herd immunity


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herd immunity

[′hərd i‚myü·nəd·ē]
(immunology)
Immunity of a sufficient number of individuals in a population such that infection of one individual will not result in an epidemic.
References in periodicals archive ?
Findings and discussion Vaccination coverage and herd immunity
This is not just a problem when assessing the population at risk of meningococcal disease, but also for other recent vaccine programs, such as varicella vaccine, where herd immunity is also an important part of the overall vaccine effect.
We recognize, however, that neutralization tests do not capture all aspects of herd immunity in a population.
As long as herd immunity remains strong, these free riders on the immunization system have been exposing their children and others to a relatively slight chance of disease.
But the hope for herd immunity against HPV anytime soon is fading fast in most of the West.
But Dr Holtby added: "MMR uptake rates need to be at least 95pc to achieve the herd immunity protection levels recommended by the World Health Organisation if the widespread return of measles is to be prevented.
The results of the study mean that, over time, herd immunity can develop, which is the "first step" towards eradicating cervical cancer caused by HPV.
herd immunity to infections produced by vaccination or the existence of a specific law--that have no analogue at the individual level, unlike the aggregate and environmental variables.
That's at or below the rate required for herd immunity to measles - the collective immunity that is gained when the percentage of vaccinated people is high enough to act as a firewall against the spread of a disease.
Dr Saif said these people either did not know or simply overlooked the fact that while protecting their children against polio were actually exposing other under five children to the virus as it is only OPV that provides herd immunity against the crippling disease.
Matt Brash, BVetMed MRCVS, who runs a small animal veterinary clinic in North Yorkshire and is star of the TV show 'Zoo Vet at Large' comments: "Many pet owners simply don't realise that their pets are at risk of disease but, in the meantime, less than half of all dogs and cats are vaccinated, which is well below the amount needed to protect the pet population through herd immunity.
Currently, Pennsylvania is below the 95 percent benchmark to achieve herd immunity.