Environmental sampling for SARS-CoV-2 in long term care facilities: lessons from a pilot study [version 2; peer review: 2 approved]

Background: The SARS-CoV-2 pandemic has highlighted the risk of infection in long-term care facilities (LTCF) and the vulnerability of residents to severe outcomes. Environmental surveillance may help detect pathogens early and inform Infection Prevention and Control (IPC) measures in these settings. Methods: Upon notification of SARS-CoV-2 outbreaks, LTCF within a local authority in South West England were approached to take part in this pilot study. Investigators visited to swab common touch-points and elevated ‘non-touch’ surfaces (>1.5m above ground level) and samples were analysed for presence of SARS-CoV-2 genetic material (RNA). Data were collected regarding LTCF infrastructure, staff behaviours, clinical and epidemiological risk factors for infection (staff and residents), and IPC measures. Criteria for success were: recruitment of three LTCF; detection of SARS-COV-2 RNA; variation in proportion of SARS-CoV-2 positive surfaces by sampling zone; and collection of clinical and epidemiological data for context. Results: Three LTCFs were recruited, ranging in size and resident demographics. Outbreaks lasted 63, 50 and 30 days with resident attack rates of 53%, 40% and 8%, respectively. The proportion of sample sites on which SARS-CoV-2 was detected was highest in rooms occupied by infected residents and varied elsewhere in the LTCF, with low levels in a facility implementing enhanced IPC measures. The heterogeneity of settings and difficulty obtaining data made it unfeasible to assess association between environmental contamination and infection. A greater proportion of elevated surfaces tested positive for SARS-CoV-2 RNA than common touch-points. Conclusions: SARS-CoV-2 RNA can be detected in a variety of LTCF outbreak settings, both on common-touch items and in elevated sites out of reach. This suggests that further work is justified, to assess feasibility and utility of environmental sampling for infection surveillance in LTCF

Techniques for the quantification of biofouling

For this chapter, we have collated from the authors in this book approaches and techniques for the quantification and qualification of biofouling and have presented most of it in referenced tabular form to permit easy access to the information (Table 22.1). There are also two more thorough sections neither of which has been published before: one on the sampling of hulls of large vessels and another which details a broadly applicable advanced stereo logical techniquefor the quantification of fouling. The collection is unlikely to be fully comprehensive, but we have aimed to give the reader techniques for quantification of different levels of the biofouling community, from biofilm to macroorganisms, and from single species to the whole community. The techniques are for use in the office, laboratory or the field and range from cheap to costly. All of these techniques have proven their usefulness and with this chapter we would liketo improve the exchange of approaches to biofouling quantification between the different disciplines. For this reason, the techniques come from across the basic and applied sciences in industry, biology and medicine