Team:Edinburgh OG/HP/Gold Integrated
Integrated Human Practices
-
Expert Perspectives
We interviewed a number of people to learn more about how antibiotic resistance impacts them and how they think our project could fit into their work.
We learnt a lot from the experts we interviewed, especially with regards to the real world uses of PhagED. When we started the project, our plan was for PhagED to be used in spray form to clean hospital surfaces - one spray for the lysogenic phage and another for the lytic phage. While researching the project, we found that antibiotic resistance is as much of an issue in the farming world as it is in hospitals, so we also investigated this potential route for PhagED as part of our human practices.
Through discussions with experts from both the healthcare and animal industries, we realised that a spray wasn’t the best way to deploy our system.
In hospital settings, powdered detergents and dissolvable cleaning agents are commonly used instead of sprays. Therefore, we decided to focus on PhagED as a powder rather than a spray. As our computational model demonstrated, the provision of nutrients to the system enhances the ability of the phages to remove resistant bacteria. Nutrient powder could therefore be mixed with the powdered phages to create the most efficient possible PhagED. By encapsulating the powdered phages in different coatings, their rate of dissolving can be controlled - allowing the system to be applied in a single stage while ensuring that the lysogenic phages are the first to contact the resistant bacteria.
Powdered PhagED would also be applicable in farm environments, where it could be used for cleaning equipment etc., but also potentially as a food additive. For a product like this to be viable, it would have to be cost-effective and easily incorporated into current routines and treatments.
Below you can see the key points that we learnt from each expert and how they affected our plans for PhagED.
-
Dr. Beth Reilly - Farm Animal Veterinary Surgeon
-
How often do you see evidence of antibiotic resistance in livestock?
We don’t test for resistance often as farmers don’t have a lot of money, so it isn’t that common you would go round culturing for resistances. Therefore there is a lot of antibiotic resistant bacteria that we don’t see, but it is actually much more common than you realise. For example farms are never that sterile, there are flies everywhere and dust in the air etc makes it hard to keep control over bacteria. Also, often ‘bad’ farmers try to save money by halving the dosage or sharing it between two animals, again increasing chance of resistance. As giving an animal lots of small doses is really time consuming (e.g. farmers have to catch the animal) often we prescribe a single high dose of antibiotic for an infection. This means there is a longer period at the end where the animal is exposed to a low level of antibiotics, which also can increase the chance of a new population of bacteria colonising within the animal and developing resistance. One antibiotic I give has a single dose and works for 7 days, which means it could last in the animal for a further week after the first infection is killed off at a low dose - creating opportunity for new bacteria to gain resistance!
-
How do you sterilize equipment?
Iodine is used to sterilize boots and kit, surgery equipment is autoclaved by vets within a box which is only opened at the site of a surgery. We also carry ‘wet packs’ which is basically a sealed box full of alcohol, in which we can put instruments in so that they are semi-sterile, which can be used if you are doing a ‘dirty surgery’ (say an abyss drain) so you can sterilize a clamp to remove the infection. In terms of milking, there is environmental mastitis (bacterial infection of the udder) which they get from bedding and mechanical mastitis which is passed on through milking, so a lot of farms have iodine or chemical flushes which are circulated through the dairy machines after each cow.
-
Do you think you could use PhagED as part of sterilizing equipment?
Breaking open a box of pre- autoclaved surgery equipment could be seen as counterintuitive and it would no longer be sterile. And whether it would be worth it would depend on how much it would cost, because money is everything to farmers. And it would be something the vets in theory would do which would be added to the farmer’s bill. In terms of the milking machines it’s possible you could add phages to the liners, which in some farms are empty for a couple of hours in a day. For example if a farmer had a very contagious batch of infectious bacteria they may be interested in using it. Or if the farmer could put it on their hands as sometimes the infection travels through their contact with lots of teats.
-
Well we were also considering using PhagED as a soap, so maybe an hour before you interact with the animals you wash your hand with the first liquid containing phages then when you are at the farm site wash it with the other liquid. What would you think of that?
Yes that would work, so we could use it as a sterile surgery prep soap. That would be awesome because the worry is when you do a surgery that you could cause an unwanted infection. So if you know any infection you could cause would be treatable by antibiotics that would be great. So I think I would perhaps more see this working as a hand soap than for sterilizing equipment, as a hand soap would be easy - we currently already have alcoholic hand soaps outside all the pens so it would be relatively easy.
-
How much do you think antibiotic resistance costs farmers?
Each farm is very different in that sense, some farms probably don’t have any resistance as they are very responsible, whereas others resistance issues all the time all the time, so it is difficult to quantify. Antibiotics are one of these things where we are really trying to reduce the usage and avoid using where we can - there has been a big drive for this in my vet teaching. A lot of this plays out in trying to encourage farmers to keep a clean environment and be responsible with their antibiotic use.
-
How do you mostly deliver antibiotics?
We often try to only use spray antibiotics (commonly oxytetracyclines) on cuts rather than inject animals with systemic ones if the farm seems clean. So only on really dirty farms will we give systemic antibiotics. Antibiotic sprays can be found on every farm and every time animals cut themselves people use these. Farmers use this a lot because it’s easy.
Some vets (which I think is bad practice) during a surgery will empty an entire bottle of antibiotics inside the animal. Another really common time we give antibiotics is after a bad calving so you have had to put your hand in to help it along, and you try as much as you can to make sure it’s clean as obviously this is a sterile environment you are going into. The common bacteria which enter a calving from your skin are Step and Strap (Streptococcus and Staphylococcus), which can be very resistant.
One bacteria which is really hard to kill with antibiotics and is commonly the cause of mastitis is Staphylococcus aureus. I’ve definitely seen antibiotic resistance in udder infections but it is always really difficult to know in mastitis whether it was transmitted in the milking machine or from bedding or the air, and whether the antibiotic isn’t working because you picked the wrong antibiotic for the pathogen or the farmer didn’t deliver it or if this is real resistance. So it’s very difficult to know if this is resistance, although sometimes you get farmers saying ‘that drug doesn’t work on our farm’ which suggests this could be happening. However even then we can’t be sure, as they might just not like the drug simply because it is new and they are less confident on how to deliver it, or the antibiotic might alter the milk for longer periods as they can’t sell milk from a cow on antibiotics.
With chickens and pigs a lot of their seed is medicated, which basically makes an antibiotic broth - waiting to be drunk. We are trying to move the profession away from that because the issue with that is if everyone is eating normally they will get the adequate dose of antibiotics. But, if you get sick animal - which is the one that needs the antibiotics, it’s probably not going to eat as much as it should because it’s not feeling very well. So then it gets a half dose of antibiotics, making it much more likely for resistance to occur. And also with chickens they use a lot of spray antibiotics, so they sort of have a mist around the birds. So a lot of heavy uses of antibiotics are here which may be worth looking into.
-
How could you incorporate our product in your practice? Specific areas? Specific equipment?
Where there is resistance that we know of, e.g. udders. For example if there is a farm which we know has a resistance problem for a particular bacteria - a spray for the milk machine could have a market. Although to implement this we you do have to think about how often the milk machines are in use and how long it would have to stay on the equipment between milking - so you are limited in time between calvings. Some large farms also have the parlour in nearly constant use. You could spray the inside of the lining of the teat - which is small and 2-3 cm in diameter.
Also it could be used during calvings, we always give antibiotics post difficult calvings, because normally a lot of fecal material enters and they are usually low in calcium as they are really tired so their cervix muscles don’t close properly. It’s common for vets to go without gloves during calvings so using a hand soap before this for calving and general operations. Although I doesn’t know if there is much resistance there because often you jab them with antibiotics and then if they aren't treated the farmer might go to their own medicine cabinets and jab them with different ones. But definitely some way of using this for calving could be very useful - or just general handsoap - even in hospitals for humans!
-
Do you have any further suggestions for a way of using PhagED?
When a cow is on antibiotics the milk it produces cannot be sold for human consumption. So what a lot of farmers do instead of pouring it down the drain is give it to their calves. Vets are encouraging farmers not to do this because of the potential for antibiotic resistance to occur in calves, but also even pouring liquid laced with antibiotics down the drain is quite irresponsible, so you are meant to contain it for a few days so the drug breaks down. So if you had a powder which you could mix into it the then farmers would love it, because then they wouldn’t have to pour milk down the drain and can feed their calves. And if the bacteria could no longer be resistance then there wouldn’t be any worry with vets of farmers doing this.
Another option could be to use it as part of a treatment we already deliver to cow’s udders before birth when we dry them off (stop milking them ~60 days before calving). It used to be common to treat all the quarters (of an udder) with an antibiotic. But we are now going to a selective dry cow therapy where we only put antibiotics in the quarters that has an infection which requires it. It could be an interesting idea to add a bacteriophage to the teat sealant (a plug at the end of the udder) that we use to seal the teats from bacteria, so that if any infection did get in there (ideally none as you do it aseptically) it would be guaranteed to respond to antibiotics.
-
Would you consider incorporating PhagED into your practice?
We are all working on minimising antibiotic resistance so it would be good to do, as there is this threat that we will no longer be able to treat our animals with antibiotics. So if we could make sure this doesn’t happen by using it I think this would be a really good product.
- Antibiotic resistance is a serious issue that vets are keen to find a solution for, but it is complicated by a conflict of interest with farmers.
- Using PhagED in the form of a spray to sterilize surgery equipment is not that practical. Using it as a soap, incorporating it into treatments or using it as a food additive would be a better application.
- Staphylococcus aureus is also very prevalent in farming as it is in hospitals. Therefore MecA would be a good target to first launch PhagED against. But it would be important for PhagED to have a number of targets to be worthwhile.
Questions on practicality of using our product
What we learnt from Dr. Beth Reilly?
This means there is large scope for using PhagED in their practice as they can be more confident that any antibiotics they prescribe would be less likely to produce resistance, even if farmers cut corners.
As a team we had previously never considered using PhagED as a powder to add to food, but from talking to Dr. Reilly this option seems like an obvious choice for delivering the system, especially as feed is a large area where resistance arises across all livestock. Similarly, adding PhagED to treatments which are already routinely given to livestock was also not something we had thought of, but it seems there is large scope for this. The idea of using this as a soap remains popular.
Predicting which bacteria will cause an infection is very difficult, so if we wanted PhagED to work properly we would need to have phages targeting multiple genes.
-
Andrew McGregor - Scottish Dairy Farmer
-
How often do animals need antibiotics?
I roughly have 400 cattle, 200 sheep, out of the 400 cattle half of them will get antibiotic treatment in a year.
-
Where do most infections come from in cattle?
When the cows become dry (stop producing milk before a calving) half of the herd get get preventative pre-antibiotic treatment, as the udder is the most common area for infections in this period. The feet of our cattle too is very prone to infections.
-
How often do you sterilize equipment?
After every milking they get sterilized. The milking parlour works by having a machine which can milk up to 100 cows at once, where an anesthetic wash of chlorinated alkaline detergent is circulated around the equipment, which should kill the bacteria.
-
How do you contain disease in your livestock?
We have a quarantine centre milking unit, so we milk them separately to ensure they are not using the same equipment as the other ones. We also have a quarantine area, basically a separate tent where we will keep them while they are sick.
-
Have you ever experienced antibiotic resistance in your cattle - i.e. so they needed more antibiotics on top of what they had?
The drugs have always worked in the sense that I have never seen pure resistance, however in the cows sometimes you do see reduced effectiveness of treatment. So they remain ill for longer than expected.
-
We’ve spoken to a vet, and she has some ideas of how to integrate PhagED into farming practice, so I wanted to see if you think they are any good?
Use it in a powder form to add to milk taken from a cow currently on antibiotics, so that it can be given to calves. The vet told me farmers often give this milk to calves as it cannot be sold due to it containing antibiotics.
Incorporating your product as a powder to add to milk is a valid idea with a clear cost benefit of doing it, so that is definitely a possible route you could take with your product. Farmers would definitely be interested! For it to be financially viable it would have to offset the costs of getting new milk for calves; milk current sells for around 25-30p a litre, a calf will drink 4 litres a day so buying in new milk will cost around £1 a day per calf. As the cow still has to be milked the time cost of milking it then throwing it away should also be considered. So if it was in powdered form and costs even as much as 15p per litre it would be worth it for farmers. Having a time delay of adding a second powder however may be off-putting. One company which might be worth talking to about this idea is Britmilk, who currently supply milk to calves with added supplements.
The next suggestion Dr. Reilly had was to use it to spray the inside of the milking device which is attached to the udders.A spray is a big stumbling block if there are two you have to use, one could work at a push, if you had it in the right format. For example a spray is actually not a great way of using it, a modern parlour has milking machine that is very complicated and made of many parts, and we don’t individually spray the equipment. However if you could circulate a water solution fluid through it all that could be more viable. However when we do bacteria testing in the parlour we found it was actually getting cleaned quite well between milkings; the problem was more the cows picking up the bacteria from their bedding or the fields onto their teats, which is why the biggest challenge in terms of sickness for the cows is getting dried off, not during milking. So if you could somehow incorporate this into the drying off stage that might be a better way to use this.
That links in very nicely with the next application suggested by the vet: using PhagED to cover the teat sealant or within the pre-antibiotic (used 60 days before a calving is due).Yes this is where there is large scope for your product. Definitely this seems like the obvious area to use it, this was the first thing that came to my mind when you started talking.
-
What do you think about using it as a soap? So maybe you would wash your hand with the first soap in the morning, then wash it with the other soap when you get to the field, just before interacting with the animals.
I’m afraid that idea is not screaming out at me as something that farmers would pick up! Using it in a powdered form or teat sealant would seem a lot more practical to farmers. I suppose vets might like to use that for operations though, which seems to be another obvious area to use it.
-
Would you have any concerns about using our product?
No I don’t think so, farmers are continually looking for ways to be more cost efficient and streamlined. So when people try and sell us products you just have to convince us it is worthwhile, and ensure it makes any sense. So it needs to be marketed well!
-
Do you have any other suggestions for how we could use or sell PhagED?
Before drying off again the way we try and prevent bacteria getting into the udder is by using antiseptic wipes to clean the teat before we insert it. So incorporating the phages into the wipes could be a really good idea because as I said, that is where most of the infections come from rather than the equipment. A similar line is that the teats do have to be cleaned before milking the cow, as the bacteria they pick up mostly comes from outside the parlour.
Another area this could be used would be to tackle dermatitis (a common infection on the feet). To try stop this we walk cows through foot baths with antibiotics and antiseptic chemicals, so maybe you could treat them by adding the phages to the baths. Although, to feasibly implement this (if you needed to provide two different liquids) you could have a footbath in the day with the first phage and footbath in the night with the second. Or two footbaths directly one after another. Farmers would not adhere to something which means the footbaths have to be taken 2 hours apart, as once the cattle are out for the day they wouldn’t want to bring them in again until they have to in the evening. So having a time delay of even an hour wouldn’t work.
PhagED could potentially be something to sell to companies which directly sell to farmers, if they could incorporate it into the cleaning products that we already use then that would be great. I definitely think adding PhagED to existing products would get the best uptake.
- The biggest limitation is the time delay between the two treatments.
- Most infections in cows for his farm occur in udders and feet, and half of his cows will be given antibiotics in a given year because of this.
- Putting PhagED into a powdered form as a milk supplement would be sought after - if financially viable (<15p per litre).
What we learnt from Andrew McGregor?
If we wanted farmers to take up using PhagED on farms, it would have to be incorporated into practices they already routinely do, which are usually only conducted once. Therefore it would be important to find a way of encapsulating the lytic phages which would be released after a specific delay to allow lysogenic infection to occur first.
There is scope to use PhagED on farms, an easy area would be to add PhagED to current treatments farmers regularly use on their livestock, such as integrating PhagED into drying off treatment, footbaths and udder wipes. This could drastically reduce resistance. This is in agreement with what Dr. Reilly (the vet) said.
If calves could drink milk which has been made ‘safe’ from antibiotic resistant bacteria it would be a win win for farmers, many of whom already practice this anyway despite warnings.
-
Dr Yusuf Ali Lalloo - General Practitioner
-
Where does resistance mainly occur in medicine?
Operating theatres are a big source of antibiotic resistant bacteria - this is because they are a difficult area to keep sterile so it would be useful to have a system to help keep resistant bacteria out. An example which comes to mind is using PhagED for dangerous surgeries like spinal surgeries, where it’s difficult to get antibiotics to reach the infected area. Therefore it would be useful to have something that can ensure the bacteria in that area are only sensitive to antibiotics.
It may also be useful to put PhagED down drains as flushing antibiotics away into the environment is also risky.
-
How is equipment sterilized in hospitals?
Hospitals normally use disposable equipment - they even throw away a lot of metal instruments, producing large amounts of waste. Wipes are often used for surface cleaning. They only autoclave major surgical materials, as it’s cheaper to do this than autoclave large amounts of equipment. Things also often come as kits now for certain procedures. So you have one sterile pack that you open once rather than having packs of scissors etc.
In surgeries patients often have ‘skin preps’, so antiseptic liquids are washed over the site where the surgery will take place. Suppliers normally sterilise that sort of equipment before it comes to the hospital.
-
How does antibiotic resistance arise in hospitals?
As a GP I’ve seen a lot of people suffering from antibiotic resistance - for example, people who had a lot of antibiotics as a child, or who had a gut infection. The more antibiotics people take, the more likely they are to be infected with resistant bacteria. Because of this certain antibiotics in Scotland need to be approved by a microbiologist before they can be used. In hospitals IV antibiotics tend to cause a lot of resistance, so often people who have been treated by these can’t be treated by regular antibiotic tablets and need to have IV antibiotics again.
-
How do you think we could use PhagED in hospitals? We think sterilizing equipment or using as a hand soap could be beneficial.
For hospital use it would make sense to have your product to be added to sterilised equipment before packaging and made by a reputable dealer. The main sources of infections in spinal surgeries etc. arise from bacteria previously living on the patient’s skin or clothes. Thus for skin preps, doctors use ChloraPrep™ applied to the skin, usually in 2 or 3 rounds. So if you could integrate PhagED into that it could be useful too. In terms of soaps, they need to be non-abrasive, hypo-allergenic. Dispensers should ideally be hands-free, one per bed for each patient. So if PhagED fits that criteria it could work.
-
How do hospitals deal with outbreaks of antibiotic resistance?
Deep cleaning resistance-contaminated areas normally take about 5 days. Microbiology departments regularly culture bacteria to check the resistance. In bad instances, the whole room might have to be redecorated - walls, carpets ripped out etc. Deep cleans aren’t super common, but also not super rare. Normally they’re not necessary if you can identify the source of the infection, and procedures for dealing with resistance are improving.
-
How do doctors decide which antibiotics to prescribe?
There are guidelines about which antibiotics to use. Doctors are less “antibiotic-happy” these days. They used to treat the most likely bacteria and culture in the background, but now they wait for a culture before they treat.
-
Summary (click to open)
We spoke to Ali to gain a doctor’s perspective on the antibiotic resistance problem and how our project could help solve it.
He emphasised the importance of removing antibiotic resistant bacteria from operating theatres. These areas are difficult to keep completely sterile, but using phage to remove antibiotic resistant bacteria would ensure that any infections that occur are simpler to treat.
We asked him about current procedures and the places he thought our project could fit best. The skin is a major source of infection during surgeries, so incorporating PhagED into skin preps and soaps could be incredibly useful. Current skin preps are typically chlorhexidine gluconate and alcohol-based, and soaps are also often alcohol-based. Because alcohol can kill certain phages, any soaps we created would have to take this into account. It’s also important that any soaps used are non-abrasive and hypoallergenic. Wipes are often used for cleaning surfaces, so these could potentially be imbued with PhagED - perhaps with one wipe for lysogenic phages and a second for lytic.
We also discussed the current state of antibiotics and antibiotic resistance. Ali sees a large number of people suffering from infections by antibiotic-resistant bacteria, especially patients who took a large number of antibiotics as children or who have previously suffered from gut infections. IV antibiotics are also a major cause of resistance, and patients treated with these can often no longer be treated with standard antibiotics. In Scotland, a number of antibiotics must be approved by a microbiologist before they can be administered, in an effort to reduce their unnecessary use and stop the development of resistance. It is becoming the norm for doctors to wait for culture results before prescribing antibiotics, rather than preemptively prescribing for the most likely bacteria.
- The majority of hospital equipment is disposable.
- Doctors often wait for a culture before deciding on a antibiotic.
- Deep cleaning hospital rooms can be very time consuming (take up to five days) and exhaustive.
- Soaps are found by every bed and have to be universally useable by everyone.
What we learnt from Dr. Yusuf Ali Lalloo?
This means that for us to try and integrate PhagED for sterilizing equipment it would be most beneficial to talk to the companies which produce the disposable equipment for hospitals. Therefore selling it as a spray directly to hospitals to sterilize their own equipment probably isn’t viable.
Therefore if we wanted to ever develop PhagED in pill form with an antibiotic, there would be a high certainty that the correct phages would be delivered, as doctors already know which bacteria are being targeted.
This means removing antibiotic resistant bacteria can be highly time consuming, and thus costly for hospitals. Therefore a product like PhagED could be incredibly useful for reducing the risk of this happening.
If we wanted to integrate PhagED as a soap it would have to be tested carefully to not harm anyone. It may be difficult however to integrate PhagED in this way as the soaps often are alcohol-based, which kills phages.
-
Karine Moore - Hospital Domestic
-
What methods do you currently use to clean surfaces in the hospital? E.g. do you use cleaning sprays, wipes etc.?
For table surfaces/countertops/patients personal tables we use a liquid detergent dissolved in hot water, and use disposable paper towels with one square for each surface. For sinks and toilets we use a powder detergent disinfectant. In toilets it is applied to a wet toilet bowl and used with the toilet brush, and in the case of the sink a square of disposable paper is wet with water and a small amount is put on the damp towel and rubbed into the sink and then rinsed away with water. For floors in standard bedrooms and 6 bed wards we use the same liquid detergent used for cleaning surfaces/countertops/etc and dissolve this with hot water. For normal toilets in standard single rooms and 6 bed wards we dissolve the powder detergent disinfected used on toilets and sinks with hot water. The mop heads we use are fabric and are removable, and machine washed and tumble dried after each shift. These are removed and placed into plastic bags by domestics on shift upon entry into a new ward. PPE (Personal Protective Equipment) is worn at all times by domestics when cleaning, which consists of colour co-ordinated disposable aprons and medical grade disposable gloves, which are removed and replaced after the completion of each area.
For barrier rooms (high infection rooms such as C. difficile, MRSA, bird/swine flu, Hepatitis C) both the surface bucket and mop bucket are filled with a solution comprised of one “chlorine releasing disinfectant tablet with detergent” to one litre of hot water. These are used with the same disposable mop head and paper towels and the same procedure used to clean the room. The same powder detergent disinfectant is used for the toilets and sink. Once a domestic is inside a barrier room (single or 6 bed) they are not able to leave until the room is fully cleaned and remove their PPE as they are leaving the room and place this in the clinical waste bin provided. If the room has an airborne virus this PPE will include a mask alongside the standard disposable apron and medical grade disposable gloves.
In the case of a patient discharge the room is cleaned as a above with the chlorine tablet solution. However as each item is thoroughly cleaned it is removed from the room (this includes bedsides tables, chairs, bins, bed etc) and the floor is mopped with the chlorine solution and scrubbed with a disposable scrubbing pad and scrubber machine. The floor is then mopped again and allowed to air dry. If in a room with curtains or a 6 bed ward where divider screens are in use, these are removed and placed in soluble infection control bags and cleaned by linen staff and are replaced. If the bathroom has a shower curtain this is removed by domestic staff and placed in a bucket with the chlorine tablet solution (1:1 ratio) and allowed to soak for an extended period of time before being rinsed and hung back up.
If there is a blood/urine/faeces/sick spillage this is removed by nursing staff, but is done using the chlorine tablets mentioned above dissolved in hot water at a 1:1 ratio, with the exception of a blood spill where the ratio is 10:1.
-
Does antibiotic resistance impact your work? How often do you see instances of antibiotic resistance? E.g. having to deep clean rooms where infections with resistant bacteria have occurred.
Antibiotic resistance impacts my work as it is the role of the domestic to maintain a safe and clean ward for patients, visitors and staff, and this is harder to achieve if bacteria are resistant to antibiotics and cleaning solutions. I experience instances of antibiotic resistance in every shift I work, as there is a high level of barrier/high infection rooms on my ward and in the surrounding wards on my level. These vary in severity, but a deep clean is always necessary in the room after the patient has been discharged (as mentioned above).
-
What is your opinion of the project? Would you be willing to use this system to clean surfaces and/or your skin? Can you foresee any issues with this system?
I think this project is well founded and could become incredibly useful to NHS staff should it prove successful at rendering bacteria more susceptible to cleaning solutions, especially in the case of MRSA and C. difficile, both of which have high rates of being contracted in hospitals. Visitors and staff are warned about taking extra care when dealing with these cases as cross-contamination can happen easily. For example when dealing with a patient who has C. difficile, not only is it good practice to wash your hands afterwards but it is mandatory, as the hand gels in use do not remove C. difficile from your hands and only washing with hot water and the provided hand soap can do this. If the project was successful it would be incredibly useful to utilize this method in hand soaps and hand gels to minimise the risk of cross infection by staff and visitors, with more focus on hand gels as it mostly the only form of disinfection visitors use (if at all) when entering and leaving the ward. It is standard procedure to wash your hands and use hand gels after dealing with all patients and in between touching difference surfaces, especially in a ward setting. In all wards for all staff it is mandatory to have the hand up to the elbows exposed to avoid cross contamination via clothing.
-
In what other ways do you think antibiotic resistant bacteria can be combated? E.g. alternative cleaning methods, changes in the way antibiotics are prescribed.
I do think that we as a society are too dependent on antibiotics and prescription drugs in general, and would be happy if more patients would be willing to try other methods first before resorting to prescription medication, and it is an approach I have started to adopt myself.
-
Summary (click to open)
Karine has worked as a hospital domestic for a number of years and one of her main duties is cleaning various parts of the hospital including patients’ bedrooms and bathrooms. By speaking to her we were able to gain valuable insights into current cleaning procedures and how our project could be effectively implemented in hospitals.
She encounters infections with antibiotic resistant bacteria during every shift she works, though the severity of infections varies. Rooms where these infections occur are deemed “barrier rooms” and require special cleaning procedures. For these “deep cleans”, domestics wear personal protective equipment including an apron, a mask and gloves, and they are not permitted to remove this PPE and leave the room until cleaning is completely finished.
She typically uses powdered detergents for cleaning surfaces such as sinks, and liquid detergents and disposable mops for floors. For cleaning barrier rooms or spillages of bodily fluids, dissolvable chlorine tablets are used.
- Powders are used mostly for disinfecting surfaces rather than sprays, as spray bottles are easily contaminated once opened.
- They mix the powders with water and chlorine.
- Using PhagED as a soap has huge potential, as soaps are used by all staff and visitors to the hospital.
What we learnt from Karine Moore?
Therefore producing PhagED as a powder would be much more beneficial than a spray.
This means there is scope to develop a method of encapsulating the lytic phage in something which dissolves in water - this would provide the time delay to deliver the lytic after the lysogenic treatment (simultaneous delivery would save cleaning the same room an hour later).
This also means we would need our phages to survive in contact with chlorine. Fortunately research has already been conducted on T7-like phages of Pseudomonas aeruginosa which demonstrates they can survive.
Zhang et al. showed if you mix these phages with chlorine tough biofilms are significantly reduced. Thus this could be a method of simultaneously destroying biofilms and reintroducing antibiotic susceptibility.
Again, we might need to look at how you would implement the lysogenic and lytic phage together, such as having two dispensers or a lytic phage that isn’t immediately active.
