¶ Counts include drug resistant and susceptible cases of Invasive Pneumococcal Disease. This condition was previously named Streptococcus pneumoniae invasive disease and cases were reported to CDC using different event codes to specify whether the cases were drug resistant or in a defined age group, such as <5 years.
** Prior to 2018, cases of paratyphoid fever were considered salmonellosis.
†† Prior to 2018, cases of paratyphoid fever were included as salmonellosis, but beginning in 2018 they are being published as paratyphoid fever.
§§ Includes the following categories: primary; secondary; early non-primary non-secondary (includes cases previously reported as early latent); and unknown duration or late (includes cases previously reported as late latent syphilis and cases previously reported as late syphilis with clinical manifestations).
¶¶ Data reported to ArboNET using the national surveillance case definition for congenital Zika virus infection (CSTE Position Statement 16-ID-01).
These are annual cases of selected infectious
national notifiable diseases from the National Notifiable Diseases Surveillance System (NNDSS).
NNDSS data reported by the 50 states, New York City, the District of Columbia, and the U.S. territories are
collated and published. Cases are reported by state health departments to CDC weekly. Because source datasets
may be updated as additional information is received, statistics in publications based on that source data may
differ from what is presented in these tables.
The list of nationally notifiable infectious diseases and conditions for 2018 and their national surveillance case definitions are
available by navigating to the Surveillance Case Definitions | CDC web page, selecting
"2018" for the notifiable condition list year, checking "infectious" conditions, and clicking "Get Notifiable List by Year".
This list incorporates the Council of State and Territorial Epidemiologists (CSTE) position statements approved in 2017
by CSTE for national surveillance, that were implemented in January 2018, including updated surveillance case definitions for
anthrax, shiga toxin-producing Escherichia coli, and syphilis. Perinatal hepatitis c virus infection became a new nationally
notifiable condition in 2018. While Carbapenemase Producing Carbapenem-Resistant Enterobacteriaceae (CP-CRE) was added to the
list of nationally notifiable diseases in 2018, reporting jurisdictions could not submit data for this condition since Office of
Management and Budget Paperwork Reduction Act approval was pending during 2018. Publication criteria for the finalized 2018 data
are available at
Guide to Interpreting Provisional and Finalized NNDSS Data.
Annual tables for 2016 and later years are available on CDC WONDER.
Annual summary reports from 1993-2015 are available as published in the
NNDSS annual tables since 1952 are available at CDC Stacks
(once in CDC Stacks select "Annual Reports" in the "Genre" box to the left).
For most conditions, national incidence rates are calculated as the number of reported cases for each infectious
disease or condition divided by the U.S. resident population for the specified demographic population or the total U.S.
resident population, multiplied by 100,000. When a nationally notifiable infectious condition is associated with a
specific age restriction, the same restriction was applied to the population in the denominator of the incidence rate
calculation. In addition, population data from reporting jurisdictions in which the disease or condition was not reportable
or not available were excluded from the denominator of the incidence rate calculations.
Population estimates for incidence rates are July 1st, 2018 estimates obtained from the National Center for Health Statistics (NCHS)
postcensal estimates of the resident population of the United States for April 1, 2010 - July 1, 2018, by year, county, single year
of age (range: 0 to 85 years), bridged-race (white, black or African American, American Indian or Alaska Native, Asian,
or Pacific Islander), Hispanic ethnicity (not Hispanic or Latino, Hispanic or Latino), and sex (Vintage 2018),
prepared under a collaborative arrangement with the U.S. Census Bureau. Population estimates for states released
June 25, 2019 are available at
Population estimates for territories are the 2018 mid-year estimates from the U.S. Census Bureau International Data Base, accessed on
June 26, 2019 at
The choice of population denominators
for incidence is based on the availability of population data at the time of publication preparation.
Age restrictions in the numerator and denominator are applied for the following childhood conditions:
Zika virus disease, congenital (age restriction in numerator and denominator is <1 year)
Zika virus infection, congenital (age restriction in numerator and denominator is <1 year)
Haemophilus influenzae, invasive disease <5 years (age restriction in numerator and denominator is <5 years)
Invasive pneumococcal disease <5 years (age restriction in numerator and denominator is <5 years)
Influenza associated pediatric mortality (age restriction in numerator and denominator is <18 years)
Infant botulism (age restriction in numerator and denominator is <1 year)
Congenital rubella syndrome (age restriction in numerator and denominator is <1 year)
Perinatal Hepatitis B infection (age restriction in numerator is ≤24 months, denominator is <24 months)
Perinatal Hepatitis C infection (age restriction in numerator is ≤36 months, denominator is <36 months)
Data for congenital syphilis are aggregated by the infant's year of birth. The rate for congenital syphilis is based upon the
number of reported cases per 100,000 live births, using natality data for 2018 (National Center for Health Statistics Natality 2018, as compiled from data
provided by the Vital Statistics Cooperative Program).
The mother's race and ethnicity are used for race- and ethnicity-specific rates of congenital syphilis cases. Congenital syphilis
data are published in Syphilis Statistics in the Sexually Transmitted Diseases (STD) surveillance
report (https://www.cdc.gov/std/syphilis/stats.htm) and in the historical archives of the STD surveillance
report (https://www.cdc.gov/std/stats/archive.htm). The STD surveillance
report (https://www.cdc.gov/std/syphilis/stats.htm) updates congenital syphilis cases and rates over time.
Surveillance data reported by other CDC programs might vary from data reported in these tables because of differences in
1) the date used to aggregate the data, 2) the timing of reports, 3) the source of the data, 4) surveillance case definitions,
and 5) policies regarding case jurisdiction (i.e., which jurisdiction should submit the case notification to CDC).
CDC acknowledges the Local, State, and Territorial Health Departments that collected the data from a range of case ascertainment
sources (e.g., health-care providers, hospitals, laboratories) and reported these data to
CDC's National Notifiable Diseases Surveillance System.