| Title |
Herd immunity and herd effect: new insights and definitions
|
|---|---|
| Published in |
European Journal of Epidemiology, July 2000
|
| DOI | 10.1023/a:1007626510002 |
| Pubmed ID | |
| Authors |
T. Jacob John, Reuben Samuel |
| Abstract |
The term herd immunity has been used by various authors to conform to different definitions. Earlier this situation had been identified but not corrected. We propose that it should have precise meaning for which purpose a new definition is offered: "the proportion of subjects with immunity in a given population". This definition dissociates herd immunity from the indirect protection observed in the unimmunised segment of a population in which a large proportion is immunised, for which the term 'herd effect' is proposed. It is defined as: "the reduction of infection or disease in the unimmunised segment as a result of immunising a proportion of the population". Herd immunity can be measured by testing a sample of the population for the presence of the chosen immune parameter. Herd effect can be measured by quantifying the decline in incidence in the unimmunised segment of a population in which an immunisation programme is instituted. Herd immunity applies to immunisation or infection, human to human transmitted or otherwise. On the other hand, herd effect applies to immunisation or other health interventions which reduce the probability of transmission, confined to infections transmitted human to human, directly or via vector. The induced herd immunity of a given vaccine exhibits geographic variation as it depends upon coverage and efficacy of the vaccine, both of which can vary geographically. Herd effect is determined by herd immunity as well as the force of transmission of the corresponding infection. Clear understanding of these phenomena and their relationships will help improve the design of effective and efficient immunisation programmes aimed at control, elimination or eradication of vaccine preventable infectious diseases. |
X Demographics
The data shown below were collected from the profiles of 67 X users who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 10 | 15% |
| United Kingdom | 6 | 9% |
| Australia | 4 | 6% |
| France | 2 | 3% |
| Mexico | 2 | 3% |
| Ireland | 1 | 1% |
| Switzerland | 1 | 1% |
| Colombia | 1 | 1% |
| Indonesia | 1 | 1% |
| Other | 3 | 4% |
| Unknown | 36 | 54% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 61 | 91% |
| Scientists | 3 | 4% |
| Practitioners (doctors, other healthcare professionals) | 2 | 3% |
| Science communicators (journalists, bloggers, editors) | 1 | 1% |
Mendeley readers
The data shown below were compiled from readership statistics for 410 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 3 | <1% |
| Brazil | 3 | <1% |
| United Kingdom | 2 | <1% |
| Kenya | 1 | <1% |
| Bangladesh | 1 | <1% |
| New Zealand | 1 | <1% |
| Australia | 1 | <1% |
| Unknown | 398 | 97% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 72 | 18% |
| Student > Bachelor | 66 | 16% |
| Researcher | 42 | 10% |
| Student > Ph. D. Student | 37 | 9% |
| Other | 23 | 6% |
| Other | 69 | 17% |
| Unknown | 101 | 25% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 94 | 23% |
| Agricultural and Biological Sciences | 59 | 14% |
| Social Sciences | 21 | 5% |
| Biochemistry, Genetics and Molecular Biology | 19 | 5% |
| Nursing and Health Professions | 16 | 4% |
| Other | 86 | 21% |
| Unknown | 115 | 28% |
Attention Score in Context
This research output has an Altmetric Attention Score of 121. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 23 March 2024.
All research outputs
#348,999
of 25,661,882 outputs
Outputs from European Journal of Epidemiology
#62
of 1,815 outputs
Outputs of similar age
#168
of 39,469 outputs
Outputs of similar age from European Journal of Epidemiology
#1
of 6 outputs
Altmetric has tracked 25,661,882 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 98th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 1,815 research outputs from this source. They typically receive a lot more attention than average, with a mean Attention Score of 39.1. This one has done particularly well, scoring higher than 96% of its peers.
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