Gargle pool PCR testing in a hospital during medium and high SARS-CoV-2 incidence.

BACKGROUND: Hospitals need to be protected from SARS-CoV-2 infections to protect vulnerable patients. Thus, a safe, efficient, and cost-effective SARS-CoV-2 testing system for hospitals, in addition to standard hygiene measures and vaccination of staff, is necessary. Here we report on the feasibility and performance of a pool real-time reverse-transcriptase polymerase-chain-reaction (rRT-PCR) test system at, medium and high incidence. METHODS: We implemented a testing concept based on gargling at home and pooling of samples in the hospital before PCR testing in the laboratory. We used two PCR systems (point of care and standard 96-well plate system) to adapt to challenges in the hospital setting and respond to a rising incidence in the Omicron wave. FINDINGS: During our 10-week study period, we performed 697 pool PCRs (8793 tests in total) and identified 65 asymptomatic staff members by pool PCR and 94 symptomatic staff members by positive individual PCR. Virus loads in those detected by pool testing were significantly lower (P<0.001). The test system remained workable even during the peak of the Omicron wave and no outbreaks occurred in any specific area of the hospital during the study period. Unvaccinated individuals were over-represented in the positively tested (37% vs 22% positive tests, P=0.04). The test procedure was well accepted by a majority of the hospital staff (84%). CONCLUSION: Repeated gargle pool rRT-PCR testing can be implemented quickly in hospitals and is an effective, easily adaptable and well-accepted test system for hospitals, even during phases with very high infection rates.

Childhood asthma is associated with mutations and gene expression differences of ORMDL genes that can interact.

BACKGROUND: Genomewide association studies identified ORMDL3 as a plausible asthma candidate gene. ORMDL proteins regulate sphingolipid metabolism and ceramide homeostasis and participate in lymphocyte activation and eosinophil recruitment. Strong sequence homology between the three ORMDL genes and ORMDL protein conservation among different species suggest that they may have shared functions. We hypothesized that if single nucleotide polymorphisms (SNPs) in ORMDL3 alter its gene expression and play a role in asthma, variants in ORMDL1 and ORMDL2 might also be associated with asthma. METHODS: Asthma associations of 44 genotyped SNPs were determined in at least 1303 subjects (651 asthmatics). ORMDL expression was evaluated in peripheral blood mononuclear cells (PBMC) from 55 subjects (eight asthmatics) before and after allergen stimulation, and in blood (n = 60, 5 asthmatics). Allele-specific cis-effects on ORMDL expression were assessed. Interactions between human ORMDL proteins were determined in living cells. RESULTS: Sixteen SNPs in all three ORMDLs were associated with asthma (14 in ORMDL3). Baseline expression of ORMDL1 (P = 1.7 × 10(-6) ) and ORMDL2 (P = 4.9 × 10(-5) ) was significantly higher in PBMC from asthmatics, while induction of ORMDLs upon stimulation was stronger in nonasthmatics. Disease-associated alleles (rs8079416, rs4795405, rs3902920) alter ORMDL3 expression. ORMDL proteins formed homo- and heterooligomers and displayed similar patterns of interaction with SERCA2 and SPT1. CONCLUSIONS: Polymorphisms in ORMDL genes are associated with asthma. Asthmatics exhibit increased ORMDL levels, suggesting that ORMDLs contribute to asthma. Formation of heterooligomers and similar interaction patterns with proteins involved in calcium homeostasis and sphingolipid metabolism could indicate shared biological roles of ORMDLs, influencing airway remodeling and hyperresponsiveness.