Chlamydia trachomatis infection among Hispanic women in the California-Mexico border area, 1993 : establishing screening criteria in a primary care setting

During January 1-October 15 1993 three clinics in Imperial County California located east of the coastal mountain range which borders Baja California; a large community health center in San Diego County California; and a public health/family planning clinic in Tijuana in Baja California Mexico successfully screened 2378 Hispanic women for Chlamydia trachomatis. The overall chlamydia prevalence was 3.2% (2.1% in Tijuana; 3.3% in California). Chlamydia was more common among the prenatal clients than family planning clients (4.7% vs. 2.6%; p < 0.02). Adolescents had the highest chlamydia infection rate (7.5%). Women born in Mexico or those who visited Mexico for at least one week during the last three months had a similar chlamydia prevalence rate as those born in the US or those who had not visited Mexico recently. The multivariate analysis revealed that significant independent predictors of chlamydia infection included young age (<25 years) (prevalence ratio [PR] = 4.5 for <20 years and 2.5 for 20-24 years) unmarried status (PR = 2) high risk sex behavior (PR = 1.1) exposure to a sexually transmitted disease (PR = 2.6) discharge/bleeding (PR = 1.4) vaginosis (PR = 3.6) and cervicitis (i.e. chlamydia syndrome) (PR = 6). If the clinics had applied the minimum screening criteria recommended by the US Centers for Disease Control less than 50% of the clients would have been screened. Yet it would have identified only 69% of chlamydia infections. If clinics would apply the criteria identified in this survey they would need to screen 64% of their clients which would identify 92% of clients infected with chlamydia. These findings indicate that in the California-Mexico border region chlamydia prevalence among Hispanic women seeking reproductive health care was comparable. They also show that clinics can implement an effective selective screening strategy.