New Data Release: Infectious Disease/STD Surveillance

2010 CDC Report

The Centers for Disease Control and Prevention (CDC) describes the transmission of Sexually Transmitted Diseases (STD) as a “hidden epidemic”, citing the social stigma and general reluctance toward open discussion about the issue within a community. In its annual report, Sexually Transmitted Disease Surveillance 2010, the CDC presents its findings on trends and changes across the country for STDs that are deemed Nationally Notifiable. Now on PolicyMap, we are providing data for chlamydia, gonorrhea, and primary and secondary syphilis. This data is available as the incidence of disease – meaning, new cases reported each year.

Interpreting Data

Because these infectious disease indicators are new for our health tab – and generally unique for PolicyMap – we would like to provide a very brief introduction to epidemiology and biostatistics. First, is to explain that notifiable is different from reportable. Notifiable diseases are reported on a voluntary basis from the state and territorial jurisdictions to the CDC. In some cases, if a disease is not reportable (mandatory to report) at the local or state level, the data may not exist to provide to the CDC. This can lead to some variability in the data between localities. The second thing is the difference between incidence and prevalence. The two terms, while they both address the existence of disease within a population, identify two very different statistics. Incidence explains specifically newly diagnosed cases, while prevalence deals with the total amount of people living with disease within a given population. The difference is in comparing the risk of contraction (incidence) versus the social burden associated with the disease (prevalence).

National Profile

  • 1,307,893 cases of chlamydia were reported in 2010 (5.1% increase from previous year)
  • In 2010, this was the highest number of cases ever reported to the CDC for any condition
  • In 2010, 426.0 cases per 100,000 people (610.6 cases per 100,000 females, 233.7 cases per 100,000 males)

  • 309,341 cases of gonorrhea were reported in 2010 (2.8% increase from previous year)
  • From 2006-2009, decreased to the lowest rate since national reporting began
  • In 2010, 100.8 cases per 100,000 people (106.5 cases per 100,000 females, 94.1 cases per 100,000 males)

  • 13,774 cases of primary and secondary syphilis were reported in 2010 (decreased 21% in women, 1.3% in men)
  • By 2000, it had decreased to the lowest rate since reporting began in 1941, but then increased each year from 2001 to 2009.

Mapping the Data

This data is now available to all users on PolicyMap. Indicators for each of the three diseases are provided by both state and county for each year ranging from 2000 to 2010. There are many disparities in the risk associated with STDs that vary by age, race, gender, sexual behavior, sexual orientation, and location. Though county-level data is not available for each of these individual demographic groupings, the geographic distribution of total cases/populations is still fairly significant. These maps present distinct patterns of disease spread across the South, which appears consistent for each of the three diseases. Though this data can be very valuable, it cannot explain conditions with absolute certainty. Variability over time and between geographies can exist due to inconsistencies in reporting methods. Additionally, due to the nature of sexually transmitted diseases, cases without symptoms can be transmitted without the knowledge of either partner and so reporting rates can be a result of the amount of screening that is occurring, rather than the true incidence of the disease. While many public health initiatives and community interventions exist and continue to develop, there are still many barriers and challenges to standardizing methods of surveillance, prevention, and control of these diseases.