Travelers and STDs

Abstract & Commentary

Synopsis: Travelers as a group are at higher risk for acquiring sexually transmitted diseases (STDs). Travel impacts upon human sexual practices by splitting fixed sexual partnerships, removing social taboos that may inhibit sexual freedom, and allowing for escape from standardized behaviors regarded as acceptable by society. Prevention unfortunately plays a small role, if any, in some travel clinic practices.

Source: Matteelli A, Carosi G. Sexually transmitted diseases in travelers. Clin Infect Dis. 2001;32:1063-1067.

Several studies have reviewed sexually transmitted infection and risk behavior among short-term travelers. The review by Matteelli and Carosi summarized studies that demonstrated the effects of STDs on travelers. In an Australian study, 66% of individuals going to Thailand either specifically planned, or hoped to have, a sexual experience during their trip. In a study from Nottingham, England, 5% of 354 travelers had a sexual relationship and less than one third consistently used a condom. A study from patients at a genitourinary clinic in London found that the rate of sexual exposure abroad was 51% among heterosexual males, 36% among homosexual males, and 20% among women. Casual sex occurred even more frequently among long-term travelers abroad. This represents an important subgroup for which this topic is often overlooked in pretravel counseling.

Several studies have attempted to ascertain objective criteria to identify those travelers who have a higher risk of having casual sexual intercourse abroad. Male sex, single status, age younger than 20 years, traveling without a partner, persons having had 2 or more sexual partners in the previous 2 years, casual users of illicit drugs or excessive alcohol, and visitors returning to the same destination more than twice—all were associated with increased risk for acquiring an STD.

It is difficult to establish the exact risk of acquiring any particular STD at a given destination. STD risks in travelers are mathematically derived from the product of the rate of partner exchange and the prevalence of STDs in the contact population in the destination country. In 1995, the worldwide estimated incidence of curable STDs (ie, gonorrhea, chlamydia, and syphilis) was 150 million and 65 million cases in southeast Asia and sub-Saharan Africa, respectively, compared with 14 million and 16 million in North America and Europe, respectively. These figures do not include HIV, hepatitis B & C, herpes simplex virus, and human papillomavirus.

Matteelli and Carosi concern themselves with the following question: why is there no role for prophylactic antibiotics in preventive treatment of STDs? First and most importantly, chemoprophylaxis may confer a false and dangerous sense of protection. Instead, treatment of STDs should be of high quality and carefully administered on the basis of best available current guidelines. The traveler who acquired and was treated abroad for an STD should again be evaluated to ensure that optimal practices were followed. Matteelli and Carosi maintain correctly that even asymptomatic travelers who had casual sex abroad must be screened for STDs, including infections associated with HIV, hepatitis B virus (HBV), syphilis, Chlamydia trachomatis, and Neisseria gonorrhoeae.

Comment by John D. Cahill, MD, & Maria D. Mileno, MD

STDs are an important part of travel medicine that can too easily be overlooked. Travelers, and young travelers in particular, are important target populations in the prevention and control of STDs. Travel clinics are surely useful arenas for both education and counseling of individuals who are at higher risk for acquiring STDs. We find the subject is best addressed during a discussion of HBV risk among travelers.

In the currently reviewed article, the risk of acute HBV in travelers was estimated at 8-24 per 10,000 per population per month, with a case fatality rate of 16-48 per million population per month. Travelers who are at increased risk of HBV can be identified and offered the HBV vaccine—if they have either not already received it or have not completed a full series. This is often the case since many travelers in their 20s or older did not receive vaccine at birth or did not have routine HBV immunization requirements for school entry. The risk group for HBV is broad and includes more than those who are at risk sexually, such as long-term travelers whose occupations (eg, medical volunteer work) put them at risk. Travelers who will be abroad more than a month should be offered the HBV vaccine, which might be given on an accelerated schedule (days 0, 7, 21, and 1-year booster).

Matteelli and Carosi note the above risk factors in travelers for acquiring STDs. In the context of summarizing HBV risks, a frank discussion of the presence of other STDs should also occur. Travelers can simply be reminded of the risks, the definition of safe sex practices, and seeking further evaluation if they have had questionable sexual encounters abroad. Besides the devastating effects that acquisition of an STD, such as HIV, can have on an individual, it is clear that travelers in many different categories may be at risk of transporting HIV to their home countries and home environments.