Case Studies

Smailholm, Scotland, UK

The Issue: Anthrax Contamination

The Solution: Facility Decontamination with ClO₂ Gas

Background

In July of 2006, a 50-year old man living in the "Borders" Area of southern Scotland died of inhalation anthrax. The death was believed to be the first from inhalation anthrax in the United Kingdom (UK) in over 30 years. Inhalation anthrax, caused by the bacterium Bacillus anthracis (B. anthracis), is rare because it normally isn't found environmentally in a physical form and airborne concentration sufficient to cause illness in exposed individuals.

The progression of inhalation anthrax, typified by the symptoms observed in the Borders area victim, usually begins with the appearance of mild flu-like symptoms. These symptoms often alleviate temporarily, but then regress to a serious shortness of breath, coughing, chest pains and eventual death if left untreated.

The source of the anthrax infection was thought to be animal skins imported from West Africa that were used by local musicians and artists in the manufacture of ceremonial drums and other artifacts.

Engagement

Sabre Technical Services (Sabre) was initially contracted by NHS Borders to investigate the possible presence of B. anthracis spores within the victim's home, as well as in other structures located on his property.

Sabre has extensive experience in this realm, having performed both the assessment and subsequent decontamination of many buildings that were contaminated with B. anthracis spores during a series of bio-weapon attacks that occurred in the USA in late 2001. Sabre also decontaminated the belongings of an individual in New York City who contracted inhalation anthrax in February 2006 as a consequence of his similar work with animal skins imported from West Africa.

The investigation was performed under the direction of the Scotland Procurator Fiscal, the legal officer who performs the functions of public prosecutor and coroner. Leading the medical enquiries were two other Scottish agencies, Health Protection Scotland and National Health Service (NHS) Borders.

Sampling Exercise

Sabre was mobilized by NHS Borders in September of 2006 to assess the victim's property in conjunction with a team of experts from the UK. A week-long surface and air sampling exercise was conducted and the resultant samples were sent to an independent UK government laboratory for analysis. All sampling, transportation and analysis was performed in accordance with "chain of custody" protocol established by the local Scottish police department.

The results of this initial sampling exercise were that all environmental surface and air samples were found to be negative for the B. anthracis organism. As such, the property was cleared of suspicion as a possible source of exposure. The quarantine that had been placed on the property as a precaution was subsequently lifted and possession was transferred back to relatives of the victim.

As the investigation into the man's death progressed, other properties in the Borders area were also implicated as possible sources of B. anthracis exposure, in particular, two properties located in the tiny historical village of Smailholm, Scotland. These suspect properties were the local village hall and a nearby residence with a detached garage.

Sabre was engaged by NHS Borders a second time to perform surface and air sampling for B. anthracis spores at these two premises. The second round of sampling was conducted in late October of 2006. All samples were again sent to an independent UK government laboratory for analysis.

Through this sampling and analysis effort, the house was determined to be negative for B. anthracis spores. However, the detached garage and village hall were both found to be contaminated.

Decontamination

NHS Borders requested that Sabre develop a plan to decontaminate both suspect structures using the gaseous chlorine dioxide (ClO₂) technology it originally developed to treat buildings in the USA that were contaminated during the 2001 bio-weapon attacks. This technology, used at the US Hart Senate Office Building, Curseen-Morris Mail Processing and Distribution Center, Trenton Mail Processing and Distribution Center and the American Media Building, has been deemed the "gold standard" of structural biological agent decontamination by the prestigious US National Academy of Sciences.

Sabre mobilized a complement of specialized equipment from its New Orleans facility to Smailholm via a shipping port in Brunswick, Georgia in early February of 2007. Sabre's decontamination team arrived shortly thereafter to complete the treatment process in late February.

Prior to fumigating the two structures, each was encapsulated in a tent constructed of polyethylene sheeting to prevent any leakage of ClO₂ into the ambient environment surrounding the buildings. Bacterial indicator (BI) spore strips containing high concentrations of a surrogate test organism, B. atrophaeus spores, were also placed throughout the structures to document efficacy of the treatment process.

Following preparatory activities, each contaminated structure was treated to a cumulative ClO₂ CT (contact x time) dose of approximately 9,000 part per million hours. This is the same ClO₂ CT dosage used to treat all contaminated buildings in the USA following the 2001 attacks.

After the fumigation operations had been completed, the BI spore strips were removed from the structures and sent for independent laboratory analysis. Environmental surface and air sampling for B. anthracis spores were also performed again inside both treated buildings.

All BI spore strip and environmental sampling results showed that the ClO₂ fumigation process had been successful in decontaminating the two structures. A "Clearance Committee" comprised of local public health officials that was formed to review all data from the fumigations concluded in mid April of 2007 that the buildings were again safe for re-occupancy by the general public.

Sabre Technical Services is uniquely qualified to provide comprehensive biological agent response planning, sampling, decontamination and clearance services in the USA and Europe. For more information please contact Sabre.