Going on holiday is exciting, but it also means being exposed to all sorts of germs and grime, especially when it comes to your luggage. Your suitcase rolls through airport bathrooms, station platforms, pavements, and public transport, picking up far more than just memories. But how often do we actually need to clean our luggage? And just how dirty is the average travel case?
We wanted to find out, so we partnered with Amy-May Pointer, a microbiologist with a BSc (Hons) in Microbiology, to conduct a study to reveal how dirty our suitcases really are, and which areas of the suitcase are the most germ-infected.
To reveal the bacteria that can be found on our travel bags, our microbiologist sampled a mix of hard and soft-shell suitcases at a busy airport train station. They swabbed two key external surfaces on each travel case – the wheels and the base – to discover how much dirt we could be transferring to hotel beds and our closets when unpacking.
For each case, a sterile cotton bud was used to take a swab, which was then spread onto inoculated agar plates. These were incubated for five days to identify any bacterial growth and find out what our luggage picks up in transit.
If you’ve got a sensitive stomach, brace yourself – the study revealed that our suitcases are teeming with bacteria… and unfortunately, it’s far from the ‘good’ kind.
Which areas of your suitcase are most affected by germs?
Our study revealed that the wheels of our suitcases are the most heavily contaminated with bacteria, with 400 CFU/3 cm² identified, carrying nearly 58 times more bacteria than a public toilet seat. The wheels consistently grew the most diverse and abundant colonies of bacteria and fungi. These ranged from presumptive Staphylococcus species (common skin bacteria) to Serratia marcescens (often found in moist environments like bathrooms), and even large, black fuzzy moulds (such as Aspergillus species).
The microbiologist, Amy-May Pointer says: “The testing confirmed that suitcase wheels are by far the dirtiest part of a traveller’s bag. In fact, every wheel sample ranked among the highest in bacterial and fungal contamination and diversity. The wheels of your suitcase are essentially rolling through a world of germs and carrying a whole ecosystem with them, and make constant contact with all kinds of surfaces – pavements, streets, airport bathroom floors, train station platforms and rarely (if ever) get cleaned.”
The microbial mix found on suitcase wheels also included presumptive coliforms, suggesting faecal contamination, likely picked up from bird droppings, restrooms or dirty public floors. Even more unsettling was the presence of black moulds, with colonies characteristic of Aspergillus niger and Penicillium, which are linked to musty odours, respiratory irritation, and can trigger allergies.
With suitcase wheels touching all sorts of floors, this may be unsurprising, but given the fact that many of us choose to place our suitcases on hotel beds or tables to unpack – this highlights the bacteria we could unknowingly be coming into contact with.
The second most bacteria-contaminated part of your bag is the base, with around 350 CFU/3 cm² identified. The base of your case might be in contact with the floor when your bag is not being rolled around, and therefore picking up unwanted germs, such as Bacillus spores or even black moulds. Soft-shell cases tend to have a higher fungal growth compared to hard-shell cases, suggesting that the soft fabric is more likely to trap moisture and grime.
Shockingly, the research found that an airport luggage trolley handle is also likely to be more contaminated with bad bacteria than a public toilet seat, including presumptive Bacillus species, such as Bacillus cereus, which are known for causing foodborne illness and Staphylococcus aureus (Staph), which is transferred from skin during handling. Touched by hundreds of hands every day, the handle showed a CFU count of 280/3 cm², meaning it carries 40 times more bacteria than a typical public toilet seat.
| Rank | Surface | CFU colonies count |
| 1 | Suitcase wheels | 400 |
| 2 | Suitcase base | 350 |
| 3 | Trolley handle | 280 |
Amy-May Pointer comments: “The fact that suitcase wheels and airport luggage trolley handles carry more bacteria per centimetre than a toilet seat is a shock! We need to encourage better travel hygiene (and perhaps a little more thought the next time we touch our luggage during travel and then reach for a snack).”
So, what types of bacteria are commonly found on our suitcases, and why should they be cleaned?
- Staphylococcus aureus (Staph) – These bacteria are common on human skin and could come from contact with floors where skin debris has settled. While usually harmless on intact skin, Staph can cause infections when getting into skin cuts or food poisoning if it contaminates food. Therefore, you should be careful when handling your luggage and reaching for an airport snack.
- Bacillus species – One type, Bacillus cereus, can cause food poisoning. These bacteria are hardy and hang around on dry, dirty surfaces like pavements.
- Moulds (Aspergillus, Penicillium) – These come from outdoor air, floors, and soil. They are not directly harmful to most people, but can trigger allergies or breathing issues.
- E. coli (presumptive) – This is a faecal bacterium, which is likely picked up from bird droppings or public toilet floors. Most strains are harmless, but their presence is a hygiene red flag.
- Pseudomonas – This can be found in water, soil, and on skin. Some strains can cause infections, especially in cuts or wounds, and can be hard to treat with antibiotics.
- Yeasts (e.g. Candida, Rhodotorula) – These are usually harmless, but can cause infections in people with a weakened immune system.
Commenting on these findings, Amy-May Pointer explained: ”The microbial communities found on the suitcases included skin bacteria, environmental moulds, and some faecal-associated germs amongst others. Most of these organisms are not highly dangerous in everyday settings, but they form a film of general filth. This explains that grimy feel or musty odour luggage can get after multiple trips.
“The key point is that microbes were very diverse, reflecting all the places the luggage had been. It reinforces the recommendation to keep luggage away from clean surfaces like beds and to deep clean it occasionally.”
Top 5 travel hygiene tips to keep the germs at bay
Although those results paint quite a scary picture, it doesn’t mean you shouldn’t get excited about getting your suitcase out of storage. From more regular cleans, to keeping your luggage off the bed, Amy-May Pointer provides her expert tips on reducing the risk of bacterial infection from your suitcase and ensuring you can travel more hygienically.
1. Keep luggage off the bed (& table)
“Don’t put your suitcase on the hotel bed or on surfaces where you eat. Use the luggage rack or leave the bag on the floor. This avoids transferring whatever’s on the wheels or base to the clean sheets where you’ll sleep (or the table where you’ll eat from). Remember, those wheels are likely dirtier than a toilet seat!”
2. Wipe down your suitcase wheels and base after a trip
“A wipe with a disinfectant wipe or soapy cloth on the wheels and base of your luggage can significantly cut down the bacterial load. Especially do this if you know you rolled through a public restroom or grimy streets. It’s a small step that prevents you from dragging bathroom-floor bacteria into your home (and onto your bed). Occasionally, you can do a periodic deep-clean of your suitcase.”
3. Cover the wheels (or the whole suitcase) when indoors
“If you want to go the extra mile, consider using a washable suitcase cover, or even slip shower caps over the wheels when bringing it inside. It might sound silly, but covering those wheels can stop them from spreading bacteria across your carpet or bedding. You could be protecting your sheets from the kind of microbes that include skin-irritating bacteria like Staphylococcus species.”
4. Wash your hands after handling luggage
“We often remember to wash our hands after using public transport or touching restroom doors, but not after lugging suitcases around. If you’ve been hauling your bag through airports, bathrooms, and pavements, treat your hands as if you just touched those surfaces, because indirectly, you did. Wash your hands after handling your bags, especially before you eat or touch your face.”
5. Think twice about what you wheel your suitcase through
“This one is more about prevention. If possible, avoid rolling your suitcase through obviously filthy areas. For example, don’t drag it into the toilet stall if you can help it. The less gunk your wheels pick up, the less you’ll have to worry about later.”
With just a few simple hygiene habits, you can reduce the risk of picking up unwanted germs on your next adventure. But even with the best precautions, illness can still happen while you’re away. For travellers heading abroad, the best way to protect yourself is to buy comprehensive travel insurance to safeguard against the unexpected.
Methodology:
We partnered with Amy-May Pointer, a microbiologist with a BSc (Hons) in Microbiology, to carry out a study in May and June 2025. Ten hard- and soft-shell suitcases were sampled at a London airport train station using sterile cotton bud swabs. Each swab was then spread onto Nutrient Agar (NA) plates and incubated for five days to allow bacterial colonies to grow.
To provide comparison, we also swabbed commonly used public surfaces at the airport – including a public toilet seat, a toilet flush button, and a luggage trolley handle. These samples were processed in the same way: swabbed using sterile cotton buds, transferred to NA plates, and incubated for five days to observe bacterial growth.
Data correct as of June 2025.