Study suggests elderly care home outbreaks in England were caused by multiple indepedent infections and also within-home spread

September 23, 2020

New research presented at this week's ESCMID Congress on Coronavirus Disease (ECCVID, held online 23-25 September) shows that outbreaks of COVID-19 in elderly care homes were caused by multiple independent infections from outside, plus within care home spread. There is also evidence of transmission between residents and healthcare workers, including paramedics, possibily linking care home outbreaks to hospital outbreaks (though the direction of transmission between individuals could not be confirmed). The study is by Dr William Hamilton, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK, and colleagues.

COVID-19 poses a major challenge to infection control in care homes. SARS-CoV-2 is readily transmitted between people in close contact and causes disproportionately severe disease in older people. Understanding the burden and transmission dynamics of COVID-19 in care home residents is therefore a public health priority.

In this study, data and SARS-CoV-2 samples were collected from patients in the East of England between 26th February and 10th May 2020, and tested at the Cambridge Public Health England Clinical Microbiology Laboratory, UK. Care home residents were identified using address search terms and Care Quality Commission registration information. Samples were genetically sequenced at the University of Cambridge or the Wellcome Sanger Institute, and viral clusters were identified within each care home based on integrated genomic and temporal differences between cases.

A total of 7,406 SARS-CoV-2 positive samples from 6,600 patients were identified, of which 1,167 (18%) were residents from 337 different care homes. 40% of the care home residents tested acutely at Cambridge University Hospitals NHS Foundation Trust (CUH) died, roughly double the unadjusted mortality rate for non-care home residents.

Genetic sequences (genomes) were available for 700/1,167 (60%) residents from 292 care homes, and 409 distinct viral clusters were defined. The largest clusters comprised more than 10 samples from the same care home, consistent with care home COVID-19 outbreaks.

"Care homes with multiple clusters suggested multiple independent viral acquisitions among residents, " say the authors. "We also identified several probable transmissions between care home residents and healthcare workers, based both in the community (carers and paramedics) and the hospital, suggesting a potential link between care home-associated and healthcare-associated COVID-19 infections."

They conclude: "We present a large genomic epidemiology study of care home-associated COVID-19 infections in the UK. Care home residents had a significant burden of COVID-19 infections and high mortality. Larger viral clusters suggested within-care home outbreaks, while multiple clusters per care home suggested independent acquisitions. Integrated genomic and epidemiological data collected at scale can provide valuable insights into SARS-CoV-2 transmission dynamics; in future, such analyses could be used for targeting public health responses."

European Society of Clinical Microbiology and Infectious Diseases

Related Transmission Articles from Brightsurf:

In the Netherlands, two-way transmission of SARS-CoV-2 transmission on mink farms
In the Netherlands, whole genome sequencing of SARS-CoV-2 outbreaks on 16 mink farms has revealed virus transmission between human to mink, as well as from mink to human.

Study describes COVID-19 transmission pattern
Model developed by Brazilian researchers predicts spatial and temporal evolution of epidemic diseases and can help plan more effective social isolation programs with less socio-economic impact.

How to better understand what makes a virus win during transmission?
The framework, published in Frontiers in Microbiology, was applied on transmission data of the influenza virus, and offers to be a new tool for anticipating the consequences of microbial diversity and optimizing disease control measures.

Evaporation critical to coronavirus transmission as weather changes
As COVID-19 cases continue to rise, it is increasingly urgent to understand how climate impacts the spread of the coronavirus, particularly as winter virus infections are more common and the northern hemisphere will soon see cooler temperatures.

Decorating windows for optimal sound transmission
Glass windows typically offer some amount of sound proofing, sometimes unintentionally.

New malaria transmission patterns emerge in Africa
An international study reveals how future climate change could affect malaria transmission in Africa over the next century.

Reducing transmission risk of livestock disease
The risk of transmitting the livestock virus PPRV, which threatens 80% of the world's sheep and goats, increases with certain husbandry practices, including attendance at seasonal grazing camps and the introduction of livestock to the herd.

Mouthwashes could reduce the risk of coronavirus transmission
Sars-Cov-2 viruses can be inactivated using certain commercially available mouthwashes.

Study reveals COVID-19 transmission rate on trains
A study by scientists from the University of Southampton has examined the chances of catching COVID-19 in a train carriage carrying an infectious person.

Defining paths to possible mother to child coronavirus transmission
UC Davis Health researchers took a critical step in defining the possible paths for SARS-CoV-2 causing COVID-19 to get transmitted from the mother to her newborn baby.

Read More: Transmission News and Transmission Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to