Is the Increase in Notifications of Chlamydia trachomatis Infections in Sweden the Result of Changes in Prevalence, Sampling Frequency or Diagnostic Methods?

Abstract

Based on clinical and laboratory surveillance data, trends in the incidence rates of genital Chlamydia trachomatis infections in Sweden between 1991 and 1999 were analysed according to age group and sex. The influence of changes in laboratory methods on the reported infections was assessed. After a decrease in the incidence rate of infection of 36% between 1991 and 1994, followed by a period of stability, a 20% increase was observed between 1997 and 1999 (from 157 to 189/100,000). Between 1991 and 1999 the female:male ratio decreased from 1.7 to 1.4. Incidence rates started to increase in 1994 in the 15-19 y age group for both sexes. Crude Chlamydia positivity increased from 4.1% (352,050 people tested) in 1994 to 5.4% (305,946 people tested) in 1999. This increase in Chlamydia positivity was seen both in laboratories that had changed to more sensitive methods and in those that had not. Changes in laboratory methods can therefore only partially explain the increase in notified cases. Increased screening of men may have contributed to the increase, but rising incidence rates in all young age groups of both sexes suggest a true increase in prevalence.

Surveillance systems for STIs in the European Union: facing a changing epidemiology

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Nowhere near the point of diminishing returns: correlations between chlamydia testing and notification rates in New South Wales

“…2 In 1999, 39.0% of notified cases in New South Wales were diagnosed using NAATs. By 2001, NAATs had been used to diagnose 71.1% of cases.…”

Infecciones de Transmisión Sexual en Semen: El Hombre como Vector de Transmisión

“…Al ocurrir la inclusión la clamidia se desplaza hacia el aparato de golghi mediante un mecanismo dependiente de dineína y donde el CE comienza a multiplicarse por fisión binaria. Las infecciones causadas por C. trachomatis pueden ocasionar daños graves tales como enfermedades pélvicas inflamatorias (EPI), infertilidad tubárica, embarazo ectópico, dolor abdominal en mujeres y en hombres prostatitis y epididimitis (Gotz et al, 2002). La mayor parte de los estudios in vitro en hombres, buscan esclarecer el efecto que causa la bacteria en el espermatozoide, como se adhiere a él y como se propaga por el aparato reproductor femenino y masculino.…”