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18 June 2018
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Flies carry diseases and pose a threat to your workforce if found on site – and FMs should not be complacent about the risk. David Cross at Rentokil Pest Control offers his advice.

flies istock
Credit: Istock
David Cross is head of technical training at Rentokil Pest Control
David Cross is head of technical training at Rentokil Pest Control

12 May 2017 | David Cross 

While some of us may rejoice at the arrival of warmer weather, spring is not without its challenges for facilities managers. 

It is also the season when many flying pests emerge from hibernation. Adult flies will have spent the winter sheltering in the nooks and crannies of buildings, and in the spring they emerge to find decaying food, animal or human waste to feed on and lay their eggs in.

Flies are more than just an annoyance. They are a risk to human health because they can cause contamination when they land on food, work surfaces or equipment. These insects spread diseases such as salmonella and E.coli as they move from one food source to another, while some species of fly can also bite. 

The onset of fly activity presents a good opportunity for FMs to work alongside cleaning staff to ensure that they have the right measures in place to prevent an infestation. It is particularly important to protect food preparation and dining areas, as flies are one of the UK’s most common causes of food poisoning. Diligence around the entire premises is advised, as they will make a nuisance of themselves wherever humans go. 

Defending your premises against a fly infestation 

There are practical measures that you can implement to ensure that flies do not enter the building:

Hygiene first 

Flies are typically attracted to unhygienic places, so the first line of defence should be to make sure your premises are clean. FMs should liaise with cleaning staff to design a schedule that covers a regular clean of walls, floors, ceilings and windows. In kitchens and eating areas it’s important that equipment is routinely wiped down inside and out, including fridges and freezers. 

Food waste must be collected frequently, before bins overflow. Kitchen doors should be kept closed when they are not in use and that there are enough eradication measures in place to cope with the arrival of these pests. 

Fly defence units 

Fly screens across windows are a must to stop insects from entering the premises. In addition, fly boxes can help to control the number of flies around external areas of a building. These boxes, which target flies at the adult stage of their life cycle, can be placed on external walls near bins, refuse or waste areas. They contain fast-acting and highly effective insecticides to eliminate flies on contact. This will make sure that the insects are caught during their breeding cycle.

Fly control indoors is equally important for the determined few that manage to find their way inside. Opt for a fly control unit that encapsulates captured flies, rather than zapping them. Units that electrocute flying insects release micro-particles into the air, which can then fall onto surfaces and food. 

Fly control units that transmit ultraviolet (UV) light are useful. Up until now, fly control units have used standard UV tubes, which need to be replaced annually and are energy-hungry. The UV light, generated by LEDs, is transmitted 40 per cent further, extending the unit’s catchment area. 

Final tips 

FMs shouldn’t fall into the trap of thinking that their premises could never host a fly infestation; these pests can lodge anywhere. Whether you are dealing with a fly problem or are looking to prevent one, it is vital to know who to contact. If you are in any doubt as to what methods to use, check with the experts.

Types of fly

There are roughly 7,000 types of fly species in the UK. The housefly and bluebottle are the most common pest species:

1 Housefly 

House flies can be a problem for businesses, especially those that handle food, as they are major carriers of microorganisms that can cause diseases, including salmonella and E.coli. Houseflies feed by regurgitating acids onto food and then proceed to suck up the resultant mush.

2 Bluebottle fly 

Otherwise known as a blow fly, bluebottles can often be seen hovering around dustbins. They are scavengers and are particularly attracted to faeces and dead animals, but are quite happy to feed off of cheese and deli meats too. They feed in a similar manner to houseflies and as a result can also spread microorganisms in the premises.

David Cross is head of technical training at Rentokil Pest Control