Thrombosis and thromboembolism: Brighton collaboration case definition and guidelines for data collection,analysis, and presentation of immunization safety data

This is a Brighton Collaboration case definition of thrombosis and thromboembolism to be used in the evaluation of adverse events following immunization, and for epidemiologic studies for the assessment of background incidence or hypothesis testing. The case definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of SARS-CoV-2 vaccines. The case definition format of the Brighton Collaboration was followed to develop a consensus definition and defined levels of certainty, after an exhaustive review of the literature and expert consultation. The document underwent peer review by the Brighton Collaboration Network and by selected expert reviewers prior to submission.     

Factors and considerations for establishing and improving seasonal influenza vaccination of health workers: Report from a WHO meeting,January 16–17, Berlin,Germany

Health workers represent an important target group for seasonal influenza vaccination because of their increased risk of infection as well as the risk of transmitting infection to vulnerable patients in the health care setting. Moreover, seasonal vaccination of health workers contributes to pandemic preparedness. However, many countries, especially in Africa and Asia, do not have policies for health worker influenza vaccination. In countries where such policies exist, vaccination coverage is often low. The World Health Organization (WHO) is developing a manual to guide the introduction of seasonal influenza vaccination of health workers. An Independent External Advisory Group (IEAG) that is advising WHO on the content of the manual met to discuss issues that are relevant and often unique to health worker vaccination. This meeting report summarizes the main issues that were discussed and the outcomes of the discussion. The issues include policy considerations, including the evidence in support of health worker vaccination; categorization and prioritization of health workers; the choice of vaccination strategy; its integration into broader health worker vaccination and occupational health policies; planning and management of vaccination, particularly the approaches for communication and demand generation; and the challenges with monitoring and evaluation of health worker vaccination, especially in low and middle-income countries.     

How cost effective is switching universal vaccination from PCV10 to PCV13? A case study from a developing country

BackgroundChildren immunization with pneumococcal conjugate vaccine (PCV) had profound public health effects across the globe. Colombian adopted PCV10 universal vaccination, but PCV incremental impact need to be revalued. The objective of this analysis was to estimate the cost-effectiveness of switch to PCV13 versus continue PCV10 in Colombian children.MethodsA complete economic analysis was carried-out assessing potential epidemiological and economic impact of switching from PCV10 to PCV13. Epidemiological information on PCV10 impact was obtained from lab-based epidemiological surveillance on pneumococcal isolates at the Colombian National Institute of Health. Economic inputs were extracted from the literature. Incremental PCV13 effectiveness was based in additional serotypes included. Comparisons among alternatives were evaluated with the Incremental Cost-Effectiveness Ratio (ICER) at a willingness to pay of one GDP per capita (USD$ 6631) per Year of Live Saved (YLS). All costs were reported in 2014USD. Deterministic and probabilistic sensitivity analyses were performed, and 95% confidence interval reported.ResultsAfter four years using PCV10 for universal vaccination on children the Colombian health surveillance system showed a relative increment on non PCV10 isolates. To change from PCV10 to PCV13 would avoid 587 (CI95% −49–1008) ambulatory Rx community-acquired pneumoniae (CAP), 1622 (CI95% 591–2343) Inpatient RxCAP, 10 (CI 95% 6–11) pneumococcal meningitis, and 79 (CI95% 76–98) deaths. ICER per YLS was USD$ 2319 (CI95% Dominated – USD$ 4225) for Keep-PCV10 and USD$ 1771 (CI95% USD$ 1285–9884) for Switch-to PCV13. In spite of its cost-effectiveness Keep-PCV10 is an extended dominated alternative and Switch-to PCV13 would be preferred. Results are robust to parameters changes in the sensitivity analyses.ConclusionA national immunization strategy based in Switch-to PCV13 was found to be good value for money and prevent additional burden of pneumococcal disease saving additional treatment costs, when compared with to Keep-PCV10 in Colombia, however additional criteria to decision making must be taken into account.     

Effect of prior vaccination on carriage rates of Streptococcus pneumoniae in older adults: A longitudinal surveillance study

IntroductionPneumococcus is a commensal of the upper respiratory tract and colonization is common in young children. Carriage studies have provided insights on vaccine effects in children and may also be useful for assessing vaccines in adults. However, culture based prevalence studies in older adults describe low colonization rates. Therefore, we assessed cumulative incidence of pneumococcal colonization in older adults using polymerase chain reaction (PCR) targeting the lytA gene and risk factors for carriage.Methods100 community-dwelling adults ≥65 years were enrolled the winter of 2015 and followed biweekly for 12 months. Medical, vaccination and illness history as well as nasopharyngeal (NP) and oropharyngeal (OP) samples were collected. Combined OP and NP were incubated in enrichment broth and screened using real-time lytA PCR. Samples from new colonization events (lytA PCR+) were cultured on gentamicin blood agar plates. Isolates identified by colony morphology as S. pneumoniae were serotyped using a multiplex combined immunoassay-PCR platform which classifies 96 serotypes. Cumulative incidence of pneumococcal carriage was calculated and risk factors for carriage assessed.ResultsThe cumulative incidence of colonization was 41% by PCR and 14% by culture. Monthly prevalence ranged from 0 to 17% by PCR and 1 to 4% by culture with peaks in the spring and fall. Demographics were similar between colonized and never colonized subjects although colonized were younger (72.4 vs. 75.0 years, P = 0.06). Vaccination with any pneumococcal vaccine before or during study period was associated with decreased risk of becoming colonized (p < 0.001) as was vaccination with either the 13-valent conjugated pneumococcal vaccine (PCV13) or 23-valent polysaccharide vaccine (PPSV23) (p < 0.001).ConclusionPneumococcal colonization in older adults as detected by lytA PCR is frequent and pneumococcal vaccination appears to be associated with decreased risk of carriage. Further study is needed to understand the biological significance of molecular detection of pneumococcus in adults.     

Reduced serologic sensitivity to influenza A virus illness among inactivated influenza vaccinees

We compared ≥4-fold increases in antibody titers by hemagglutination inhibition assay to RT-PCR results among 42 adults with PCR-confirmed influenza A virus illnesses. Serologic sensitivity was higher among unvaccinated (69%, 95% confidence interval [CI] = 48–90%) than vaccinated healthcare personnel (38%, 95% CI = 29–46%) in a 2010–11 prospective cohort.