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Sexually Transmitted Disease Surveillance 1996

Division of STD Prevention September 1997

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 
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,
1996. U.S. Department of Health and Human Services, Public Health Service.
Atlanta: Centers for Disease Control and Prevention, September 1997.

Copies can be obtained from the Office of Communications, National Center
for HIV, STD, and TB Prevention, Centers for Disease Control and
Prevention, 1600 Clifton Road, Mailstop E-06, Atlanta, Georgia 30333.

The reports for 1993 through 1996 are available electronically on CDC
WONDER. For information about registering for CDC WONDER, please contact
CDC's Epidemiology Program Office at (888) 496-8347. These reports are also
available from the Internet via the CDC home page address
http://wonder.cdc.gov/wonder/data/Reports.html. 


Special Focus Profiles

The Special Focus Profiles section highlights trends and distribution of
sexually transmitted diseases (STDs) in populations of particular interest
for STD and HIV prevention programs in state and local health departments.
These populations are most vulnerable to STDs and their consequences: women
and infants; adolescents and young adults; minorities; and populations in
the southern United States. The Special Focus Profiles refer to figures
located in disease-specific sections in the National Profile. In addition,
there are figures (Figures A-U) that highlight specific points made in the
following text.


STDs in Women and Infants

Public Health Impact

Women and infants disproportionately bear the long term consequences of
STDs. Women infected with Neisseria gonorrhoeae or Chlamydia trachomatis
can develop pelvic inflammatory disease (PID), which, in turn, may lead to
adverse reproductive consequences, e.g., ectopic pregnancy and tubal factor
infertility. If not adequately treated, 20% to 40% of women infected with
chlamydia (1) and 10% to 40% of women infected with gonorrhea (2) develop
PID. Among women with PID, scarring sequelae will cause involuntary
infertility in 20%, ectopic pregnancy in 9%, and chronic pelvic pain in 18%
(3). Approximately 70% of chlamydial infections and 50% of gonococcal
infections in women are asymptomatic (4-6). These infections are detected
primarily through screening programs. The vague symptoms associated with
chlamydial and gonococcal PID cause 85% of women to delay seeking medical
care, thereby increasing the risk of infertility and ectopic pregnancy (7).
Data from a randomized controlled trial of chlamydia screening in a managed
care setting suggest that such screening programs can reduce the incidence
of PID by as much as 60%. (8)

Gonorrhea and chlamydia also result in adverse outcomes of pregnancy,
including neonatal ophthalmia and, in the case of chlamydia, neonatal
pneumonia. Although topical prophylaxis at delivery is effective for
prevention of ophthalmia neonatorum, prevention of neonatal pneumonia
requires antenatal detection and treatment.

Infections with human papillomavirus (HPV) in women are a major concern
because specific HPV subtypes (e.g., types 16, 18, 31, 33, and 35) have
been associated epidemiologically with cervical dysplasia and cervical
cancer. HPV types 6 and 11 in child bearing women can cause laryngeal
papillomatosis in infants.

When a woman has a syphilis infection during pregnancy, she may transmit
the infection to the fetus in utero. This may result in fetal death or an
infant born with physical and mental developmental disabilities. Most cases
of congenital syphilis (CS) are preventable if women are screened for
syphilis and treated early through prenatal care (9).

Observations

--   Between 1995 and 1996, the reported rate of chlamydial infections in
     women increased from 316.2 per 100,000 population to 321.5
     (Figure_6, Table_6). This increase most likely reflects an
     increase in screening rather than an increase in number of cases in
     women; even as reported cases have increased, prevalence among women
     screened in the U.S. has declined (see section on Chlamydia). Despite
     considerable under-reporting, it is important to note that chlamydia
     rates exceed gonorrhea rates in women in many states (Figure_A and
     Figure_B, Table_6 and Table_15).

--   For gonorrhea, the Healthy People year 2000 objective is 100 cases per
     100,000 persons. Gonorrhea rates for women alone exceeded this HP2000
     objective in 22 states (Figure_B, Table_15). The highest rates
     of gonorrhea for women were concentrated in the South.

--   Like chlamydia, gonorrhea is often asymptomatic in women and can only
     be identified through screening. Large-scale screening programs for
     gonorrhea in women began in the late 1970's. After an initial increase
     in cases detected through screening, gonorrhea rates for both women
     and men declined steadily throughout the 1980's and early 1990's
     (Figure_15, Table_15 and Table_16). Gonorrhea rates
     decreased for women from 140.2 cases per 100,000 population in 1995 to
     119.5 in 1996; rates in men also declined from 158.7 to 128.5 from
     1995 to 1996. Men with gonorrhea are usually symptomatic and may seek
     care; therefore, trends in men may be a relatively good indicator of
     trends in incidence of disease. However, trends in women are
     determined more by screening practices, similar to chlamydia.

--   The Healthy People year 2000 objective for primary and secondary
     syphilis is 4.0 per 100,000 persons. Primary and secondary syphilis
     rates for women alone exceeded the HP2000 objective in 15 states and 2
     outlying areas (Figure_C, Table_27). Five southern states
     (Louisianna, Maryland, Mississippi, North Carolina, Tennessee) had
     rates for women that were at least 3 times greater than the HP2000
     objective for primary and secondary syphilis. For congenital syphilis,
     the Healthy People year 2000 objective is 40 per 100,000 live births.
     Five (Arkansas, Maryland, Mississippi, South Carolina, Tennessee) of 8
     states that exceeded the HP2000 objective were in the South
     (Figure_D, Table_38). 

--   The rate of congenital syphilis (CS) closely follows the trend of
     primary and secondary (P&S) syphilis in women (Figure_32). Peaks
     in CS usually occur one year after peaks in P&S syphilis in women. The
     CS rate peaked in 1991 at 107.3 cases per 100,000 live births and has
     declined 72% to 30.4 in 1996 (Figure_33, Table_37). The rate
     of P&S syphilis in women peaked at 17.3 per 100,000 persons in 1990
     and declined 77% to 4.0 in 1996 (Figure_29 and Figure_32,
     Table_27). 

--   Although the 1996 rate of CS was below the Healthy People 2000
     Objective of 40 cases per 100,000 live births, this objective is many
     times greater than the rate of CS of most industrialized countries
     where syphilis and CS have nearly been eliminated (10).

--   Accurate estimates of pelvic inflammatory disease (PID) and tubal
     factor infertility from gonococcal and chlamydial infections are
     difficult to obtain. Definitive diagnosis of these conditions can be
     complex, requiring for example, laparoscopy or laparotomy, while tubal
     patency studies may be needed to accurately document these conditions.
     Most cases of PID are treated on the basis of interpretations of
     clinical findings, which vary between individual practitioners. In
     addition, the settings in which care is provided can vary considerably
     over time. For example, women with PID who would have been
     hospitalized in the 1980's may be treated in out-patient facilities
     during the 1990's. Trends in hospitalized PID have declined steadily
     throughout the 1980's and early 1990's (Figure_F). However, these
     trends may be more reflective of changes in the etiologic spectrum
     (with increasing proportions of more indolent chlamydial infection)
     and clinical management of PID (from in-patient to out-patient) rather
     than true trends in disease (11).

--   Recent evidence suggests that health care practices associated with
     ectopic pregnancy also changed in the late 1980's and early 1990's.
     Before that time, treatment of ectopic pregnancy usually required
     admission to a hospital. Hospitalization statistics were therefore
     useful for monitoring trends in ectopic pregnancy (Figure_E).
     Beginning in 1990, hospitalizations for ectopic pregnancy began to
     decline. Data from out-patient care surveys suggest that nearly half
     of all ectopic pregnancies are treated on an out-patient basis (12).
     The total number of ectopic pregnancies in the U.S. in 1992 was
     estimated to be 108,800 (or 19.7 cases per 1,000 pregnancies), the
     highest level in more than two decades (12).

--   Initial visits to physicians' offices for PID declined from 1993 to
     1995, but increased in 1996 (Figure_G). In 1994, an estimated
     397,000 women aged 15-44 years were diagnosed with PID in emergency
     departments (National Hospital Ambulatory Medical Care Survey, NCHS). 

Figure_A.  Chlamydia -- Rates for women by state: United States and 
               outlying areas, 1996
Figure_B.  Gonorrhea -- Rates for women by state: United States and 
               outlying areas, 1996
Figure_C.  Primary and secondary syphilis -- Rates for women by state: 
               United States and outlying areas, 1996
Figure_D.  Congenital syphilis -- Rates for infants <1 year of age by 
               state: United States and outlying areas, 1996
Figure_E.  Ectopic pregnancy -- Hospitalizations of women 15-44 years 
               of age: United States, 1980-1994
Figure_F.  Pelvic inflammatory disease -- Hospitalizations of women 
               15-44 years of age: United States, 1980-1994
Figure_G.  Pelvic inflammatory disease -- Initial visits to physicians' 
               offices by women 15-44 years of age: United States,
               1980-1996 and Healthy People year 2000 objective


----------
(1)   Stamm WE, Guinan ME, Johnson C. Effect of treatment regimens for
      Neisseria gonorrhoeae on simultaneous infections with Chlamydia
      trachomatis. N Engl J Med 1984;310:545-9.
(2)   Platt R, Rice PA, McCormack WM. Risk of acquiring gonorrhea and
      prevalence of abnormal adnexal findings among women recently exposed
      to gonorrhea. JAMA 1983;250:3205-9.
(3)   Westrom L, Joesoef R, Reynolds G, et al. Pelvic inflammatory disease
      and fertility: a cohort study of 1,844 women with laparoscopically
      verified disease and 657 control women with normal laparoscopy. Sex
      Transm Dis 1992;19:185-92.
(4)   Hook EW III, Handsfield HH. Gonococcal infections in the adult. In:
      Holmes KK, Mardh PA, Sparling PF, et al, eds. Sexually Transmitted
      Diseases, 2nd edition. New York City: McGraw-Hill, Inc, 1990:149-65.
(5)   Stamm WE, Holmes KK. Chlamydia trachomatis infections in the adult.
      In: Holmes KK, Mardh PA, Sparling PF, et al, eds. Sexually
      Transmitted Diseases, 2nd edition. New York City: McGraw-Hill, Inc,
      1990:181-93.
(6)   Zimmerman HL, Potterat JJ, Dukes RL, et al. Epidemiologic differences
      between chlamydia and gonorrhea. Am J Public Health 1990;80:1338-42.
(7)   Hillis SD, Joesoef R, Marchbanks PA, et al. Delayed care of pelvic
      inflammatory disease as a risk factor for impaired fertility. Am J
      Obstet Gynecol 1993;168:1503-9.
(8)   Scholes D, Stergachis A, Heidrich FE, Andrilla H, Holmes KK, Stamm
      WE. Prevention of pelvic inflammatory disease by screening for
      cervical chlamydial infection. N Engl J Med  1996;34(21):1362-66.
(9)   CDC. Guidelines for prevention and control of congenital syphilis.
      MMWR 1988;37(No.S-1).
(10)  Division of STD/HIV Prevention. Healthy People 2000: National Health
      Promotion and Disease Objectives. Progress Review: Sexually
      Transmitted Diseases, October 26, 1994.
(11)  Rolfs RT, Galaid EI, Zaidi AA. Pelvic inflammatory disease: trends in
      hospitalization and office visits, 1979 through 1988. Am J Obstet
      Gynecol 1992;166:983-90.
(12)  CDC. Ectopic pregnancy -- United States, 1990-1992. MMWR
      1995;44:46-8.


STDs in Adolescents and Young Adults

Public Health Impact

Compared to older adults, adolescents (10- to 19-year-olds) and young
adults (20- to 24-year-olds) are at higher risk for acquiring STDs for a
number of reasons: they may be more likely to have multiple (sequential or
concurrent) sexual partners rather than a single, long-term relationship;
they may be more likely to engage in unprotected intercourse; and they may
select partners at higher risk. In addition, for some STDs, e.g., Chlamydia
trachomatis, adolescent women may have a physiologically increased
susceptibility to infection due to increased cervical ectopy and lack of
immunity. During the past two decades, the age of initiation of sexual
activity has steadily decreased and age at first marriage has increased,
resulting in increases in premarital sexual experience among adolescent
women and in an enlarging pool of young women at risk (1,2,3). In addition,
the higher prevalence of STDs among adolescents reflects multiple barriers
to quality STD prevention services, including lack of insurance or other
ability to pay, lack of transportation, discomfort with facilities and
services designed for adults, and concerns about confidentiality.

Observations

--  Numerous prevalence studies in various clinic populations have shown
    that sexually active adolescents have high rates of chlamydial
    infection (4). The Chlamydia Regional Projects that perform large-scale
    screening among women attending family planning clinics demonstrate
    that younger women consistently have higher positivity rates of
    chlamydia than older women, even as prevalence declines. An example is
    the Region X Project, which has screened women since 1988 (5)
    (Figure_H). 

--  Among women, 15- to 19-year-olds had the highest rate of gonorrhea
    (Figure_J, Table_12B), and 20- to 24-year-olds had the highest
    rate of primary and secondary syphilis (Figure_L, Table_24B).
    Among men, 20- to 24-year-olds had the highest rate of gonorrhea and
    second highest rate of primary and secondary syphilis (Figure_K and
    Figure_M, Table_12B and Table_24B).

--  Rates of gonorrhea among male adolescents have steadily decreased
    during the 4 year period 1993-96 (Table_12B). In the 10- to
    14-year-old group, the rate for males decreased from 20.4 per 100,000
    in 1993 to 9.1 in 1996, a decrease of 55%. In the 15- to 19-year-old
    group, the rate declined from 611.4 in 1993 to 394.3 in 1996, a 36%
    decrease. Among young adult men in the 20- to 24-year-old group, the
    rate of gonorrhea fell from 729.9 in 1993 to 522.5 in 1996, a decrease
    of 28%.

--  Rates of gonorrhea among female adolescents also generally decreased
    over the 4 year period 1993-96 (Table_12B). However, both
    adolescent age groups exhibited an increase between 1993 and 1994,
    which was followed by decreases in 1995 and in 1996. This pattern also
    occurred among young adult women. In the 10- to 14-year-old group, the
    rate for females decreased from 78.0 per 100,000 in 1993 to 57.9 in
    1996, a decrease of 26%. In the 15- to 19-year-old group, the rate
    declined from 851.6 in 1993 to 756.8 in 1996, an 11% decrease. Among
    young adult women in the 20- to 24-year-old group, the rate of
    gonorrhea fell from 629.2 in 1993 to 522.9 in 1996, a decrease of 17%.

--  In 1996, the highest age-specific gonorrhea rates among women and the
    second highest rates among men were in the 15- to 19-year-old group
    (Figure_17).

--  From 1995 to 1996, gonorrhea rates increased among American
    Indian/Alaska Native adolescents and young adults (Table_12B).

--  Since 1990, approximately 20,000 female Job Corps entrants have been
    screened each year for chlamydia. The Job Corps, administered by the
    U.S. Department of Labor at 108 sites throughout the country, is a
    residential occupational training program for urban and rural
    disadvantaged youth aged 16-24 years. Among women entering the Job
    Corps in 1996, based on their place of residence just before program
    entry, state-specific chlamydia test positivity ranged from 1.7% to
    17.9% (Figure_I). Chlamydia infection is widespread geographically
    and highly prevalent among these economically disadvantaged young
    women.


Figure_H.   Chlamydia -- Percent positivity among women tested in 
                family planning clinics by age group: Region X, 1988-1996
Figure_I.   Chlamydia -- Percent positivity among 16-24 year-old women 
                entering the U.S. Job Corps by state of residence, 1996
Figure_J.   Gonorrhea -- Age-specific rates among women 10-44 years of 
                age: United States, 1981-1996
Figure_K.   Gonorrhea -- Age-specific rates among men 10-44 years of 
                age: United States, 1981-1996
Figure_L.   Primary and secondary syphilis -- Age-specific rates among 
                women 10-44 years of age: United States, 1981-1996
Figure_M.   Primary and secondary syphilis -- Age-specific rates among 
                men 10-44 years of age: United States, 1981-1996

----------
(1) CDC. Premarital sexual experience among adolescent women -- United
    States, 1970-1988. MMWR 1991;39:929-32.
(2) CDC. Pregnancy, Sexually Transmitted Diseases and Related Risk
    Behaviors Among U.S. Adolescents. Atlanta: Centers for Disease Control
    and Prevention, 1994. Adolescent Health: State of the Nation monograph
    series, No. 2. CDC Publication No. 099-4630.
(3) Forrest JD. Timing of reproductive life stages. Obstet Gynecol
    1993;82(1)105-11.
(4) CDC. Recommendations for the prevention and management of Chlamydia
    trachomatis infections, 1993. MMWR 1993;42(No. RR-12).
(5) Lossick J, Delisle S, Fine D, Mosure D, Lee V, Smith C. Regional
    program for widespread screening for Chlamydia trachomatis in family
    planning clinics. In: Bowie WR, Caldwell HD, Jones RP, et al., eds.
    Chlamydial Infections: Proceedings of the Seventh International
    Symposium of Human Chlamydial Infections, Cambridge, Cambridge,
    University Press, 1990, pp. 575-9.


STDs in Minorities

Public Health Impact

Surveillance data show high rates of STDs for some minority racial or
ethnic groups when compared with rates for whites. Race and ethnicity in
the United States are risk markers that correlate with other more
fundamental determinants of health status such as poverty, access to
quality health care, health care seeking behavior, illicit drug use, and
living in communities with high prevalence of STDs. Acknowledging the
disparity in STD rates by race or ethnicity is one of the first steps in
empowering affected communities to organize and focus on this problem.

Surveillance data are based on cases of STDs reported to state and local
health departments (see Appendix). In many areas, reporting from public
sources (e.g., STD clinics) is more complete than reporting from private
sources. Since minority populations may utilize public clinics more than
whites, differences in rates between minorities and whites may be increased
by this reporting bias.

Observations

--  Although chlamydia is a widely distributed STD among all racial and
    ethnic groups, trends in positivity in women screened in Health and
    Human Services Region X (Alaska, Idaho, Oregon, and Washington) show
    consistently higher rates among minorities (Figure_N).

--  In 1996, African-Americans accounted for about 78% of total reported
    cases of gonorrhea (Table_12A). The overall gonorrhea rates in 1996
    were 825.5 cases per 100,000 for African-Americans and 69.0 for
    Hispanics compared with 25.9 for non-Hispanic whites (Figure_16,
    Table_12B). Compared with 1995, 1996 rates decreased for all
    race/ethnic groups except American Indian/Alaska Native.

--  Gonorrhea rates are very high for African-American adolescents and
    young adults. In 1996, black females aged 15 to 19 years had a
    gonorrhea rate of 3,790.9 cases per 100,000 population. Black men in
    this age group had a gonorrhea rate of 2,357.2. These rates were on
    average about 24 times higher than those of 15- to 19-year-old white
    adolescents (Table_12B). Among 20- to 24-year-olds in 1996, the
    gonorrhea rate among blacks was almost 30 times greater than that of
    whites (3,015.5 vs. 103.9, respectively) (Table_12B).

--  Despite declines in gonorrhea rates for most age and race/ethnic groups
    during the 1980's, African-American adolescents did not show declining
    trends in rates until 1991 (black women) and 1992 (black men). Between
    1995 and 1996 gonorrhea rates for black females aged 15 to 19 years
    declined by 14.1%, and for black males in this age group, by 27.1%
    (Table_12B, Figure_O and Figure_P). 

--  The most recent epidemic of syphilis was largely an epidemic in
    heterosexual, minority populations (1). Since 1990, rates of primary
    and secondary (P&S) syphilis have declined among all racial and ethnic
    groups except American Indian/Alaska Native. However, rates for
    African-Americans and Hispanics continue to be higher than for
    non-Hispanic whites. In 1996, African-Americans accounted for about 84%
    of all reported cases of P&S syphilis (Table_24A). Although the
    rate for African-Americans declined from 44.9 cases per 100,000
    population in 1995 to 30.2 in 1996, the latter rate was nearly 50-fold
    greater than the non-Hispanic white rate of 0.6 per 100,000. Between
    1995 and 1996, primary and secondary syphilis rates for black females
    aged 15 to 19 years declined by 39.8%, and for black males in this age
    group, by 38.7% (Figure_Q and Figure_R, Table_24B). The
    1996 rate of P&S syphilis in Hispanics was 1.9 (Figure_30,
    Table_24B).

--  In 1996, the rate of congenital syphilis in African-Americans was 127.8
    per 100,000 live births and 36.4 in Hispanics compared with 3.2 in
    whites (Figure_S). Compared with 1995, this represented a 37%
    decrease for blacks and a 42% decrease for Hispanics. 

Figure_N.   Chlamydia -- Percent positivity among women tested in 
                family planning clinics by race and ethnicity: Region X,
                1988-1996
Figure_O.   Gonorrhea -- Reported rates for 15-19 year old females by 
                race and ethnicity: United States, 1981-1996
Figure_P.   Gonorrhea -- Reported rates for 15-19 year old males by 
                race and ethnicity: United States, 1981-1996
Figure_Q.   Primary and secondary syphilis -- Reported rates for 15-19 
                year old females by race and ethnicity: United States,
                1981-1996
Figure_R.   Primary and secondary syphilis -- Reported rates for 15-19 
                year old males by race and ethnicity: United States,
                1981-1996
Figure_S.   Congenital syphilis -- Rates for infants <1 year of age by 
                race and ethnicity: United States, 1991-1996


----------
(1) Nakashima AK, Rolfs RT, Flock ML, Kilmarx P, Greenspan JR. Epidemiology
    of syphilis in the United States, 1941 through 1993, Sexually
    Transmitted Diseases 196;23(1):16-23.


STDs in the South

Public Health Impact

The southern region (Alabama, Arkansas, Delaware, District of Columbia,
Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North
Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, West
Virginia) has had higher rates of primary and secondary (P&S) syphilis and
gonorrhea than other regions of the country. The reasons for regional
differences in rates are not well understood, but may include differences
in racial and ethnic distribution of the population, poverty, and
availability and quality of health care services. These racial and ethnic
differentials in STD rates are particularly disturbing in light of the fact
that STDs facilitate HIV transmission at least two to five fold. High HIV
prevalence among childbearing women living in the South may be due, in
part, to the high rates of these other STDs. Data from a randomized
controlled trial of STD treatment to prevent HIV infection suggest that as
much as a 40% reduction in HIV incidence might be achieved in areas with
high STD rates (1).

Observations

--  The South has consistently had higher rates of both gonorrhea and P&S
    syphilis compared with other regions throughout the 1980's and 1990's
    (Figure_12, Figure_13, Figure_25, Figure_27,
    Table_14 and Table_26). In 1996, the South also had the highest
    rate of Chlamydia (Figure_3, Table_5) compared to the other
    regions.

--  In 1996, 6 of the 10 states with the highest chlamydia rates were in
    the South (Table_4). Similarly, the 10 states with the highest
    rates of gonorrhea were all located in the South (Figure_12,
    Table_13). Twelve of 16 states with rates of P&S syphilis above the
    HP2000 objective of 4 per 100,000 persons were located in the South
    (Figure_25 and Figure_26, Table_25). All 8 states with
    rates of P&S syphilis that exceeded 10 cases per 100,000 population (or
    2.5 times the HP2000 national objective) were located in the South
    (Figure_25, Table_25).

--  In 1996, 429 (89%) of 482 counties with P&S syphilis rates above the
    HP2000 objective were located in the South (Figure_26 and
    Figure_T).

--  Of the 429 counties in the South that had a 1996 P&S syphilis rate
    above 4.0 per 100,000 population, 188 (44%) had an increasing rate from
    1995 to 1996 (Figure_T and Figure_U).

Figure_T.   South -- Primary and secondary syphilis case rates by 
                county, 1996
Figure_U.   South -- Increases and decreases in cases of primary and 
                secondary syphilis in 1996 compared with 1995 cases, by
                county

----------
(1) Grosskurth H, Mosha F, Todd J, Mwijarubi E, Klokke A, Senkoro K, Mayaud
    P, Changalucha J, Nicoll A, ka-Gina G, Newell J, Mugeye K, Mabey D,
    Hayes R. Impact of improved treatment of sexually transmitted diseases
    on HIV infection in rural Tanzania: randomised controlled trial. Lancet
    1995;346:530-6.





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