secondary spread/secondary attack rate/secondary transmission
Term · Environment · MLC-T-ENV-025030
Definitions for these analogous terms were not found in most of the sources consulted. In individual studies, secondary transmission can be defined for the study in question, but those definitions may not be consistent across studies. The most restrictive definition limits secondary transmission to cases arising from direct human-to-human contact between a primary case (infected or ill) and the secondary case who becomes infected or ill from that contact. Broader definitions include secondary cases that arise from contact with fomites or contaminated food or water. In the cases where secondary transmission includes infection from pathogens from the environment, the case would not be considered secondary unless it occurs in the context of an outbreak where primary cases have already been identified. It may be difficult to distinguish between primary and secondary cases. For pathogens that infect only humans (no zoonosis or vectors) all infections ultimately arise from human to human contact or human to environment to human pathways. In these cases it is useful to limit the definition of secondary cases based on time and distance. For example, after a primary case is identified, only cases that occur within the time window of the primary case being infectious would be considered secondary transmission. For cases that occur during outbreaks a credible scenario for exposure between the primary and secondary cases would be important. Because there are many legitimate ways to define secondary transmission, it is important that the definition be elaborated for the situation being presented.
| Identifier | MLC-T-ENV-025030 |
|---|---|
| Field | Environment |
| Subject | Health and safety |
| References | Thesaurus of Terms Used in Microbial Risk Assessment |
Record as JSON
{
"id": "MLC-T-ENV-025030",
"term": "secondary spread/secondary attack rate/secondary transmission",
"field": "Environment",
"definition": "Definitions for these analogous terms were not found in most of the sources consulted. In individual studies, secondary transmission can be defined for the study in question, but those definitions may not be consistent across studies. The most restrictive definition limits secondary transmission to cases arising from direct human-to-human contact between a primary case (infected or ill) and the secondary case who becomes infected or ill from that contact. Broader definitions include secondary cases that arise from contact with fomites or contaminated food or water. In the cases where secondary transmission includes infection from pathogens from the environment, the case would not be considered secondary unless it occurs in the context of an outbreak where primary cases have already been identified. It may be difficult to distinguish between primary and secondary cases. For pathogens that infect only humans (no zoonosis or vectors) all infections ultimately arise from human to human contact or human to environment to human pathways. In these cases it is useful to limit the definition of secondary cases based on time and distance. For example, after a primary case is identified, only cases that occur within the time window of the primary case being infectious would be considered secondary transmission. For cases that occur during outbreaks a credible scenario for exposure between the primary and secondary cases would be important. Because there are many legitimate ways to define secondary transmission, it is important that the definition be elaborated for the situation being presented.",
"subject": "Health and safety",
"references": [
"Thesaurus of Terms Used in Microbial Risk Assessment"
],
"url": "https://mlchart.com/terminology/environment/secondary-spread-secondary-attack-rate-secondary-transmission/"
}
Record 25,030 of 30,736 in Environment terminology (MLC-0121). Request the full dataset.