H1N1: a Mexican perspective.

In April this year, a new influenza virus of swine origin emerged in Mexico and spread rapidly around the world. As the Northern hemisphere winter flu season kicks off, Laura Vargas-Parada reports on the measures that Mexico is taking to combat the H1N1 pandemic.

Pivoting From Influenza to COVID-19 Vaccinations: How a Minnesota Vaccination Program Reduced Barriers for Refugee, Immigrant, and Migrant Communities Accessing Vaccines During the COVID-19 Pandemic.

The Minnesota Immunization Networking Initiative (MINI) led by Fairview Health Services has addressed barriers to accessing immunizations through partnerships with community organizations to provide free influenza vaccinations to historically underserved communities, especially refugee, immigrant, and migrant communities. Once the COVID-19 vaccine was available, MINI quickly pivoted operations to distribute the vaccine and provide technical assistance to community partners amidst rapidly evolving guidance. With infrastructure and a vaccination team in place, MINI responded to new and emerging needs, eg, implementing a more accessible and low-tech scheduling system, increasing staffing to meet growing needs, and expanding partnerships with community organizations and leaders. From February 2021 to September 2023, MINI organized 1120 community-based vaccine clinics and administered 43,123 COVID-19 vaccinations. Of those vaccine recipients, 88% identified as Black, Indigenous, and other people of color, and for preferred language, over half stated that they preferred a language other than English. These demographics are similar to those of the earlier influenza clinics, even as average annual clinics have tripled and average total vaccinations have quadrupled since the pivot to COVID-19 vaccination clinics. Some keys to success were: (1) consistent, bidirectional communication and shared decision-making with community partners; (2) prioritizing sustainable staffing models with the support of administrative leadership and resources; and (3) having a community-informed approach supported by the practice of hiring staff from communities served. Because of the effectiveness of this model, MINI is primed to respond to planned and unplanned emergent public health crises.

Virological and Epidemiological Situation in the Influenza Epidemic Seasons 2016/2017 and 2017/2018 in Poland.

The World Health Organization estimates that influenza virus infects 3-5 million people worldwide every year, of whom 290,000 to 650,000 die. In the 2016/2017 epidemic season in Poland, the incidence of influenza was 1,692 per 100,000 population. The influenza A virus, subtype A/H3N2/, was the predominant one in that season. However, in the most recent 2017/2018 epidemic season, the incidence exceeded 1,782 per 100,000 already by August of 2018. In this season, influenza B virus predominated, while the A/H1N1/pdm09 strain was most frequent among the influenza A subtypes. The peak incidence, based on the number of clinical specimens tested, was in weeks 4-5 of 2017 and week 8 of 2018 in the 2016/2017 and 2017/2018 epidemic seasons, respectively. As of the 2017/2018 season, a quadrivalent vaccine, consisting of two antigens of influenza A subtypes and another two of influenza B virus, was available in Poland. Nonetheless, the vaccination rate remained at one of the lowest level in Europe, fluctuating between 3% and 4% of the general Polish population.

Prioritising access to pandemic influenza vaccine: a review of the ethics literature.

BACKGROUND: The world is threatened by future pandemics. Vaccines can play a key role in preventing harm, but there will inevitably be shortages because there is no possibility of advance stockpiling. We therefore need some method of prioritising access. MAIN TEXT: This paper reports a critical interpretative review of the published literature that discusses ethical arguments used to justify how we could prioritise vaccine during an influenza pandemic. We found that the focus of the literature was often on proposing different groups as priorities (e.g. those with pre-existing health conditions, the young, the old, health care workers etc.). Different reasons were often suggested as a means of justifying such priority groupings (e.g. appeal to best overall outcomes, fairness, belonging to a vulnerable or 'at risk' group etc.). We suggest that much of the literature, wrongly, assumes that we are able to plan priority groups prior to the time of a particular pandemic and development of a particular vaccine. We also point out the surprising absence of various issues from the literature (e.g. how vaccines fit within overall pandemic planning, a lack of specificity about place, issues of global justice etc.). CONCLUSIONS: The literature proposes a wide range of ways to prioritise vaccines, focusing on different groups and 'principles'. Any plan to use pandemic vaccine must provide justifications for its prioritisation. The focus of this review was influenza pandemic vaccines, but lessons can be learnt for future allocations of coronavirus vaccine, if one becomes available.

[Vaccination in Mexico: imprecise coverages and deficiency in the follow-up of children with incomplete immunization]. / Vacunación en México: coberturas imprecisas y deficiencia en el seguimiento de los niños que no completan el esquema.

OBJECTIVE: To analyze the validity of the official vaccination figures according to the available information and to identify opportunities for improvement. MATERIALS AND METHODS: We estimated vaccination coverage and dropout rates (for multi-dose vaccines) for one-year-old children, based on public information from the dynamic cubes of the Ministry of Health, for the years 2015 to 2017. R. RESULTS: We observed variations in the vaccination monthly reports, which indicate low rates of vaccination, as well as high dropout rates when comparing first and third doses applied. For children 1 year of age, the national complete coverage was estimated at 48.9. CONCLUSIONS: There is no reliable information to estimate the actual vaccination coverage. Government documents report a constant overestimation of vaccination coverage that creates a "false sense of security". This has become a barrier for the critical analysis of the Universal Vaccination Program.

OBJETIVO: Analizar la veracidad de las cifras oficiales de acuerdo con la información disponible e identificar oportunidades de mejora. MATERIAL Y MÉTODOS: Estimamos las coberturas de vacunación y tasas de deserción (para las vacunas administradas en multidosis) del esquema básico para niños menores de un año de edad, con base en la información de cubos dinámicos de la Secretaría de Salud de 2015 a 2017. RESULTADOS: Observamos variaciones en los reportes mensuales de vacunación que indican bajas tasas de vacunación, así como índices altos de deserción al comparar primeras y terceras dosis aplicadas. La cobertura nacional de esquema completo se estimó en 48.9 por ciento. CONCLUSIONES: No se cuenta con información confiable que permita estimar las coberturas reales de vacunación. En los reportes oficiales hay una constante sobrestimación de las coberturas que ha creado a una "falsa sensación de seguridad". Esto se ha constituido en una barrera que impide el análisis crítico del Programa Universal de Vacunación.

Stockpiled Avian Influenza A(H7N9) Vaccines Induce Robust, Nonneutralizing Functional Antibodies Against Antigenically Drifted Fifth-Wave A(H7N9) Viruses.

Human infections caused by avian influenza A(H7N9) viruses have raised concerns of a pandemic. The capability of the current stockpiled A(H7N9) vaccines to induce cross-protective, nonneutralizing functional antibodies against antigenically drifted A(H7N9) viruses has not been evaluated before. Here we show that vaccination with either MF59- or AS03-adjuvanted inactivated A(H7N9) vaccines elicited robust, cross-reactive antibody-dependent cell-mediated cytotoxicity-mediating and neuraminidase-inhibiting functional antibodies against the antigenically drifted A(H7N9) viruses that emerged recently during the fifth-wave outbreak in China, including a highly pathogenic A(H7N9) human isolate. Such cross-reactive humoral immunity may provide vital first-line defense against fatal outcomes in case of an A(H7N9) pandemic.

The PanVax Tool to Improve Pandemic Influenza Emergency Vaccination Program Readiness and Partnership.

Objectives. To show how the Centers for Disease Control and Prevention's Pandemic Vaccine Campaign Planning Tool (PanVax Tool) can help state and local public health emergency planners demonstrate and quantify how partnerships with community vaccine providers can improve their overall pandemic vaccination program readiness.Methods. The PanVax Tool helps planners compare different strategies to vaccinate their jurisdiction's population in a severe pandemic by allowing users to customize the underlying model inputs in real time, including their jurisdiction's size, community vaccine provider types, and how they allocate vaccine to these providers. In this report, we used a case study with hypothetical data to illustrate how jurisdictions can utilize the PanVax Tool for preparedness planning.Results. By using the tool, planners are able to understand the impact of engaging with different vaccine providers in a vaccination campaign.Conclusions. The PanVax Tool is a useful tool to help demonstrate the impact of community vaccine provider partnerships on pandemic vaccination readiness and identify areas for improved partnerships for pandemic response.

Influenza vaccine: A viable option to protect pregnant women and infants from seasonal flu: A retrospective hospital-based study in India.

BACKGROUND: Influenza is a highly contagious disease with global annual outbreaks of 3-5 million severe cases and 0.25-0.5 million deaths. The risk is greater in pregnant women that results in high morbidity and mortality. OBJECTIVE: The objective of this study was to see the efficacy of influenza vaccine on pregnant women and their newborn upto 6 months. METHOD: This was a retrospective study (January 2016-March 2018). Records of 346 pregnant women were included in this study (vaccinated: 288; unvaccinated: 58). Women and infants were categorised into Category A, B or C according to the guidelines issued by the Ministry of Health and Family Welfare, India on influenza. RESULTS: The groups were comparable with respect to baseline characteristics. Greater number of women received influenza vaccine during the first trimester (n = 117). During the gestation period, majority of the women in the vaccinated group were symptom-free compared with the unvaccinated (92% vs 70.7%). Also, none of the vaccinated women were categorised into category C compared with one who was laboratory tested positive for influenza in the unvaccinated group. Similar results were seen postpartum and more number of infants remained symptom-free in the vaccinated group compared with unvaccinated (69.3% vs 25.9%). More number of infants were born pre-term in the unvaccinated group compared with vaccinated (15.5% vs 8.6%). CONCLUSIONS: Immunisation with influenza vaccine in any trimester during pregnancy was found to protect the mother and infants upto 6 months of age against seasonal influenza without significant maternal adverse effects. In order to improve vaccination rates, there must be a national vaccination policy and incorporation of maternal immunisation in standard antenatal care.

100 Years of Medical Countermeasures and Pandemic Influenza Preparedness.

The 1918 influenza pandemic spread rapidly around the globe, leading to high mortality and social disruption. The countermeasures available to mitigate the pandemic were limited and relied on nonpharmaceutical interventions. Over the past 100 years, improvements in medical care, influenza vaccines, antiviral medications, community mitigation efforts, diagnosis, and communications have improved pandemic response. A number of gaps remain, including vaccines that are more rapidly manufactured, antiviral drugs that are more effective and available, and better respiratory protective devices.

Antenatal influenza and pertussis vaccine uptake among Aboriginal mothers in Western Australia.

BACKGROUND: Antenatal influenza and pertussis vaccination prevent serious disease in mothers and infants. Aboriginal individuals are at increased risk of infection yet little is known about vaccine coverage among Aboriginal mothers. AIMS: To estimate the uptake of influenza and pertussis vaccination among pregnant Aboriginal women in Western Australia and identify barriers and enablers to vaccination. MATERIALS AND METHODS: Four hundred Aboriginal women, aged ≥18 years, who gave birth to a live infant between April and October 2015, were randomly selected and invited to participate in telephone interviews. Of the 387 women who did not decline, 178 had a functioning phone number and 100 completed the survey. Analyses were weighted by maternal residence. RESULTS: During pregnancy the majority of Aboriginal mothers were recommended influenza (66%; unweighted, 65/96 = 68%) and pertussis (65%; unweighted, 62/94 = 66%) vaccines, with 62% (unweighted, 56/94 = 56%) and 63% (unweighted, 60/93 = 65%) receiving the vaccinations, respectively. Almost all vaccinated women (98%) reported wanting to protect their baby as the reason for immunisation. Rural mothers were more likely than metropolitan mothers to have been vaccinated against influenza (odds ratio (OR) 4.1, 95% CI 1.7-10.2) and pertussis (OR 3.1, 95% CI 1.2-7.6). Recommendation by a healthcare provider was strongly associated with vaccine uptake (influenza: OR 15.6, 95% CI 4.9-49.5; pertussis: OR 13.3, 95% CI 4.6-38.0). CONCLUSION: Vaccination uptake among Western Australian Aboriginal mothers is comparable with rates reported for non-Aboriginal populations worldwide. Provider recommendation is the single most important factor associated with vaccination uptake, underlining the importance of integrating vaccination into routine antenatal care.

Quantifying and explaining accessibility with application to the 2009 H1N1 vaccination campaign.

Accessibility and equity across populations are important measures in public health. This paper is specifically concerned with potential spatial accessibility, or the opportunity to receive care as moderated by geographic factors, and with horizontal equity, or fairness across populations regardless of need. Both accessibility and equity were goals of the 2009 vaccination campaign for the novel H1N1a influenza virus, including during the period when demand for vaccine exceeded supply. Distribution system design can influence equity and accessibility at the local level. We develop a general methodology that integrates optimization, game theory, and spatial statistics to measure potential spatial accessibility across a network, where we quantify spatial accessibility by travel distance and scarcity. We estimate and make inference on local (census-tract level) associations between accessibility and geographic, socioeconomic, and health care infrastructure factors to identify potential inequities in vaccine accessibility during the 2009 H1N1 vaccination campaign in the U.S. We find that there were inequities in access to vaccine at the local level and that these were associated with factors including population density and health care infrastructure. Our methodology for measuring and explaining accessibility leads to policy recommendations for federal, state, and local public health officials. The spatial-specific results inform the development of equitable distribution plans for future public health efforts.

Lessons from a pandemic.

It is time to assess what worked, and what didn't, in the global efforts to cope with swine flu.

Available influenza vaccines: immunization strategies, history and new tools for fighting the disease.

The main public health strategy for containing influenza-related disease is annual vaccination, which is recommended for the elderly and others belonging to risk-factor categories, who present the highest morbidity and mortality, as reported by the World Health Organization (WHO) Recommendations. The availability of different influenza vaccine formulations makes the choice of the best immunization strategy a challenge for stakeholders and public health experts. Heterogeneity in at-risk categories included in national influenza vaccine recommendations still exists, in particular among European countries. Broader consensus is expected, which should positively impact on influenza vaccination coverage. The availability of quadrivalent vaccines, containing both influenza B lineages, offers the potential to improve protection by overcoming the drawbacks of wrongly predicting which B lineage will predominate in a given year.

Introduction of a quadrivalent influenza vaccine in Italy: a budget impact analysis.

Every year in Italy, the Ministry of Health (MoH) offers influenza vaccination free of charge to all subjects at risk and to all subjects aged ≥ 65 year old. Until 2014-2015 immunization campaign against Trivalent Influenza Vaccine (TIVs) were the only vaccines used in Italy. Traditional TIVs contain antigens from three viral strains: A(H1N1), A(H3N2), and one of the two B lineages: B(Victoria) or B(Yamagata). Each year, the World Health Organization (WHO) decides which viral strains should be included in the next seasonal influenza vaccine. However, accurately predicting which B-lineage strain will predominate in the upcoming season has proved to be a challenging task, owing to the co-circulation of both lineages. To address the issue of B-mismatch, a new Quadrivalent Influenza Vaccine (QIV) containing both B-lineage strains has been developed, in order to achieve broader protection against influenza. The new QIV was approved in Italy in 2015 and included by the MoH in the national recommendations for the seasonal immunization campaign against influenza 2015-2016. Recently, a Health Technology Assessment (HTA) Report has shown that, in comparison with TIVs, the new QIV is cost-effective (Incremental Cost-Effectiveness Ratio (ICER) = € 18,883/ (QALY) Quality-Adjusted Life-Year) from the Italian National Health Service (NHS) perspective. The present Budget Impact Analysis (BIA) showed that the introduction of the QIV with a 9% market share in the vaccine mix for the 2015-2016 flu campaign would yield an annual saving of € 674,089, mainly owing to the broader protection offered by QIV vs TIVs with an estimated 49.12% B-mismatch.

On the optimal production capacity for influenza vaccine.

This paper analyzes the profit maximizing capacity choice of a monopolistic vaccine producer facing the uncertain event of a pandemic in a homogenous population of forward-looking individuals. For any capacity level, the monopolist solves the intertemporal price discrimination problem within the dynamic setting generated by the standard mathematical epidemiological model of infectious diseases. Even though consumers are assumed to be identical, the monopolist will be able to exploit the ex post heterogeneity between infected and susceptible individuals by raising the price of vaccine in response to the increasing hazard rate. The monopolist thus bases its investment decision on the expected profits from the optimal price path given the infection dynamics. It is shown that the monopolist will always choose to invest in a lower production capacity than the social planner. Through numerical simulation, it is demonstrated how the loss to society of having a monopoly producer decreases with the speed of infection transmission. Moreover, it is illustrated how the monopolist's optimal vaccination rate increases as its discount rate rises for cost parameters based on Swedish data. However, the effect of the firm discount rate on its investment decision is sensitive to assumptions regarding the cost of production capacity.