Infectious Disease Surveillance

Public Health Surveillance is watching and studying information collected about diseases active in a specific population. This helps health care professionals to reduce the impact of the disease and improve health.

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Changes to Infectious Disease Reporting Fax Numbers (3/16/2022, NH Health Alert Network)

Disease Surveillance 

Public health data can be used in a variety of ways for the prevention and control of disease. This data can be used to monitor the health of the community and to detect large-scale public health events such as a bioterrorism event, pandemic influenza, or an outbreak of disease. The NH Bureau of Infectious Disease Control maintains a number of surveillance systems to monitor the health of NH citizens.

This program:

  • Watches and responds to diseases in a community.
  • Collects and studies information about more than 50 diseases that, by law, must be reported to public health.
  • Responds to outbreaks, increases of diseases, and events that may pose a threat to public health.

How Surveillance Works

Monitoring disease requires good communication between many organizations and facilities including health care providers, laboratories, and the Bureau of Infectious Disease Control.

For infectious disease surveillance to function well:

  • The Bureau of Infectious Disease Control receives reports of certain infectious diseases from health care related facilities, providers, and laboratories.
  • All reports and health data remain private and strictly confidential in accordance to federal and state laws.
  • Infectious Disease Reporting and Forms are available here.

Public health information can be used to

  • Prevent and control disease.
  • Early event detection.
  • Provide data to the public and community members.
  • Watch for changes or unusual increase of disease in a community.
  • Evaluate program effectiveness.
  • Stimulate research and inform policies.
  • Recognizing large-scale public health events such as:
    • A bioterrorism event
    • Widespread respiratory illness (example: influenza)
    • An outbreak of disease, and/or
    • Potential exposure to infectious disease (example: a breach in infection control or to highly infectious disease).

NH Surveillance Systems

Reportable Disease Surveillance System

Some infectious diseases are required by law (RSA 141-C ) to be reported by health care provider, facilities, and laboratories public health authorities. These diseases are contagious and can be cause serious illnesses if they are allowed to spread in a community.

Weekly disease reports from NH are sent to the US Centers for Disease Control and Prevention and added to reports from around the United States. All reports sent are de-identified in accordance with privacy laws to protect health related information.

This data allows for:

  • The detection of cluster or outbreaks of infectious diseases in order to respond and limit spread, or
  • To identify when a change has happened to a pathogen (disease causing organism) that is of concern and different treatments need to be considered.

Syndromic Surveillance

The Infectious Disease Surveillance Section within the Bureau of Infectious Disease Control maintains several surveillance systems to watch for symptoms and groups of symptoms that can be early warning signals for an emerging infectious, bioterrorism, or toxin related concern or problem. This is called syndromic surveillance.

  • Hospitals send information to the Infectious Disease Surveillance Section about the symptoms that emergency room patients are experiencing. These symptoms include fever, stomach pain, breathing difficulty, bleeding, and rashes among others.
  • This data is then utilized for the identification of clusters of related illnesses or symptoms in a specific geographical area or region of the state.
  • If a cluster is detected, then an investigation to identify a source may be initiated depending on the situation and what is known about any investigations already ongoing in the area of concern.

Below are a few of NH's surveillance systems used to watch for any unusual occurrence of infectious diseases, suspected bioterrorism events, or toxin exposures:

  • Automated Hospital Emergency Department Data Surveillance (AHEDD):
    • Collects real-time data from all 26 acute care hospital emergency departments in NH
    • Identifies potential public health threats and to monitor population health.
    • AHEDD has been a proven tool for public health investigations:
      • Detecting clusters or potential threats
      • Monitoring health conditions in the population, such as respiratory illness during influenza season, injuries during extreme weather events, and opioid drug overdoses.
  • Death Certificate Surveillance:
    • Includes review of documented causes of death that might indicate an outbreak,
    • Death due to infectious agent that is reportable, or
    • Be utilized during a public health threat such as bioterrorism event.
  • National Healthcare Safety Network (NHSN):
    • This CDC system is the nation’s most widely used means to:
      • Monitor health care related infections.
      • Gives government organizations and health care facilities the data needed to:
        • Identify problem areas
        • Track how well prevention efforts are working
        • Monitor health care associated infections.
  • NH School Absenteeism Reporting:
    • A voluntary system that records:
      • Total number of students absent in NH schools
      • How many students absent due to COVID quarantined status.
    • School Absenteeism Reporting
“In public health, we can’t do anything without surveillance. That is where public health begins.”

– David Satcher, MD, PHD

U.S. Surgeon General, 1998-2001

CDC - Public Health Surveillance and Data

NH Surveillance Programs: