Investigation of ESR meningitis infection case
4 August 2008
Report into the investigation of ESR meningitis infection case of Dr Jeannette Adu-Bobie
The Department of Labour says it is now of the opinion that a scientist who contracted meningococcal disease while working at an Institute of Environmental Science and Research (ESR) laboratory probably contracted the disease from the laboratory in the course of her work.
The Department has also apologised to the scientist, Dr Jeannette Adu-Bobie, for originally finding that she was not infected at the laboratory. Dr Adu-Bobie, a visiting specialist working at the Meningitis Vaccine Antibody Testing Laboratory at ESR Kenepuru, contracted Neisseria meningitidis in March 2005. Department of Labour Chief Adviser Occupational Health Dr Geraint Emrys has reviewed the department's original investigation, which concluded it was "extremely unlikely" Dr Adu-Bobie was infected at the ESR laboratory.
In a report released today Dr Emrys said that, like the original investigators he was unable to identify exactly how Dr Adu-Bobie was infected or find any faults with ESR's safety systems that could have led to the infection. "ESR's safety systems conform to international best practice and no failure of these systems has been identified."
However, there was no compelling evidence to suggest she was infected anywhere else. "Given the circumstances, it is my opinion as an occupational health specialist, that on the balance of probabilities Dr Adu-Bobie was infected at the laboratory.
The cause of this infection remains unknown." Department Regional Manager Mike Munnelly has informed Dr Adu-Bobie of the new conclusion, and apologised for the distress the original finding may have caused. "I regret the failure of the original investigation to reach what now appears a reasonable conclusion and apologise for any distress this may have caused. We acknowledge the ordeal that this has been for Dr Adu-Bobie, and appreciate that she wishes to ensure no other scientists suffer as she has."
Dr Emrys said the original investigation didn't miss any key evidence that could have identified the cause of the infection, and correctly found that there were no faults with ESR's safety systems or grounds for any enforcement action by the department. Information considered during his review included new research on whether there is an increased risk of infection for laboratory staff, and a new ACC-commissioned report that concluded that the balance of probabilities overwhelmingly suggested that Dr Adu-Bobie contracted meningitis disease from her work at the ESR laboratory.
Dr Emrys said the research on lab-acquired infections was discussed in a report released by the department last year, Review of Laboratory Practices in Handling Neisseria Meningitidis. The report – which included input from New Zealand and international scientists - concluded that the safety standards recognised in New Zealand laboratories were consistent with international recommendations, and there was no clear or urgent need for change.
That view has not changed, Dr Emrys said. The ACC-commissioned report, by Dr Mark Thomas, Associate Professor in Infectious Diseases University of Auckland, confirmed the original investigation findings that the strain of the organism that infected Dr Adu-Bobie was indistinguishable from the one she worked with in the laboratory and the epidemic strain present in New Zealand.
But it provided new information – that four of the five cases reported in Wellington around the same time Dr Adu-Bobie fell ill involved a different strain of the disease. The fifth case was a similar strain but couldn't be confirmed as the same one that infected Dr Adu-Bobie.
Dr Emrys also investigated concerns raised by Dr Adu-Bobie about Neisseria meningitidis being plated out on the bench at ESR (when material is scraped from a sample onto a dish). Handling frozen or liquid samples in this way creates a risk of infection and must only be done in a biological safety cabinet. Dr Emrys said this activity would breach standard laboratory practices, ESR's safety procedures and its instructions to staff.
The plating of solid samples is not considered to pose such a risk. However, he could not identify any supporting evidence that any laboratory worker performed this activity, and he was unable to draw any conclusions about these concerns. Dr Emrys said despite being unable to identify the cause of the infection his advice was that there were no grounds for the department to revisit the case.
He acknowledged the investigation had been prolonged and difficult for both Dr Adu-Bobie and ESR. "ESR has continued to be patient and cooperative through this process despite repeated questioning of an issue that has already been under extensive investigation. I acknowledge the suffering of Dr Adu-Bobie as a result of this terrible infection and her incredible reasonableness and fortitude in dealing with her current situation." A copy of his report has been sent to ESR and Dr Adu-Bobie, and will be posted on the department's website so it can be read by scientists and laboratories involved in similar activities.
Please note that health and safety services, formerly referred to as Occupational Safety and Health (OSH) should now be referred to as the Department of Labour. Summary of Dr Emrys' findings The investigation review has confirmed:
• The original Department of Labour investigation collected all the relevant information available at the time
• The organism that infected Dr Adu-Bobie was indistinguishable from that under investigation in the laboratory
• In a cluster of five cases caused by Neisseria meningitidis in the Wellington region around the same time as this case, four involved a different strain. The fifth case was similar to the epidemic strain but couldn't be confirmed as the same organism that infected Dr Adu-Bobie
• There is evidence to confirm that ESR provided both induction training and supervision
• Safety procedures at the laboratory were adequate (and despite the level of scrutiny) have remained unchanged
• Variances from the safety procedures reported by Dr Adu-Bobie could either not be confirmed or assessed as to their potential to increase risk of infection
• No evidence could be found to confirm variation from safety procedures of plating frozen samples on the bench (scraping material from a sample on to a dish). Such an action would be a deviation from acceptable international practice and increase the risk of infection. Background information In March 2005, a visiting specialist, Dr Jeannette Adu-Bobie contracted meningococcal disease while working at the ESR laboratory Kenepuru, in Porirua. Dr Adu-Bobie has a PhD in microbiology and came to New Zealand to work at ESR's Meningococcal Vaccine Antibody Testing Laboratory (MVATL).
Dr Adu-Bobie had been in New Zealand only 20 days, and at ESR for about seven working days, at the time she contracted meningococcal septicaemia. She was critically ill and required amputation of her legs, left arm and digits of her right hand.
The original investigation into her case concluded that, based on the evidence available, "it was extremely unlikely the infection was lab-acquired". In February 2006, Dr Adu-Bobie presented a journal article to the department suggesting laboratory workers have a higher risk of infection.
In response the department agreed to look into this further. Dr Geraint Emrys, an occupational health specialist who joined the Department after the original investigation, was asked to review the original investigation and see if he could identify the source of her infection.
Why has DoL changed its mind about how Dr Adu-Bobie caught meningitis? This is largely because Dr Emrys, unlike the original investigators, was not trying to find "evidence" for an investigation under the Health and Safety in Employment Act. His focus was to answer the question "where did Dr Adu-Bobie get this disease?" As a result, he could base his conclusions on "the balance of probabilities", a lower level of proof than would be needed for enforcement purposes.
As an occupational health specialist Dr Emrys was also able to offer a professional "opinion" in a situation where there is no conclusive evidence. Dr Emrys' opinion was reinforced by a report from Dr Mark Thomas, Associate Professor in Infectious Diseases University of Auckland.
This confirmed the original investigation findings that the strain of the organism that infected Dr Adu-Bobie was indistinguishable from the one she worked with in the laboratory and the epidemic strain present in New Zealand. But it provided new information – that four of the five cases reported in Wellington around the same time as Dr Adu-Bobie fell ill involved a different strain of the disease.
The fifth case was a similar strain but couldn't be confirmed as the same one that infected Dr Adu-Bobie. Dr Thomas concluded that the balance of probabilities overwhelmingly suggested that Dr Adu-Bobie contracted meningitis disease from her work at the ESR laboratory. Why did the original investigation reach a different conclusion? The original investigation didn't miss any key evidence that could have identified the cause of the infection, and correctly found that there were no faults with ESR's safety systems or grounds for any enforcement action by the department.
The original investigation failed to reach what now appears to be the reasonable conclusion that Dr Adu-Bobie probably got her infection from her work activities at the ESR laboratory. The department regrets this failure and has apologied to Dr Adu-Bobie for the distress this failure may have caused. Are the safety procedures at ESR sufficient?
Dr Emrys has confirmed that ESR's safety procedures are consistent with international recommendations, and staff are adequately trained in these safety procedures. There is no evidence of any failures or deficiencies in ESR's safety procedures.
He also looked at whether the international recommendations for containing dangerous pathogens are robust enough, in light of research provided by Dr Adu-Bobie about several potentially laboratory-acquired infections overseas. Dr Emrys found there was no compelling information to suggest these recommendations were inadequate.
Why isn't the Department recommending any changes to laboratory safety practices? The Department has looked at the international best practice recommendations for managing this organism in laboratories.
These recommendations are agreed by people who are the experts in this very specialist field. ESR is following these international recommendations. Under these recommendations, biological safety cabinets must be (and are) used by ESR scientists working with live meningitis bacteria in situations when aerosols could be formed and inhaled, to reduce the risk of infection.
How did the department review Dr Adu-Bobie's case? The review included:
• Reviewing all the information gathered for the original investigation
• Visiting ESR Kenepuru on three occasions to seek further information, clarification of the information and seek comment on the potential significance of new declarations
• Multiple e-mail communications, phone conversation and a face to face meeting (in London) with Dr Adu-Bobie.