Biosafety level BSL4 Animal
As the Federal Research Institute for Animal Health, the Friedrich-Loeffler-Institut (FLI) works on highly contagious animal diseases such as foot-and-mouth disease and swine fever as well as on animal diseases transmitted by blood-sucking insects such as bluetongue disease. These pathogens pose no health risk to humans, but they do pose a risk to susceptible animal species. Therefore, diagnostics and research work are carried out in the highest safety level 4 (BSL4) Animal in order to prevent the escape of pathogens.
For this purpose, the FLI has a large laboratory (287 m2) and animal house complex (630 m2), which is maintained under negative air pressure at all times, equipped in duplicate with high-performance HEPA filters for supply and exhaust air, and monitored technically around the clock. All waste water first is heated to over 100°C inside the building before it is fed into the institute’s own waste water treatment plant. A rendering plant is also integrated.
Since the animal pathogens handled here pose no infection risk to humans, normal laboratory clothing and work wear for animal houses are sufficient for the personnel. Before entering the area, street clothes are taken off and protective clothing is put on when passing the air locks. When working with infected animals, it is mandatory to shower when changing from one compartment to the next and to change clothing again, so that no pathogens are spread within the BSL4 Animal area. Furthermore, showering is mandatory before leaving the safety area. All used clothing items from the area and all other solid waste are sterilized with hot steam. The top priority in the BSL4 Animal area is to protect the environment from the infectious agents handled here.
Biosafety level BSL4 Zoonoses
Zoonoses, infectious agents which can be transmitted between animals and humans, are another research focus of the FLI. There are no vaccines or therapies available against some of these pathogens. Research on such viruses, which are very dangerous for humans, is only allowed in special safety laboratories of the highest safety level (BSL4). To protect the environment from the pathogens handled here, the same measures as in the safety area BSL4 Animal apply. In addition, there are special measures for the protection of persons against possible infections, in particular use of a full protective suit.
The FLI has a BSL4 zoonosis complex of a size of 350 m². The laboratory with material airlock, autoclave room and other usable floor area occupies about 180 m². Unique features in Europe are two animal rooms of 66 m² each, enabling research on Ebola, Crimean-Congo hemorrhagic fever and other BSL4 viruses in large animals such as swine and cattle. Worldwide, such work with large animals is only possible at two other sites: in Winnipeg, Canada, and Geelong, Australia.
Work in the biosafety area BSL4 Zoonoses
Such a BSL4 high containment laboratory can only function under special building technology and safety engineering conditions. The entire BSL4 area is located in a „box in box“ system. This means that it is surrounded by a safety level 3 area. Scientists, technicians and animal keepers must first pass through this area in compliance with the valid safety and hygienic measures before they can enter the BSL4 area. They work in a full protective suit supplied with filtered air via a hose with a safety valve. The suit is inflated to a pressure slightly higher than that in the room, so that no pathogens can penetrate it even in the event of a leak. The entire building is maintained under negative pressure, so that the air flows in and can only get outside via high-performance HEPA filters. The custom-built technical system is protected against failure by providing essential technical elements in duplicate. The technical system is monitored around the clock.
The supply and exhaust air are filtered twice. All waste water collects in the collection tanks below the laboratory and is sterilized directly inside the building before it is fed into the institute’s own waster water treatment plant. The rendering plant is also located in the BSL4 area.
Whether in the laboratory or in the animal house, the employees are in radio contact with a „backup“ outside the BSL4 area at all times. This „backup“ is also trained for work in the BSL4 area and stays in the adjacent buildings in order to assist employees in the BSL4 area from outside and to be able to help in an emergency. When leaving the BSL4 area, the full protective suit is thoroughly disinfected in a chemical shower. Only then employees are allowed to open the suit and take it off.