investigator and South African Field Epidemiology Training Programme (SAFETP) resident at the NICD.

Alkalihalobacillus clausii is generally regarded as a “good” bacterium and is widely used in probiotic products meant to support gut health. However, in this outbreak, it was found to have entered patients’ bloodstreams.

Mangwana said she was part of the response team that investigated the rise in cases after it was reported to the NICD in June 2024. “The novelty of a probiotic-associated outbreak and its clinical implications motivated me to pursue this work,” she said.

Her role included analysing data, reviewing clinical and laboratory records, and contributing to the final report. “This article provides valuable insights into the hidden risks of probiotic use in hospital settings, particularly for vulnerable patients. Readers will gain a better understanding of the balance between potential benefits and risks of probiotics,” she said.

Mangwana added that she hopes the findings will make clinicians more cautious when prescribing probiotics to high-risk patients. “I hope the article will strengthen awareness among clinicians to prescribe probiotics cautiously, especially for high-risk patients. On a policy level, it should support stricter regulation of probiotic manufacturing and quality control, as well as clear clinical guidelines for their safe use.”

The NICD said the investigation underscores the importance of monitoring products that are generally viewed as safe and ensuring infection control in all healthcare settings.

The full report is available at www.phbsa.ac.za.