Sexually Transmitted Disease Surveillance 1994

Division of STD Prevention

September 1995

U.S. Department of Health and Human Services
Public Health Service
Centers for Disease Control and Prevention 
National Center for HIV, STD, and TB Prevention (proposed)
Division of STD Prevention
Atlanta, Georgia 30333

                         Copyright Information 

All material contained in this report is in the public domain and may be
used and reprinted without special permission; citation to source, however,
is appreciated.

                           Suggested Citation

Division of STD Prevention. Sexually Transmitted Disease Surveillance,
1994. U.S. Department of Health and Human Services, Public Health Service.
Atlanta: Centers for Disease Control and Prevention, September 1995.

Copies can be obtained from Information Technology and Services Office,
National Center for HIV, STD, and TB Prevention (proposed), Centers for
Disease Control and Prevention, 1600 Clifton Road, Mailstop E-06, Atlanta,
Georgia 30333 or by telephone at (404) 639-1819.

Both the 1993 and 1994 reports are now available electronically on CDC
WONDER. For information about registering for CDC WONDER, please contact
CDC's Information Resource Management Office at (404) 332-4569.

                                Chlamydia

Infections due to Chlamydia trachomatis are among the most prevalent of all
sexually transmitted diseases. In women these infections often result in
serious reproductive tract complications, such as pelvic inflammatory
disease, infertility, and ectopic pregnancy. In addition, infected pregnant
women can infect their babies during delivery. While surveillance of
chlamydial infections is improving, it remains incomplete in many areas of
the country. A combination of factors limit the documentation of the
incidence and prevalence of genital chlamydial infection:  variable
compliance with public health laws and regulations that require health care
providers and laboratories to report cases to local health authorities;
large numbers of asymptomatic persons who can be identified only through
screening; limited resources to support screening activities; and
incompletely developed information management infrastructures for
collecting, maintaining, and analyzing morbidity data. Thus, for most
areas, the number of reported chlamydia cases reported to CDC by state
health departments reflects the degree of local interest in chlamydia as a
public health problem and initial attempts to resolve reporting limitations
rather than true disease burden or trends.

 --  In 1994, 448,984 chlamydial infections were reported to CDC from 47
     states (Table_3). This is the first year that reported cases of
     chlamydia exceeded reported cases of gonorrhea (418,068 gonorrhea
     cases in 1994, Table_1).

 --  From 1984 through 1994 reported rates of chlamydia increased
     dramatically, from 3.2 cases per 100,000 population to 188.4
     (Figure_1). Trends continue to primarily reflect increased
     screening, recognition of asymptomatic infection (mainly in women),
     and improved reporting capacity rather than true trends in disease
     incidence.

 --  As in previous years, rates of chlamydia were highest in the West and
     the Midwest, where substantial resources have been committed for
     organized screening programs (e.g., in family planning clinics)
     (Figure_2 and Figure_3). In the areas where these screening
     programs are in place, chlamydia rates far exceed gonorrhea rates.

 --  Between 1993 and 1994 rates of chlamydia reported from large cities
     (>200,000 population) increased 17% from 280.7 cases per 100,000
     population to 328.4 (Figure_4, Table_6).

 --  Reported rates of chlamydia for women (265.3 per 100,000 population)
     exceed those for men (46.2 per 100,000 population) (Figure_5,
     Table_4, Table_5, Table_7, and Table_8). This is
     mainly due to increased detection of asymptomatic infection in women
     through screening. The low rates in men suggest that many of the sex
     partners of women with chlamydia are not diagnosed or reported. In
     addition, men diagnosed as having non-gonococcal urethritis are
     treated but frequently not tested. A large proportion of these men are
     infected with chlamydia, but they are not detected by surveillance
     systems based on laboratory reporting of positive chlamydia tests.

 --  Additional information on chlamydia screening programs in women and
     chlamydia in adolescents and minority populations can be found in the
     Special Focus Profiles section.


Figure_1. Chlamydia - Reported rates: United States, 1984-1994    
Figure_2. Chlamydia - Rates by state: United States, 1994    
Figure_3. Chlamydia - Rates by region: United States, 1984-1994    
Figure_4. Chlamydia - Rates in U.S. cities of >200,000 population,
              1984-1994
Figure_5. Chlamydia - Rates by gender: United States, 1984-1994    

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