And Melbourne researchers are recruiting for a trial of two homegrown vaccine candidates.
Welcome to The Medical Republic’s Covid Catch-Up.
It’s the latest covid-19 news in one convenient post. Email bianca@biancanogrady.com with tips, comments or suggestions.
28 March
- Co-infection with covid and influenza associated with two-fold increase in mortality.
- Doherty Institute recruiting for clinical trial of two new covid vaccines.
- Monoclonal antibody combination of tixagevimab plus cilgavimab can be used in at-risk unvaccinated adults.
- Early aspirin in moderate covid could reduce risk of death or pulmonary embolism.
- Australia’s biosecurity emergency border measures to end on 17 April.
- Global tuberculosis infections drop during covid, but decline in TB deaths slows due to healthcare disruptions.
Coinfection with covid and influenza is associated with a four-times greater risk of needing mechanical ventilation, and more than two-times greater risk of death, research suggests.
A research letter published in The Lancet presents the results of an observational study of nearly 7000 adults with SARS-CoV-2 infection admitted to hospital in the UK between February 2020, and December 2021 and who were tested for other respiratory viruses.
Of these, 583 patients had respiratory coinfections, and researchers found that those coinfected with influenza were just over four times more likely to be ventilated, and 2.3 times more likely to die than those admitted just with covid after adjusting for factors including age, sex, and comorbidities.
They didn’t see a significant effect of coinfection with adenoviruses or respiratory syncytial viruses.
The authors said the findings emphasised the importance not only of vaccinating against both covid and influenza, but also of in-hospital testing of covid patients for coinfection with influenza to identify patients who might be at greater risk of severe disease.
Australian researchers have brought two covid vaccine candidates to clinical trial readiness and are recruiting trial volunteers.
Scientists at the Peter Doherty Institute in Melbourne – most famous for its covid modelling – have developed two new covid vaccines that both focus on the receptor binding domain of the SARS-CoV-2 spike protein, which is the part of the spike protein that binds to the ACE2 receptor on human cells.
The section of that protein was taken from the Beta variant – originally reported in South Africa – which shares two key mutations with the Omicron variant. Researchers hope this means the vaccine will offer greater protection against Omicron than existing vaccines.
One vaccine contains part of the virus protein itself, while the other is an mRNA vaccine containing the genetic sequence for the receptor binding domain.
The Doherty Institute is looking for around 100 volunteers who have had their third dose of existing covid vaccines at least three months ago, for a randomised, placebo-controlled phase 1 study. People who have had covid are also eligible as long as their infection was more than three months ago.
The monoclonal antibody combination of tixagevimab plus cilgavimab can be considered for use in unvaccinated adults with covid, who are not on oxygen but who have risk factors for severe disease, say the expert group behind Australia’s living guidelines on covid.
The National Covid-19 Clinical Evidence Taskforce has updated its advice on the antibody combination – known as Evusheld – following clinical trial evidence suggesting that the treatment “probably” decreases the risk of hospitalisation if given within five days of symptom onset.
They also suggested it could be used in vaccinated immunocompromised adults, or in those not up to date with vaccinations but at high risk of severe disease.
Early aspirin in people admitted to hospital with moderate covid appears to reduce the risk of pulmonary embolism and death.
A paper published in JAMA Network Open describes the findings of an observational cohort study of more than 112,000 adults hospitalised patients with moderate covid, around 13% of whom received aspirin on their day of admission.
Researchers saw that in-hospital mortality at 28 days was 15% lower in those treated with aspirin compared to those who weren’t, and the rate of pulmonary embolism was 29% lower in the aspirin group. The effects were even more evident among patients aged over 60 years, and those with one or more comorbidities.
Australia’s biosecurity emergency border restrictions are finally coming to an end on 17 April, having been in place since March 2020.
International travellers will no longer need a negative pre-departure RAT before leaving for Australia, but they will have to provide proof of double-vaccination with one of the vaccines recognised by Australian health authorities. Travellers will also still have to wear masks on board.
New tuberculosis diagnoses in the US and Europe have dropped significantly during the pandemic.
The US CDC has released data showing a 20% drop in new TB infections in 2020, and a persistent 13% decline compared to pre-pandemic levels since then, while the European Centre for Disease Control and Prevention recorded a 24% drop from 2019 to 2020.
It’s not yet clear how much of the reduction is a genuine decline in cases – which could be the result of mask-wearing, social distancing and other covid public health measures – and how much is due to late or missed diagnoses caused by pandemic interruptions to healthcare.
The long-running decline in the death rate from tuberculosis also plateaued during the pandemic. Dr Hans Henri P. Kluge, WHO Regional Director for Europe, says this may be the result of healthcare disruptions that have affected both diagnosis and treatment.
Tuberculosis remains the world’s second deadliest infectious disease after covid, and numerous health organisations used World Tuberculosis Day on 24 March to remind the world of the need for ongoing investment in prevention, diagnosis and treatment.
