A BIOCONTAINMENT DEVICE FOR THE HOUSING OF LABORATORY

RODENTS

Technical Field

This invention is for the technical field relating to the biocontainment and housing of rodents, such as laboratory rats, mice and guinea-pigs, with or without the use of biological pathogens.

In particular, the invention refers to an innovative biocontainment device, which provides efficient internal ventilation to ensure the rodent's survival, but which, at the same time, provides perfect isolation so as to prevent the outflow of pathogens from said device, thus eliminating the risk of infection to staff, the work environment and the external environment.

Background Art

Containment device for the housing of laboratory animals, such as small rodents have been around for some time now. Some of these devices have been developed to contain biological risk (biocontainment) , which may be constituted by pathogens (e.g. virus and bacteria) inherent to the animal housed within or used in the experimental stages for example.

Such devices, generally in box form, usually have an upper part that can be removed from the lower part, that when coupled, delimit the internal rodent containment volume. Inside, the volume is generally divided into separate parts by a grille-like device in a metal or plastic material. The rodent is housed in the lower part, while the upper part is used for the placing of food and one or more bottles of drinking water. The rodent can access the necessary amount of food for its survival through the grille. Broadly speaking, the rodent can thus be housed in the device for around seven days without any need to change its food, water and litter. The device is subsequently opened and the rodents transferred to a new device with new food, water and litter.

If durable and reusable, the previously used device can be decontaminated and sterilised; if disposable, i.e. single-use, the device can be disposed of.

Decontamination and sterilisation is generally carried out through a physical process in known systems, such as autoclaves, at high temperature and under pressure .

In order to ensure the rodent's survival, modern containment devices, both of the durable-reusable and disposable varieties, have two openings for the circulation of air, one being an air inlet and the other being an air outlet.

These devices are placed onto shelf-like structures, which are each connected, through air inlets and outlets, to a ventilation unit.

The ventilation unit usually comprises a ventilation pump, which is connected to the sole air inlet to channel air into the device, and an aspiration pump, which is connected to the sole air outlet to channel exit air out of the device. The air thus circulates from the inlet towards the outlet through the chamber that houses the rodent .

An initial technical problem inherent to this type of device relates to the fact that the circulating air, drawn outwards from the chamber by the aspiration pump, is expelled into the external environment at a distance. This air may contain pathogens and allergens that are harmful to both man and the environment.

In order to overcome this technical hitch, a filter has been designed that can be either applied to the aspiration unit or directly to the air outlet of each device.

The presence of a filter on the air outlet ensures that the air expelled by the pump into the external environment is essentially free of harmful pathogens while, at the same time, the ventilation pump that blocks the air inlet, prevents pathogens from being expelled therefrom.

The biocontainment devices is therefore essentially isolated.

There are nevertheless two further technical hitches associated with this improvement.

The first is due to the fact that although a ventilator that injects forced air, blocks the air inlet when in operation thus preventing pathogens from being released, it nevertheless creates severe complications of a structural nature in the biocontainment device. In addition, isolation is conditional on the ventilation system injecting air into the device. Should a blackout for example block the ventilation pump, even temporarily, then there the pathogens will be freely released into the external environment.

It is also necessary to provide an automatic closure system for the two device openings to prevent the external environment from being contaminated when the device is detached from the forced air ventilation unit, for instance to be channelled empty to the sterilisation process or into another chamber for experiments to be carried out on the animal housed within.

In the case of the latter, in order to guarantee the necessary supply of air for the animals' survival during their transfer from one chamber to another, which would otherwise be insufficient due to the complete closure of the device openings, specific auxiliary ventilation systems have also been adopted. However, this solution is also structurally complex as it requires the design and use of said auxiliary ventilation systems.

It is therefore evident that this closure system complicates the construction of said containment devices. Furthermore, during a sterilisation process, the above closures require that the openings in the two halves of the device be opened, which demands particularly complex operator safety procedures.

It is well known that during activities carried out laboratories or containment housing (BSL2/ABSL2, BSL3/ABSL3, BSL4/ABSL4) or where pathogens are used in animal experimentation) usually envisage decontamination of the containment devices and waste material. The containment device and its durable elements, and similarly, food residues and litter, are generally decontaminated before the start of other preliminary activities and other activities preliminary to reutilisation or packaging prior to final elimination.

Decontamination is generally carried out by physical methods, e.g. steam/heat by means of autoclave. This procedure generally envisages at least the opening of the two halves of the device or, in addition thereto, the preliminary emptying of the contents of the device (such as litter or food residues), followed by more or less burdensome activities relating to the suitable packaging of the aforementioned residues and the various parts of the device to enable activation of an effective decontamination process, in an autoclave, for example. Especially complex safety procedures, risk control and operator protection activities must be in place for these activities to be carried out, so as to prevent exposure to infectious pathogens present in the food and litter components, materials and residues inside the containment device .

Disclosure of invention

The scope of this invention is therefore to provide a biocontainment device for the housing of one or more laboratory animals, preferably rodents, which is perfectly isolated from the external environment in all operating conditions, without the need for complex supplementary systems that ensure such isolation.

In particular, the scope of this invention is to provide a biocontainment device that is structurally simple and which does not therefore require supplementary automatic closure systems for the air inlets and outlets in order to guarantee the water-tightness of the container itself when detached from the ventilation/aspiration unit.

A further scope of this invention is to provide a biocontainment device that does not require the use of auxiliary ventilation systems when the device is detached from the primary ventilation unit.

This invention also aims to provide a biocontainment device that guarantees the efficient inlet of air without requiring the inlet to be connected to a supply ventilation unit so as to guarantee forced circulation of air inside the device itself, while at the same time preventing the external release of pathogens.

These and the other scopes are thus achieved with this biocontainment device (1) for the housing of one or more laboratory animals as per claim 1.

In accordance with the invention, the device comprises an inlet (15) to supply air into the device (1) and an outlet (20) to release of air from the device (1) . The application of a first filter (21) is also provided, which is to be placed in said outlet (20) to prevent pathogens from being released from the device (1) into the external environment.

In accordance with the invention, the inlet also has its own filter ^' element (16) .

Both of the aforementioned filters can be of the HEPA (High Efficiency Particulate Air) or ULPA (Ultra Low Particulate Air) variety or can be of a comparable high- filtering capacity variety for the removal of particulates from the air. These types of filters allow perfect and effective isolation from the external environment.

It is now clear that all of the invention's set scopes have been achieved.

In particular, the device is now isolated from the external environment by two filters (16 and 21), each placed at an opening. In this respect, a dedicated forced ventilation system or unit to supply air into the device through opening 15 is no longer necessary. Air circulation is adequately guaranteed by the openings in each of the filters. In this respect, not only is the system structurally simplified but the technical problem of contamination in the event of breakdown of the ventilation unit, is resolved.

There is also no need for closure systems for the openings that isolate the device from the external environment when the ventilation and aspiration unit is detached, let alone for auxiliary ventilation/aspiration systems .

Now, in accordance with this solution, said biocontainment device can be connected to a single aspiration unit and is thus structurally simpler. Indeed, when connected to the aspiration unit, the device is ideally maintained at a negative internal pressure compared to that of the external environment. The aspiration system draws air from the rear 20 of the device to which it is connected. This action creates a flow of air from the external environment that is drawn into the device through the inlet 15. The air is released from the device through the rear outlet 20. In this respect, when connected to the aspiration unit, the device is permanently in primary biocontainment mode and has a negative internal pressure, and thus ensures that the environment is protected from the external environment and filtering inlet air.

Inlet and outlet air thus undergoes two subsequent purifications: the first on entering via inlet 15 and the second on being released via outlet 20; ideally, there should also be a further filtration, again using a HEPA or ULPA filter, before entering the aspiration motor itself, after which the air is expelled from the system. Air can generally be expelled into the work environment or may be suitably connected to the outside of the building.

In addition, on detaching aspiration, both filters effectively prevent the release of harmful pathogens without any need for complex supplementary closures systems for the inlets and outlet (15, 20) .

In this respect, it is thus clear how, in accordance with this solution, the device not only allows biocontainment to be maintained during the stage that it is connected to the aspiration unit, but also in any other of the many envisaged stages of activities in a laboratory or housing environment (both in basic containment devices such as BSL2 OR ABSL2 and in high containment environments BSL3 or ABSL3 and BLS4 or ABSL4). When the device is in fact disconnected from the aspiration unit, the filters prevent the release of pathogens, while nevertheless leaving both the external communication openings open. In this respect, thanks to the two openings (15, 20) the device is not air-tight but is rather isolated and contained . Said openings with filters, which are not obstructed by any auxiliary ventilation device or closure, now allow for very simple sterilisation without any need to open the device into two halves.

Finally, the device effectively ensures biocontainment and prevents the release of pathogens even in emergency situations such as, by way of example malfunction of the aspiration unit or an electricity blackout. Again, thanks to the presence of a filter at each of the two openings, even if the aspiration system should suddenly cease working, biocontainment is nevertheless guaranteed for a sufficient time to allow the operators to restore standard operating conditions. The supply of air to the animals is at the same time guaranteed because inlet 15 and filter 16 at the front of the device draw air directly from the external environment and not, for instance, from a forced ventilation unit, which could cease working in the event of an electricity blackout or malfunction as described above thus resulting in the death of the animals.

Advantageously, the second filter (16) may be cylindrical.

Alternatively, and again advantageously, the second filter (16) may be flat.

Advantageously, the second filter (16) may be of the at least HEPA or ULPA variety.

Advantageously, the inlet (15) may be cylindrical and of a diameter such that the filter (16) couples inside the inlet with a certain level of mechanical interference.

Alternatively, and advantageously, the inlet (15) may be cylindrical but with a quickfit filter (16) that couples in a releasable manner within the inlet (15) .

For example, said quickfit fittings may, advantageously, envisage at least one flexible clip that flexibly clips onto one edge of the opening (15) .

Alternatively and advantageously, the inlet (15) may be cylindrical but may also have quickfit fittings such that the filter (16) couples within the inlet in a releasable manner.

Even in this example, said quickfit fittings may, envisage at least one flexible clip that flexibly clips onto one edge of the inlet (15) .

A further advantageous alternative may envisage a cylindrical inlet (15) with threading suitable for coupling with supplementary threading of the filter (16) so that the filter can be screwed on/off within/from said inlet .

Advantageously, the cylindrical inlet (15) may be delimited by a cylindrical perimeter wall (15') having multiple perforations for the passage of air in such a way as to protect the filter (16) placed in the inlet by direct contact with the animal contained in the device.

Advantageously, the filter (16) envisages an upper, cylindrical head (17) and an underlying, active part (18) .

Advantageously, the underlying part (18) may be cylindrical with a smaller diameter that the diameter of the upper part (17) and, naturally, with a cylindrical perimeter wall (15') formed in such a way as to house said filter.

Advantageously, said cylindrical perimeter wall (15') envisages a base (15'').

Advantageously, the filter threading (16) may be placed in correspondence with the upper head (17)

Advantageously the filter (16) envisages an O-Ring (22) under the upper head (17) to create a seal when in use and inserted in the receiving opening (15) .

Advantageously, an upper part (2) and a lower part (3) are envisaged, said lower part envisaging a rear side (3 ¹ ) with a predetermined bevel angle to promote airflow.

Here we describe a biocontainment device having an aspiration unit (102) that is connected to the outlet (20) of a containment device (1) as described, in such a way as to create forced air circulation, which flows along the chamber (4) from the inlet and then exits from the outlet (20) of each device (1) .

Advantageously, a support device (100), formed by a number of shelves (101), on which one or more of said biocontainment devices (1) can be placed at various heights, can further be envisaged.

Finally, this also describes the use of a HEPA or ULPA filter to be applied to the inlet (15) of a biocontainment device, as previously described, to isolate the device from the external environment.

Brief description of drawings

Further characteristics and advantages of this biocontainment device, as claimed in the invention, shall become clear in the following description of design forms, provided by way of a non-limiting example, with reference to the attached drawings, in which:

- Figure 1 shows the assembly section of this containment device 1, having two filters 16 and 21 that have been applied to the respective inlet 15 and outlet 20 together with a set of lines indicative of the airflow circulating inside the device;

- Figure 2 provides two lateral views and a top view of the lower part 3 of the device 1;

- Figure 3 and figure 4 further detail the upper part or lid 2 having said openings (15 and 20) on which the filters are placed;

- Figure 5 separates upper part 2 from lower part 3 and shows a section of the various filter components applied, in particular the point where rear filter 21 attaches to ,

O 2013/001552

-lithe receiving opening 20, and also shows a detail of the grille 10 extracted from lower part 3;

- Figure 6 again shows a detail of the upper part with attached filters;

- Figure 7 shows an assembly comprising a support with shelves 101 on which a number of containment devices and air circulation unit have been placed;

- Figure 8 shows a detail of the filter 16 to be attached to the opening of inlet 15;

- Figure 9 again provides a top assembly view of the containment device 1, in which the dotted line shows the position of grille 10, placed within, for the dispensing of food and water. The view of the grille is obtained given that such devices are generally in a transparent material so as to permit observation of the animal inside;

- Figure 10 provides several views of the grille 10;

- Figure 11 provides two assembly views of the device, which sees the lower part 3 coupled to the lid 2 and the formation of the total internal volume 4.

Description of some embodiments

Figure 1 describes a overall section of this containment device 1 pursuant to the invention.

The device, generally in box form, comprises an upper lid 2, which overlaps a lower part 3. The lid attaches to the lower part 3 by means of known closure systems, for example quickfit systems such as fastening clips or screw fastening. The closing systems are nevertheless such as to guarantee adequate air-tightness along the entire fastening perimeter of the lid 2 and the lower part 3 and are such as to prevent accidental opening of the cage. Air-tightness between the lower part and the lid is also guaranteed by the presence of a gasket 7, which runs along the entire fastening perimeter of the two parts of the device. These closing systems, which are well known in the prior art, may be integral to or detachable from the device .

The upper part 2 overlaps lower part 3 forming when in use an internal containment volume 4 for housing the rodent .

For such purposes, as shown in figure 1, a support grille 10 is provided, which physically divides the internal volume 4 into an upper part 5 and a lower part 6. This grille is supported by the presence of two opposing support abutments 8 present for a part of the length of the side delimiting the lower part 3 of the device, as shown in. figure 2.

Figure 10 extrapolates the support grille 10 with two lateral views and a top view. The grille, generally of rectangular or quadrangular design, has an underlying part 12 that closes in the form of a cone or triangle in such a way as to facilitate the rodent's access to the food contained therein.

A perforation 11 allows application of a small bottle or other suitable water container for the rodent in the end section. The grille, as previously mentioned, rests on said abutments 8 of the lower part 2 of the device by means of two lateral wings 12/a that rest on the shoulders 8 when in use.

Figure 2 extrapolates a lateral view, a front view and a rear view as well as a top view of the lower part 3 of the device 1.

The lower part 3 presents, as shown in figure 1 and in figure 2, a rear part 3' with a much more pronounced inclination than that of the front part, with the aim of facilitating internal airflow towards outlet 20. This inclination better directs the airflow directly to the outlet, facilitating the elimination of vapours that endanger the life of the rodent, such as ammonia vapours from urine.

Figure 3 show a front and rear view of the lid 2 of the device, which provide greater detail of the front inlet 15 and rear outlet 20. A lateral view and partial section of the front part of said lid is also shown in figure 4.

The lid 3, as shown in greater detail in figure 4, has an opening 15 in the front part, which can also be inclined in respect of the horizontal line. This inclination also facilitates the influx of the airflow through the opening 20 in the rear part. These openings ideally have a circular base and are such as to house the filtering components 16 and 21 in such as way as to ensure air-tightness between the filter-opening connection and to allow the passage of air only through the filtering element of the filters 16 and 21 themselves.

The front opening 15 is set up in such a way as to form an adequate housing for the filtering element 16, so as to channel air on the internal front part of the device 1 towards the lower part 6. The aforementioned housing protrudes towards the inside of the cage. It ideally comprises an initial cylindrical part, which has, in a possible configuration, an external thread into which the head part 17 of the filter having a complementary thread is inserted. A second cylindrical section 18 is connected at a lower part and has a smaller diameter that that previously mentioned. Said second section develops more internally towards the inside of the cage and serves to contain the active filtering element 18 (see figure 8 of the filtering element) . Both said first and second sections are thus obtained through a cylindrical perimeter wall 15' , which physically creates the housing for the filter and is closed off at the base by means of a base 15''. At least the base, but preferably the base and at least one part. of the perimeter (generally the part at the inferior section) have a number of perforations for the passage of air. Ideally, said perforations are such as to allow, insofar as possible, directed and uniform distribution of inlet air flowing towards the front, internal and lower part 6 of the device 1 itself (see airflow in figure 1). Said cylindrical perimeter wall 15' is such as to prevent the filter 16 from being damaged by the animal contained in the device.

The rear opening 20 has a housing that usually allows a suitable gasket 9 to be interposed in correspondence of the outlet 20 (see figure 6) . The filter 21, in said configuration, presents an internal thread in its end part so that it may be integrally and adequately attached to the cover 2, though the outlet 20, by means of a fixing element 13. Ideally, a gasket 14 (of the O-ring variety for example) may be interposed between the latter and the lid to ensure that the joint is air-tight.

Alternatively the filter may be inserted into the outlet 20 by interference fit.

The front inlet 15 allows the inflow of ambient air into volume 4, via filtration. The rear outlet 20 allows the air in volume 4 to be released, via filtration. On the whole, this condition allows the rodent in device 1 to be protected from any contaminates in the environment external to the device and protects the external environment from contaminants (such as biological pathogens) used for experiments on the rodents. In addition, the airflow that is generated from the front to the back of the device 1 is such as to ensure and maintain the microclimate and the quality of hygiene parameters inside volume 4 necessary to ensure the wellbeing of the animals housed within. Figure 5, as is the case of figure 1, show the invention's essential element.

In particular, these figures show the upper lid 2, which envisages air inlet 15, configured to house filter 16.

Figure 1 shows the filter fastened inside the inlet and through which inlet air in volume 4 is purified thus, at the same time preventing the outflow of infected air from the chamber, as explained in greater detail below.

Figure 6 shows the filters fastened to their respective openings.

Figure 8 provides greater detail of a possible solution for filter 16, which can for example be cylindrical in form (akin to dishwasher filters) , with an upper head 17 that can be coupled with the opening in various ways. For example, in one case, coupling can take place by mechanical interference. In another case, which is the preferred solution, the head 17 can be provided with a basic thread that is coupled to a relative thread in the receiving inlet 15. The underlying part 18 of the filter envisages a cylindrical element that forms the active part of the filter itself. The water-tightness of the filter 16 and housing 15 will be also ensured by means of a water-tight or air-tight element such as a gasket 22, for example. This gasket may be directly integral to the filter 16 or may be independent or integral to inlet 15.

The filter 16 (as is the case with filter 21) should preferably be of a HEPA or ULPA variety.

The upper part 2 also envisages the outlet 20 on which a further filter 21 is attached (see figures 5 and 6) . Said filter may be attached by means of an external fastening element 13, for example, which is also perforated and threaded as necessary. Suitable gasket elements 9 and 14 (the latter being an O-ring, for example) render the joint of the filter 21 to the outlet 20, and therefore the lid 2 of the device, air-tight. The gasket elements may be independent or integral to one or more of the aforementioned elements, such as for example, outlet 20, the filter 21 or the external fastening element 13, where this should be applied.

Figure 7 thus shows a support device 100, formed by a number of shelves 101 on which the various containment devices 1 will be placed at various heights.

The support device 100 also envisages a aspiration system 102 connected to the outlet 20 of each containment device 1. In this way, forced air circulation is produced, which from the inlet flows along the chamber 4 to then exit from the outlet of each device 1.

The aspiration system may comprise a aspiration system, preceded, for example, by one or more filtering modules (HEPA or ULPA capacity) from prior art. The support device complex 100 may have, as per prior art, an electronic operating control system having an easy-to-read display that shows important operating data, such as for example, the internal temperature of the device 1 and the relative humidity, the air supply/flow values and alarms for exceeded the tolerated temperature, humidity and air supply/flow range. The alarms are adequately displayed on said device 100 and may be remotely conveyed to a centralised electronic plant engineering management system.

Although a cylindrical filter at inlet 15 has been described, any other type of filter, e.g. a flat filter, could be fastened to said inlet. In this respect, the receiving inlet does not necessarily have to be cylindrical and may be of a different shape. For example, the inlet could be formed by a number of different perforations on a portion of the flat surface of the lid, blocked by a flat, membrane element (having HEPA or ULPA filtering capacity) that acts as a filter.

Naturally, in all the described solutions, the filters are all interchangeable and thus detachable from the openings to which they are attached.

The construction materials used must be durable, reusable time after time after following a suitable decontamination, sterilisation and reconditioning process, for example. In particular, in the case of a durable device, the construction material of the various components must be resistant to sterilisation using physical agents such as for example, heat/steam and/or autoclave sterilisation process.

Examples of construction materials for parts 2 and 3 of the device 1, include but are not limited to, polysulphone or polycarbonate.

In the case of a disposable, single-use device, it is not necessary for materials on the whole to be resistant to sterilisation by means of physical agents as is the case for the durable device. The device can therefore also be constructed, by way of example, in other plastic materials such as polyethylene terephthalate, polyethylene, polypropylene or similar materials, even if of animal origin.

Having structurally described the essential elements of the inventions, let us now move on, for the sake of clarity, to a description of its operation.

When the rodent is placed inside the biocontainment device for the envisaged time, the containment device is generally placed on the shelves and connected to the aspiration motor 102, which generates forced circulation.

Unlike the prior art, when it becomes necessary to detach the container 2 from the forced air circulation, e.g. when removing the rodent at the end of the experiment or when transporting the device and the rodent contained therein to another location for miscellaneous experimental tests and when decontaminating or eliminating the device 1, detachment does not require that the aforementioned openings 15 and 20 be closed since the air inside the device is prevented from exiting from openings other than the filters 16 and 21. More in particular, any air released from the internal volume 4 towards the external environment is purified by filters and is thus free of the pathogens present inside volume 4.

At the same time, the filters allow purified external air to enter volume 4, thus ensuring the rodent's survival inside the device during transfer and transport, without any need for any further auxiliary forced ventilation devices.

Unlike the prior art, the same protection and biocontainment guarantees are in place in the event of emergency due to the non-functionality of the aspiration system, when the device is placed on the shelve or is in any case connected to the aspiration motor. Indeed, the presence of a filter on each of the two openings, even in the event that the aspiration system should suddenly cease working, guarantees biocontainment for the time needed to restore standard operating conditions. At the same time, the supply of air to the animals is guaranteed, since inlet 15 and filter 16 at the front draw air into the device directly from the external environment.

It is now also possible to decontaminate or sterilise the containment device 1, through known system, such as autoclaves for example, without any need to open the container in its two halves.

The aforementioned benefits of this invention allow for effective and efficient primary biocontainment of the device at all operating stages, thus making it possible to achieve the ideal level of prevention, protection and control of exposure to biological risk, pathogen contamination (viruses, bacteria, etc.) and animal allergens, of personnel, the work environment and external environment.

For the purposes of this invention, biocontainment shall generically mean the prevention of biological pathogens from being released into the external environment and the prevention of personnel, any other persons and the work and, in any case, the environment external to the device itself, from being exposed to such pathogens.