What’s New in Infectious Disease?

On the brain. US researchers have conducted autopsies on patients that have died from COVID-19 to quantify the distribution and cell-type specificity of SARS-CoV-2 infection outside of the respiratory tract (1). The study found that virus replication was persistent not only in respiratory tissues but also non-respiratory tissues of the human body – including the brain – in early infection and up to 230 days after symptoms began. 

Urgent testing. Global testing rates in low and middle income countries have decreased after the onslaught of COVID-19 – reducing the effectiveness of SARS-CoV-2 genomic surveillance. New evidence reveals that low testing rates and spatiotemporal biases significantly delay the detection of new variants by months. To increase the productivity of genomic surveillance programs in these low to middle income countries, the mean test rate must increase to 100 tests per 100,000 persons per day (2).

Robotic revolution. Automation platforms greatly increase the productivity of global testing rates. A new technology that uses millimeter-sized magnets as mobile robotic agents – or ferrobots – allows the precise and accurate handling of magnetized sample droplets based on nucleic acid amplification. The method overcomes the limitations of pooled testing by enabling accessible, adaptable, and distributable automated viral testing (3).

Hook, line, and sinker. In a recent study, researchers have successfully leveraged DNA “nanobait” to detect nucleic acids from multiple respiratory viruses simultaneously (4). The sensing technology can be easily reprogrammed to discriminate between viral variants, rapidly identifying the presence of SARS-CoV-2 RNA variants in patient swabs with high specificity. In the future, researchers hope it can be implemented into point of care settings to allow amplification-free RNA identification.

In Other News
 

Ray of light. Quenchbody fluorescent immunosensors prove to be sensitive tools to rapidly diagnose COVID-19 – offering potential for high-throughput analysis of swab samples in large-scale monitoring of infectious diseases (5).

Building a blueprint. A genome assembly tool successfully sequenced the complete genome of the tuberculosis strain, H37Rv, using consensus building (6).

Culprit of long COVID? Exploratory study assessing the proteome, lipidome, and metabolome in patients with long COVID-19 syndrome finds that an exaggerated anti-inflammatory response may be responsible (7).

Scaling up. WHO guidelines suggest that simple biomarkers of liver fibrosis are not sensitive enough for hepatitis B diagnosis in sub-Saharan Africa. Researchers call for improved rule-in and rule-out thresholds to optimize treatment (8).

^{Credit: European Centre for Disease Prevention and Control / flickr.com}