Regional Disparities in the Uptake of Differentiated Influenza Vaccines in the United States.

Significant racial/ethnic inequities in the uptake of differentiated influenza vaccines (DIVs) have been previously reported, though less is known about regional disparities. We conducted a retrospective longitudinal study (2014/15-2017/18 influenza seasons) among privately insured adults aged 65 + years in the US. The exposure was the beneficiary's area of residence (US Census Bureau division) and the outcome was the type of influenza vaccine: differentiated (high-dose [HDV], adjuvanted, recombinant, and cell-based) versus conventional standard-dose egg-based. Multilevel logistic regression modeling, guided by a causal diagram, was used to assess the influence of socio-demographics, medical, healthcare utilization, community, and vaccinator characteristics in confounding or mediating regional disparities. Among those vaccinated in physician offices, beneficiaries in the East North Central region were twice as likely to receive a DIV vs those in the South Atlantic, whereas those in the East and West South Central were least likely. Disparities became more pronounced in models adjusted for individual and community characteristics, suggesting that crude uptake estimates understate the true magnitude of disparities. A vaccinator's previous HDV use was most influential in explaining regional differences. Similar but less pronounced patterns emerged for vaccinations in pharmacies/facilities. Regional disparities remained even in fully adjusted models, pointing to currently poorly understood factors that may include quality of healthcare, client health literacy and engagement, and other political and cultural factors.

What explains racial/ethnic inequities in the uptake of differentiated influenza vaccines?

We investigated the role of individual, community and vaccinator characteristics in mediating racial/ethnic disparities in the uptake of differentiated influenza vaccines (DIVs; including high-dose, adjuvanted, recombinant and cell-based vaccines). We included privately-insured (commercial and Medicare Advantage) ≥65 years-old community-dwelling health plan beneficiaries in the US with >1 year of continuous coverage and who received ≥1 influenza vaccine during the study period (July 2014-June 2018). Of 2.8 million distinct vaccination claims, 60% were for DIVs; lower if received in physician offices (49%) compared to pharmacies/facilities (74%). Among those vaccinated in physician offices, non-whites had lower odds of receiving a DIV if they lived in a non-minority county (0.77;95%CI 0.75-0.80) and even lower odds if they lived in a minority county (0.62;0.60-0.63). Differences in education, household income, medical history, community and vaccinator characteristics did not fully explain the disparities. Similar patterns emerged for vaccinations in pharmacies/facilities, although disparities disappeared altogether after controlling for socio-economic and vaccinator characteristics. When vaccinated in physician offices, minority county residents were less likely to receive a DIV, especially for non-whites (0.72;0.67-0.78). These disparities disappeared for whites, but not for non-whites, after controlling for community and vaccinator characteristics. We found an alarming level of inequity in DIV vaccine uptake among fully insured older adults that could not be fully explained by differences in sociodemographic, medical, community, and vaccinator characteristics. New strategies are urgently needed to address these inequities.

Vaccine coverage among children with epilepsy in two Canadian provinces: A Canadian immunization research network study.

OBJECTIVES: Children with epilepsy are at increased risk of complications from vaccine-preventable infections, yet information on vaccine coverage in these children is scarce. We aimed to compare vaccine coverage among children with epilepsy to children without epilepsy. STUDY DESIGN: We conducted a retrospective cohort study including all 2005-2013 births in Manitoba and Ontario, Canada, creating two cohorts: 2-year-olds and 7-year-olds (followed to age 2 and 7 years). We split each cohort into epilepsy and non-epilepsy subcohorts. We assessed vaccination coverage based on provincial schedules and determined timeliness of MMR (measles, mumps, rubella) dose 1 (recommended at 12 months) and DTaP (diphtheria, tetanus, pertussis) dose 4 (recommended at 18 months). We used logistic regression to calculate adjusted odds ratios (aORs) of the association between epilepsy and vaccination, combining both provincial estimates using random effects meta-analysis. RESULTS: We included 16,558 2-year-olds (Manitoba, 653; Ontario, 15,905) and 13,004 7-year-olds (Manitoba, 483; Ontario, 12,521) with epilepsy. At age 2 years, the aOR for up-to-date vaccination among children with versus without epilepsy was 0.9 (95% confidence interval 0.8-1.1); at age 7 years it was 1.0 (0.9-1.1). Infants diagnosed with epilepsy before age 6 months were less likely to be up-to-date at age 2 years (0.9; 0.8-0.9), although this difference disappeared by age 7 years. Vaccine timeliness was similar between children with and without epilepsy for MMR dose 1 and DTaP dose 4. CONCLUSIONS: Overall, this study suggests that children with epilepsy are not significantly under-vaccinated compared to their peers without epilepsy. As children with epilepsy are at a higher risk of complications from vaccine-preventable diseases, vaccination in children with epilepsy should be optimized, especially early in life, as these children may not be able to rely on herd protection.

Adverse Events Following Immunization Among Children With Epilepsy: A Self-Controlled Case Series.

BACKGROUND: In children with epilepsy, fever and illness are known triggers for seizure; therefore, clinicians and parents could be concerned that immunization-induced inflammation and fever could also trigger seizures. We sought to estimate the risk of emergency department (ED) visit or hospitalization for epilepsy/seizure and all causes after immunization in children younger than 7 years of age with epilepsy. METHODS: We conducted a self-controlled case series of children diagnosed with epilepsy before their 7th birthday and immunized from 2005 to 2015 in Ontario (population 14.2 million) and Manitoba (population 1.3 million), Canada, using administrative healthcare data. We estimated the age- and season-adjusted relative incidence (aRI) of epilepsy/seizure-related and all-cause ED visits/hospitalizations during various risk periods 0-28 days after inactivated and live immunizations versus a control period 35-83 days postimmunization. Estimates from each province were analyzed separately and then combined in a random-effects meta-analysis. RESULTS: The combined risk of epilepsy/seizure-related hospitalization/ED visit was increased 0-2 days after inactivated vaccines (aRI = 1.5, 95% confidence interval: 1.1-1.9) and 7-10 days after live vaccines (aRI = 1.9, 1.4-2.7). For all-cause ED visit/hospitalization, the combined aRI estimate was 0.9 (0.8-1.2) 0-2 days after inactivated vaccines and 1.3 (1.1-1.5) 7-10 days after live vaccines. CONCLUSIONS: The risk of epilepsy/seizure-related ED visit/hospitalization was modestly increased among children with epilepsy during peak periods of fever and inflammation following inactivated and live vaccines. These risks must be balanced against the risk of complications from vaccine-preventable diseases.

The Direct Medical Costs of Diseases Associated with Human Papillomavirus Infection in Manitoba, Canada.

BACKGROUND: The total direct cost of screening and treating all human papillomavirus-related diseases (HPV-RD) has not been measured in a single study. Accurate cost estimates are needed to inform decisions on intervention priorities and evaluate the cost-effectiveness of existing programs. We used province-wide clinical, administrative, and accounting databases to measure direct medical costs of HPV infection in Manitoba (Canada). METHODS: All persons 9 years or older with health insurance coverage in Manitoba between April 2000 and March 2015 were eligible. We identified all persons with an incident HPV-RD and aggregated all medical costs (in 2014 Canadian dollars) related to that condition, including prescription drugs, diagnostic procedures, in-hospital and outpatient treatment, and physician visits. RESULTS: We found that the median cost of treating a case of anogenital warts was $130. An episode of cervical dysplasia had a median cost of $220, compared to $1300 for an episode of cervical carcinoma in situ. The cost of treating HPV-related invasive cancer varied from $15,000 for cervical cancer to $33,000 for oral cavity cancer. Overall, 80% ($145 million) of the total cost was attributable to HPV infection. Cervical screening and follow-up accounted for $96 million (66%) of all costs and this cost component has declined following the introduction of new screening guidelines. CONCLUSIONS: Overall, the average direct medical cost of HPV infection was $720 per newborn. The economic burden of HPV remains significant, although changes in cervical screening guidelines, prompted by the introduction of a public HPV vaccine program, appear to have promoted a promising trend towards lower costs.

Long-term trends in invasive pneumococcal disease in Manitoba, Canada.

Invasive pneumococcal disease (IPD) remains a significant public health problem in Manitoba, Canada although publically-funded pneumococcal conjugate (PCV7 and PCV13) and polysaccharide (PPV23) vaccination programs exist. We analyzed routine surveillance and administrative health data to examine trends in IPD rates as these vaccines were introduced. Data on all individuals with a laboratory-confirmed diagnosis of IPD between 2001 and 2014 were obtained from the provincial Communicable Diseases Surveillance database and linked with Manitoba's provincial immunization registry and physician and hospital databases. We calculated IPD incidence rates overall, by serotype and for different population subgroups defined by socio-demographic and clinical (e.g., chronic diseases, immune status) characteristics. Annual IPD incidence (95%CI) was 8.6 (8.2-9.1)/100,000 people during the study period (n = 1092), and rates were higher in recent years and in regions with predominately indigenous populations. Reduction in the incidence of serotypes included in PCV7 have been offset by rising rates of PCV13-only serotypes in children, and more recently by rising rates of PPV-only serotypes and non-vaccine serotypes among young children and older adults (≥ 65 years). Rates were 3 times higher in those with a chronic disease and highest (> 175-fold) among alcoholics, organ-transplant, and chronic kidney failure patients. The case fatality rate was 12.0% within 30 d of diagnosis. Despite the introduction of several vaccination programs, overall rates of IPD have not declined in Manitoba in the last decade, due to increase in incidence of non-PCV7 serotypes. A disproportionately high burden of disease impacts indigenous communities and people with chronic disease.