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Scientific Data Documentation
National Notifiable Disease Surveillance System, 1989

 The NNDSS file in WONDER contains nationally notifiable diseases
 reported weekly by State and Territorial epidemiologists to the
 Division of Surveillance and Epidemiology (DSE), Epidemiology
 Program Office (EPO), Centers for Disease Control (CDC), using
 the National Electronic Telecommunications System for
 Surveillance (NETSS).  The operation of NETSS is facilitated by
 agreements between CDC and the Council of State and Territorial
 Epidemiologists (CSTE) on reportable conditions, protocols for
 formatting and transmitting data, and standard case definitions.
 Designated staff members in each participating agency provide and
 prepare the data for weekly publication in the "Morbidity and
 Mortality Weekly Report" (MMWR).

 Over 40 diseases are reported through this system.  In WONDER,
 the following variables are available for events reported as
 individual case records:  age, gender, race/ethnicity, county of
 residence, State, and MMWR week of report; from aggregate
 records, State and MMWR week of report.  Line-listed data are not
 available from this file.


 Data reported for 1989 by Arizona, California, Nebraska, and
 Wyoming are represented as aggregate counts, since these states
 were not reporting individual case data for all of 1989.

 For some events (amebiasis, aseptic meningitis, chickenpox,
 Hansen disease (leprosy), measles, mumps, pertussis, rheumatic fever,
 rubella, and tetanus), cases may be reported to the State health department
 by number only.  For these events, United States distributions by
 county, age, gender, and race/ethnicity will include only those
 cases reported as individual records and the distribution will
 not equal the total cases reported.

 Case counts by age, gender, and race/ethnicity are available from
 this file at State level only due to confidentiality guidelines.

 Data for AIDS, animal rabies, gonorrhea, primary and secondary
 syphilis, congenital syphilis, and tuberculosis are more likely
 to be reported as aggregate counts in this file.  These data are
 based on provisional weekly reports to NETSS, and the totals may
 not agree with the case counts provided by the National Center
 for Infectious Diseases (NCID) or the National Center for
 Prevention Services (NCPS) for publication in the MMWR "Summary
 of Notifiable Diseases."  Reports for all other events can be
 verified by reference to the MMWR "Summary of Notifiable


 Event Codes
      Disease or Injury                  Code
      AIDS                               10560
      Amebiasis                          11040
      Anthrax                            10350
      Aseptic meningitis                 10010
      Botulism, foodborne                10530
      Botulism, infant                   10540
      Botulism, other                    10550
      Brucellosis                        10020
      Chickenpox (varicella)             10030
      Cholera                            10470
      Congenital rubella syndrome        10370
      Congential syphilis                10316
      Diphtheria                         10040
      Encephalitis, primary              10050
      Encephalitis, post chickenpox      10070
      Encephalitis, post mumps           10080
      Encephalitis, post other           10090
      Gonorrhea                          10280
      Hepatitis A                        10110
      Hepatitis B                        10100
      Hepatitis non-A, non-B             10480
      Hepatitis, unspecified             10120
      Legionellosis                      10490
      Leprosy (Hansen disease)           10380
      Leptospirosis                      10390
      Malaria                            10130
      Measles, imported                  10510
      Measles, indigenous                10500
      Meningococcal infection            10150
      Mumps                              10180
      Pertussis                          10190
      Plague                             10440
      Poliomyelitis, paralytic           10410
      Psittacosis                        10450
      Rabies, animal                     10340
      Rabies, human                      10460
      Rheumatic fever                    11050
      Rocky Mountain spotted fever       10250
      Rubella                            10200
      Salmonellosis                      11000
      Shigellosis                        11010
      Syphilis, primary and secondary    10310
      Tetanus                            10210
      Toxic-shock syndrome               10520
      Trichinosis                        10270
      Tuberculosis                       10220
      Tularemia                          10230
      Typhoid fever                      10240
      Typhus murine                      10260

      These five-digit codes are similar to the three-digit codes
      presently used for reporting notifiable diseases to the
      MMWR.  These codes, although not universally used, are
      easier and simpler to use than universal coding schemes,
      such as ICD-9.

      Note that some events are represented by more than one code
      (botulism, encephalitis, hepatitis, measles, sexually-
      transmitted diseases).  Selection of more than one event
      will be possible in a future enhancement of this file in
      WONDER, such as ALL measles, ALL hepatitis, ALL sexually-
      transmitted diseases.

      Selection of an event which produces the message "There were
      no cases found with these criteria" should be interpreted as
      no cases reported.

      Selection of an event will sometimes produce a message that
      the event is not notifiable in some states.  This
      information can be verified by reference to the MMWR
      "Summary of Notifiable Diseases," in the table of reported
      cases by geographic division and area.

 State and County Codes

      Coding for States and counties is based on Federal
      Information Processing Standards (FIPS).  This scheme
      designates a two-digit code for each State based on
      alphabetical order and a three-digit code for each county
      generally using odd numbers to allow for the addition of new
      counties.  The code for unknown county is 999.

      Distributions for the United States include Washington, D.C.
      and New York City as separate reporting areas.  Selection of
      the State of New York will EXCLUDE New York City.
      Territories (American Samoa, Guam, Commonwealth of the
      Northern Mariana Islands, Puerto Rico, and the Virgin
      Islands) can be selected separately.

      Selection of a group of states or territories will be
      possible in a future enhancement of this file in WONDER.

      Counties reporting zero (0) or less than four (4) cases are
      not shown.

 Age Groups
      Selection by age group will provide distributions from all
      individual case records.  Distributions may not equal total
      cases reported for the event if some states reported
      aggregate counts.

      Selection by gender will provide distributions from all
      individual case records.  Distributions may not equal total
      cases reported for the event if some states reported
      aggregate counts.

      Selection by race/ethnicity will provide distributions from
      all individual case records.  Distributions may not equal
      total cases reported for the event if some states reported
      aggregate counts.

 MMWR Week
      The weekly report of notifiable diseases covers the week
      preceding the report's publication.  The week begins Sunday
      and ends on Saturday.  The case count for MMWR week
      represents cases reported and entered into the State's
      surveillance system during the current reporting week. A
      week-ending calendar is published by the Division of
      Surveillance and Epidemiology, EPO, CDC, which is available
      through the help facility for MMWR week in WONDER.


 In 1878 an Act of Congress authorized the collection of morbidity
 reports by the Public Health Service to establish quarantine
 measures for diseases such as cholera, smallpox, plague, and
 yellow fever.  In 1893 another Act authorized the collection of
 information on a weekly basis from state and municipal
 authorities throughout the United States, and gradually an
 increasing number of states submitted monthly and annual
 summaries to the Public Health Service.  It was not until 1925,
 however, that all states began to report regularly.
 Responsibilities for data collection and analysis were
 subsequently transferred several times within the Public Health
 Service.  Responsibility for collecting the weekly data on the
 notifiable diseases and publishing them in the "Morbidity and
 Mortality Weekly Report" (MMWR) and the annual "Summary of
 Notifiable Diseases" resides in the Epidemiology Program Office
 at CDC.

 Up until the early 1980's, weekly reports of aggregate counts of
 the notifiable diseases were made by State health departments to
 CDC by telephone.  However, in 1984 the Epidemiologic
 Surveillance Project (ESP) was initiated by CDC and the State
 Epidemiologists in Colorado, Michigan, Minnesota, New York,
 Washington, and Wisconsin to demonstrate the feasibility of
 transmitting disease surveillance data electronically from State
 health department computer systems to the CDC.  From those
 beginnings ESP has steadily grown so that now all of the States,
 New York City, the District of Columbia, and Puerto Rico are
 participating, and the name was changed to NETSS to reflect its
 nationwide scope.

 Three concepts were integral to the initial design of this
 system.  First, each State health department could continue to
 use its existing computerized disease surveillance system to
 transmit data to CDC.  Second, specific data concerning each case
 of a reportable disease would be transmitted to CDC.  Finally,
 these computerized case records would supplant the States' weekly
 telephone reporting to the NNDSS.  This is the system that
 provides the information that is published in Tables 1 and 2 of
 the MMWR.

 Disease surveillance systems vary widely from State to State. The
 diseases under surveillance, the reporting sources and the size
 of the systems may differ.   NETSS was designed to allow States
 to use their existing disease databases as much as possible.

 These State systems have implemented their systems on a variety
 of computers using different programs and data formats.  In
 October 1991, thirty-eight reporting areas are using a software
 package called Epi Info for their surveillance system.  This is
 an epidemiologic data base and analysis system that has been
 developed and supported by the Division of Surveillance and
 Epidemiology of the Epidemiology Program Office at CDC.  In some
 States CDC has provided technical support.  Such support has been
 limited to consultation regarding system implementation and in
 some cases 3 to 5 days of onsite technical assistance to
 computerize their surveillance system.

 In general, similar steps are followed by all States currently
 participating in NETSS.

      1. Data are reported to the State health department from
      county health departments, hospitals, physicians, and
      laboratories.  These data are entered into the State/county
      computer and analyzed for local needs.

      2. Weekly, a program is run against the State surveillance
      data base that selects the records to be transmitted to CDC
      and converts the record format and codes from the State
      conventions to the NETSS report format.  A subfile of the
      selected records, in the NETSS format, is created.

      3. Most of the State reports are transmitted through the
      Public Health Network on BT North America (known by users as

      4. An electronic mail message containing the weekly NETSS
      file is sent to the CDC mailbox in Dialcom.

      5. CDC staff reads these messages, uploads the data to the
      CDC mainframe computer, edits it, and then updates the NETSS
      master database.

      6. Each week a summary report is sent to each State
      describing the number of records transmitted, the number of
      new records, updates, and records deleted.  In addition,
      coding errors are indicated and a year-to-date summary of
      the State's reports is included.

      7. Should corrections be necessary the State retransmits the
      correct data and the incorrect record is revised.

 NETSS data are summarized and published weekly in the MMWR and
 more extensive analyses are included in the MMWR annual summary.

This page last reviewed: Thursday, January 28, 2016
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