Sexually Transmitted Disease Morbidity:
Selected STDs by Age, Gender, and Race/Ethnicity
United States and Puerto Rico
1996 - 2014

Summary:    This dataset contains Sexually Transmitted Disease (STD) morbidity case reports reported to the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention (NCHHSTP), Centers for Disease Control and Prevention (CDC). The number of cases and disease incidence rates are reported by year, gender of patient, age group, race/ethnicity, type of STD, and area of report.

Population:    Disease reports are from the 50 United States, the District of Columbia and Puerto Rico. See Data Source Information for more about the denominator population data sources.

Source:    Centers for Disease Control and Prevention, Sexually Transmitted Disease Surveillance. The latest CDC STD published surveillance reports are available at STD Surveillance and Statistics.

In WONDER:    You can produce tables, maps, charts, and data extracts. Obtain incidence counts and rates, and select specific disease and demographic criteria to produce cross-tabulated incidence measures. You can limit and index your data by any and all of the variables.

Please refer to the following topics:

STD Morbidity Data Request
Data Source Information
Additional Information

STD Morbidity Data Request



Output:    You can produce tables, maps, charts, and data extracts.

Variables:    You can limit and index your data by any and all of these variables:
  1. Disease: Chlamydia, Gonorrhea, Primary and Secondary Syphilis (combined)
  2. Age groups: 0-14 years, 15-19 years, 20-24 years, 25-29 years, 30-34 years, 35-39 years, 40+ years
  3. Gender: Female, Male, Unknown
  4. Race/Ethnicity: American Indian or Alaskan Native, Asian or Pacific Islander, Black or African American, Hispanic, White, Unknown
  5. Regional multi-state groups:
    STD reporting regions
    MMWR reporting regions
    HHS regions
  6. State including the District of Columbia and Puerto Rico.
  7. Year: 1996-2014


How?    The Request screen has sections to guide you through the making a data request as step-by-step process. However, to get your first taste of how the system works, you might want to simply press any Send button, and execute the default data request. The data results for your query appear on the Table screen. After you get your data results, try the Chart and Map screens. Or export your data to a file (tab-delimited line listing) for download to your computer.

For more information, see the following:
Quick Start Guide
Step 1, Organize and label results
Step 2, Select location
Step 3, Select disease, age, race/ethnicity, gender and year
Step 4, Other options

'By-Variables'    Select variables that serve as keys (indexes) for organizing your data. See How do I organize my data? for more information.
Note:    To map your data, you must select at least one geographical location as a "By-Variable" for grouping your data, such as State.

Help:    Click on any button labeled "Help", located to the right hand side of the screen at the top of each section. Or click on any label, such as the "Group Results By" label.

Send:    Sends your data request to be processed on the CDC WONDER databases. The Send buttons are located on the bottom of the Request page, and also in the upper right corner of each section, for easy access.


Step 1. Organize table layout:

Group Results By:    Select up to five variables that serve as keys for grouping your data. See Group Results By below for hints.
Title:    Enter any desired description to display as a title with your results.

The following statistical measures are available as query results:

  1. Counts
  2. Rates

Group Results By...

Select up to five variables that serve as keys for grouping your data. For example, you could select to group (summarize, stratify, index) your data by State and by Year, to compare each the disease reports by state for each year.

How?   

Hints:   

  1. About charts:
    You cannot make charts when your data has more than two By-Variables.
  2. About maps:
    To make a map, you must request data grouped by a geographic location variable, such as State, as the first By-Variable. Then click the Map tab after you obtain the data results.
  3. About regions:
    You can only select one type of regional area division for a data request. For example, if you select to group the data by HHS regions , then you cannot also group the data by MMWR regions in the same request. However, you can also group the data by State .
  4. When data are grouped by Region (when Region is selected as a By-Variable) then the data includes US and Puerto Rico.
Counts

Counts show the sum or the frequency incidence of STD disease case reports, for the selected categories in the data request.

Rates

The rates are calculated as the incidence of STD disease reports, divided by the population, and then the result is multiplied by 100,000 to indicate the rate per so many persons.

Hints:  
  • You must group data by Disease to show rates when more than 1 disease is selected.
  • You must group by Location to calculate rates if your data selection includes Puerto Rico.
  • You can select the factor for rates in the Other options section on the data request screen. The default factor is per 100,000 persons.

Notes:  

  • To see Rate and Population for more than one disease, you must also group by Disease. Rates are not reported when data are combined for disease categories, because the reporting populations vary for different diseases. For example, the denominator population for Chlamydia in years 1996 -1999 excludes part of New York state. See Reporting Issues for more information.
  • If the selected locations include Puerto Rico, then rates are not available unless data are grouped by location. Rates are not calculated for Puerto Rico because population denominator data by the race/ethnicity groups in this data set are not available at the time of publication.
  • The phrase Not Applicable is shown when the denominator population is not on record, or when the rate cannot be calculated due to lack of disease incidence count or lack of denominator population. Population data are not available for Puerto Rico, nor for persons of unknown age, race/ethnicity or gender.
  • See About Rates in the Additional Information section below.
Step 2. Select location:
Click a button to choose locations for States and outlying areas or Regions. You can limit to your data request to items in only one of these categories. However, you can group the data report by another location type, to show a row for each area.
  1. State and outlying areas
  2. MMWR reporting regions
  3. HHS regions
  4. STD reporting regions
How?

Note:
Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.

States and Outlying Areas

Select the location(s) that represent the patient's home state. Any number of locations can be specified here.

How?

Notes:

  1. The selection "United States, D.C. and outlying areas" includes Puerto Rico. Data by age, race/ethnicity and gender are not currently available for Guam and the Virgin Islands.
  2. Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.
  3. When the data are exported, separate columns show both the label and the code for each value. To see the full list of states and code values, request data grouped by State for the "United States, D.C. and outlying areas," and export the data results.

MMWR Regions

The states are grouped into reporting regions for the Morbidity and Mortality Weekly Report (MMWR). Select the location(s) that represent the patient's home state. Any number of locations can be specified here.

How?

Notes:

  1. Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.
  2. When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by this region for the "United States, D.C. and outlying areas," and export the data results.
Morbidity and Mortality Weekly Report (MMWR) Regions List of States
  1  New England Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont
  2  Middle Atlantic New Jersey, New York, Pennsylvania
  3  East North Central Illinois, Indiana, Michigan, Ohio, Wisconsin
  4  West North Central Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota
  5  South Atlantic Delaware, District of Columbia (DC), Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, West Virginia
  6  East South Central Alabama, Kentucky, Mississippi, Tennessee
  7  West South Central Arkansas, Louisiana, Oklahoma, Texas
  8  Mountain Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming
  9  Pacific Alaska, California, Hawaii, Oregon, Washington
 10  Territories Guam, Puerto Rico, Virgin Islands

HHS Regions

The states are grouped into reporting regions for the federal department of Health and Human Services (HHS). Select the location(s) that represent the patient's home state. Any number of locations can be specified here.

How?

Notes:

  1. Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.
  2. When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by this region for the "United States, D.C. and outlying areas," and export the data results.

Health and Human Services (HHS) Regions List of States
  1 Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, Vermont
  2 New Jersey, New York, Puerto Rico (data are not available for the Virgin Islands)
  3 Delaware, District of Columbia, Maryland, Pennsylvania, Virginia, West Virginia
  4 Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee
  5 Illinois, Indiana, Michigan, Minnesota, Ohio, Wisconsin
  6 Arkansas, Louisiana, New Mexico, Oklahoma, Texas
  7 Iowa, Kansas, Missouri, Nebraska
  8 Colorado, Montana, North Dakota, South Dakota, Utah, Wyoming
  9 Arizona, California, Hawaii, Nevada (data are not available for American Samoa and Guam)
10 Alaska, Idaho, Oregon, Washington

STD Regions

The states are grouped into reporting regions for the Sexually Transmitted Disease (STD) surveillance program. Select the location(s) that represent the patient's home state. Any number of locations can be specified here.

How?

Notes:

  1. Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.
  2. When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by this region for the "United States, D.C. and outlying areas," and export the data results.

STD Regions List of States
  1.  West Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming
  2.  Midwest Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin
  3.  Northeast Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont
  4.  South Alabama, Arkansas, Delaware, District of Columbia (DC), Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, West Virginia
  5.  Territories   Guam, Puerto Rico, Virgin Islands
Step 3. Select disease, age, race/ethnicity, gender, and years:
Limit your data request to the any number of options. The default option is all values.
  1. Disease and disease groups: Chlamydia, Gonorrhea, and Primary and Secondary Syphilis (combined)
  2. Year: 1996 - 2014
  3. Gender: Female, Male, Unknown
  4. Age group: 0-14, 15-19, 20-24, 25-29, 30-34, 35-39, 40+
  5. Race/Ethnicity: American Indian or Alaskan Native, Asian or Pacific Islander, Black or African American, Hispanic, White, Unknown
How?
See "How do I select items from the list box?" for help selecting items in a list box.

Note:
The reporting rules for the diseases vary. Each state is a unique jurisdiction with different reporting rules. Reporting rules also change over time. See Reporting Issues for more information.

Disease

Select one or more diseases to limit your data request.

How?
See "How do I select items from the list box?" for help selecting items in a list box.

Notes:

  1. Each state is a unique jurisdiction with different reporting rules for each disease. Reporting rules vary each year. See Reporting Issues for more information.
  2. When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by disease for "All Diseases" and export the data results.
Disease Code Description
274 Chlamydia
280 Gonorrhea
310 Primary and Secondary Syphilis

Year

Select any number of years to limit your data requests to the selected values. This field contains the year the case was reported.

How?
See "How do I select items from the list box?" for help selecting items in a list box.

Note:
The years of available case reports are 1996 to 2014.

Gender

Select one or more values from the list to limit your data request to the selected values. Gender is categorized as Female, Male or Unknown.

How?
See "How do I select items from the list box?" for help selecting items in a list box.

Notes:

  • Rates are not available for the specific category for persons of unknown gender, because denominator populations are not available for this category.
  • Gender-specific rates for a given area may be under-estimated when there are a high proportion of cases with unknown gender reported from that area.
  • When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by Gender for "All Genders," and export the data results.

Age Groups

Select any number of years to limit your data requests to the selected values. Select one or more values from the list to limit your data request to the selected values. Age is aggregated into the following groups: 0-14 years, 15-19, 20-24, 25-29, 30-34, 35-39, 40+, Unknown. Cases with Unknown age are included in the 1996-2014 data and the archive data. The Unknown age group is not included in the 1996-2009 data.

How?
See "How do I select items from the list box?" for help selecting items in a list box.

Notes:

  • The "All ages" category includes cases for all ages and cases with Unknown age. For the 1996-2009 and 1996-2008 archive data, cases for persons under age 15 are excluded, and the population denominator data for persons under age 15 are likewise omitted. Thus the total number of cases and the total rates produced by the archive data may differ from other reports that include all ages.
  • Rates are not available for the specific category for persons of unknown age, because denominator populations are not available for this category.
  • Age-specific rates for a given area may be under-estimated when there are a high proportion of cases with unknown age reported from that area.
  • When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by Gender for "All" age groups, and export the data results.

Race/Ethnicity

Select one or more values from the list to limit your data request to the selected values. Race is categorized as American Indian or Alaskan Native, Asian or Pacific Islander, Black or African American, Hispanic, White, and Unknown.

How?
See "How do I select items from the list box?" for help selecting items in a list box.

Notes:

  • Rates are not available for the specific category for persons of unknown race/ethnicity, because denominator populations are not available for this category.
  • Race/ethnicity-specific rates for a given area may be under-estimated when there are a high proportion of cases with unknown race/ethnicity reported from that area.
  • When the data are exported, separate columns show both the label and the code for each value. To see the full list of labels and code values, request data grouped by Race/Ethnicity for "All" race groups, and export the data results.

Step 4. Other Options:

Export Results:    If checked, then query results are exported to a local file. More information on how to import this file into other applications can be found here.

Show Totals:   If checked totals and sub-totals will appear in the results table. However, totals are not shown for STD Morbidity when data are grouped by Disease, because the populations shown are disease-specific. See Reporting Issues for more information.

Show Zero Values:    If checked, rows containing zero counts display in the results table. If unchecked, rows with zero cases are hidden.

Show Suppressed Values:    If checked, rows containing suppressed counts display in the results table. If unchecked, rows with suppressed figures are hidden. For more information, see Assurance of Confidentiality.

Precision:    Select the precision for rate calculations. When the rate calculated for a small numerator (incidence count) is zero, you may increase the precision to reveal the rate by showing more numbers to the right of the decimal point.

Data Access Timeout:    This value specifies the maximum time to wait for the data access for a query to complete. If the data access takes too long to complete, a message will be displayed and you can increase the timeout or simplify your request. If you can't complete a request using the maximum timeout, contact user support and we will try to run a custom data request for you.

Calculate Rates Per:    This value is the factor for the rate calculation. The default value is per 100,000 persons.

Data Source Information

Disease Incidence Sources:    The data are based on case reports of sexually transmitted diseases submitted by state and local health departments to CDC's Division of STD/HIV Prevention. The data are reported through STD*MIS, the National Electronic Telecommunications System for Surveillance (NETSS) or the National Electronic Disease Surveillance System (NEDSS).

To learn more about the methods and source of these data please refer to:

Current Selected STDs by Age, Race/Ethnicity, and Gender for years 1996-2014:   Reports and corrections sent to CDC on hardcopy forms and for NETSS electronic data through June 10, 2015 have been included in the data for years 1996 - 2014. Note that the data include case reports for persons of unknown age. See also Sexually Transmitted Disease Surveillance 2014.

Archive Selected STDs by Age, Race/Ethnicity, and Gender for years 1996-2013:   Reports and corrections sent to CDC on hardcopy forms and for NETSS electronic data through June 4, 2014 have been included in the data for years 1996 - 2013. Note that the data include case reports for persons of unknown age. See also Sexually Transmitted Disease Surveillance 2013.

Archive Selected STDs by Age, Race/Ethnicity, and Gender for years 1996-2009:   Reports and corrections sent to CDC on hardcopy forms and for NETSS electronic data through June 9, 2010 have been included in the data for years 1996 - 2009. Note that the data do not include case reports for persons of unknown age. See also Sexually Transmitted Disease Surveillance 2009.

Archive Selected STDs by Age, Race/Ethnicity, and Gender for years 1996-2008:   Reports and corrections sent to CDC on hardcopy forms and for NETSS electronic data through June 10, 2009 have been included in the data for years 1996 - 2008. Note that the data include case reports for persons of unknown age. See also Sexually Transmitted Disease Surveillance 2008.



Population Data Sources:   

Due to use of the updated population data, rates may be different from prior or archive data sets.

  • United States state and national population:
    • Data for years 2011-2014: 
      The population data used to calculate rates are the National Center for Health Statistics July 1st bridged-race postcensal population estimates for the resident population based on the Census 2010 counts. The population estimates were prepared under a collaborative arrangement with the U.S. Census Bureau and the National Center for Health Statistics. The population estimates are available on the Internet from: http://www.cdc.gov/nchs/nvss/bridged_race.htm. See population details below for more information.
    • Data for year 2010: 
      The national population shown as the denominator for rate calculations is the sum of the state populations for each state reporting diseases in the given year. The population data used to calculate rates are the National Center for Health Statistics April 1st, 2010 bridged-race population estimates for the resident population based on the Census 2000 counts. The population estimates were prepared under a collaborative arrangement with the U.S. Census Bureau and the National Center for Health Statistics. The population estimates are available on the Internet from: http://www.cdc.gov/nchs/nvss/bridged_race.htm. See population details below for more information.
    • Data for years 2000-2009: 
      The national population shown as the denominator for rate calculations is the sum of the state populations for each state reporting diseases in the given year. The population data used to calculate rates are the National Center for Health Statistics July 1st bridged-race postcensal population estimates for the resident population based on the Census 2000 counts. The population estimates were prepared under a collaborative arrangement with the U.S. Census Bureau and the National Center for Health Statistics. The population estimates are available on the Internet from: http://www.cdc.gov/nchs/nvss/bridged_race.htm. See population details below for more information.
    • Data for years 1996-1999: 
      The population counts for 1990-1999 incorporated the bridged single-race estimates of the April 1, 2000 resident population census. These files were prepared by the U.S. Census Bureau with support from the National Cancer Institute. The July 1st intercensal population estimates are available on the Internet from: http://www.cdc.gov/nchs/nvss/bridged_race.htm.
  • Outlying areas: 
    • Annual population estimates for Puerto Rico are not available by age/race/sex at the time of publication.
Population details:

The 1996-2014 data by age, race/ethnicity and sex includes these sources of population data:

  • The 2013 and 2014 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2010 - July 1, 2013, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2013). Released June 26, 2014.
  • 2012 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2010 - July 1, 2012, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2012). Released June 13, 2013.
  • 2011 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2010 - July 1, 2011, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2011). Released July 18, 2012.
  • 2010 state population estimates are from the National Center for Health Statistics: Bridged-race estimates of the resident population of the United States for April 1st, 2010, by year, county, age, bridged race, Hispanic origin, and sex Released November 17, 2011.
  • 2009 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000 - July 1, 2008, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2009). Released July 23, 2010.
  • 2008 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000 - July 1, 2008, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2008). Released September 2, 2009.
  • 2007 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000 - July 1, 2006, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2007). Released September 5, 2008.
  • 2006 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000 - July 1, 2006, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2006). Released August 16, 2007.
  • 2005 state population estimates from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000-July 1, 2005, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2005). Released August 16, 2006.
  • 2004 state population estimates from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000-July 1, 2004, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2004). Released September 8, 2005.
  • 2003 state population estimates from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000-July 1, 2003, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2003). Released September 14, 2004.
  • 2000, 2001, 2002 state population estimates from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000-July 1, 2002, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2002). Released August 1, 2003.
  • 1996-1999 state population estimates from the National Center for Health Statistics: intercensal estimates of the resident population of the United States for July 1, 1990-July 1, 1999, by year, county, age, bridged race, Hispanic origin, and sex. Released April 15, 2003. Prepared by the U.S. Census Bureau with support from the National Cancer Institute.

Differences between the current population sources and the archive data collection:

  • In the 1996-2013 archive data, because 2013 population estimates were not available at the time of publication, the 2012 and 2013 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2010 - July 1, 2012, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2012). Released June 13, 2013.
  • In the 1996-2011 archive data, because 2011 population estimates were not available at the time of publication, the 2011 population estimates are from the 2010 state population estimates are from the National Center for Health Statistics: Bridged-race estimates of the resident population of the United States for April 1st, 2010, by year, county, age, bridged race, Hispanic origin, and sex Released November 17, 2011.
  • In the 1996-2009 archive data, the population sources for each available data year are described above.
  • In the 1996-2008 archive data, because 2008 population estimates were not available at the time of publication, the 2008 and 2007 state population estimates are from the National Center for Health Statistics: Postcensal estimates of the resident population of the United States for July 1, 2000 - July 1, 2006, by year, county, age, bridged race, Hispanic origin, and sex (Vintage 2007). Released September 5, 2008.



Additional Information

Suggested Citation for the Current Release:    US Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for HIV, STD and TB Prevention (NCHSTP), Division of STD/HIV Prevention, Sexually Transmitted Disease Morbidity 1996 - 2014, by gender, age group and race/ethnicity, CDC WONDER Online Database.

Contact:    Please call toll-free 1-800-CDC-INFO (800-232-4636) or e-mail the Division of Sexually Transmitted Diseases Prevention at sdmb@cdc.gov.

About Rates:    Notes regarding rate calculations:
  • The default rate shown is the rate per 100,000 persons. The rate is calculated as the disease incidence count reported, divided by the population, and then the result is multiplied by 100,000 (or the specified factor in the data request criteria).
  • The phrase Not Applicable is shown when the denominator population is not on record, or when the rate cannot be calculated due to lack of disease incidence count or lack of denominator population. Population denominator data are not available for persons of unknown age, gender or race/ethnicity, nor available for Puerto Rico at the time of publication.
  • For the 1996-2008 and 1996-2009 archive data, rates are not comparable to statistics calculated for all ages, because the case data and population data in the archive data exclude persons under the age of 15.
  • Due to the use of updated population data, rates may be different from previously published reports or archive data sets.
  • Unknown and missing values for age, race/ethnicity and sex are not redistributed in this data collection, thus the age, race/ethnicity or gender specific rates are not comparable to rates calculated where unknown and missing values are redistributed.
  • Cases with unknown age values are not included in the 1996-2009 data, however these cases are included in the 1006-2008 data archive. This change affects total counts and rates when comparing figures.
  • Rates are reported when data are grouped by disease or when data for a single disease is shown. Populations vary per disease, reporting jurisdiction and year. See Reporting Issues for more information.
  • The denominator population used to compute the overall U.S. rate varies from year to year . The overall U.S. rate is calculated from the sum of the state cases and populations. Denominator populations vary per disease and per state due to reporting differences. See Reporting Issues for more information.
  • Impact of reported cases with missing demographic data on STD rates:  when reviewing STD rate data by demographic subgroup, e.g., by age group, gender, or race/ethnicity, note the number and percentage of reported STD cases that have unknown data for the subgroup of interest. Rates by age group, gender, or race/ethnicity are calculated using only cases with known information in the numerator divided by the comparable U.S. Census population by year and subgroup. When information is unknown, the cases do not contribute to the numerator and therefore subgroup-specific rates are underestimates of the actual subgroup rate.

About the population sources:

  • For the 1996-2009 and 1999-2008 archive data, the denominator population shown is the number of persons age 15 and over in the state population estimates.
  • For Chlamydia rate calculations in years before the year 2000, the national population and the New York state population are limited to reporting areas.
  • See Reporting Issues and Population Data Sources for more information.



Reporting Issues:    Case reports may differ slightly from previously published data due to later revisions.

Electronic versus hardcopy reporting:  Beginning in 2003, all 50 states and the District of Columbia had converted from summary hardcopy reporting to electronic case-specific reporting via NETSS (with the exception of congenital syphilis, which is still reported on hardcopy forms by several areas). Much of the data in this system are based on aggregations from hardcopy report forms. Form CDC 73.688 is the quarterly form used from 1963 to 2002 to report summary data for all stages of syphilis, congenital syphilis, gonorrhea, chancroid, and chlamydia. Data from the quarterly form CDC 73.688 are used for the "By Gender" data set. Form CDC 73.2638 was used from 1981 to 2002 to report summary data for primary and secondary syphilis, gonorrhea, and chlamydia by age, race/ethnicity, and gender. Age, race/ethnicity and gender data reported on the form CDC 73.2638 for years 1996-2002 are used for the "By Age, Race/Ethnicity and Gender" data set.

Reporting entities differed in their ability to reconcile differences in total cases derived from summary hardcopy monthly, quarterly, and annual reports. Thus, there may be discrepancies in the total number of cases between competing data sources.

Missing age, race/ethnicity, and gender:  In the annual STD Surveillance Reports, unknown and missing values for age, race/ethnicity, and gender are redistributed based on the known distribution for these variables. In the WONDER online databases for STD morbidity, the value "Unknown" is retained for these three variables in the 1996-2008 archive data. Cases with unknown age are not included in the 1996-2009 data in WONDER. As a result, the data presented in this application may not match the STD Surveillance Report and may not accurately reflect true incidence or rates.

About Chlamydia reporting: Before 1996, Chlamydia reporting was voluntary, and thus sporadic. From 1995 - 2000, upstate New York did not report Chlamydia, and thus the total US denominator population for Chlamydia excludes the New York state population for the years 1995 - 2000. However, New York City did report Chlamydia before the year 2000, and the New York City population and Chlamydia cases are included for 1984 - 2000.

Since Chlamydia is often without symptoms, the number of cases reported is more a function of the amount of screening done and not the actual incidence. Screening occurs more often for women because Chlamydia is associated with Pelvic Inflammatory Disease and infertility. There is approximately a 4:1 ratio of women to men in Chlamydia case reporting due to screening practices. Refer to Tracking the Hidden Epidemics 2000 - Chlamydia for more information about reporting and gender differences. Traditionally male cases of Chlamydia have not been reported in the MMWR Notifiable Disease Annual Summaries.



Assurance of Confidentiality:    No personal information is included. Only summary statistics are available for this analysis from CDC WONDER.

If the total number of cases in a state in a year for a given disease is less than 4 (<4), then race information is suppressed for all cases of that disease in that state in that year. This suppression is accomplished by recoding Race to the "Race Suppressed" category for those cases of that disease in that state in that year.

Note: in the archive data released before July 2016, suppression is handled differently. Any figures representing less than three (3) cases are suppressed. For example, case counts and rates representing one (1) or two (2) cases are suppressed.





This page last reviewed: Tuesday, November 19, 2019
This information is provided as technical reference material. Please contact us at cwus@cdc.gov.