Veterinary Epidemiology and Zoonosis

PASSIVE AND ACTIVE SURVEILLANCE

Passive surveillance

• Passive surveillance has been described as the continuous monitoring of the existing disease status of the populations that are survived, using routinely collected data to produce outputs which inturn can feed into policy decisions.
  • Examples include reports of laboratory diagnosis, routine meat inspection findings and statutory notification of disease.
• Passive surveillance therefore essentially monitoring with the intention of acting on its findings.
• Passive surveillance uses the data that may be biased, frequently lacking denominator values, and so can not give unbiased estimates of disease frequency.

Active surveillance

• It involves the committed efforts of veterinary authorities to collect information commonly by undertaking surveys of specific diseases.
• Active surveillance based on well designed surveys, can produce the unbiased estimate.