Benefits of flu vaccination for persons with diabetes mellitus: A review

Diabetes mellitus imposes a significant and increasing burden on society, with major consequences for human health, welfare and the economy worldwide. Persons with diabetes mellitus are at increased risk of developing severe complications after influenza virus infection and guidelines advise vaccination. The present evidence for influenza vaccine effectiveness in persons with diabetes mellitus is mainly based on observational studies with clinical endpoints like hospitalization and death, indicating a beneficial reduction of morbidity and mortality. Further supportive evidence comes from serological studies, in which persons with diabetes mellitus usually develop similar antibody levels after vaccination as healthy people. Observational studies may be prone to selection bias, and serological studies may not completely mirror vaccine effectiveness in the field. Although more controlled trials in persons with diabetes mellitus with laboratory-confirmed, influenza-specific outcomes would be desirable to better estimate the effect of vaccination, the currently available data justify routine influenza vaccination in persons with diabetes mellitus. As in this risk group, the use of influenza vaccine is far below target worldwide, efforts should be made to increase vaccination coverage.     

Impact of live attenuated influenza vaccination programme for healthy children in Northern Ireland: A comparison of seven influenza seasons, 2010/11–2016/17

Seasonal influenza vaccination for healthy children was introduced in Northern Ireland in the 2013/14 flu season, with an initial pilot year involving two specific cohorts, followed by rollout to all children aged 4–11 years in subsequent seasons. This study aimed to examine the impact of that programme on the burden of flu in primary care over the study period 2010/11–2016/17.Two routine indicators were used to measure impact – GP in-hour consultations and out-of-hour calls for influenza and influenza-like-illness (ILI). Analysis was conducted overall and stratified by age; rates in children under 14 years of age to measure direct impact and rates in individuals 14 years and over to measure indirect impact. Seven influenza seasons were included, three pre-programme seasons (2010/11–2012/13: phase 0), one pilot season (2013/14: phase 1), and three post-programme seasons (2014/15–2016/17: phase 2).High uptake of vaccination was observed from the programme introduction, with consistent uptake of over 50% in pre-school age groups and over 75% in primary school age groups. Statistically significant reductions were found in GP in-hours consultations and in out-of-hour calls in phase 2 compared to phase 0, both overall (GP in-hours RR 0.61, 95% CI 0.38–0.98, p = .040; out-of-hours RR 0.51, 95% CI 0.27–0.97, p = .041) and in the under 14 years group (GP in-hours RR 0.38, 95% CI 0.19–0.75, p = .006; out-of-hours RR 0.39, 95% CI 0.19–0.83, p = .014).Our results suggest that there have been reductions in the burden of flu in primary care settings overall and in children aged under 14 years in the seasons since the introduction of healthy children influenza vaccination. Further seasons should be added to subsequent analyses to strengthen this evidence.     

Concurrent and cross-season protection of inactivated influenza vaccine against A(H1N1)pdm09 illness among young children: 2012–2013 case–control evaluation of influenza vaccine effectiveness

In 2012–2013, we examined 1729 laboratory-confirmed A(H1N1)pdm09 influenza cases matched 1:1 with healthy controls and estimated influenza vaccine effectiveness (VE) for trivalent inactivated influenza vaccine (IIV3) to be 67% (95% confidence interval = 58–74%) for ages 8 months to 6 years old. Among children aged 8–35 months old, VE for fully vaccinated children (73%, 60–81%) was significantly higher than VE for partially vaccinated children (55%, 33–70%). Significant cross-season protection from prior IIV3 was noted, including VE of 31% (8–48%) from IIV3 received in 2010–2011 against influenza illness in 2012––2013 without subsequent boosting doses.     

ISC1, a new Leishmania donovani population emerging in the Indian sub-continent: Vector competence of Phlebotomus argentipes

Visceral leishmaniasis (VL), the most severe form of the disease, is caused by Leishmania donovani in the Indian sub-continent (ISC). Whole genome sequencing studies revealed that two parasite populations exist in the ISC: a main population named the Core Group (CG) found mostly in the lowlands, and a new, genetically different subpopulation called ISC1. Parasites belonging to the CG were shown to be responsible for the recent epidemics, while the ISC1 variant was originally identified in hilly districts of Nepal and was later on increasingly found in the lowlands. Importantly, the ISC1 and CG isolates differ in their drug susceptibility and virulence signatures, suggesting that ISC1 constitutes an emerging and functionally different variant of L. donovani. In present study we aimed to address the potential of ISC1 transmission by the natural vector of L. donovani in the lowlands, Phlebotomus argentipes. By experimental infection of sand flies with parasites of the different genotypes, we demonstrate that ISC1 and CG strains are developing similarly in P. argentipes, suggesting that P. argentipes is a fully competent vector for ISC1 parasites. Integration of previous and current findings shows thus that ISC1 is a new and different variant of L. donovani, fully adapted to spread in the ISC through the main vector. This information is directly useful for managers of the elimination program. Furthermore, integration of our successive studies (genotyping, phenotyping and vector competence) demonstrates the relevance of molecular surveillance and should be of interest for scientists working on vector borne diseases and control managers.     

Efficacy of a high potency O1 Manisa foot-and-mouth disease vaccine in cattle against heterologous challenge with a field virus from the O/ME-SA/Ind-2001 lineage collected in North Africa

Outbreaks of foot-and-mouth disease (FMD) in North Africa (2013) and the Gulf States (2013) of the Middle East have been caused by a FMD viral lineage (O/ME-SA/Ind-2001) that was before 2013 restricted to the Indian Sub-continent. This study was undertaken to assess the in vivo efficacy of a FMD virus emergency vaccine type O₁ Manisa against heterologous challenge with a representative field virus (O/ALG/3/2014) from this emerging lineage. This widely available vaccine was selected since in vitro vaccine-matching results gave inconclusive results as to whether or not it would be protective. Three groups of five cattle were vaccinated with O₁ Manisa (homologous potency ≥6PD₅₀/dose) using study guidelines outlined in the European Pharmacopeia, and challenged at 21 days post-vaccination by tongue inoculation. All animals that were vaccinated with the lowest dose (1/16) of vaccine developed generalised FMD, defined as vesicular lesions at the feet. One animal vaccinated with a 1/4 dose of the vaccine also developed generalised disease, as did two animals vaccinated with the full dose of vaccine. These results indicate that the heterologous potency of this high potency O₁ Manisa vaccine was approximately 3.5 PD₅₀/dose. These data support the use of the O₁ Manisa vaccine for FMD control in areas where FMDV is endemic e.g. North Africa, and motivate further studies to evaluate other vaccine candidates (or multivalent combinations) that might be potentially used for emergency purposes in FMD-free settings.