An infection rate or incident rate is the

probability Probability is a branch of mathematics and statistics concerning events and numerical descriptions of how likely they are to occur. The probability of an event is a number between 0 and 1; the larger the probability, the more likely an e ...

risk In simple terms, risk is the possibility of something bad happening. Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environ ...

of an

infection An infection is the invasion of tissue (biology), tissues by pathogens, their multiplication, and the reaction of host (biology), host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmis ...

in a

population Population is a set of humans or other organisms in a given region or area. Governments conduct a census to quantify the resident population size within a given jurisdiction. The term is also applied to non-human animals, microorganisms, and pl ...

. It is used to measure the frequency of occurrence of new instances of infection within a population during a specific time period.

\text = K \times \frac

The number of infections equals the cases identified in the study or observed. An example would be

HIV The human immunodeficiency viruses (HIV) are two species of '' Lentivirus'' (a subgroup of retrovirus) that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the im ...

infection during a specific time period in the defined population. The population at risk are the cases appearing in the population during the same time period. An example would be all the people in a city during a specific time period. The constant ''K'' is assigned a value of 100 to represent a percentage. An example would be to find the percentage of people in a city who are infected with HIV: 6,000 cases in March divided by the population of a city (one million) multiplied by the constant (''K'') would give an infection rate of 0.6%. Calculating the infection rate is used to analyze trends for the purpose of infection and disease control. An online infection rate calculator has been developed by the

Centers for Disease Control and Prevention The Centers for Disease Control and Prevention (CDC) is the National public health institutes, national public health agency of the United States. It is a Federal agencies of the United States, United States federal agency under the United S ...

that allows the determination of the streptococcal A infection rate in a population. __TOC__

Clinical applications

Health care facilities routinely track their infection rates according to the guidelines issued by the

Joint Commission The Joint Commission is a United States-based nonprofit tax-exempt 501(c) organization that accredits more than 22,000 US health care organizations and programs. The international branch accredits medical services from around the world. A majori ...

. The

healthcare-associated infection A hospital-acquired infection, also known as a nosocomial infection (from the Greek , meaning "hospital"), is an infection that is acquired in a hospital or other health care, healthcare facility. To emphasize both hospital and nonhospital sett ...

(HAI) rates measure infection of patients in a particular hospital. This allows rates to compared with other hospitals. These infections can often be prevented when healthcare facilities follow guidelines for safe care. To get payment from Medicare, hospitals are required to report data about some infections to the Centers for Disease Control and Prevention's (CDC's) National Healthcare Safety Network (NHSN). Hospitals currently submit information on

central line-associated bloodstream infection A central venous catheter (CVC), also known as a central line (c-line), central venous line, or central venous access catheter, is a catheter placed into a large vein. It is a form of venous access. Placement of larger catheters in more centra ...

s (CLABSIs), catheter-associated urinary tract infections (CAUTIs), surgical site infections (SSIs), MRSA Bacteremia, and ''

C. difficile ''Clostridioides difficile'' ( syn. ''Clostridium difficile'') is a bacterium known for causing serious diarrheal infections, and may also cause colon cancer. It is known also as ''C. difficile'', or ''C. diff'' (), and is a Gram-positive spec ...

'' laboratory-identified events. The public reporting of these data is an effort by the

Department of Health and Human Services The United States Department of Health and Human Services (HHS) is a cabinet-level executive branch department of the US federal government created to protect the health of the US people and providing essential human services. Its motto is ...

. For meaningful comparisons of infection rates, populations must be very similar between the two or more assessments. However, a problem with mean rates is that they cannot reflect differences in risk between populations,

References

External links

The Society for Healthcare Epidemiology of America
epidemiologists or physicians in infection control.
Association for Professionals in Infection Control and Epidemiology
infection prevention and control professionals.
The Certification Board of Infection Control and Epidemiology, Inc.
Epidemiology Medical hygiene Infectious diseases {{Med-stub