Number Needed To Vaccinate Research Articles

Could a federal program to promote influenza vaccination among elders be cost-effective?

BackgroundInfluenza-related mortality predominately and disproportionately impacts the elderly. Rates of annual influenza vaccination among the elderly are approximately 65%, far below the Healthy People 2010 target of 90%. We estimated the cost-effectiveness of a 10-year federal program to promote influenza vaccine, intended to increase vaccination rates among persons ≥65 years old. MethodsPublished estimates regarding influenza-associated mortality rates and vaccine efficacy among the US elderly were used to calculate the number needed to vaccinate (NNV) to prevent one all-cause death due to influenza, as well as the mortality reduction expected from increased vaccination rates. The costs per life-year saved were estimated for a hypothetical federal promotional campaign, patterned after a direct-to-consumer (DTC) advertising program (2006–2015). The base case scenario presumed a 25-percentage-point increase in vaccination rates to 90%; in sensitivity analyses, we examined programs that increased rates by 10–20 points. ResultsThe base case NNV was 1116 (95% CI: 993–1348). Over the 10-year DTC-style influenza vaccine promotion program, 6516 (5576–7435) elderly lives would be saved. The incremental cost-effectiveness (C/E) of the program was $16,300 ($11,347–$25,174) per life-year saved in 2006 and increased to $199,906 ($138,613-$307,423) per life-year saved by 2015. Overall, the C/E for the 10-year program was $37,621 ($32,644–$43,939) per life-year saved. Programs that yielded a 15-percentage-point increase or less in vaccination rates would have C/E values exceeding $50,000 per life-year saved and save fewer than 4000 total lives. ConclusionsDTC-style promotional campaigns for influenza vaccine among elders may represent a cost-effective strategy for the federal government to pursue as a means of increasing elders' vaccination rates and reducing influenza-related mortality.

The number needed to vaccinate (NNV) and population extensions of the NNV: comparison of influenza and pneumococcal vaccine programmes for people aged 65 years and over

The number needed to treat (NNT) and population extensions of the NNT describe the population outcomes of disease treatment, usually for chronic diseases. We have developed similar measures for vaccine preventable diseases based on the number needed to vaccinate. These measures quantify the number of people, or the number of vaccine doses, needed to prevent one event due to disease per year and allow the calculation of the vaccine cost to prevent one event due to disease per year. We used this method to compare influenza and pneumococcal vaccine programmes for people aged 65 years or more. We calculated the vaccine cost ($AUD) to prevent a case of disease, a hospitalisation or a death due to influenza or invasive pneumococcal disease each year in this age group. For influenza, the vaccine costs were $598 to prevent one case per year, $10,787 per hospitalisation prevented and $74,801 per death prevented each year. We assumed all cases of invasive pneumococcal disease were hospitalised so the vaccine cost of $11,494 per case prevented was the same as the vaccine cost per hospitalisation prevented, while the vaccine cost per death prevented each year was $49,972. These results suggest the vaccine costs for the prevention of one hospitalisation or one death each year due to invasive pneumococcal disease among the elderly in Australia would be similar to the costs for the prevention of one hospitalisation or death due to influenza.

Adolescent and adult pertussis vaccination: computer simulations of five new strategies

Approximately one million adult pertussis cases occur annually in the US, and infants still die from pertussis. Computer simulations were used to predict the impact of vaccination of children, adults and/or adolescents, and household members of newborns (cocoon strategy). Childhood vaccination greatly reduced cases in children, but increased the incidence in adolescents and adults. Routine adolescent and adult vaccination had a large direct effect, whereas the cocoon strategy had a predominantly indirect effect on young infants. The number needed to vaccinate (NNV) to prevent a case of typical pertussis in the entire population was lowest for the adolescent strategy. The cocoon strategy had the lowest NNV to prevent a case of typical pertussis in young infants. The current vaccination schedule, local epidemiological data, age-specific cost of pertussis cases, and accessibility of the target population will determine which strategy has the highest likelihood of success in achieving the public health goal.

The number needed to vaccinate (NNV) and population extensions of the NNV: comparison of influenza and pneumococcal vaccine programmes for people aged 65 years and over

The number needed to treat (NNT) and population extensions of the NNT describe the population outcomes of disease treatment, usually for chronic diseases. We have developed similar measures for vaccine preventable diseases based on the number needed to vaccinate. These measures quantify the number of people, or the number of vaccine doses, needed to prevent one event due to disease per year and allow the calculation of the vaccine cost to prevent one event due to disease per year. We used this method to compare influenza and pneumococcal vaccine programmes for people aged 65 years or more. We calculated the vaccine cost ($AUD) to prevent a case of disease, a hospitalisation or a death due to influenza or invasive pneumococcal disease each year in this age group. For influenza, the vaccine costs were $598 to prevent one case per year, $10,787 per hospitalisation prevented and $74,801 per death prevented each year. We assumed all cases of invasive pneumococcal disease were hospitalised so the vaccine cost of $11,494 per case prevented was the same as the vaccine cost per hospitalisation prevented, while the vaccine cost per death prevented each year was $49,972. These results suggest the vaccine costs for the prevention of one hospitalisation or one death each year due to invasive pneumococcal disease among the elderly in Australia would be similar to the costs for the prevention of one hospitalisation or death due to influenza.