Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 during Border Quarantine and Air Travel, New Zealand (Aotearoa).

The strategy in New Zealand (Aotearoa) to eliminate coronavirus disease requires that international arrivals undergo managed isolation and quarantine and mandatory testing for severe acute respiratory syndrome coronavirus 2. Combining genomic and epidemiologic data, we investigated the origin of an acute case of coronavirus disease identified in the community after the patient had spent 14 days in managed isolation and quarantine and had 2 negative test results. By combining genomic sequence analysis and epidemiologic investigations, we identified a multibranched chain of transmission of this virus, including on international and domestic flights, as well as a probable case of aerosol transmission without direct person-to-person contact. These findings show the power of integrating genomic and epidemiologic data to inform outbreak investigations.

Genomic Evidence of In-Flight Transmission of SARS-CoV-2 Despite Predeparture Testing.

Since the first wave of coronavirus disease in March 2020, citizens and permanent residents returning to New Zealand have been required to undergo managed isolation and quarantine (MIQ) for 14 days and mandatory testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). As of October 20, 2020, of 62,698 arrivals, testing of persons in MIQ had identified 215 cases of SARS-CoV-2 infection. Among 86 passengers on a flight from Dubai, United Arab Emirates, that arrived in New Zealand on September 29, test results were positive for 7 persons in MIQ. These passengers originated from 5 different countries before a layover in Dubai; 5 had negative predeparture SARS-CoV-2 test results. To assess possible points of infection, we analyzed information about their journeys, disease progression, and virus genomic data. All 7 SARS-CoV-2 genomes were genetically identical, except for a single mutation in 1 sample. Despite predeparture testing, multiple instances of in-flight SARS-CoV-2 transmission are likely.

Biofilm Inhibition via Delivery of Novel Methylthioadenosine Nucleosidase Inhibitors from PVA-Tyramine Hydrogels while Supporting Mesenchymal Stromal Cell Viability.

The rise of antibiotic resistance, coupled with increased expectations for mobility in later life, is creating a need for biofilm inhibitors and delivery systems that will reduce surgical implant infection. A limitation of some of these existing delivery approaches is toxicity exhibited toward host cells. Here, we report the application of a novel inhibitor of the enzyme, methylthioadenosine nucleosidase (MTAN), a key enzyme in bacterial metabolic pathways, which include S-adenosylmethionine catabolism and purine nucleotide recycling, in combination with a poly(vinyl alcohol)-tyramine-based (PVA-Tyr) hydrogel delivery system. We demonstrate that a lead MTAN inhibitor, selected from a screened library of 34 candidates, (2S)-2-(4-amino-5H-pyrrolo3,2-dpyrimidin-7-ylmethyl)aminoundecan-1-ol (31), showed a minimum biofilm inhibitory concentration of 2.2 ± 0.4 µM against a clinical staphylococcal species isolated from an infected implant. We observed that extracellular DNA, a key constituent of biofilms, is significantly reduced when treated with 10 µM compound 31, along with a decrease in biofilm thickness. Compound 31 was incorporated into a hydrolytically degradable photo-cross-linked PVA-Tyr hydrogel and the release profile was evaluated by HPLC studies. Compound 31 released from the PVA-hydrogel system significantly reduced biofilm formation (77.2 ± 8.4% biofilm inhibition). Finally, compound 31 released from PVA-Tyr showed no negative impact on human bone marrow stromal cell (MSC) viability, proliferation, or morphology. The results demonstrate the potential utility of MTAN inhibitors in treating infections caused by Gram-positive bacteria, and the development of a nontoxic release system that has potential for tunability for time scale of delivery.