There are several types of surveillance systems, each serving different purposes:
Passive Surveillance: Relies on healthcare providers to report cases of infectious diseases. It is cost-effective but may underreport due to incomplete data. Active Surveillance: Involves proactive collection of data by public health officials. It is more resource-intensive but provides more accurate data. Sentinel Surveillance: Uses selected reporting sites to monitor disease trends. It is often used for diseases that are too widespread for comprehensive surveillance. Syndromic Surveillance: Focuses on symptom patterns rather than confirmed diagnoses. It is useful for early detection of outbreaks.
