The COVID-19 Booster: Australia experiences surge in cases as new wave begins

Australia’s new COVID-19 wave has arrived.

Over 40,000 new cases were reported in the past week, representing a nationwide new case jump of roughly 20%.

It comes amid an increase of new sublineages of the SARS-CoV-2 detected in cases and wastewater sampling around the country.

Those include Omicron variants like BQ and XBB, which could account for at least 15% of cases based on sampled sequences. Overall, these and other new versions of the virus are on the rise in Australia, while the progenitor BA.4 and BA.5 strains are declining.

“We’re starting to see an increase in COVID cases, and changes in the variants circulating in New South Wales, which tells us that we’re entering the next COVID wave,” NSW chief health officer Dr Kerry Chant said in a pre-recorded message released by the state’s health department this week.

“By looking at all the local information we have and what’s happening overseas, we believe COVID cases will rise in the coming weeks.”

Hybrid immunity – a combination of antibodies from vaccination and prior infection – should leave most healthy adults in a strong position to fight off a subsequent infection, although more vulnerable groups such as those with underlying health conditions, elderly and immunocompromised people may be at greater risk of severe illness, according to health authorities.

Masks, social distancing, hand hygiene and isolation with symptoms, remains important to avoid the virus spreading.

Read more: Where do these new Omicron variants come from?

COVID-19 by the numbers

Covid dashboard
^Aggregated data from Australian states and territories. * Data from Australian Department of Health

COVID-19 News in brief

A blueprint to bring the pandemic to a close

Nearly 400 researchers from 112 countries have released a series of statements and recommendations relating to communication, health systems, vaccination, preventative measures, treatment and care that will ‘close’ the COVID-19 pandemic. Among areas of broadest consensus, these experts recommend a whole-of-society strategy that incorporates multiple stakeholders, whole-of-government approaches that enhance health system responsiveness and a ‘vaccines-plus’ strategy that combines an effective vaccination regime with other preventative measures and social incentives. The report has been published in Nature.

Man with COVID-19 for 411 days finally cleared of virus

A weakened immune system prevented a 59-year-old man from overcoming his infection with SARS-CoV-2 for more than a year. The British man is the subject of research published in Clinical Infectious Disease by a team from Guy’s and St Thomas’ Trust and King’s College London.   After originally testing positive for the virus in December 2020, at the beginning of the pandemic, and later recovering, the man continued testing positive to the virus until January this year. His case was treated with neutralising antibodies best suited to his particular, albeit repeated infection.

Back to Bat

Researchers from Rochester Institute of Technology (USA) publishing in Royal Society Open Science have found that SARS-CoV-2 is a spill over risk back to bat populations from which the original strain likely originated. Simulations reversed transmission scenarios to test whether currently circulating strains that have mutated from the ancestral virus have the potential to cross over to bats. They found that although some mutations may limit certain sub lineages and variants to humans, SARS-CoV-2 is broadly capable of jumping species lines three years after the pandemic started.

COVID-19 causes Parkinson’s-style brain inflammation

Biomedical scientists and virologists at the University of Queensland have found COVID-19 triggers the same inflammatory reactions in the brain as Parkinson’s and Alzheimer’s diseases – flagging a new risk associated with the disease.

Researchers infected the microglia immune cells present in brain tissue with SARS-CoV-2.

The cells’ reaction was identical to that in real brains – a ‘fire’ that progressively destroys neurones over a long period of time.

COVID-19 also appears to intensify this degenerative process where proteins linked to Parkinson’s are already present in the brain.

“It’s kind of a silent killer, because you don’t see any outward symptoms for many years,” says Dr Albornoz Balmaceda, one of the co-leads of the study, published in Molecular Psychiatry.

“It may explain why some people who’ve had COVID-19 are more vulnerable to developing neurological symptoms similar to Parkinson’s disease.”

Five times the COVID-19 severity risk causes by one gene variant

A sex-linked gene could increase the risk of severe COVID-19 five-fold, according to researchers from McGill University in Canada. The gene is present on the human X chromosome – twice present in women and only once in men. An analysis of more than five thousand severe cases of COVID-19 across 12 countries, found the TLR7 receptor on the X chromosome was linked to 5.3 times greater likelihood of a person having a serious infection, irrespective of gender.

Longer reads and audio

COVID-19 variants have landed

New COVID-19 sub lineages like BQ and XBB have been detected in Australian cases for several months, but are now increasing in number as a new wave beckons.

Story by Matthew Agius

The Science Briefing: What do we know about the new subvariants

Dr Sophie Calabretto and Matthew Agius discuss what the new series of SARS-CoV-2 strains means.

Listen to the episode

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