Prevalence and Incidence of Syphilis and its Association with HIV-1 Infection in a Population-Based Study in the Kagera Region of Tanzania

Abstract

Population-based prevalence and incidence studies on HIV-1 infection were started in the Kagera region of Tanzania in 1987. The prevalence and incidence of infection with Treponema pallidum was studied to enable development of better strategies for STD control.

Serological diagnosis of a past or treated infection with Troponema pallidum was made by seropositivity only to TPHA testing while active syphilis was diagnosed by seropositivity to both VDRL and TPHA tests. Seroconversion was measured in 1989 by finding TPHA serologically positive individuals during the follow-up period among the initially seronegative study population of 1987.

The overall prevalence of active syphilis in the total sample of adults in the region was found to be 5.9% while that of past syphilis was 13.5%. The association between the prevalence of HIV-1 infection and syphilis of both types was found to be highly significant. However, the association between one pre-existing infection and seroconversion in the other was present but not statistically significant. The overall incidence of syphilis based on seroconversion in a cohort of adults in the region was found to be 11.6 per 1000 person-years at risk.

In view of these findings, syphilis is a significant health problem in the region with a high level of transmission and efforts should be made to control it. Intervention studies should use these base-line data and monitor changes in syphilis incidence which may indicate changes in sexual behaviour. Such indicators could also be useful for evaluating the impact of interventions directed at reducing the transmission of HIV, syphilis and other STDs in the region.

Keywords

Syphilis Treponema pallidum treponemal disease seroconversion sexually transmitted diseases prevalence incidence epidemiology Kagera region Tanzania Africa

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References

Laurie

A pilot scheme of venereal disease control in East Africa. Br J Vener Dis 1958;34:16–21.

Larsson

Conversion to greater freedom: Women, church and social change in North Western Tanzania under colonial rule. Doctoral dissertation at Uppsala University; 1991: pp 96. Acta Universitatis Upsaliensis, Studia Historica Upsaliensia 162.

Cooper-Poole

Prevalence of syphilis in Mbeya, Tanzania; The validity of the VDRL as a screening test. E Afr Med J 1986;63(10):646–50.

Ismail

Ahmed

Jama

Syphilis, gonorrhoea and genital chlamidial infection in a Somali village. Genitourin Med 1990;66:70–5.

Ratnam

Din

Hira

Syphilis in pregnant women in Zambia. Br J Vener Dis 1982;58:355.

Liljestrand

Bergstrom

Nieuwenhuis

Hederstedt

Syphilis in pregnant women in Mozambique. Genitourin Med 1985;61:355–8.

Nzila

Laga

Thiam

Mayimona

HIV and other sexually transmitted diseases among female prostitutes in Kinshasa. AIDS 1991;5:715–21.

Hudson

Hennis

AJM

Kataaha

Risk factors for the spread of AIDS in rural Africa; Evidence from a comparative seroepidemiological survey of AIDS, hepatitis B and syphilis in Southwestern Uganda. AIDS 1988;2:255–60.

Damiba

Vermund

Kelley

KF.

Prevalence of gonorrhoea, syphilis and trichomoniasis in prostitutes in Burkina Faso. East Afr Med J 1990;67:473–7.

10.

Gini

Chukudebelu

Njoku-Obi

Antenatal screening for syphilis at the University of Nigeria Teaching Hospital, Enugu, Nigeria. Int J Gynaecol Obstet 1989;29:321–4.

11.

Jama

Hederstedt

Osman

Syphilis in women of reproductive age in Mogadishu, Somalia: Serological Survey. Genitourin Med 1987;63:326–8.

12.

Ahmed

Omar

Adan

Guled

Grillner

Bygdeman

Syphilis and human immunodeficiency virus seroconversion during a 6-month follow-up of female prostitutes in Mogadishu, Somalia. Int J STD AIDS 1991;2:119–23.

13.

D'Costa

Plummer

Bowmer

Prostitutes are a major reservoir of sexually transmitted diseases in Nairobi, Kenya. Sex Transm Dis 1985;12(3):64–7.

14.

de Lalla

Rizzardini

Rinaldi

Santoro

Zeli

Verga

HIV, HBV, delta agent and Treponema pallidum infections in two rural African areas. Trans R Soc Trop Med 1990;84:144–7.

15.

Robertson

Spector

Syphilis serology among women attending an antenatal clinic. S Afr J Sex Transm Dis 1985;5:18–21.

16.

Naicker

Moodley

Van Middlekoop

Cooper

, Serological diagnosis of syphilis in pregnancy. S Afr Med J 1983;63:536–7.

17.

Fehler

Duncan

Bilgeri

Ballard

RC.

Sexually transmitted diseases amongst urban black women. S Afr J Sex Transm Dis 1984;4:48–53.

18.

Ursi

van Dyck

van Houtte

Syphilis in Swaziland: A serological survey. Br J Vener Dis 1981;57:95–9.

19.

Venegas

Human immunodeficiency virus infection and syphilis in Honduran female prostitutes. Int J STD AIDS 1991;2:110–13.

20.

Smikle

James

OB'L

Prabhakar

Biological false positive serological tests for syphilis in the Jamaican population

Genitourin Med 1990;66:76–8.

21.

Leonard

Sacks

Franks

Sikes

RK.

Prevalence of human immunodeficiency virus, hepatitis B, and syphilis among female prostitutes in Atlanta. J Med Assoc Georgia 1988;77:162–4.

22.

Larsen

Oberle

Sanchez-Braverman

A population-based serosurveillance of syphilis in Costa Rica. Sex Transm Dis 1991;18(2):124–8.

23.

Mhalu

FS.

Inter-relationships between HIV infection and other sexually transmitted diseases. E Afr Med J 1990;67(7):512–17.

24.

Kreiss

Koech

Plummer

AIDS virus infection in Nairobi prostitutes: Spread of the epidemic to East Africa. N Engl J Med 1986;314:414–18.

25.

Evans

Dawson

McLean

Sexual lifestyle and clinical findings related to HTLV-III/LAV status in homosexual men. Genitourin Med 1986;62:384–9.

26.

The Collaborative Study Group of AIDS in Haitian Americans: Risk factors for AIDS among Haitians residing in the United States: Evidence of heterosexual transmission. JAMA 1987;257:635–9.

27.

Pallangyo

Swai

Omari

Prospective study of prevalence and incidence of HIV infection and other STDs in Hotel workers in Dar es Salaam. Paper presented at the International Conference on AIDS and STDs in Africa in Cameroon, Yoaunde 8–11 December, 1992. Abstract No. TO 022.

28.

Centers for Disease Control. MMWR 1987;36:393.

29.

Brown

Syphilis and other venereal diseases. Cambridge Mass: Harvard University Press, 1970.

30.

Ministry of Health, United Republic of Tanzania. Annual report of the National AIDS Control Programme and AIDS Surveillance. Report no. 4, March, 1991.

31.

Mertens

Hayes

Smith

PG.

Epidemiological methods to study the interaction between HIV infection and other sexually transmitted diseases. AIDS 1990;4:57–65.

32.

Killewo

JZJ

Nyamuryekunge

Sandstrom

Prevalence of HIV-1 infection in the Kagera region of Tanzania: A population based study. AIDS 1990;4:1081–5.

33.

Anonymous. Manual of tests for health, education and welfare. Public Health Service Publication No 411. Washington, DC: US Government Printing Office.

34.

Tomizawa

Kasamatsu

Haemagglutination tests for the diagnosis of syphilis. Jpn J Med Sci 1966;19:305–8.

35.

Killewo

JZJ

Sandstrom

Raden

U Bredberg

Mhalu

Biberfeld

Wall

The incidence of HIV-1 infection among adults in the Kagera Region of Tanzania. Int J Epidemiol 1993;22(3):528–36.

36.

Poulsen

Ullman

AIDS induced decline of incidence of syphilis in Denmark. Acta Dermato-Vener (Stockholm) 1985;51:567–9.

37.

Anonymous. Continuing increase in infectious syphilis—United States. MMWR 1988;37:35–8.

38.

Anonymous. Syphilis and congenital syphilis—United States. MMWR 1988;37:486–9.