0025-7125/92 $0.00

TRAVEL MEDICINE

+ .20

SEXUALLY TRANSMITTED DISEASES AND TRAVELERS David M. Parenti, MD, MScCTM

Millions of Americans travel each year for both business and pleasure. The risk of travelers acquiring sexually transmitted diseases (STDs) is primarily related to sexual contact with new partners during travel. Several diseases such as hepatitis B, human immunodeficiency virus (HIV), and syphilis may also be acquired by other routes such as intravenous drug use or blood transfusion. The usual cultural restraints on sexual behavior may not be operational during travel. At-risk sexual exposures may include those with members of the local population, "commercial sex workers" (that is, prostitutes), or other travelers. Sexual contact may take place in a variety of settings and the risk is dependent on the nature of the sexual contact and the likelihood of infection of the individual partner. The prevalence of STDs in commercial sex workers may be quite high and sexual contact with this population constitutes a substantially higher risk. The spectrum of infection includes Neisseria gonorrhoeae, Chlamydia trachomatis, genital ulcer disease caused by agents such as Treponema pallidum and Haemophilus ducreyi, and viruses such as hepatitis B and the newly described retroviruses. TRADITIONAL SEXUALLY TRANSMITTED DISEASES

Gonorrhea Gonorrhea is one of the most common STDs in either developed or developing countries. Transmission occurs through genital-genital, oral-genital, and anogenital contact. The efficiency of transmission from male to female is approximately 20% following a single episode of vaginal intercourse. The efficiency of other types of contacts is difficult to calculate. Surveys in antenatal clinics in Africa have noted a point prevalence of from 3.4% to 11.2% (Table From the Division of Infectious Diseases, Department of Medicine, George Washington University Medical Center, Washington, DC MEDICAL CLINICS OF NORTH AMERICA VOLUME 76 • NUMBER 6 • NOVEMBER 1992

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Table 1. PREVALENCE OF SEXUALLY TRANSMITTED DISEASES Percent Infected Country

Population

Syphilis'

Gonorrhea

Chlamydia

References

Gambia Ghana Kenya Kenya Swaziland Zambia Zaire Brazil Brazil Costa Rica Netherlands Austria Malaysia Philippines

Pregnant women Pregnant women Pregnant women Commercial sex worker Pregnant women Pregnant women Commercial sex worker Pregnant women Commercial sex worker Women Commercial sex worker Commercial sex worker Commercial sex worker Commercial sex worker

7.2% NR 11% 31%-55% 33.3% 12.5% 16% 5% 30.9% 6.4% NR 0% 13.6% NR

6.7% 3.4% 6.5% 19%-45% 3.9% 11.2% 24% NR NR NR 10% 0.3%-6.9% 14.3% 24.2%

6.7% 7.7% 19.7% 32% NR NR 13% NR NR NR NR 2.2%-10.9% 26.5% 22.1%

63,64 7 55 54,91 69 93,43 79 87,88 29 58 97 102 92 41

'Serologic test for syphilis. NR = Not reported.

1),7· 43. 55. 63. 64. 69. 93 In surveys performed in populations of commercial sex workers, the rates have varied from 5% to 55% in Africa,54. 79. 91 30.9% in Brazil,29 and 0% to 13.6% in Southeast Asia. 41 . 92 The major impediment to therapy in developing countries has been the emergence of antibiotic resistance. In the early 1970s "low level" chromosomally mediated penicillin resistance was noted in several geographically distinct areas of the world, particularly Southeast Asia. By 1976, "high level" plasmidmediated penicillin resistance was present in areas of Africa, Europe, North America, and Asia. The pattern of antibiotic sensitivity has changed over time, in general reflected by increasing resistance to antibiotics. Sensitivity patterns are greatly influenced by antibiotic prescribing patterns, and the prevalence of sensitive strains may actually increase over time if use of the particular antibiotic declines. Reports from the US military in Korea indicate that following introduction of spectinomycin as primary therapy for gonococcal infection, the prevalence of spectinomycin resistance increased from 0% to 7.9% (1981 to 1985), but the prevalence of penicillin resistance decreased from 46.4% to 12.2%.'4 Currently, f3-lactamase producing strains or those with chromosomally mediated penicillin resistance are prevalent in areas of Africa* and Asia (Table 2).24.31. 33, 36, 92 Low level chromosomally mediated tetracycline resistance is common in Africa,"' 17, 70, 83 Spain,81 and Asia,24 and in the 1980s high level plasmid-mediated tetracycline resistance was also detected sporadically,s7. ss, 110 mostly in isolates also producing f3-lactamase. Spectinomycin has been a useful therapeutic alternative, but resistance to this agent has also been noted. '4, 24, 40 Virtually all isolates remain sensitive to ceftriaxone and the quinolones, although occasional resistant isolates have emerged. 48 Therapy of gonorrhea should be based on sensitivity of individual isolates. Uncomplicated gonococcal infection acquired in a potentially resistant area may be empirically treated with ceftriaxone 250 mg IM in one dose, cefixime 400 mg once orally, or spectinomycin 2 g IM in one dose. 2l · 32 The quinolones have also proven useful in a single oral dose: norfloxacin 800 mg,21, 32 ciprofloxacin 500 *References 9, 17, 40, 68, 70, 71, 83, 87, 88.

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Table 2. PREVALENCE OF ANTIBIOTIC RESISTANCE IN Neisseria gonorrhoeae

% Resistance Country

Year

Penicillin'

Tetracycline

Spectinomycin§

Reference

Gabon Kenya Tanzania Djibouti Nigeria Central African Republic Rwanda Zaire Zambia

1985 1984 1984 1988 1985 1984

23% NR 19% 47% 87% 43.9%

28%t NR NR 0% NR 22%t

0% 0% NR 24% NR 0%

83 59 71 40 71 70

1984 1990 1990

52% NR 47.1%

NR NR 0%

71 88 17

Zimbabwe Bahrain

1990 1991

84.4% 65%

0% 0%

68 9

Korea Philippines Hong Kong Hong Kong Malaysia Japan Australia Netherlands Denmark Spain

1985 1989 1987 1990 1988 1989 1990 1988 1988 1987

12.2% 49.3% 45.2% 56% 34.3% 6.3% 21%-100% 14%-20% 5.9% 12%

7.9% 8.5% 0% NR NR NR NR 0% NR 0%

14 24 36 33 92 76 31 110 61 81

Spain Greece

1989 1989

6.7% 19.2%

0% 0%

112 108

NR 10%:1: 32.4%t 0%:1: 15.6%t 69%t 0%:1: NR 47.4%t NR NR NR NR NR 7.3%:1: NR 37%-100%t 0%:1: 1.1%t 7.7%t

*MIC 2" 1.0 f19/ml; includes j3-lactamase and/or chromosomally mediated resistant strains. tMIC 2" 2 f19/ml; chromosomally mediated resistance. :j:MIC 2" 16 f19/ml; plasmid mediated resistance. §MIC 2" 100 f19/ml; chromosomally mediated resistance. NR = Not reported.

mg,21 32 ofloxacin 400 mg,l1 or temafloxacin 200 mg. 38 All of these regimens except spectinomycin are effective in eradicating pharyngeal infection. Therapy should also be included for potential concomitant chlamydial infection. Of the regimens used to treat gonococcal infection, penicillin, tetracycline, and ceftriaxone are adequate to prevent incubating syphilis. 21 , 32 Spectinomycin is not effective and data for the quinolones are insufficient. Chlamydia

Chlamydial urethritis frequently accompanies gonococcal infection, and in fact, may be more prevalent. In Africa, rates of C. trachomatis infection range from 6.7% to 19.7% in pregnant women?' 55, 63, 64 to 13% to 32% in commercial sex workers (see Table 1).54,79,91 In Asia, prevalence in commercial sex workers has ranged from 22.1 % to 26.5%.41, 92 Lymphogranuloma venereum immunotypes are also responsible for genital ulceration seen in Africa (7% to 19% )13,65 and Asia (0% to 9%) (Table 3).106,'09

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Standard therapy for treatment of gonorrhea with penicillins, cephalosporins, or spectinomycin will not eradicate concomitant C. trachomatis infection. Tetracyclines (tetracycline, doxycycline, minocycline), erythromycin, trimethoprim/sulfamethoxazole, rifampin, and ofloxacin, all for ?7 days give cure rates of 85% to 95%.21,32, 3S, 101 CAUSES OF GENITAL ULCERATION

Ulceration of the male or female genital tract is most commonly caused by herpes simplex virus (HSV) in developed countries, but it may have a quite different spectrum in the developing countries of Africa, Asia, or Latin America. This has taken on considerable epidemiologic importance as recent data suggest an association between genital ulceration and transmission of HIV.'s, 78, 79 Genital ulcers are present in 5% of commercial sex workers in Zaire, and both genital ulcers and antibody to H. ducreyi or HSV appear to be more prevalent in those with HIV infection. 79 It is unclear whether this association is a reflection of sexual behaviors that foster transmission of HIV and other STDs or if the ulcers themselves provide a portal of entry for HIV. Several studies have outlined the etiologies of genital ulceration in outpatients visiting STD clinics (Table 3).13,65,77,90,106,109 Chancroid is responsible for a substantial number of ulcers, especially in Africa. 65, 77 HSV causes 17% of genital ulcerations in men and 20% of genital ulcerations in women in Rwanda,13 and is responsible for 6% of genital ulcerations in the Gambia. 65 Seroprevalence rates for HSV-2 in adult populations range from 1.9% to 13.5% in Asia, 7.4% to 27.9% in Europe, and from 27% to 71 % in Africa. 73 Seroprevalence rates are even higher in groups of commercial sex workers: 79% in Japan, 96% in Senega!. 73

Syphilis Syphilis is worldwide in distribution and prevalent particularly in developing countries. Serologic studies (including patients with primary, secondary, Table 3. ETIOLOGY OF GENITAL ULCERATION Percent Infected Number STD Clinics Rwanda Gambia Kenya

110 men 100 women 104 mixed 97 men 89 women 120 men 174 women

Thailand Papua New Guinea Commercial Sex Workers Zaire 62 women Kenya 22 women 'Serologic diagnosis only. NR = Not reported,

Syphilis'

Chancroid

HSV

LGV'

Reference

21% 40% 22% 11% 14% 1% 14%

24% 12% 52% 62% 48% 36% 0%

17% 20% 6% 4% 2% 10% 0%

11% 19% 7% NR NR 0% 9%

13

90 107 109

NR NR

38% 50%

12% NR

NR NR

79 54

65

77

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and tertiary syphilis) have been performed in blood donors and pregnant women, and in high risk populations (STD patients, commercial sex workers). Prevalence rates range from 5% to 55% in Africa* and from 5% to 6% in Latin America (see Table 1). 58,88 In Kenya, seroprevalence is higher in commercial sex workers from lower socioeconomic strata (55%) than in higher strata (31 %).54 Primary syphilis may cause 1% to 40% (see Table 3) of genital ulcers depending on the population studied and location; however, these diagnoses are primarily serologic and probably an overestimate. Transmission occurs by direct contact, with an estimated 30% of contacts of patients with primary or secondary syphilis becoming infected!9 Therapy for syphilis has remained essentially unchanged over the last 20 years. 21,32 Primary and secondary syphilis and early latent syphilis (less than 1 year's duration) are treated with benzathine penicillin G, 2.4 million U IM, in one dose. Late latent syphilis (more than 1 year's duration) is treated with benzathine penicillin G, 2.4 million U IM, weekly for three doses. Alternative therapies for these forms of syphilis include tetracycline, erythromycin, and ceftriaxone. 21 ,32 Because of poor penetration of benzathine penicillin into the cerebrospinal fluid (CSF), intravenous penicillin G (2 to 4 million U every 4 hours, for 10 to 14 days) is recommended for treatment of neurosyphilis. Patients with HIV infection are more likely to have symptomatic neurosyphilis develop and are more likely to have recurrences despite standard therapy. 19, 32 Controversy still exists about which treatment regimens are optimal in the HIVinfected patient; however, higher doses or a longer duration of therapy may be necessary. Chancroid

Chancroid, caused by H ducreyi, is a major cause of genital ulcer disease in developing countries in Africa 13, 65, 77 and Southeast Asia (see Table 3),106 and has been reported in returning travelers from these areas.74 Chancroid is responsible for 12% to 62% of genital ulcers in African, 65, 77 and 35% in Thailand. 106 Chancroid is highly contagious, as demonstrated in a study in Kenya where 58.6% of secondary contacts of men with chancroid became infected. 89 As noted earlier, genital ulcers caused by chancroid may increase the risk of HIV transmission. 18, 78, 79 Resistance of H ducreyi to antimicrobial agents is developing worldwide. Trimethoprim and sulfonamide resistance are quite common, especially in Thailand, and have been associated with clinical failure. 107 Virtually all isolates remain sensitive to ceftriaxone and the quinolones. 1, 5, 59, 107 Therapy should be on the basis of sensitivity of individual isolates. Empiric treatment options for travelers returning from developing countries include ceftriaxone, amoxicillinl clavulanic acid, erythromycin, or ciprofloxacin. 21 , 32, 95 HEPATITIS VIRUSES

Evidence currently supports sexual transmission of both hepatitis Band hepatitis C. 34,44 Antibody prevalence rates for hepatitis B may be well over 50% in some countries of Africa and Asia, and the rate of hepatitis B surface antigen (HBsAg) carriage may be as high as 25%.104 Increased seroprevalence rates have *References 7, 43, 54, 55, 63, 64, 69, 79, 91, 93.

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also been demonstrated in Dutch expatriates (6.2%),47 Belgian expatriates (28%),56 and American missionaries returning from Africa (26%).57 Infectivity of hepatitis B is determined by the presence of HBsAg in the serum and especially hepatitis B e antigen. In recent studies of commercial sex workers in Asia, 6.1 % to 17.9% were HBsAg carriers.41.92 Recently, hepatitis C has also been associated with sexual transmission,34 and acquisition of hepatitis C antibody has also been noted in an expatriate missionary group in the United Kingdom (4% ).50 Hepatitis B vaccine has been successful in preventing hepatitis infection from a variety of sources. Vaccination for travelers has mainly been recommended for health care workers and long-term travelers to countries with high seroprevalence rates. 22 Recently, more widespread immunization programs for infants and adolescents have been recommended. 23 Immune serum globulin may also confer some protection from hepatitis B44 and hepatitis C,45 although this is controversial. RETROVIRUSES

Several retroviruses have now been identified that are transmitted by sexual contact: HIV-1 and HIV-2 and the human T celllymphotrophic viruses (HTLV-I, HTLV-II). Distribution varies geographically and can frequently be linked to certain high risk groups such as commercial sex workers and intravenous drug users. HIV infection clearly poses the most significant threat to sexually active travelers. HIV-1 and HIV-2 Infection

Infection with HIV has now been reported from over 160 countries. Sexual contact has been implicated in approximately 75% of the 100 million infections worldwide. 67 Although the majority of US cases have occurred in homosexual men or intravenous drug users, 60% of the cases worldwide have occurred through heterosexual transmission. 67 HIV -1 infection has also been imported into developed countries by foreign nationals and acquired by expatriates traveling or residing abroad. 75, 105, 113 Recent studies have demonstrated HIV seropositivity in expatriates from the Netherlands (0.4%), Belgium (1.1 %), and Denmark (8.6%).56 Foreign nationals have also imported HIV-2 into the United States, although only a few cases have been reported. 20 A strong correlation also exists between the presence of HIV infection and the presence of other STDs leading to genital ulcers, such as chancroid, syphilis, and HSV!6, 91 Chlamydial infection has also been associated with increased HIV transmission, perhaps owing to cervical friability or the presence of CD4positive mononuclear inflammatory cells in the cervical mucosa during chlamydial infection. 91 The coexistence of STDs, especially genital ulcer disease, may facilitate transmission of HIV or may only be a marker for sexual behavior linked to increased HIV transmission. The epidemiologic pattern of HIV infection is ever changing, and several studies have shown significant increases in prevalence over relatively short periods of time. Prevalence estimates in the general population are based on epidemiologic studies of different groups such as family clusters, pregnant or postpartum women, and unselected blood donors. Samplings of individuals in urban settings in Africa have consistently demonstrated higher prevalence rates than those in rural settings. B, 80, 98 In an urban population in Uganda, 17% of

SEXUALLY TRANSMITTED DISEASES AND TRAVELERS

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the population was infected with HIV-l, compared to 5.7% to 12% in a rural group.8 Prevalence rates are particularly high in some areas of Africa, ranging from 17% to 32%.2,8,98 HIV-2 is confined primarily to West Africa, and prevalence rates seem to be somewhat lower, ranging from 0% to 16%.28 Seroprevalence rates for HIV-l have remained relatively low in Asia; however, they have been predicted to rise dramatically in the next few years, particularly in Thailand and India. 16 Commercial sex workers are at especially high risk of infection. In urban areas of Africa such as Kinshasa (35%)/9 Nairobi (81 %)/' and Butare (88%), III prevalence rates are alarmingly high in this population. Seroprevalence rates in commercial sex workers may reach 12% in Brazil, 29 44% in areas of Thailand,'6 and 69% in Haiti. 114 Male prostitutes also have been noted to have particularly high rates of infection in Brazil (45%)26 and Italy (57%).37 HIV-2 has been found in 3.7% to 37% of commercial sex workers in areas of West Africa. 28,ss HTLV-1

HTLV-l has been described primarily in areas of Japan, the Caribbean, and Africa. It is believed to contribute to the development of adult T cell leukemia in about 10% of those infected. Prevalence rates from 0.08% to 10% have been reported in Africa,3D,60 5% in the Caribbean, and 2.2% to 31.5% in Japan. '2 As expected, commercial sex workers are at risk for this retrovirus as well, with rates of 10.4% in the Gambia 8s and 5% in Brazil. 26 Travel Restrictions

A number of countries (including the United States) currently limit entry on the basis of HIV seropositivity despite condemnation by the World Health Organization and other scientific organizations. 108' There is no evidence that such restrictions will have any effect on decreasing transmission of HIV infection. Requirements will vary for each individual country as to who should be tested, when testing should occur, and whether tests performed in the United States will be accepted. If testing is required, it is usually for individuals planning to stay for more than 3 months. Because requirements may change, individual embassies or consulates should be contacted for details. Carrying equipment for blood drawing is advisable because sterilization of needles and syringes in some countries may be suboptimal. This type of equipment may be available from individual physicians or purchased as "travel emergency kits." PREVENTION OF STOs

Avoidance of high risk encounters clearly is the best measure to prevent STDs during travel. Barrier contraceptive devices, specifically condoms, provide the best alternative to abstinence by preventing direct contact with infective genital lesions or secretions. Barrier methods are more effective when used with spermicides. The success of condoms in preventing STDs is directly proportional to proper and consistent usage and the structural integrity of the condom. Condoms made from synthetic materials such as latex provide a more effective barrier than "natural" condoms made from animal membranes. In experimental models, latex condoms have been shown to be impervious to

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bacteria and to smaller infectious agents such as viruses (HSV-2, CMV, HIV) and C. trachomatis. 39 Natural condoms are not impervious in experimental models to hepatitis B surface antigen72 or HIV. 111 This discrepancy may be related to differences in pore size or resistance to mechanical damage. The clinical use of barrier contraception is clearly less than perfect and is difficult to quantitate. 39. 103 Efficacy studies are primarily retrospective and have included cross-sectional prevalence studies and cohort and case-control studies. Protective efficacy for condoms in preventing urethral gonorrhea in men has ranged from 49% to 75%.5.39.84 Condoms have not been particularly effective in preventing nonspecific urethritis in men (protective efficacy 0% to 15% )5. 39, 84 but seem to have considerable efficacy in preventing transmission of HIV to women (46% to 88% protective efficacy)35. 66. 79. 82. 91 and men. 35 Cervical gonorrhea is best prevented (protective efficacy of 47% to 55% )4,6 with a combination of a diaphragm and spermicidal jelly. Spermicides are agents developed for contraceptive purposes that interfere with sperm viability and include agents such as nonoxynol-9, octoxynol, phenylmercuric acetate, and benzalkonium chloride. Nonoxynol-9 is perhaps the best studied of these compounds. It is a nonionic detergent that disrupts cell membranes of sperm and microorganisms. In vitro inhibitory activity of spermicides has been demonstrated against N. gonorrhoeae,27 HSV, lOO and HIV.'0, 42 The effects of spermicides on infectivity of C. trachomatis in vitro have been variable, with some studies showing an inhibitory effect3• 52. 53 and others showing no significant effect. 51 Spermicides may provide 10% to 87% protection from transmission of N. gonorrhoeae to women 4. 25, 49, 62, 94, 96 but only 21 % to 33% efficacy in preventing transmission of C. trachomatis. 62 , 96 The clinical use of spermicides in preventing HIV transmission during vaginal or anal intercourse is not yet established. Concern also exists that spermicides may in fact cause vaginal irritation that may predispose to HIV transmission. 10 SUMMARY

Sexually active travelers are at risk for a variety of STDs, including traditional venereal infections such as gonorrhea, chlamydial urethritis, syphilis, chancroid, and herpes simplex infection. More recently, hepatitis B, hepatitis C, and HIV-1 have also been described. Risk varies depending on the geographic area of travel and the type of sexual contact. Physicians should be aware of the prevalence of antimicrobial resistance of N. gonorrhoeae and H. ducreyi because this will affect empiric antibiotic therapy. Prevention should focus on proper and consistent usage of barrier contraceptives.

References 1. Abeck D, Johnson AP, Dangor Y, et al: Antibiotic susceptibilities and plasmid profiles of Haemophilus ducreyi isolates from southern Africa. J Antimicrob Chemother 22:437, 1988 2. AlIen 5, Lindan C, Serufilira A, et al: Human immunodeficiency virus infection in urban Rwanda: Demographic and behavioral correlates in a representative sample of childbearing women. JAMA 266:1657, 1991 3. Amortegui AI, Meyer MP: The in vitro effect of chemical intravaginal contraceptives on Chlamydia trachomatis. Contraception 36:481, 1987 4. Austin H, Louv Wc, Alexander WJ: A case-control study of spermicides and gonorrhea. JAMA 251:2822, 1984

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5. Barlow D: The condom and gonorrhoea. Lancet 2:811, 1977 6. Berger GS, Keith L, Moss W: Prevalence of gonorrhoea among women using various methods of contraception. Br J Vener Dis 51:307, 1975 7. Bentsi e, Klufio CA, Perine PL, et al: Genital infections with Chlamydia trachomatis and Neisseria gonorrhoeae in Ghanaian women. Genitourin Med 61:48, 1985 8. Berkley S: HIV in Africa: What is the future? Ann Intern Med 116:339, 1992 9. Bindayna KM, Easmon CS, Ison CA: Chromosomal resistance to antibiotics in gonococci from Bahrain. Sex Transm Dis 18:153, 1991 10. Bird KD: The use of spermicide containing nonoxynol-9 in the prevention of HIV infection. AIDS 5:791, 1991 11. Black JR, Long JM, Zwickl BE, et al: Multicenter randomized study of single-dose ofloxacin versus amoxicillin-probenecid for treatment of uncomplicated gonococcal infection. Antimicrob Agents Chemother 33:167, 1989 12. Blattner WA, Nomura A, Clark JWQ, et al: Modes of transmission and evidence for viral latency from studies of human T-cell lymphotropic virus type 1 in Japanese migrant populations. Proc Natl Acad Sci USA 83:4895, 1986 13. Bogaerts J, Ricart CA, Van Dyck E, et al: The etiology of genital ulceration in Rwanda. Sex Transm Dis 16:123, 1989 14. Boslego JW, Tramont Ee, Takafuji ET, et al: Effect of spectinomycin use on the prevalence of spectinomycin-resistant and penicillinase-producing Neisseria gonorrhoeae. N Engl J Med 317:272, 1987 15. Bowmer MJ, Nsanze H, D'Costa LJ, et al: Single-dose ceftriaxone for chancroid. Antimicrob Agents Chemother 31:67, 1987 16. Braun MM, Heyward WL, Curran JW: The global epidemiology of HIV infection and AIDS. Ann Rev MicrobioI44:555, 1990 17. Bryan JP, Hira SK, Brady W, et al: Oral ciprofloxacin versus ceftriaxone for the treatment of urethritis from resistant Neisseria gonorrhoeae in Zambia. Antimicrob Agents Chemother 34:819, 1990 18. Cameron DW, D'Costa LJ, Maitha GM, et al: Female to male transmission of human immunodeficiency virus type 1: Risk factors for seroconversion in men. Lancet 2:403, 1989 19. Centers for Disease Control: Recommendations for diagnosing and treating syphilis in HIV-infected patients. MMWR 37:600, 1988 20. Centers for Disease Control: HIV-2 infection-United States. MMWR 38:572, 1989 21. Centers for Disease Control: 1989 sexually transmitted diseases treatment guidelines. MMWR 38(suppI8):1, 1989 22. Centers for Disease Control: Health information for international travel. Atlanta, US Department of Health and Human Services, 1991, p 91 23. Centers for Disease Control: Successful strategies in adult immunization. MMWR 40:700, 1991 24. Clendennen TE, Hames CS, Kees ES, et al: In vitro antibiotic susceptibilities of Neisseria gonorrhoeae isolates in the Philippines. Antimicrob Agents Chemother 36:277, 1992 25. Cole CH, Lacher TG, Bailey Je, et al: Vaginal chemoprophylaxis in the reduction of reinfection in women with gonorrhoea: Clinical evaluation of the effectiveness of a vaginal contraceptive. Br J Vener Dis 56:314, 1980 26. Cortes E, Detels R, Aboulafia D, et al: HIV-l, HIV-2, and HTLV-I infection in high risk groups in Brazil. New Engl J Med 320:953, 1989 27. Cowan ME, Cree GE: A note on the susceptibility of N. gonorrhoeae to contraceptive agent Nonyl-P. Br J Vener Dis 49:65, 1973 28. De Cock KM, Brun-Vezinet F: Epidemiology of HIV-2 infection. AIDS 3(suppl1):S89, 1989 29. De Meis e, De Vasconcellos Ae, Unhares D, et al: HIV-1 infection among prostitutes in Rio de Janeiro, Brazil. AIDS 5:236, 1991 30. Delaporte E, Peeters M, Durand JP, et al: Seroepidemiological surveys of HTLV-I infection among randomized populations of four western central African countries. J AIDS 2:410, 1989 . 31. Donovan B, Harcourt e, Bassett I, et al: Gonorrhoea and Asian prostitution: The Sydney Sexual Health Centre experience. Med J Aust 154:520, 1991

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32. Drugs for sexually transmitted diseases. Med Lett Drugs Ther 33:119, 1991 33. Egglestone SI, Kan KM, Lai CF: Decreased in vitro antibiotic susceptibility of Neisseria gonorrhoeae isolates in Hong Kong. Genitourin Med 66:462, 1990 34. Eyster ME, Alter HI, Aledort LM, et al: Heterosexual cotransmission of hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Ann Intern Med 115:764, 1991 35. Fischl MA, Dickinson GM, Scott GB, et al: Evaluation of heterosexual partners, children, and household contacts of adults with AIDS. JAMA 257:640, 1987 36. Fung HW: Decreased in vitro susceptibility of penicillinase producing Neisseria gonorrhoeae to spectinomycin in Hong Kong. Genitourin Med 65:129, 1989 37. Galli M, Esposito R, Antinori S, et al: HIV-1 infection, tuberculosis, and syphilis in male transsexual prostitutes in Milan, Italy. J AIDS 4:1006, 1991 38. Gentry LO: Clinical experience with temafloxacin. Infections in Med.icine 8(suppl B):21, 1991 39. Grimes DA, Cates W: Family planning and sexually transmitted diseases. In Holmes KK, Mardh PA, Sparling PF, et al (eds): Sexually Transmitted Diseases, ed 2. New York, McGraw Hill, 1990, P 1087 40. Haberberger RL, Fox E, Polycarpe D, et al: Antibiotic susceptibility patterns of Neisseria gonorrhoeae in Djibouti during June 1988. Trans R Soc Trop Med Hyg 84:738, 1990 41. Hayes CG, Manalota CR, Basaca-Sevilla V, et al: Epidemiology of HIV infection among prostitutes in the Philippines. J AIDS 3:913, 1990 42. Hicks DR, Martin LBS, Getchell JP, et al: Inactivation of HTLV-IIl/LAV-infected cultures of normal human lymphocytes by nonoxynol-9 in vitro. Lancet 2:1422, 1985 43. Hira SK, Bhat GJ, Patel JB, et al: Early congenital syphilis: Clinicocardiologic features in 202 patients. Sex Transm Dis 12:177, 1985 44. Hollinger FB: Hepatitis B virus. In Hollinger FB, Robinson WS, Purcell RH, et al (eds): Viral Hepatitis, ed 2. New York, Raven Press, 1991, p 73 45. Hollinger FB: Non-A, non-B hepatitis viruses. In Hollinger FB, Robinson WS, Purcell RH, et al (eds): Viral Hepatitis, ed 2. New York, Raven Press, 1991, p 139 46. Hook EW, Cannon RO, Nahmias AI, et al: Herpes simplex virus infection as a risk factor for human immunodeficiency virus infection in heterosexuals. J Infect Dis 165:251, 1992 47. Houweling H, De Grave A, Smits SP, et al: Risk factors for hepatitis B infection among Dutch expatriates in sub-Saharan Africa. In Proceedings of the Second Conference on International Travel Medicine, Atlanta, 1991, p 88 48. Jephcott AE, Turner A: Ciprofloxacin resistance in gonococci. Lancet 335:165, 1990 49. Jick H, Hannan MT, Stergachis A, et al: Vaginal spermicides and gonorrhea. JAMA 248:1619, 1982 50. Jones ME, Burns SM: A survey of hepatitis C antibody in missionary personnel on UK leave 1983-90. In Proceedings of the Second Conference on International Travel Medicine, Atlanta 1991, p 88 51. Kappus EW, Quinn TC: the spermicide nonoxynol-9 does not inhibit Chlamydia trachomatis in vitro. Sex Transm Dis 13:134, 1986 52. Kelly JP, Reynolds RB, Stagno S, et al: In vitro activity of the spermicide nonoxynol9 against Chlamydia trachomatis. Antimicrob Agents Chemother 27:760, 1985 53. Knight ST, Lee SH, Davis CH, et al: In vitro activity of nonoxynol-9 on McCoy cells infected with Chlamydia trachomatis. Sex Transm Dis 14:165, 1987 54. Kreiss JK, Koech D, Plummer FA, et al: AIDS virus infection in Nairobi prostitutes. N Engl J Med 314:414, 1986 55. Laga M, Plummer FA, Nsanze H, et al: Epidemiology of ophthalmia neonatorum in Kenya. Lancet 2:1145, 1986 56. Laga M: Risk of HIV infection and other STDs for travelers. In Proceedings of the Second Conference on International Travel Medicine, Atlanta 1991, p 36 57. Lange WR, Frame JD: The incidence of viral hepatitis types A and B among American missionaries in Africa. In Proceedings of the Second Conference on International Travel Medicine, Atlanta 1991, p 88 58. Larsen SA, Oberle MW, Sanchez-Braverman JM, et al: A population-based serosurveillance of syphilis in Costa Rica. Sex Transm Dis 18:124, 1991

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59. Le Saux NM, Slaney LA, Plummer FA, et al: In vitro activity of ceftriaxone, cefetamet, ceftetrame, and fleroxacin versus Neisseria gonorrhoeae and Haemophilus ducreyi. Antimicrob Agent Chemother 31:1153, 1987 60. Levine PH, Blattner WA, Clark I, et al: Geographic distribution of HTLV-I and identification of a high risk population. Int J Cancer 42:7, 1988 61. Lind I: Epidemiology of antibiotic resistant Neisseria gonorrhoeae in industrialized and developing countries. Scand J Infect Dis 69(suppl):77, 1990 62. Louv Wc, Austin H, Alexander WI, et al: A clinical trial of nonoxynol-9 for preventing gonococcal and chlamydial infections. J Infect Dis 158:518, 1988 63. Mabey DC, Lloyd-Evans NE, Conteh S, et al: Sexually transmitted diseases among randomly selected attenders at an antenatal clinic in the Gambia. Br J Vener Dis 60:331, 1984 64. Mabey DC: Syphilis in sub-Saharan Africa. Afr J Sex Transm Dis 3:61, 1986 65. Mabey DC, Wall RA, Bello CS: Aetiology of genital ulceration in the Gambia. Genitourin Med 63:312, 1987 66. Mann I, Quinn TC, Piot P, et al: Condom use and HIV infection among prostitutes in Zaire. N Engl J Med 316:345, 1987 67. Mann JM: AIDS-the second decade: A global perspective. J Infect Dis 165:245, 1992 68. Mason PR, Gwnazura L, Latif A, et aI: Antimicrobial susceptibility of Neisseria gonorrhoeae in Harare, Zimbabwe. Sex Transm Dis 17:63, 1990 69. Meheus A: Gonorrhoea as a world health problem. In Bailliere's Clinical Tropical Medicine and Communicable Diseases, vol 2. London, Bailliere Tindall, 1987, p 17 70. Meheus A, Friedman F, Van Dyck E, et al: Genital infections in prenatal and family planning attendants in Swaziland. East Afr Med J 57:212, 1980 71. Meheus A, Widy-Wirski R, D'Costa I, et al: Treatment of gonorrhoea in males in the Central African Republic with spectinomycin and procaine penicillin. Bull WHO 62:89, 1984 72. Minuk GY, Bohme CE, Bowen TJ: Condoms and hepatitis B virus infection. Ann Intern Med 104:584, 1986 73. Nahmias AI, Lee FK, Beckman-Nahmias S: Sero-epidemiological and sociological patterns of herpes simplex virus infection in the world. Scand J Infect Dis 69(suppl):19, 1990 74. Nayyar KC, Stolz E, Michel MF: Rising incidence of chancroid in Rotterdam: Epidemiological, clinical, diagnostic and therapeutic aspects. Br J Vener Dis 55:439, 1979 75. Nielsen NI, Lindhardt BO, Ulrich K: HIV antibodies in Danish Volunteer Service personnel in Kenya, Tanzania and Zambia. Trans R Soc Trop Med Hyg 81:680, 1987 76. Nishimura M, Kumamoto Y, Hirose T, et al: Bacteriologic studies on Neisseria gonorrhoeae isolated in Sapporo, Japan: Investigation of f3-lactamase production and auxotypes. Sex Transm Dis 18:80, 1991 77. Nsanze H, Fast M, D'Costa LI, et al: Genital ulcer in Kenya: A clinical and laboratory study of 100 patients. Br J Vener Dis 57:378, 1981 78. Nsubuga P, Mugerwa R, Nsibambi I, et al: The association of genital ulcer disease and HIV infection at a dermatology-STD clinic in Uganda. J AIDS 3:1002, 1990 79. Nzila N, Laga M, Thiam MA, et al: HIV and other sexually transmitted diseases among female prostitutes in Kinshasa. AIDS 5:715, 1991 80. Nzilambi N, De Cock KM, Forthal DN, et al: The prevalence of infection with human immunodeficiency virus over a lO-year period in rural Zaire. N Engl J Med 318:276, 1988 81. Palomares Jc, Lozano MC, Perea EJ: Antibiotic resistance, plasmid profile, auxotypes and serovars of Neisseria gonorrhoeae strains isolated in Sevilla (Spain). Genitourin Med 66:87, 1990 82. Pandian NA, Shiboski SC, Jewell NP: The effect of number of exposures on the risk of heterosexual HIV transmission. J Infect Dis 161:883, 1990 83. Peeters M, Frost EH, Collet M, et al: Changing antibiotic susceptibility of Neisseria gonorrhoeae in Franceville, Gabon. Antimicrob Agents Chemother 31:1288, 1987 84. Pemberton I, McCann JS, Mahony JD, et al: Socio-medical characteristics of patients attending a VD clinic and the circumstances of infection. Br J Vener Dis 48:39l, 1972 85. Pepin I, Morgan G, Dunn D, et al: HIV-2-induced immunosuppression among

1460

PARENT!

asymptomatic West African prostitutes: Evidence that HIV-2 is pathogenic, but less so than HIV-1. AIDS 5:1165, 1991 86. Piot P, Plummer FA, Rey MA, et al: Retrospective seroepidemiology of AIDS virus infection in Nairobi populations. J Infect Dis 155:1108, 1987 87. Piot P, Holmes KK: Sexually transmitted diseases. In Warren KD, Mahmoud AAF (eds): Tropical and Geographic Medicine, ed 2. New York, McGraw-HilI, 1990, p 894 88. Piot P, Tezzo R: The epidemiology of HIV and other sexually transmitted infections in the developing world. Scand J Infect Dis 69(suppl):89, 1990 89. Plummer FA, Nsanze H, Karasira P, et al: Epidemiology of chancroid and Haerrtophilus ducreyi in Nairobi. Lancet 2:1293, 1983 90. Plummer FA, D'Costa LL Nsanze H, et al: Clinical and microbiologic studies of genital ulcers in Kenyan women. Sex Transm Dis 12:193, 1985 91. Plummer FA, Simonsen IN, Cameron DW, et al: Co factors in male-female sexual transmission of human immunodeficiency virus type 1. J Infect Dis 163:233, 1991 92. Ramachandran S, Ngeow YF: The prevalence of sexually transmitted diseases among prostitutes in Malaysia. Genitourin Med 66:334, 1990 93. Ratnam AV, Chattergee TK, Mulenga RC: Sexually transmitted diseases in pregnant women in Lusaka. Med J Zambia 14:75, 1980 94. Rendon AL, Covarrubias L McCarney KE, et al: A controlled, comparative study of phenylmercuric acetate, nonoxynol-9 and placebo vaginal suppositories as prophylactic agents against gonorrhea. Curr Ther Res 27:780, 1980 95. Ronald AR, Albritton W: Chancroid and Haemophilus ducreyi. In Holmes KK, Mardh PA, Sparling PF, et al (eds): Sexually Transmitted Diseases, ed 2. New York, McGraw Hill, 1990, P 263 96. Rosenberg NL Rojanapithayakorn W, Feldblum PL et al: Effect of contraceptive sponge on chlamydial infection, gonorrhea and candidiasis: A comparative clinical trial. JAMA 257:2308, 1987 97. Ruijs GL Schut IK, Schirm L et al: Prevalence, incidence, and risk of acquiring urogenital gonococcal or chlamydial infection in prostitutes working in brothels. Genitourin Med 64:49, 1988 98. Rwandan HIV Seroprevalence Study Group: Nationwide community-based serological survey of HIV-l and other human retrovirus infections in a central African country. Lancet 1:941, 1989 99. Schroeter AL, Turner RH, Lucas JB, et al: Therapy for incubating syphilis: Effectiveness of gonorrhea treatment. JAMA 218:711, 1971 100. Singh B, Postic B, Cutler JC: Virucidal effect of certain chemical contraceptives on type 2 herpes virus. Am J Obstet Gynecol 126:422, 1976 101. Stamm WE, Holmes KK: Chlamydia trachomatis infections of the adult. In Holmes KK, Mardh PA, Sparling PF, et al (eds): Sexually Transmitted Diseases, ed 2. New York, McGraw Hill, 1990, P 181 102. Stary A, Kopp W, Soltz-Szots J: Medical health care for Viennese prostitutes. Sex Transm Dis 18:159, 1991 103. Stone KM, Grimes DA, Magder LS: Personal protection against sexually transmitted diseases. Am J Obstet Gynecol 155:180, 1986 104. Szmuness W, Harley EL Ikran H, et al: Sociodemographic aspects of the epidemiology of hepatitis B. In Vyas GN, Cohen SN, Schmid R (eds): Viral Hepatitis: A Contemporary Assessment of Etiology, Epidemiology, Pathogenesis and Prevention. Philadelphia, Franklin Institute Press, 1978, p 297 105. Tauris P, Black FT: Heterosexuals importing HIV from Africa. Lancet 1:325, 1987 106. Taylor DN, Duangmani C, Suvongse C, et al: The role of Haemophilus ducreyi in penile ulcerations in Bangkok, Thailand. Sex Transm Dis 11:148, 1984 107. Taylor DN, Pitarangsi C, Echeverria P, et al: Comparative study of ceftriaxone and trimethoprim-sulfamethoxazole for the treatment of chancroid in Thailand. J Infect Dis 152:1002, 1985 108. Tzelpi E, Fragouli E, Athanassopoulou V, et al: Neisseria gonorrhoeae in Athens, Greece: Epidemiologic classification and antimicrobial susceptibility patterns of strains isolated between 1986 and 1989. Sex Transm Dis 18:238, 1991 108a. United States Department of State-Bureau of Consular Affairs: Human immuno-

SEXUALLY TRANSMITTED DISEASES AND TRAVELERS

109. 110. 111. 112. 113. 114.

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deficiency virus (HIV) testing requirements for entry into foreign countries. October, 1991. Vacca K, MacMillan LL: Anogenitallesions in women in Papua New Guinea. Papua New Guinea Med J 23:70, 1980 van Klingeren B, Dessens-Kroon M, Verheuvel M: Increased tetracycline resistance in gonococci in the Netherlands. Lancet 2:1278, 1989 Van de Perre P, Jacobs D, Sprecher-Goldberger S: The latex condom: An efficient barrier against sexual transmission of AIDS-related viruses. AIDS 1:49, 1987 Vazquez F, Palacio V, Vazquez JA, et al: Gonorrhea in women prostitutes: Clinical data and auxotypes, serovars, plasmid contents of PPNG, and susceptibility profiles. Sex Transm Dis 18:5, 1991 Vittecoq D, Roue RT, Mayaud C, et al: Acquired immunodeficiency syndrome after travelling in Africa: An epidemiological study in seventeen caucasian patients. Lancet 1:612, 1987 World Health Organization: Acquired immunodeficiency syndrome (AIDS): Haiti. Weekly Epidemiology Record 66:117, 1991

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Sexually transmitted diseases and travelers.

Sexually active travelers are at risk for a variety of STDs, including traditional venereal infections such as gonorrhea, chlamydial urethritis, syphi...
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