Survey of Physician Practices, Attitudes, and Knowledge Regarding Recombinant Zoster Vaccine.

BACKGROUND: Herpes zoster vaccination rates remain low despite longstanding national recommendations to vaccinate immunocompetent adults aged ≥ 50 years. The Advisory Committee on Immunization Practice (ACIP) updated its recommendations for recombinant zoster vaccine (RZV) in October 2021 to include immunocompromised adults aged ≥19 years. OBJECTIVE: To assess practices, attitudes, and knowledge about RZV, barriers to recommending RZV, and likelihood of recommending RZV to patients with various immunocompromising conditions. DESIGN: Mail and internet-based survey conducted from May through July 2020. PARTICIPANTS: General internists and family physicians throughout the USA. MAIN MEASURES: Survey responses. KEY RESULTS: The response rate was 66% (632/955). Many physicians were already recommending RZV to immunocompromised populations, including adults ≥50 years with HIV (67% of respondents) and on recombinant human immune modulator therapy (56%). Forty-seven percent of respondents both stocked/administered RZV and referred patients elsewhere, frequently a pharmacy, for vaccination; 42% did not stock RZV and only referred patients. The majority agreed pharmacies do not inform them when RZV has been given (64%). Physicians were generally knowledgeable about RZV; however, 25% incorrectly thought experiencing side effects from the first dose of RZV that interfere with normal activities was a reason to not receive the second dose. The top reported barrier to recommending RZV was experience with patients declining RZV due to cost concerns (67%). Most physicians reported they would be likely to recommend RZV to immunocompromised patients. CONCLUSION: Most primary care physicians welcome updated ACIP RZV recommendations for immunocompromised adults. Knowledge gaps, communication issues, and financial barriers need to be addressed to optimize vaccination delivery.

Cost-Effectiveness Analysis of Vaccination With Recombinant Zoster Vaccine Among Hematopoietic Cell Transplant Recipients and Persons With Other Immunocompromising Conditions Aged 19 to 49 Years.

OBJECTIVES: This study aimed to estimate the cost-effectiveness of the use of recombinant zoster vaccine (RZV) (Shingrix), which protects against herpes zoster (HZ), among immunocompromised adults aged 19 to 49 years, as a contribution to deliberations of the Advisory Committee on Immunization Practices. METHODS: Hematopoietic cell transplant (HCT) recipients experience a high incidence of HZ, and the efficacy of RZV in preventing HZ has been studied in clinical trials. The cost-effectiveness model calculated incremental cost-effectiveness ratios that compared vaccination with RZV with a no vaccination strategy among adults aged 19 to 49 years. Costs and outcomes were calculated until age 50 years using the healthcare sector perspective and summarized as cost per quality-adjusted life-year (QALY) gained. The base case represents HCT recipients, with scenario analyses representing persons with other immunocompromising conditions, including hematologic malignancies, human immunodeficiency virus, and autoimmune and inflammatory conditions. Uncertainty was investigated using univariate, multivariate, and probabilistic sensitivity analyses. RESULTS: Base-case results indicated vaccination with RZV would avert approximately 35% of HZ episodes and complications, while saving approximately 11% of net costs. Compared with no vaccination, vaccination of HCT recipients with RZV generated cost-savings (ie, lower costs and improved health) in the base case and in 81% of simulations in the probabilistic analysis. In scenario analyses, vaccination cost US dollar ($) 9500/QALY among patients with hematologic malignancies, $79 000/QALY among persons living with human immunodeficiency virus, and $208 000/QALY among persons with selected autoimmune and inflammatory conditions. CONCLUSIONS: Generally favorable economic estimates supported recommendations for vaccination of immunocompromised adults with RZV to prevent episodes of HZ and related complications.

Monitoring Varicella Vaccine Impact on Varicella Incidence in the United States: Surveillance Challenges and Changing Epidemiology, 1995-2019.

Surveillance is critical for monitoring vaccine impact. Varicella surveillance challenges predated varicella vaccine US licensure in 1995. Several interim steps were needed before case-based surveillance could be established in most states, and both active and passive surveillance was needed to document the vaccination program's impact on varicella incidence. By the end of the 1-dose program in 2005, incidence had declined 90% in the active surveillance areas, with significant declines occurring in all age groups within 5 years of program implementation. Additional declines occurred during the 2-dose program leading to >97% decline in incidence over the 25 years of program implementation through 2019, based on data from 4 states with continuous passive reporting. Surveillance showed that declines were highest among children and adolescents covered by the routine vaccination recommendations but occurred in all age groups. Although surveillance systems changed and were adapted to reflect evolving epidemiology, data consistently demonstrated decreasing varicella incidence following the vaccination program implementation. The vaccination program dramatically decreased virus circulation and increased community protection. Continued and improved varicella surveillance is needed to accurately monitor disease epidemiology and further guide prevention efforts.

The Impact of Universal Varicella Vaccination on Herpes Zoster Incidence in the United States: Comparison of Birth Cohorts Preceding and Following Varicella Vaccination Program Launch.

When the US varicella vaccination program was introduced in 1995, its impacts on the epidemiology of herpes zoster (HZ) were not precisely known. We used a large claims database to examine HZ incidence in the US during 1998-2019 among persons aged ≥30 years (the prevaccine cohort, born before 1990), and aged 1-29 years (includes the postvaccine cohort, born since 1990). We defined incident HZ as the first instance of an outpatient or emergency department (ED) claim with an HZ diagnostic code. Additionally, we examined the proportion of HZ visits among all ED visits as a complementary method to assess for healthcare-seeking artifacts in the findings. In persons aged ≥30 years (prevaccine cohort), we observed age-specific increases in HZ incidence during the earlier study years, with decelerations in later years, starting in 2007 with oldest age groups. Similar patterns were seen when we examined HZ visits as a proportion of all ED visits. For persons aged 1-29 years, age-specific HZ incidence increased early in the study period for the oldest age groups who were born prevaccine, but later declined in a stepwise pattern once each age group was comprised of persons born in the postvaccine period. Our results, corroborated with previously published studies, do not support prior modeling predictions that the varicella vaccination program would increase HZ incidence among adult cohorts who previously experienced varicella. Our findings also suggest that continued declines in age-specific HZ incidence as varicella-vaccinated cohorts age are likely.

Health and Economic Impact of the United States Varicella Vaccination Program, 1996-2020.

BACKGROUND: The aim of this study was to evaluate the health and economic impact of the varicella vaccination program on varicella disease in the United States (US), 1996-2020. METHODS: Analysis was conducted using the Centers for Disease Control and Prevention or published annual population-based varicella incidence, and varicella-associated hospitalization, outpatient visit, and mortality rates in the US population aged 0-49 years during 1996-2020 (range, 199.5-214.2 million persons) compared to before vaccination (1990-1994). Disease costs were estimated using the societal perspective. Vaccination program costs included costs of vaccine, administration, postvaccination adverse events, and travel and work time lost to obtain vaccination. All costs were adjusted to 2020 US dollars using a 3% annual discount rate. The main outcome measures were the number of varicella-associated cases, hospitalizations, hospitalization days, and premature deaths prevented; life-years saved; and net societal savings from the US varicella vaccination program. RESULTS: Among US persons aged 0-49 years, during 1996-2020, it is estimated that more than 91 million varicella cases, 238 000 hospitalizations, 1.1 million hospitalization days, and almost 2000 deaths were prevented and 118 000 life-years were saved by the varicella vaccination program, at net societal savings of $23.4 billion. CONCLUSIONS: Varicella vaccination has resulted in substantial disease prevention and societal savings for the US over 25 years of program implementation.

Use of Recombinant Zoster Vaccine in Immunocompromised Adults Aged ≥19 Years: Recommendations of the Advisory Committee on Immunization Practices - United States, 2022.

Zoster Vaccine Recombinant, Adjuvanted (Shingrix, GlaxoSmithKline [GSK]) is a 2-dose (0.5 mL each) subunit vaccine containing recombinant glycoprotein E in combination with adjuvant (AS01B) that was licensed in the United States for prevention of herpes zoster for adults aged ≥50 years by the Food and Drug Administration (FDA) and recommended for immunocompetent adults aged ≥50 years by the Advisory Committee on Immunization Practices (ACIP) in 2017* (1). On July 23, 2021, the FDA expanded the indication for recombinant zoster vaccine (RZV) to include adults aged ≥18 years who are or will be at increased risk for herpes zoster because of immunodeficiency or immunosuppression caused by known disease or therapy (2). On October 20, 2021, ACIP recommended 2 doses of RZV for the prevention of herpes zoster and related complications in adults aged ≥19 years† who are or will be immunodeficient or immunosuppressed because of disease or therapy. RZV is the first herpes zoster vaccine approved for use in immunocompromised persons. With moderate to high vaccine efficacy and an acceptable safety profile, RZV has the potential to prevent considerable herpes zoster incidence and related complications. This report updates previous ACIP recommendations for the prevention of herpes zoster (1,3).

Interim Recommendation of the Advisory Committee on Immunization Practices for Use of the Novavax COVID-19 Vaccine in Persons Aged ≥18 years - United States, July 2022.

The NVX-CoV2373 (Novavax) COVID-19 vaccine is a recombinant spike (rS) protein nanoparticle vaccine with Matrix-M adjuvant to protect against infection with SARS-CoV-2, the virus that causes COVID-19. On July 13, 2022, the Food and Drug Administration (FDA) issued Emergency Use Authorization (EUA) for the Novavax vaccine for primary COVID-19 immunization of unvaccinated adults aged ≥18 years, administered as 2 doses (5 µg rS and 50 µg Matrix-M adjuvant in each dose) 3 weeks apart (1). On July 19, 2022, the Advisory Committee on Immunization Practices (ACIP) issued an interim recommendation for use of the Novavax vaccine in persons aged ≥18 years for the prevention of COVID-19.* In the per-protocol† efficacy analysis, vaccine efficacy (VE) against reverse transcription-polymerase chain reaction (RT-PCR)-confirmed symptomatic COVID-19 was 89.6% (95% CI = 82.4%-93.8%). The Alpha variant (B.1.1.7) of SARS-CoV-2 was the predominant circulating variant during the period of case accrual for VE assessments. Cases of myocarditis or pericarditis were reported in temporal association with vaccination, suggesting a possible causal relationship. The ACIP recommendation for the use of the Novavax COVID-19 vaccine is interim and will be updated as additional information becomes available. The adjuvanted, protein subunit-based Novavax COVID-19 vaccine provides an additional option for unvaccinated adults, increasing flexibility for the public and for vaccine providers. Vaccination is important for protection against COVID-19.

Interim Recommendations of the Advisory Committee on Immunization Practices for Use of Moderna and Pfizer-BioNTech COVID-19 Vaccines in Children Aged 6 Months-5 Years - United States, June 2022.

On June 17, 2022, the Food and Drug Administration (FDA) issued Emergency Use Authorization (EUA) amendments for the mRNA-1273 (Moderna) COVID-19 vaccine for use in children aged 6 months-5 years, administered as 2 doses (25 µg [0.25 mL] each), 4 weeks apart, and BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine for use in children aged 6 months-4 years, administered as 3 doses (3 µg [0.2 mL] each), at intervals of 3 weeks between doses 1 and 2 and ≥8 weeks between doses 2 and 3. On June 18, 2022, the Advisory Committee on Immunization Practices (ACIP) issued separate interim recommendations for use of the Moderna COVID-19 vaccine in children aged 6 months-5 years and the Pfizer-BioNTech COVID-19 vaccine in children aged 6 months-4 years for the prevention of COVID-19.* Both the Moderna and Pfizer-BioNTech COVID-19 vaccines met the criteria for immunobridging, which is the comparison of neutralizing antibody levels postvaccination in young children with those in young adults in whom efficacy had been demonstrated. Descriptive efficacy analyses were also conducted for both Moderna and Pfizer-BioNTech COVID-19 vaccines during the period when the Omicron variant of SARS-CoV-2 (the virus that causes COVID-19) predominated. No specific safety concerns were identified among recipients of either vaccine. ACIP recommendations for the use of the Moderna COVID-19 vaccine and the Pfizer-BioNTech COVID-19 vaccine in children aged 6 months-5 years and 6 months-4 years, respectively, are interim and will be updated as additional information becomes available. Vaccination is important for protecting children aged 6 months-5 years against COVID-19.

Persons Evaluated for 2019 Novel Coronavirus - United States, January 2020.

In December 2019, a cluster of cases of pneumonia emerged in Wuhan City in central China's Hubei Province. Genetic sequencing of isolates obtained from patients with pneumonia identified a novel coronavirus (2019-nCoV) as the etiology (1). As of February 4, 2020, approximately 20,000 confirmed cases had been identified in China and an additional 159 confirmed cases in 23 other countries, including 11 in the United States (2,3). On January 17, CDC and the U.S. Department of Homeland Security's Customs and Border Protection began health screenings at U.S. airports to identify ill travelers returning from Wuhan City (4). CDC activated its Emergency Operations Center on January 21 and formalized a process for inquiries regarding persons suspected of having 2019-nCoV infection (2). As of January 31, 2020, CDC had responded to clinical inquiries from public health officials and health care providers to assist in evaluating approximately 650 persons thought to be at risk for 2019-nCoV infection. Guided by CDC criteria for the evaluation of persons under investigation (PUIs) (5), 210 symptomatic persons were tested for 2019-nCoV; among these persons, 148 (70%) had travel-related risk only, 42 (20%) had close contact with an ill laboratory-confirmed 2019-nCoV patient or PUI, and 18 (9%) had both travel- and contact-related risks. Eleven of these persons had laboratory-confirmed 2019-nCoV infection. Recognizing persons at risk for 2019-nCoV is critical to identifying cases and preventing further transmission. Health care providers should remain vigilant and adhere to recommended infection prevention and control practices when evaluating patients for possible 2019-nCoV infection (6). Providers should consult with their local and state health departments when assessing not only ill travelers from 2019-nCoV-affected countries but also ill persons who have been in close contact with patients with laboratory-confirmed 2019-nCoV infection in the United States.

Outbreaks of Human Salmonella Infections Associated with Live Poultry, United States, 1990-2014.

Backyard poultry flocks have increased in popularity concurrent with an increase in live poultry-associated salmonellosis (LPAS) outbreaks. Better understanding of practices that contribute to this emerging public health issue is needed. We reviewed outbreak reports to describe the epidemiology of LPAS outbreaks in the United States, examine changes in trends, and inform prevention campaigns. LPAS outbreaks were defined as ≥2 culture-confirmed human Salmonella infections linked to live poultry contact. Outbreak data were obtained through multiple databases and a literature review. During 1990-2014, a total of 53 LPAS outbreaks were documented, involving 2,630 illnesses, 387 hospitalizations, and 5 deaths. Median patient age was 9 years (range <1 to 92 years). Chick and duckling exposure were reported by 85% and 38% of case-patients, respectively. High-risk practices included keeping poultry inside households (46% of case-patients) and kissing birds (13%). Comprehensive One Health strategies are needed to prevent illnesses associated with live poultry.

Recombinant zoster vaccine (RZV) second-dose series completion in adults aged 50-64 years in the United States.

In 2018, CDC recommended a highly efficacious adjuvanted recombinant zoster vaccine (RZV) as a 2-dose series for prevention of herpes zoster (HZ) for immunocompetent persons age ≥ 50 years, with the 2nd dose recommended 2-6 months after the 1st dose. We estimated second-dose RZV series completion in the U.S. among 50-64-year-olds using two administrative databases. Second-dose RZV series completion was ∼70% within 6-months and 80% within 12-months of first dose. Among those who received only 1 RZV dose with at least 12 months of follow-up time, 96% had a missed opportunity for a second-dose vaccination, defined as a provider or pharmacy visit, among whom 36% had a visit for influenza or pneumococcal vaccination within 2-12 months of their first-dose of RZV. We found that RZV series completion rates in 50-64-year-olds was high. Availability of RZV at pharmacies has potentially helped increase series completion, but missed opportunities remain.

Recombinant Zoster Vaccine Uptake and Risk of Flares Among Older Adults With Immune-Mediated Inflammatory Diseases in the US.

OBJECTIVE: Persons with immune-mediated inflammatory diseases (IMIDs) are at an increased risk of herpes zoster (HZ). In 2018, the Centers for Disease Control and Prevention recommended a highly efficacious vaccine, recombinant zoster vaccine (RZV), for prevention of HZ in immunocompetent patients ≥50 years of age. This study was undertaken to estimate RZV vaccination among adults ages ≥50 years with IMIDs during 2018-2019 and to examine possible vaccine-related flares following RZV. METHODS: We identified a cohort of IMID patients using medical claims data from the IBM MarketScan (ages 50-64 years) and Centers for Medicare and Medicaid Services Medicare (ages ≥65 years) databases. Presumed flares were defined as hospitalization/emergency department visit for their respective IMIDs, or steroid treatment with a short-acting oral glucocorticoid or parenteral glucocorticoid injection. We conducted a self-controlled case series (SCCS) analysis to examine a temporal association between RZV and flares. RESULTS: Among enrollees with IMIDs, 14.8% of 55,654 MarketScan enrollees and 43.2% of 160,545 Medicare enrollees received ≥1 dose of RZV in 2018-2019. Two-dose series completion rates were 76.6% in MarketScan enrollees and 85.4% in Medicare enrollees. In the SCCS analysis, 10% and 13% developed flares in the control window, compared to 9% and 11-12% in the risk window following 1 or 2 doses of RZV among MarketScan and Medicare enrollees, respectively. We found no statistically significant increase in flares following RZV administration for any IMID in either age group following RZV dose 1 or dose 2. CONCLUSION: We did not find an increase in presumed flares following RZV vaccination. Among adults ages ≥50 years with IMIDs, a substantial proportion received RZV compared to general zoster coverage estimates, and series completion rates were high.

Projected risks and health benefits of vaccination against herpes zoster and related complications in US adults.

The Advisory Committee on Immunization Practices (ACIP) recommends recombinant zoster vaccine (RZV) to prevent against herpes zoster (HZ) and related complications in immunocompetent adults ≥50 y and immunocompromised adults ≥19 y. In 2019, a statistical safety signal for Guillain-Barré syndrome (GBS) following RZV was identified using data from the Vaccine Safety Datalink (VSD). Subsequently, the U.S. Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and collaborators undertook additional analyses using Centers for Medicare & Medicaid Services (CMS) Medicare data to further investigate the potential risk of GBS following RZV. Concurrently, epidemiologic data suggested a potentially elevated risk of GBS following HZ in U.S. adults. Using data from these sources and a published simulation model, this study evaluated the health benefits and risks associated with vaccinating immunocompetent adults ≥50 y with RZV compared to no vaccination. In the base case analysis, RZV vaccination averted 43,000-63,000 cases of HZ, including GBS complications, per million vaccinated per 10-y age cohort compared to 3-6 additional cases of GBS projected following RZV per million vaccinated in the same population. This analysis highlights the projected health benefits of RZV vaccination compared to the relatively low potential risk of GBS following RZV.

Prevalence of infectious diseases in cats and dogs rescued following Hurricane Katrina.

OBJECTIVE: To determine the prevalence of infectious diseases of animal and zoonotic importance in cats and dogs rescued and transferred from the Gulf Coast region following Hurricane Katrina. DESIGN: Cross-sectional study. ANIMALS: 414 dogs and 56 cats rescued and transferred from the Gulf Coast region within 4 months after the hurricane. PROCEDURES: EDTA-anticoagulated blood and serum samples were tested via PCR and serologic assays for infectious diseases. RESULTS: In dogs, prevalence was highest for anti-West Nile virus (WNV) antibodies (218/390 [55.9%]), Dirofilaria immitis antigen (195/400 [48.8%]), anti-Toxoplasma gondii antibodies (92/366 [25.1%]), and hemotropic mycoplasma DNA (40/345 [11.9%]). The DNA of Bartonella spp, Ehrlichia spp, or Babesia spp or anti-canine influenza virus antibodies were identified in < 2% of dogs. In cats, prevalence was highest for antibodies against Bartonella spp and DNA of Bartonella spp combined (49/55 [89.1 %]), anti-T gondii antibodies (13/55 [23.6%]), hemotropic mycoplasma DNA (5/47 [10.6%]), anti-WNV antibodies (5/48 [10.4%]), D immitis antigen (4/50 [8.0%]), and anti-FIV antibodies (4/56 [7.1%]). A total of 308 (74.4%) dogs and 52 (92.9%) cats had evidence of previous or current vector-borne infections. CONCLUSIONS AND CLINICAL RELEVANCE: Cats and dogs rescued from the disaster region had evidence of multiple infectious diseases. The dispersal of potentially infectious animals to other regions of North America where some infections were not typically found could have contributed to new geographic ranges for these organisms or to underdiagnosis in affected animals because of a low index of suspicion in regions with low disease prevalence.

Risk of Guillain-Barré syndrome following herpes zoster, United States, 2010-2018.

Epidemiologic data regarding the risk of Guillain-Barré syndrome (GBS) following herpes zoster (HZ) are limited. We conducted a self-controlled case series analysis using two large national data sources to evaluate the risk of GBS following HZ among U.S. adults. We analyzed medical claims from the IBM® MarketScan® Commercial Claims and Encounters (persons 18-64 years during 2010-2018) and Centers for Medicare and Medicaid Services Medicare (persons ≥65 years during 2014-2018) databases. HZ cases were defined as persons with an outpatient claim with a primary or secondary ICD-9 or ICD-10 diagnostic code for HZ. GBS cases were defined as persons with an inpatient claim with a principle diagnostic code for GBS and an associated procedural code. We compared the rates of GBS following HZ in the 1-42-day risk window versus primary (100-365-day) or secondary (43-99-day) control windows. We identified 489,516 persons 18-64 years of age and 650,229 persons ≥65 years of age with HZ, among whom 11 and 41, respectively, developed GBS 1-365 days following HZ. The risk of GBS following HZ was increased during the risk window as compared to the primary control window for both groups, with a rate ratio of 6.3 (95% CI, 1.8-21.9) for those 18-64 years and 4.1 (95% CI, 1.9-8.7) for those ≥65 years. This study provides new and methodologically rigorous epidemiologic support for an association between HZ and GBS, and useful context regarding the benefits versus potential risks of zoster vaccination.

Insurance reimbursements for recombinant zoster vaccine in the private sector.

A two-dose series of the recombinant zoster vaccine (RZV, Shingrix) was licensed by the Food and Drug Administration in 2017 and recommended by the Advisory Committee on Immunization Practices in 2018 for adults in the United States age 50 years and older. Despite the health benefits of shingles vaccination, coverage has remained low, with financial barriers among healthcare providers identified as one potential factor. This study estimates the reimbursement levels for RZV among a large sample of privately insured individuals in the US from the 2018 IBM® MarketScan® Commercial Claims and Encounters database. Of 198,534 claims for an RZV dose, the mean reimbursement was $149. Most claims (83%) exceeded $140, which was the private sector vaccine price reported on the CDC vaccine price list in April 2018. These results can be useful for providers considering procuring RZV and for state immunization programs considering ways to improve vaccination coverage.

Demographic, clinical, and epidemiologic characteristics of persons under investigation for Coronavirus Disease 2019-United States, January 17-February 29, 2020.

BACKGROUND: The Coronavirus Disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), evolved rapidly in the United States. This report describes the demographic, clinical, and epidemiologic characteristics of 544 U.S. persons under investigation (PUI) for COVID-19 with complete SARS-CoV-2 testing in the beginning stages of the pandemic from January 17 through February 29, 2020. METHODS: In this surveillance cohort, the U.S. Centers for Disease Control and Prevention (CDC) provided consultation to public health and healthcare professionals to identify PUI for SARS-CoV-2 testing by quantitative real-time reverse-transcription PCR. Demographic, clinical, and epidemiologic characteristics of PUI were reported by public health and healthcare professionals during consultation with on-call CDC clinicians and subsequent submission of a CDC PUI Report Form. Characteristics of laboratory-negative and laboratory-positive persons were summarized as proportions for the period of January 17-February 29, and characteristics of all PUI were compared before and after February 12 using prevalence ratios. RESULTS: A total of 36 PUI tested positive for SARS-CoV-2 and were classified as confirmed cases. Confirmed cases and PUI testing negative for SARS-CoV-2 had similar demographic, clinical, and epidemiologic characteristics. Consistent with changes in PUI evaluation criteria, 88% (13/15) of confirmed cases detected before February 12, 2020, reported travel from China. After February 12, 57% (12/21) of confirmed cases reported no known travel- or contact-related exposures. CONCLUSIONS: These findings can inform preparedness for future pandemics, including capacity for rapid expansion of novel diagnostic tests to accommodate broad surveillance strategies to assess community transmission, including potential contributions from asymptomatic and presymptomatic infections.

A diagnostic algorithm for detection of antibodies to influenza A viruses in dogs in Italy (2006-2008).

Since 2004, there have been several reports of Influenza A virus (FLUAV) infection in dogs. Dogs have been infected with equine influenza H3N8, avian influenza H3N2 and H5N1, and the pandemic H1N1 virus. Because of recent avian and equine influenza outbreaks in Italy, the objectives of the present study were to estimate the level of exposure of Italian dogs to influenza A viruses and to assess a diagnostic algorithm for detection of FLUAV exposure in dogs. Sera collected from 6,858 dogs from 2006 to 2008 were screened in a competitive enzyme-linked immunosorbent assay (cELISA) for antibodies to the highly conserved influenza A nucleoprotein. Samples positive in the cELISA were confirmed by testing in hemagglutination inhibition (HI) and fluorescent antibody test (FAT). Two seropositive dogs had antibodies to H3 hemagglutinin proteins, consistent with exposure to recent canine and equine subtype H3N8 viruses. Using a Bayesian model, the sensitivity and specificity of the cELISA were estimated as 93.98% (probability intervals [PI]: 81.67-99.08%) and 98.71% (PI: 98.43-98.96%), respectively. After accounting for the imperfect sensitivity and specificity of the cELISA, the Bayesian posterior prevalence of FLUAV exposure among tested Italian dogs was 0.5% (PI: 0.1-1.4%). The study results indicate that screening with a cELISA for influenza A nucleoprotein antibody, followed by confirmatory testing with HI and/or FAT, is a highly sensitive and highly specific approach for diagnosing FLUAV exposure in dogs.

Multistate outbreak of human Salmonella Typhimurium infections linked to live poultry from agricultural feed stores and mail-order hatcheries, United States 2013.

Live poultry-associated salmonellosis is an emerging public health issue in the United States. Public and animal health officials collaborated to investigate one of the largest (356 cases, 39 states) of these outbreaks reported to date. A case was defined as illness in a person infected with the outbreak strain of Salmonella Typhimurium with illness onset between 1 March and 22 October 2013. The median patient age was seven years (range: < 1-87 years); 58% of ill persons were children ≤ 10 years, 51% were female, 25% were hospitalized; 189 (76%) of 250 patients reported live poultry exposure in the week before illness; and 149 (95%) of 157 reported purchasing live poultry from agricultural feed stores. Traceback investigations identified 18 live poultry sources, including 16 mail-order hatcheries. Environmental sampling was conducted at two mail-order hatcheries. One (2.5%) of 40 duplicate samples collected at one hatchery yielded the outbreak strain. Live poultry are an important source of human salmonellosis, particularly among children, highlighting the need for educational campaigns and comprehensive interventions at the mail-order hatchery and agricultural feed store levels. Prevention and control efforts depend on a One Health approach, involving cooperation between public and animal health officials, industry, health professionals, and consumers.