One Flu Over the Cuckoo's Nest: Is Concern for Avian Flu Warranted in a Busy Clinic?

At present H5N1 is mainly a disease of birds. However, with ongoing mutation, the virus may develop the ability to bind to human upper airway receptors and be easily passed between human beings by coughing and sneezing. Care providers must be prepared to recognize isolated cases, clusters of cases, or possibly sudden, overwhelming numbers of cases. Most importantly, guidelines for recognition and testing suspected cases should be available for reference in each clinic. This article provides background in the biology, epidemiology, and natural history of H5N1 infection, along with guidelines for prevention, diagnosis, and advice for treatment.     

Rapid detection of new B/Victoria-lineage haemagglutinin variants of influenza B viruses by pyrosequencing

During 2016/2017, several antigenically and genetically distinct variant viruses of the influenza B/Victoria/2/87-lineage (B/Vic) viruses, which have either deletions or mutations in the haemagglutinin (HA) emerged and co-circulated with other influenza B viruses from both the B/Vic and B/Yamagata/16/88-lineages (B/Yam). In this study we developed a pyrosequencing assay that can detect and differentiate multiple influenza B virus variants currently in circulation. The assay targets a region of HA sequence that is unique for each of the B/Yam, B/Vic and B/Vic variant viruses. Our results demonstrated that it is a rapid, robust, high-throughput assay, highly sensitive and specific in differentiating among the B/Yam, B/Vic and B/Vic variant viruses, giving it an advantage over an existing rRT-PCR method. It works well for influenza virus isolates as well as original clinical respiratory specimens, and can therefore be used to provide important information for surveillance by closely monitoring the spread of these B/Vic variants.     

Influenza vaccine effectiveness against influenza-associated hospitalization in 2015/16 season,Beijing, China

BackgroundVaccination is recommended to prevent influenza virus infection and associated complications. This study aimed to estimate the influenza vaccine effectiveness (VE) against hospitalization in the 2015/16 season in Beijing.MethodsPatients who were hospitalized in the 5 study hospitals between 1 Oct 2015 and 15 May 2016 were recruited. Influenza vaccination status was obtained for PCR-confirmed influenza patients and the selected controls who tested negative for the virus. Conditional logistic regression was used to estimate the influenza VE matching by calendar week, and adjusting for age, study sites, underlying medical conditions, smoking status, and hospital admissions over the past 12 months.ResultsThe overall VE was −37.9% (95% CI: −103.3, 6.5) against laboratory-confirmed influenza-associated hospitalization. The 2015–16 seasonal vaccine was had −61.9% (95% CI: −211.9, 15.9), −5.4% (95% CI: −108.1, 46.6) and −45.2% (95% CI: −152.6, 16.5) effectiveness to prevent infection from A(H1N1)pdm09, A(H3N2) and influenza B, respectively.ConclusionsInfluenza vaccination did not show effective protection against hospitalization with influenza in 2015/16 season in Beijing.     

Influenza vaccination responses: Evaluating impact of repeat vaccination among health care workers

ObjectiveTo compare the antibody response to influenza between health care workers (HCWs) who have received multiple vaccinations (high vaccination group) and those who have received fewer vaccinations (low vaccination group).DesignProspective serosurvey.SettingTertiary referral hospital.ParticipantsHealthcare workers.MethodsHealthcare workers were vaccinated with the 2015 southern hemisphere trivalent influenza vaccine. Influenza antibody titres were measured pre-vaccination, 21–28 days post-vaccination and 6 months post-vaccination. Antibody titres were measured using the haemagglutination inhibition assay. Levels of seropositivity and estimated geometric mean titres were calculated.ResultsOf the 202 HCWs enrolled, 182 completed the study (143 high vaccination and 39 low vaccination). Both vaccination groups demonstrated increases in post-vaccination geometric mean titres, with greater gains in the low vaccination group. Seropositivity remained high in both high and low vaccination groups post-vaccination. The highest fold rise was observed among HCWs in the low vaccination group against the H3N2 component of the vaccine.ConclusionsBoth high and low vaccination groups in our study demonstrated protective antibody titres post-vaccination. The findings from the current study are suggestive of decreased serological response among highly vaccinated HCWs. More studies with larger sample sizes and a greater number of people in the vaccine-naïve and once-vaccinated groups are required to confirm or refute these findings before making any policy changes.     

Regulatory considerations in the clinical development of vaccines indicated for use during pregnancy

Despite supportive public health policies (e.g., ACIP recommendations), the potential for providing clinical benefit through maternal immunization has yet to be fully realized. For vaccines already licensed and approved for use in adults, specific FDA approval for use during pregnancy to prevent disease in the mother and/or infant may have a significant impact on uptake and usage in pregnant women. In addition, for either a licensed vaccine or a novel vaccine, FDA approval for use during pregnancy would result in labeling that would serve as a resource for practitioners and would facilitate the safe and effective use of the vaccine during pregnancy.In the U.S., while many vaccines are approved for use in adults and most are not contraindicated for use in pregnant women, no vaccine is licensed for use specifically during pregnancy. Among the perceived obstacles hindering the clinical development of vaccines for use in pregnancy, regulatory issues are frequently cited. One aim of this article is to address the perceived regulatory obstacles. General concepts and regulatory considerations for clinical safety and effectiveness evaluations for vaccines indicated for use during pregnancy will be discussed. This discussion is not intended to establish data requirements or to articulate agency policy or guidance regarding specific vaccine products.     

Paediatric pulmonary echinococcosis: A neglected disease

Echinococcosis is a worldwide public health problem causing considerable paediatric morbidity and mortality in endemic areas. The presentation of cystic echinococcosis (CE) varies by age. Unlike adults, where hepatic involvement is common, pulmonary CE is the dominant site in the paediatric population.Pulmonary cysts are typically first seen on chest X-ray, either as an incidental finding or following respiratory symptoms after cyst rupture or secondary infection of the cyst. In children, pulmonary cysts have a broad differential diagnosis, and a definitive diagnosis relies on the combination of imaging, serology, and histology. In countries with high infectious burdens from diseases such as acquired immunodeficiency syndrome (AIDS) and tuberculosis (TB), the diagnosis is additionally challenging, as atypical infections are more common than in developed countries. Pulmonary CE is treated with a combination of surgery and chemotherapy.     

Immunogenicity of an investigational hepatitis B vaccine with a toll-like receptor 9 agonist adjuvant (HBsAg-1018) compared with a licensed hepatitis B vaccine in subpopulations of healthy adults 18–70 years of age

BackgroundImmunologic response to a complete vaccine regimen of currently licensed alum-adjuvanted hepatitis B vaccines is reduced in several subpopulations, including older adults, men, obese persons, and smokers. Two phase 3 trials in healthy adults demonstrated that 2 doses over 1 month of an investigational hepatitis B vaccine (HBsAg-1018) induced superior seroprotection rates (SPRs) to 3 doses over 6 months of the licensed vaccine Engerix-B^® (HBsAg-Eng).MethodsAn exploratory analysis of immunogenicity was conducted in subpopulations from pooled data for the 2 phase 3 trials.ResultsIn each subpopulation, the peak SPR in the HBsAg-1018 group was statistically significantly higher than the peak SPR in the HBsAg-Eng group. Peak HBsAg-1018 SPRs ranged from 91.6% to 99.7%, while peak HBsAg-Eng SPRs ranged from 67.7% to 92.9%.ConclusionIn these exploratory analyses, 2 doses of HBsAg-1018 induced statistically significantly higher rates of seroprotection than 3 doses of HBsAg-Eng across all subpopulations.