The ubiquitous nature of microorganisms requires manufacturers to minimize the risk of contamination occurring, by designing quality assurance processes, training, and monitoring of their manufacturing systems. Whilst quality control procedures throughout the manufacturing process can help reduce the likelihood of contamination occurring, this is a continuous process where manufacturers review, refine and improve their procedures on an ongoing basis.

Contaminated products being used in healthcare is well-documented, microorganisms that have been identified include Pseudomonas spp, Salmonella spp, Serratia marcescens, Aspergillus sydowii and increasingly Burkholderia spp, to name a few. Burkholderia cepacia complex (Bcc) is a group of closely related Gram-negative bacteria, commonly found in environments such as water, soil and in association with plants. Bcc are closely related to Pseudomonas species of bacteria, which is also found in similar environments.

Bcc includes at least 20 closely related species such as B. cenocepacia and B. lata and B. contaminans are amongst the Bcc bacteria encountered most frequently as industrial contaminants(Lopez de Volder et al., 2021, Cunningham-Oakes et al, 2021 ). Bcc have also been isolated from non-sterile pharmaceutical products where its detection in the manufacturing process is difficult and product recalls are frequent (Ramsis et al., 2020). A recent review by the Food and Drug Administration in the USA found that almost 40% of contamination reports in both sterile and non-sterile pharmaceutical products were caused by Bcc bacteria.

Outbreaks of infection due to contaminated disinfectants have been reported since 1981 (Berkelman et al., 1981). Since that time, Bcc bacteria have been isolated from various products used in healthcare settings, including eyedrops, ultrasound gel, mouthwashes and pre moistened bathing wipes (Hell et al., 2011, Sommerstein et al., 2017 Zurita et al., 2014,  Ko et al., 2015). This has been attributed to the organism’s ability to survive in the presence of preservatives and disinfectants and in low nutrient conditions. Knowledge in this area is increasing but this is not definitively known though current thinking is that this is most likely through the ability to form biofilm, thus protecting the organism from the biocides and the hostile external environment (Ogonowski et al., 2018).

A recent systematic review by Halifiger et al., (2020) examined 111 Bcc-related occurrences in a variety of healthcare settings. Most of which tended to be of a long duration as the organism can be difficult to identify. It also takes time for the cause to be determined due to the large number of potential sources to be examined. Importantly, the authors highlighted that none of the reports described whether the manufacturing process was assessed for the cause of the contamination and what steps were undertaken to enhance contamination prevention at the production site to prevent a future recurrence and to provide assurance of quality for future products (Halifiger et al., 2020).

Manufacturers are continuously revisiting the microbiological controls and the measures they have in place to minimise the risk of contamination by microorganisms and this includes the risk of Bcc product contamination occurring. A part of this is being able to detect for the presence of B. cepacia complex species in tested samples. The publication of USP 60 which requires the use of selective media for initial isolation of Bcc is a step in the right direction. But USP60 (or any other published standard) does not provide methodology for species level identification.  

Incorrect species level identification of industrial contaminants, particularly with the closely related Bcc group is a problematic issue (Cunningham-Oakes et al, 2021). Advanced microbial identification strategies should help identify and minimise the risk of Bcc-contamination. Sharing of best practice in prevention and process improvements amongst companies and within industry groups, leveraging expertise from academia and regulatory authorities will further ensure rigorous preventative measures are in place.