Healthcare estates and facilities managers are being advised to implement ‘robust bird control programmes’ following the deaths of two patients who contracted a fungal infection caused by pigeon droppings at a hospital in Glasgow.
NHS Greater Glasgow and Clyde has launched an investigation after the deaths at the Queen Elizabeth University Hospital.
The infection the patients were believed to be suffering from is caused by inhaling the fungus, Crytococcus, which is primarily found in soil and pigeon droppings.
A non-public room, thought to contain machinery, was identified as the likely source.
To protect visitors and staff facilities, those in charge of a building’s maintenance should not overlook bird control as part of an effective onsite pest management programme
Commenting on the announcement, a spokesman for the health board said: "Our thoughts are with the families at this distressing time.
"Due to patient confidentiality we cannot share further details of the two cases.
"The organism is harmless to the vast majority of people and rarely causes disease in humans."
He confirmed a small number of vulnerable paediatric and adult patients were receiving medication to protect them against the airborne infection.
And portable HEPA air filter units have been installed in specific areas as an additional precaution.
Teresa Inkster, lead consultant for infection control at the hospital, said: "Cryptococcus lives in the environment throughout the world. It rarely causes infection in humans.
"People can become infected with it after breathing in the microscopic fungi, although most people who are exposed to it never get sick from it.
"There have been no further cases since the control measures were put in place."
And she said experts were continuing to monitor the air quality.
"It remains our priority to ensure a safe environment for patients and staff”, she added.
But the deaths have brought the issue of bird, and wider vermin, control to the forefront and have led to calls for action by estates and facilities managers.
Dee Ward Thompson, technical manager at the British Pest Control Association (BPCA) told BBH: “Pigeon droppings can be very dangerous. Ornithosis, Listeria, E-coli and other nasty pathogens can be passed through droppings and by the birds themselves.
“And, when dry, the droppings can become airborne leading to respiratory complaints such as psittacosis, and the cryptococcus fungus.
“While the introduction of effective bird management procedures can present challenges for those tasked with the maintenance of buildings - it is a matter that cannot be ignored.
As well as the public health issues, feral pigeon droppings are also acidic and can corrode and erode metals, stonework and brickwork, she warned.
And there are additional health and safety implications of slips and trips caused by the droppings – and the fact that birds and their nests can support parasites such as mites, ticks, fleas and beetles.
Ward Thompson said: “To protect visitors and staff facilities, those in charge of a building’s maintenance should not overlook bird control as part of an effective onsite pest management programme.”
Pigeon droppings can be very dangerous. Ornithosis, Listeria, E-coli and other nasty pathogens can be passed through droppings and by the birds themselves
But, as all UK bird species are protected by the Wildlife and Countryside Act 1981, including their nests and eggs, she advises contacting a specialist pest management company to help with any plan.
Experts have a host of tools at their disposal to deal with the issue, including modern innovations such as ultrasound emitters, laser technology, and bioacoustics.
Understanding the products and methods can take a good deal of time and research, but a good starting point to work from is the categorisation of control products in two areas - proofing and dispersal,” said Ward Thompson.
“Proofing involves physically excluding the birds from the area to be protected.
“Dispersal consists of creating a sense of danger in the affected area, which causes the birds to leave. This includes scaring them away or re-educating them that the area is dangerous.
“Once these two categories are understood, then the next step is to understand the level of bird pressure, which is essentially the amount of resistance likely to be encountered when re-routing an infestation of birds - categorised as low, medium and high.
“Then other considerations, such as the environment and access, need to be assessed before appropriate control measures are introduced.”
NBC Environment has worked with a number of hospital trusts to address the problem of pigeons, including Peterborough City Hospital.
The hospital had a problem on its rooftop plan machinery structures, which had been infested with pigeons for two years.
A multi-pronged approach was used, including setting up a trapping programme to reduce the population on site.
Following this intervention a major cleaning and situation programme was deployed to remove the mess from the site, with a total of 50 binbags collected.
It is important to understand the level of bird pressure, which is essentially the amount of resistance likely to be encountered when re-routing an infestation of birds - categorised as low, medium and high
The team then installed pigeon netting over the plant machinery to prevent more birds accessing the site.
Bird proofing using netting in this way is deemed 100% effective if maintained and is a long-term solution for total exclusion from the area.
It is also often chosen as it has minimal impact on the aesthetics of a building, being virtually invisible from the ground and it reduces cleaning and long-term maintenance cost.
However, despite the deaths, Professor Hugh Pennington of Aberdeen University said it was unusual in the UK for infections to be fatal.
The epidemiologist added: "It is quite common in other parts of the world, particularly in tropical parts and in the US and in countries like that where they have more problems with this particular kind of fungus."But hospital patients with compromised immunity can be at higher risk of complications.
"When it gets into the bloodstream a lot of people have fairly-straightforward infections and it settles in the lungs, but the big problem with this is that it can cause meningitis and, as we know, meningitis can be a very serious infection,” he added.
Anti-fungal drugs are used to treat the infection, but it can be fatal if it is not diagnosed.
And he said a key priority is stopping the airborne infection from entering a hospital's ventilation system.