How genomic sequencing gives authorities a ‘high resolution’ understanding of COVID-19 outbreaks

How genomic sequencing gives authorities a ‘high resolution’ understanding of COVID-19 outbreaks

  • While Victoria’s genomic sequencing of the outbreaks in Melbourne are kept under wraps, experts and politicians say such information is not as important for NSW.
  • Genome sequencing, which maps minute changes in the virus to identify particular strains and where they came from, is the tool that linked the Crossroads Hotel outbreak to the strain of COVID-19 sweeping Melbourne.

On Tuesday, Victoria’s Chief Health Officer Brett Sutton said the sequencing of Melbourne’s outbreaks would not be revealed as it was being examined by a judicial inquiry.

But speaking on Triple M on Wednesday, Prime Minister Scott Morrison said the important thing for NSW was discovering the strain in the Crossroads Hotel outbreak had come from Victoria.

“That just means that in terms of community outbreak in NSW, that hasn’t come from within NSW,” he said. “It just means that we understand the nature of the problem there and that’s helping them get on top of that very quickly.”

Virologist Dr Megan Steain reiterated the PM’s sentiment.

“The fact they can trace it from one particular source, gives us more confidence that what is not happening is cryptic transmission throughout the community,” she said.

“The fact we know it’s got one source is reassuring and hopefully means we can contain the outbreak.”

Professor Vitali Sintchenko, director of the Centre for Infectious Diseases and Microbiology-Public Health at the University of Sydney and a microbiologist with NSW Health Pathology, said whole genome mapping provides the fingerprints of each virus sample, which can be compared with other samples to provide a deeper understanding of the spread of the disease.

“With genomics, you have this high-resolution capability to understand transmission pathways,” he said.

“Epidemiologists generate hypotheses about contacts by talking to people, microbiologists or scientists can generate this hypothesis without talking to people but by comparing genomes.”