Backpacking offers a great way to visit exotic countries, explore new cultures, and, according to a new study from Australia, indulge in copious amounts of alcohol and sex.

Hollywood, with indie-screen hits like "Spring Breakers," often glorifies "the artful sleaze" that accompanies young and single vacationers. However, there is a dark side to all of this thrill-seeking — including a heightened risk for contracting an sexually transmitted diseases (STDs), given this group's reputation for hazardous alcohol consumption and unprotected sex.

Twenty percent of travelers report having had casual sex with a new partner while in a foreign country, according to the Centers for Disease Control and Prevention (CDC), and casual sex — whether vaginal, anal, or oral — elevates a person's risk for STDs, such as HIV, herpes, and gonorrhea. This trend, not only poses a risk to the travelers, but also to the residents of the host nation that engage in coitus with the visitors.

Researchers at the Queensland Health Ministry sought to measure the public health risk posed by international backpackers to the citizens of Brisbane, a popular tourist destination and the third most populous city in Australia. They identified higher drinking and sexual patterns amongst these backpackers, and nearly one-third of the group reported having sex with an Australian partner.

The study involved 168 backpackers (mostly European), who were given surveys that asked about their drinking and sex habits. This was followed by an urine test for two prevalent sexually transmitted infections: chlamydia and gonorrhea. An almost equivalent number of males and females — 57 percent vs 43 percent — were surveyed, and gender did not appear to factor into sexual and drinking behavior.

Nearly three quarters had at least one night of heavy drinking while on their trip, and one in five reported that they were having more sex on holiday relative to when they were home. Condoms were only used about half the time. Prior to a majority of the sexcapades, alcohol was consumed, and a person's level of alcohol use while on holiday correlated with how many different partners they had and weather they would sleep with an Australian. In other words, more drinks lead to more promiscuity.

"This would suggest that those backpackers extending their stay in Australia as part of a working holiday may pose a more serious public health concern given their greater tendency to have more sexual partners, including Australian partners," said the authors.

Their major concern is backpackers might serve as potential bridges for infection, given many travelers pass through tropical locales that are also hotbeds of infectious disease — like Thailand, Singapore, Cambodia, Laos, and Malaysia — where there is a higher-than-average prevalence of STDs. Indeed, one-third of the travelers in this study had made stops in these countries before traveling to Australia.

The prevalence of chlamydia amongst backpackers (4.3 percent) was not exceptionally higher than what is reported for native Australians (4.6 percent) and no gonoherrea was detect amongst the sample group. However, the authors report that "the magnitude of the risk" might be underestimated, given that they only screened for these two STDs. Indeed, higher percentage of participants (16 percent) reported having at least one STD symptom — discharge, painful urination, lesion, or lump — within the preceding 12 months.

While this study is relatively small, the authors suggest that it paints a multifaceted picture of globetrotting, with regards to sexual disease. While most tourists sleep with other tourists, longer stays increased the likelihood that a person would have sex with a native Australian.

"Public health efforts should be strengthened in the screening and education of those international backpackers who spend longer periods in a host country, given their greater likelihood for having sex with local community members," said the study authors.