Surveillance Dona Schneider, PhD, MPH

 Surveillance is the ongoing, systematic collection, analysis, and interpretation of health data essential to the planning, implementation, and evaluation of public health practice, closely integrated with the timely feedback of these data to those who need to know. Centers for Disease Control

Surveillance can…  Estimate the magnitude of a problem  Determine geographic distribution of illness  Detect epidemics/outbreaks  Generate hypotheses, stimulate research  Evaluate whether control measures work  Monitor changes in infectious agents  Detect changes in health practices

Examples: Morbidity and Mortality Weekly Report SEER Cancer Registry US Vital Statistics

National Notifiable Diseases Surveillance System (NNDSS) – produces the data in the MMWR  The reportable diseases list is revised periodically by the Council of State and Territorial Epidemiologists (CSTE) and the Centers for Disease control (CDC)reportable diseases  States report their cases to the CDC  Internationally quarantinable diseases (i.e., cholera, plague and yellow fever) must be reported to the World Health Organization (WHO)

The Epidemic and Pandemic Alert and Response (EPR) Program at the WHO Monitors…  Anthrax Anthrax  Avian influenza Avian influenza  Crimean-Congo haemorrhagic fever (CCHF) Crimean-Congo haemorrhagic fever (CCHF)  Dengue/dengue haemorrhagic fever Dengue/dengue haemorrhagic fever  Ebola haemorrhagic fever Ebola haemorrhagic fever  Hepatitis Hepatitis  Influenza Influenza  Lassa fever Lassa fever  Marburg haemorrhagic fever Marburg haemorrhagic fever  Meningococcal disease Meningococcal disease  Plague Plague  Rift Valley fever Rift Valley fever  Severe Acute Respiratory Syndrome (SARS) Severe Acute Respiratory Syndrome (SARS)  Smallpox Smallpox  Tularaemia Tularaemia  Yellow fever Yellow fever

Surveillance for communicable diseases is important…  The world population is highly mobile  International travel and troop movements increase the risk of communicable disease transmission  Forced migration for war and famine, and voluntary immigration increase communicable disease risk

Types of Surveillance  Passive  Inexpensive, provider-initiated  Good for monitoring large numbers of typical health events  Under-reporting is a problem  Active  More expensive, Health Department-initiated  Good for detecting small numbers of unusual health events  Enhanced  Rapid reporting and communication between surveillance agencies and stakeholders  Best for detecting outbreaks and potentially severe public health problems

Syndromic surveillance  Allows us to identify groups of signs and symptoms that precede diagnosis and signal a sufficient probability of a case or an outbreak that warrants a further public health response  Example: EBOLA VIRUS

Sentinel Surveillance  Monitors  Sites – volcanos  Events – 9/11  Providers – ERs  Vectors/animals Rabies West Nile

SENTINEL EVENT Nov 12, :17 am Flight AA 587 Crashes in Rockaways 7-Zip Surveillance showed: 27 Obs / 10 Exp Resp Emergencies p< Obs / 16 Exp Hospital Events p<0.05

Investigation  Chart review in one hospital (9 cases)  Smoke Inhalation (1 case)  Atypical Chest Pain / Anxious (2 cases)  Shortness of Breath - Psychiatric (1 case)  Asthma Exacerbation (3 cases)  URI/LRI (2 cases)  Checked same-day logs at 2 hospitals Increase not sustained

Cipro and Doxycycline Prescriptions

Blood Lead Measurements Year Predicted blood lead Gasoline lead Observed blood lead Source: Pirkle et al JAMA 272:284-91, 1994 Lead used in gasoline (thousands of tons) Mean blood lead levels  g/dl

Reported Salmonella Isolates,* United States, *Data from Public Health Laboratory Information System (PHLIS). Source: CDC. Summary of notifiable diseases

Recent Occupational Monitoring Efforts for Sentinel Events Include…  Biodetection Systems (BDS) in NJ post offices to detect anthrax and soon, ricin  Biowatch, an air monitoring system in New York City and 30 other cities

Free Resources World Health Organization DISMOD Software Centers for Disease Control Epi Info and Epi Map

Good surveillance does not necessarily ensure the making of right decisions, but it reduces the chances of wrong ones. Alexander D. Langmuir NEJM 1963;268: