Principle Of Epidemology: Surveillance

PRINCIPLE OF EPIDEMIOLOGY SURVEILLANCE Surveillance 2 ¨ ¨ ¨ Surveillance is a fundamental role of public health. 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 dissemination of these data to those who need to know. monitor changes in disease frequency n levels of risks for specific diseases n Types 3 ¨ ¨ ¨ ¨ ¨ ¨ ¨ ¨ infectious diseases congenital malformations noncommunicable diseases environmental toxins Injuries illnesses after natural disasters such as hurricanes or earthquakes completeness of vaccination coverage prevalence of drug-resistant organisms such as drugresistant tuberculosis (TB) and malaria. Aim 4 ¨ providing policy makers with guidance for developing and implementing the best strategies for programs for disease prevention control mechanisms for information exchange ¤ standardized case definitions ¤ case definition 5 ¨ ¨ ¨ a set of uniform criteria used to define a disease for public health, intended to aid public health officials in recording and reporting cases different from a clinical definition PASSIVE SURVEILLANCE 6 ¨ ¨ ¨ ¨ ¨ available data on reportable diseases are used disease reporting is mandated or requested by the government or the local health authority responsibility for the reporting often falling on the health care provider or district health officer The completeness and quality of the data reported thus largely depend on this individual and his or her staff, who often take on this role without additional funds or resources underreporting and lack of completeness of reporting are likely Examples of passive surveillance 7 ¨ ¨ common sexually transmitted infections (syphilis, gonorrhea, human immunodeficiency virus/acquired immune deficiency syndrome [HIV/AIDS]) Other methods: ¤ flu outbreaks by assessing Google searches or social media passive reporting system 8 ¨ ¨ ¨ ¨ relatively inexpensive relatively easy to develop allows for international comparisons Reporting is generally more accurate when surveillance is active than when passive Active surveillance 9 ¨ a system in which project staff are specifically recruited to carry out a surveillance program. ¤ periodic field visits to health care facilities n n n ¤ case finding: Identify n n ¤ Clinics primary health care center Hospitals new cases of a disease deaths from the disease that have occurred Involves n n n interviewing physicians and patients reviewing medical records surveying villages and towns to detect cases n n periodically on a routine basis after an index case has been reported Global Surveillance for human infection with COVID-19 10 ¨ ¨ ¨ ¨ to monitor trends of the disease where human to human transmission occurs; rapidly detect new cases in countries where the virus is not circulating; provide epidemiological information to conduct risk assessments at the national, regional and global level provide epidemiological information to guide preparedness and response measures. Stages of Disease in an Individual 11