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Injury and Illness Surveillance

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Global Burden Non-fatal Occ Illness & Injury, WHO

NON-FATAL OCCUPATIONAL INJURY

12%1%4%1%4%

66%

12%

SKIN

DUST/LUNG

RESP TOX

POISONING

PHYSICALAGENTS

REP TRAUMA

ALL OTHER

TRAUMATIC INJURY

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What is Occupational Surveillance?

• Systematic monitoring of:– Hazardous exposures– Adverse health events

FOR THE PURPOSE OF

• Prevention and control of:– Occupational hazards– Occupational diseases and injuries

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Types of Prevention

Primary- aimed at the individual who has potential for exposure; has not yet developed the disease. Goal is to change exposure conditionsSecondary- focus is the individual in whom the disease has started but the symptoms have not appeared. Goal is to reverse symptomsTertiary- aimed at individuals in whom the disease is symptomatic. Goal is cure or control of disease.

Types of Prevention

Primary – Target: those with potential for exposure; no disease yet. Goal: change exposure conditions

Secondary – Target: those with early stage of disease, no symptoms yetGoal: reverse disease, delay symptom onset

Tertiary – Target: those with clinical disease Goal: cure or control of disease.

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Healthy Asymptomatic Symptomatic

Worker Disease Disease

Primary Secondary Tertiary

Prevention Prevention Prevention

Opportunities for Prevention

time

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Why might you start an occupational surveillance program?

• Identify a problem and estimate its magnitude• Identify groups at risk• Monitor illness/injury trends in time and

geography• Identify cases, workplaces, and industries for

attention• Identify new illnesses• Identify new hazards

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How might you use a surveillance program?

• Prioritize health problems

• Determine whether you need an intervention program

• Evaluate progress, success, or failure of an intervention program

• Provide planning data for cost-effectiveness and benefit analysis

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Surveillance Techniques

• Keep log of new injuries and illnesses

• Examine existing databases for specific, sentinel diseases

• Conduct questionnaire survey of workers

• Conduct physical examinations

• Conduct laboratory examinations

• Conduct job hazard analysis

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How would you organize surveillance?

HAZARD BASED• Characterize hazards

– Observation/checklist

• Monitor environment• Test workers

HEALTH BASED• Acute or chronic

injuries/illnesses• List of insurance claims• Death certificates• Health questionnaire• Physical examination• Lab testing for disease

markers

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Techniques: Keep Log

Name Date of Injury

Diagnosis Causative

Factors

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Techniques: Examine existing databases

• Death certificates

• Hospital Discharges

• Laboratory reports

• Workers compensation reports

• National surveys

• Clinics that treat workers

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Techniques: Questionnaire Survey

• Demographic variables

• Work history: job tasks, hazards

• Health history: current, prior

• Symptoms

• Social, confounding factors

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Techniques: Physical examination

• Respiratory

• Skin

• Others

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Techniques: Laboratory Reports

• Require labs to report abnormal results above a specific level (e.g., Pb>25mg/dl)– May tie lab certification to reporting

• Set up reporting agency protocol (e.g., health department accepts reports on pre-made forms or electronically)

• Decide what level will trigger an intervention

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Techniques: Workplace investigation

• Investigate and record information about fatal injuries (i.e., accident investigation)

• Visit industries with a particular hazard

• Require reporting of certain injuries and set up a mechanism for reporting, however do not have to get every event to have an effective surveillance program

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What are the components of a surveillance system?

• Gather information on exposure & disease

• Analyze data

• Disseminate data in an organized form

• Use data to target or evaluate an intervention

• On-going

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Case Studies

For each of the cases, ask these questions1. What is the sentinel health event of

interest2. What is the best way to collect

information about it? (consider cost, time it takes to collect, how you will use results)

3. How could you use these results?

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Case One

You have heard about a small, rural community where most of the adults work in agriculture. There is concern about pesticide poisoning among adults and children because housing is located right next to farms.

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Case One

• Sentinel event: pesticide poisoning• Collect information:

– Questionnaire of community

– Blood testing of community

– Reports from local hospitals/clinics

• Use results:– For example, design pre and mid season cholinesterase

testing. Remove workers with decrease.

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Case Two

A scaffold fell off the side of a building on a windy day. Two workers were killed.

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Case Two

• Sentinel event: death

• Collect information:– accident investigation– review logs or medical records of injuries

• Use results: – Policy change to improve enforcement

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Case Three

A group of rubber workers notice that several of their co-workers have developed leukemia. They are concerned about the hazards of their industry.

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Case Three

• Sentinel event: Leukemia• Collect information:

– medical records of workers, if possible– conduct survey of workers– compare rates to those expected

• Use results: – If elevated rates, determine related exposure – reduce hazard– collect ongoing CBCs to follow trend;– inform workers of results of study