Gambling With Germs

There’s nothing quite like being in a Vegas casino – the luxurious decor, the jangle of the slots, the palpable excitement as people try to win big. At the same time, casinos around the world have also acquired a reputation as dens of excess, risk, and self-indulgence – an air of shady unsavoriness that many even seek to cultivate as part of their appeal. But something much more unclean than temptation and overindulgence can lurk in the corners of land-based casinos everywhere: potentially dangerous germs. Every time you push a button, pull a handle or slide your chips across the table, you could be picking up millions of bacteria.

Just how many germs are trying their luck at gambling? To find out, we enlisted a team to visit three casinos in Vegas and swab five types of surfaces: slot machine handles, slot machine buttons, $1 chips, $5 chips, and $25 chips. We shipped the samples to an independent lab for testing. The results? Let’s just say the term “gross winnings” takes on a whole new meaning. Keep reading to get the dirt on the germs you could come in contact with every time you walk into a casino.


Dirties Surfaces Casino

When it comes to bacteria levels, which surface wins the jackpot? Cha-ching! The slot machine handles averaged the most viable bacteria cells: 987 colony-forming units per square inch (CFU/sq in). Trailing far behind were the $5 chips (with 343 CFU/sq in), the $1 chips (with 310 CFU/sq in), and the $25 chips (with 167 CFU/sq in). The cleanest surfaces by far were the slot machine buttons, with just 3 CFU/sq in.


Asset2 V2 768x675 1

To get a handle on the meaning behind these bacteria levels, we compared each surface’s germ count with the number of bacteria found on common objects in your home. Four of the five surfaces averaged several times more bacteria than the typical toilet seat, toilet handle, bathroom doorknob, and bathroom light switch.

Last year, more than 42 million people visited Las Vegas. Not everyone came for the casinos – but a single glance at one of the city’s gaming hotspots is enough to reveal that they’re not short on visitors. And Vegas is hardly the whole story: Luxury casino destinations the world over, from Monaco to Singapore, to Macau and beyond, receive millions more visitors every year – carrying germs of global scope. This vast quantity of foot traffic puts a typical casino on a distinctly different level of germ exposure compared with your home. The ever-changing crowds of casino visitors, most at some point touching slot machines or chips, pretty much ensures a steady supply of bacteria.


Asset2 V2 768x675 1 1

here are many kinds of germs in the world, and not all of them are hazardous to humans. However, the vast majority of the germs we found at the Vegas casinos were gram-negative rods, which can be harmful. (One type you’ve probably heard of is E. coli.) We also found lesser amounts of gram-positive cocci (which can cause various infections) and gram-positive rods (which are typically harmless). There were very few bacilli (which are also linked to infections).


111 1

Breaking down the bacteria types on each surface reveals a nasty surprise: The two germiest surfaces – the slot machine handles and the $5 chip – were the most prone to harboring the bad bacteria. Ninety-five percent of the germs on the slot machine handle were potentially harmful and often antibiotic-resistant gram-negative rods. Suffice it to say that you’re unlikely to encounter chips and slot machine handles in the comfort of your home.

The $1 chip and the slot machine buttons both harbored 100 percent gram-positive cocci, which have been linked to infections, blood poisoning, and pneumonia. However, nearly three-quarters of the bacteria on the $25 chips were gram-positive rods, which tend to be harmless to humans. Based on both the germ levels and types our tests revealed, the surface you should be most concerned about touching is the slot machine button.


Bacteria Casino

Just like germs, not all casinos are created equal. Using TripAdvisor ratings as a guide, we chose a low-rated, mid-rated, and high-rated casino to perform our germ testing. Intriguingly, the highest-rated casino contained, by far, the most bacteria – over 20 times more than the mid-rated casino and more than double that of the low-rated casino. It could be that the most renowned casinos, and the ones likely to attract the most visitors, are also attracting all the germs these casino-goers bring along with them.


Germs Types Casino

Even more bad news about high-rated casinos, which are absolutely writhing with bacteria: 100 percent of the germs we found were gram-negative rods, which can be hazardous to your health.

The mid-rated casino fared better: Nearly 60 percent of its germs were gram-positive rods, which generally don’t harm humans. However, another 24 percent were gram-negative rods.

Conversely, the low-rated casino had no gram-negative rods – and nearly 70 percent of its germs were gram-positive cocci, which tend to be harmless.


What happens in Vegas stays in Vegas – but if you touch enough slot machine handles and $5 chips, you might just bring some germs home. But rather than scouring the Strip for the cleanest casinos, you can simply take a few precautions: Wash your hands frequently, don’t touch your eyes, nose, or mouth between spins on the slots, and steer clear of people who appear sick. Another option? Skip the casino altogether in favor of some good old-fashioned online gaming. At, we offer a variety of exciting digital games ranging from slots to blackjack, roulette, and hundreds more. Whether you’re at home or on the go, Casino Room offers desktop and mobile games with more jackpots every day and bonuses for new users.


EmLab P&K did all laboratory testing. Everything presented within this project is averages of all samples within each category. Samples were collected from different level casinos where $1, $5, and $25 chips along with slot machine buttons and handles were swabbed.