Measles virus infection diminishes preexisting antibodies that offer protection from other pathogens
Michael J. Mina, Stephen J. Elledge et al.
Abstract
Measles virus is directly responsible for more than 100,000 deaths yearly. Epidemiological studies have associated measles with increased morbidity and mortality for years after infection, but the reasons why are poorly understood. Measles virus infects immune cells, causing acute immune suppression. To identify and quantify long-term effects of measles on the immune system, we used VirScan, an assay that tracks antibodies to thousands of pathogen epitopes in blood. We studied 77 unvaccinated children before and 2 months after natural measles virus infection. Measles caused elimination of 11 to 73% of the antibody repertoire across individuals. Recovery of antibodies was detected after natural reexposure to pathogens. Notably, these immune system effects were not observed in infants vaccinated against MMR (measles, mumps, and rubella), but were confirmed in measles-infected macaques. The reduction in humoral immune memory after measles infection generates potential vulnerability to future infections, underscoring the need for widespread vaccination.
Indirect costs of adult pneumococcal disease and productivity-based rate of return to PCV13 vaccination for older adults and elderly diabetics in Denmark
J.P. Sevilla, Andrew Stawasz, Daria Burnes, Peter Bo Poulsen, Reiko Sato, David E. Bloom
Abstract
Objectives
To assess vaccines, HTAs should consider their broader socioeconomic effects, including those on market and nonmarket productivity (indirect costs, ICs). They should also consider decision criteria beyond cost-effectiveness that incorporate such effects, like social rates of return (RoR). We develop a method for measuring vaccination’s productivity benefits and social RoR and apply it to the case of PCV13 in older Danish adults.
Methods
We measure ICs from death and disability per treatment episode of inpatient community-acquired pneumonia (ICAP), outpatient CAP (OCAP), bacteremia, and meningitis in Danes aged 50–85. Losses include market and nonmarket work (housework, caregiving, and volunteering time valued at the unskilled wage), and span the duration of disability or, with death, the rest of life with background mortality risks. We calculate a RoR to PCV13 Adult in terms of averted direct costs (DCs) and ICs, allowing for herd effects and serotype replacement from child vaccination. We perform separate calculations for diabetics aged 65–85. We use data from EuroStat, Statistics Denmark, Danish prices/charges, and the published literature.
Results
ICs per episode exceed per capita GDP (PCGDP) for ICAP, approach PCGDP for bacteremia, exceed five times PCGDP for meningitis, and exceed 20 times DCs for OCAP. ICs consist largely of nonmarket productivity—specifically housework—lost to death. The RoR to PCV13 in the general older adult population is 149% and is driven by averted ICAP-related costs. In elderly diabetics, ICs per episode are higher and the RoR a stunning 1,191%. Main results are robust in sensitivity analyses.
Conclusions
The ICs of pneumococcal disease are considerable, even among older retired adults. The RoR to PCV13 in Danish older adults is high, especially for elderly diabetics, and compares very favorably with that of highly-regarded development interventions. Failing to account for productivity in valuing vaccination can result in considerable undervaluation.
Vaccination, Population Health, and European Leadership
David E. Bloom and Daniel Cadarette
Vaccination coverage in Europe is high in both historical and comparative perspectives. Based on available data, coverage for all antigens recommended for routine immunization by the World Health Organization (WHO)1 has increased or remained at high levels over the last one to two decades. For most of these vaccines, Europe is at or near the top of the list for coverage in comparison with other geopolitical regions of the world.
Although there are myriad causes of morbidity and mortality, it is not a coincidence that vaccine coverage is high in Europe and life expectancy is also long. In fact, life expectancy at birth in Europe has increased five years since 2000 and is higher than in any other WHO region. Europe’s high life expectancy is due in part to having the world’s lowest mortality rate for children under the age of five to which pediatric vaccination indisputably contributes and is further bolstered by high longevity for adults who have reached the older ages to which adult vaccination contributes.