Killewo J Z, Sandström A, Bredberg Råden U, Mhalu F S, Biberfeld G, Wall S
Department of Epidemiology and Biostatistics, Muhimbili University College of Health Sciences, Dar es Salaam, Tanzania.
Int J STD AIDS. 1994 Nov-Dec;5(6):424-31. doi: 10.1177/095646249400500609.
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.
1987年，坦桑尼亚卡盖拉地区启动了基于人群的HIV-1感染患病率和发病率研究。为了制定更好的性传播疾病控制策略，对梅毒螺旋体感染的患病率和发病率进行了研究。仅通过对梅毒螺旋体血细胞凝集试验（TPHA）呈血清阳性来诊断既往或已治疗的梅毒螺旋体感染，而通过对性病研究实验室试验（VDRL）和TPHA试验均呈血清阳性来诊断活动性梅毒。1989年，通过在1987年最初血清学阴性的研究人群的随访期间发现TPHA血清学阳性个体来测量血清转化。该地区成年总样本中活动性梅毒的总体患病率为5.9%，而既往梅毒的患病率为13.5%。发现HIV-1感染患病率与两种梅毒之间的关联非常显著。然而，一种既往感染与另一种感染的血清转化之间存在关联，但无统计学意义。基于该地区成年人群队列中的血清转化情况，梅毒的总体发病率为每1000人年11.6例。鉴于这些发现，梅毒是该地区一个严重的健康问题，传播率很高，应努力加以控制。干预研究应利用这些基线数据，并监测梅毒发病率的变化，这些变化可能表明性行为的改变。这些指标也有助于评估旨在减少该地区HIV、梅毒和其他性传播疾病传播的干预措施的影响。
