Engineering Controls for Bioaerosols in Non-Industrial/Non-Healthcare Settings

The list of disease pathogens that can be transmitted in the air is extensive. This list includes the common cold, SARS, measles, Hansen’s disease (leprosy), polio, influenza, Legionella (Legionnaires’ disease and Pontiac fever), and tuberculosis (TB). TB, SARS-CoV-1, avian influenza, varicella, and now SARS-CoV-2 all have received public notice due not only to their known or assumed ability to be transmitted in the air rapidly from one individual to another, but also for their virulence. Other bioaerosols that can be transmitted through the air include bacteria, fungal spores and fragments, dust mites, and pollen. This document was developed to address control of bioaerosols transmission, primarily through ventilation and other engineering controls. This monograph will focus on engineering controls in non-industrial/ non-healthcare facilities such as office buildings, schools, public assembly, theaters, and governmental buildings. It does not, however, address ventilation in residences, either single or multi-family

Role of the B Allele of Influenza A Virus Segment 8 in Setting Mammalian Host Range and Pathogenicity.

UNLABELLED: Two alleles of segment 8 (NS) circulate in nonchiropteran influenza A viruses. The A allele is found in avian and mammalian viruses, but the B allele is viewed as being almost exclusively found in avian viruses. This might reflect the fact that one or both of its encoded proteins (NS1 and NEP) are maladapted for replication in mammalian hosts. To test this, a number of clade A and B avian virus-derived NS segments were introduced into human H1N1 and H3N2 viruses. In no case was the peak virus titer substantially reduced following infection of various mammalian cell types. Exemplar reassortant viruses also replicated to similar titers in mice, although mice infected with viruses with the avian virus-derived segment 8s had reduced weight loss compared to that achieved in mice infected with the A/Puerto Rico/8/1934 (H1N1) parent. In vitro, the viruses coped similarly with type I interferons. Temporal proteomics analysis of cellular responses to infection showed that the avian virus-derived NS segments provoked lower levels of expression of interferon-stimulated genes in cells than wild type-derived NS segments. Thus, neither the A nor the B allele of avian virus-derived NS segments necessarily attenuates virus replication in a mammalian host, although the alleles can attenuate disease. Phylogenetic analyses identified 32 independent incursions of an avian virus-derived A allele into mammals, whereas 6 introductions of a B allele were identified. However, A-allele isolates from birds outnumbered B-allele isolates, and the relative rates of Aves-to-Mammalia transmission were not significantly different. We conclude that while the introduction of an avian virus segment 8 into mammals is a relatively rare event, the dogma of the B allele being especially restricted is misleading, with implications in the assessment of the pandemic potential of avian influenza viruses. IMPORTANCE: Influenza A virus (IAV) can adapt to poultry and mammalian species, inflicting a great socioeconomic burden on farming and health care sectors. Host adaptation likely involves multiple viral factors. Here, we investigated the role of IAV segment 8. Segment 8 has evolved into two distinct clades: the A and B alleles. The B-allele genes have previously been suggested to be restricted to avian virus species. We introduced a selection of avian virus A- and B-allele segment 8s into human H1N1 and H3N2 virus backgrounds and found that these reassortant viruses were fully competent in mammalian host systems. We also analyzed the currently available public data on the segment 8 gene distribution and found surprisingly little evidence for specific avian host restriction of the B-clade segment. We conclude that B-allele segment 8 genes are, in fact, capable of supporting infection in mammals and that they should be considered during the assessment of the pandemic risk of zoonotic influenza A viruses.Wellcome Trust (Grant ID: 108070/Z/15/Z), Medical Research Council (Grant ID: MR/K000276/1), Biotechnology and Biological Sciences Research Council (Grant IDs: BB/J004324/1, BB/J01446X/1), Division of Intramural Research National Institute of Allergy and Infectious Diseases, University Of Edinburgh (Chancellor’s Fellowship)This is the final version of the article. It first appeared from the American Society for Microbiology via http://dx.doi.org/10.1128/JVI.01205-1

Engineering Controls for Bioaerosols in Non-Industrial/Non-Healthcare Settings

The list of disease pathogens that can be transmitted in the air is extensive. This list includes the common cold, SARS, measles, Hansen’s disease (leprosy), polio, influenza, Legionella (Legionnaires’ disease and Pontiac fever), and tuberculosis (TB). TB, SARS-CoV-1, avian influenza, varicella, and now SARS-CoV-2 all have received public notice due not only to their known or assumed ability to be transmitted in the air rapidly from one individual to another, but also for their virulence. Other bioaerosols that can be transmitted through the air include bacteria, fungal spores and fragments, dust mites, and pollen. This document was developed to address control of bioaerosols transmission, primarily through ventilation and other engineering controls. This monograph will focus on engineering controls in non-industrial/ non-healthcare facilities such as office buildings, schools, public assembly, theaters, and governmental buildings. It does not, however, address ventilation in residences, either single or multi-family

Should food or supplements be used in the community for the treatment of disease-related malnutrition?

Strategies are needed for community-based treatment of disease-related malnutrition (DRM), which is a common debilitating condition that in the UK is estimated to cost >£7×10? annually. Whilst dietary fortification and counselling are often used as a first-line treatment for malnutrition, the numbers of dietitians available to undertake and oversee such practices are currently insufficient to address the extent of DRM in primary care. Although dietary fortification and counselling can improve nutritional (primarily energy) intake, the evidence base for this practice is weak and it needs addressing with well-designed trials that assess clinically-relevant outcome measures and costs. Liquid oral nutritional supplements (ONS) are increasingly used in the community, often in combination with dietary counselling. The larger evidence base of trials that have assessed ONS suggests that nutritional intake and some functional outcomes can be improved in some patient groups in the community. Although meta-analysis indicates significant reductions in mortality (odds ratio 0·59 (95% CI 0·48, 0·72), n 3258) and complication rates (odds ratio 0·41 (95% CI 0·31, 0·53), n 1710) with ONS v. routine care, few of these studies are community based. Thus, the impact of ONS on clinical outcome, healthcare use and costs requires further assessment. Similarly, the clinical and cost efficacy of other strategies (e.g. sensory enhancement, music, behavioural therapy), alone or in combination with other treatments, requires greater investigation in order to meet the challenge of treating DRM more effectively and cheaply in the future