COVID Booster: Hamsters, mental health, and self-swabs for kids

Lab-grown nose helps researchers understand early stages of SARS-CoV-2 infection

Researchers at Baylor College of Medicine in the US have successfully developed a human nose organoid that can be used to study interactions between viruses and the cells that line the inside of the nose.

Organoids are lab-grown proxies for entire organs, usually achieved by culturing cells and coaxing them into useful structures that replicate tissues or parts of organs found in the body. They’re a very useful way to study physiology in extreme detail.

In this case, human nasal epithelial cells were obtained from nasal swabs and grown into organoids on tissue culture plates.

The research team used their nose model to study infection of the nasal epithelium by SARS-CoV-2 as well as respiratory syncytial virus (RSV).

“In the case of respiratory viruses, such as SARS-CoV-2 and RSV, the infection begins in the nose when one breathes in the virus,” says corresponding author Dr Pedro Piedra.

“The human nose organoids we have developed provide access to the inside of the human nose, enabling us to study the early events of the infection in the lab.”

Mental health impacts of Australia’s COVID-19 border closures

A new Australian study has found that extended international border closures due to COVID-19 were linked to high levels of psychological distress for those affected.

The research considered responses from almost 4,000 people living both in and outside Australia.

“The vast majority of participants reported being negatively affected by the restrictions and showed high or very high levels of psychological distress,” says Flinders University researcher Kathina Ali, first author on the study.

The most common reason cited for negative impacts on mental health was the desire to be with family and friends (81.1% of respondents), followed by economic or employment reasons (4.9%) and study reasons (4.1%).

These hits to mental health have implications not just for those experiencing them but for the broader society as well.

“Health and mental health care providers should be aware of this crisis and provide appropriate support options and practical strategies to mitigate the risk of further deterioration,” says Ali.

“Qualitative data which is currently prepared for publication demonstrates the significant impact, with respondents reporting that they intend to leave or have left Australia due to the ongoing stress of not being able to see families,” adds co-author Dan Fassnacht.

Five-year-olds can swab themselves

If you’ve waited behind a five-year-old at a PCR testing station, you might think them naturally resistant to the nasal swab. But a study in JAMA Network Open has found that not only can children learn to tolerate the swab – they can be taught to collect their own samples.

But they need time to improve. The study tracked 296 children who were self-testing at a primary school in California, US, from September 2020 to June 2021. Over the year, self-swabbing got more accurate, and the children got faster.

“As expected when piloting an unfamiliar task, error rates began relatively high in September, around 10% of interactions, but rapidly decreased to 2.9% within 4 weeks,” write the authors in their paper.

A drug that protects hamsters from COVID-19

Hamsters have become an unlikely victim of the pandemic, as Hong Kong’s outbreak was traced to infected animals, leading to a cull.

But a group of Belgian researchers has a solution: the anti-viral drug PF-07321332 can protect Syrian hamsters from infection and lower the risk of transmission.

Published in Nature Communications, the research involved both cell studies of the drug against COVID, and studies in hamsters.

Hamsters that were infected with the Beta and Delta variants of COVID-19 and then treated with the drug for three days didn’t pass the virus on to other hamsters.

Long COVID could be linked to the vagus nerve

The vagus nerve, which stretches from the brainstem through to the abdomen, might be contributing to long COVID.

A group of researchers from University Hospital Germans Trias i Pujol, Spain, have reported that 228 out of 348 (66%) long COVID patients in their ongoing trial have symptoms related to vagus nerve dysfunction.

They reported these findings at the European Congress of Clinical Microbiology & Infectious Diseases.

“In this pilot evaluation, most long COVID subjects with vagus nerve dysfunction symptoms had a range of significant, clinically relevant, structural and/or functional alterations in their vagus nerve, including nerve thickening, trouble swallowing, and symptoms of impaired breathing,” say the researchers in their conference paper.

“Our findings so far thus point at vagus nerve dysfunction as a central pathophysiological feature of long COVID.”