ABSTRACT
TRCReady® SARS-CoV-2 i is a reagent for transcription-reverse transcription concerted reaction (TRC) to detect SARS-CoV-2 N2 gene, used with the automated rapid isothermal nucleic acid amplification test (NAAT) analyzer TRCReady®-80. Sensitivity and specificity of TRCReady® SARS-CoV-2 i was assessed by comparison with the results of real-time reverse transcription-polymerase chain reaction (RT-PCR) using nasopharyngeal swab samples. From November 2020 to March 2021, a total of 441 nasopharyngeal swabs were obtained and analyzed both with TRCReady® SARS-CoV-2 i and RT-PCR. Sensitivity and specificity of TRCReady® SARS-CoV-2 i were 94.6% (53/56) and 99.2% (382/385), respectively. Reaction time to positivity of TRCReady® SARS-CoV-2 i ranged from 1.166 to 9.805 (median: 2.887) min, and minimum detection sensitivity of TRCReady® SARS-CoV-2 i was 9 copies per test, with reaction time as 5.014 min. Detection of SARS-CoV-2 gene from nasopharyngeal swab sample using TRCReady® SARS-CoV-2 i shows comparative diagnostic test accuracy with RT-PCR, and can be used as a useful test to diagnose SARS-CoV-2 infection. © 2022 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases
ABSTRACT
Bacterial drug resistance has become a global public health threat, among which the infection of carbapenem-resistant Enterobacterales (CRE) is one of the top noticeable issues in the global anti-infection area due to limited therapy options. In recent years, the prevalence of CRE transmission around the world has increased, and the transmission of COVID-19 has intensified the situation to a certain extent. CRE resistance can be induced by carbapenemase, porin, efflux pump, penicillin-binding protein alteration, and biofilm production. Deletion, mutation, insertion, and post-transcriptional modification of corresponding coding genes may affect the sensitivity of Enterobacterales bacteria to carbapenems. Clinical and laboratory methods to detect CRE and explore its resistance mechanisms are being developed. Due to the limited options of antibiotics, the clinical treatment of CRE infection also faces severe challenges. The clinical therapies of CRE include single or combined use of antibiotics, and some new antibiotics and treatment methods are also being developed. Hence, this review summarizes the epidemiology, resistance mechanisms, screening and clinical treatments of CRE infection, to provide references for clinical prevention, control and treatment of CRE infection. © 2022 Elsevier GmbH
ABSTRACT
The prevalence of porcine enteric coronaviruses (PECs), including transmissible gastroenteritis virus (TGEV), swine acute diarrhea syndrome coronavirus (SADS-CoV), porcine delta coronavirus (PDCoV), and porcine epidemic diarrhea virus (PEDV), poses a serious threat to animal and public health. Here, we aimed to further optimize the porcine aminopeptidase N (pAPN) gene editing strategy to explore the balance between individual antiviral properties and the biological functions of pAPN in pigs. Finally, APN-chimeric gene-edited pigs were produced through a CRISPR/Cas9-mediated knock-in strategy. Further reproductive tests indicated that these gene-edited pigs exhibited normal pregnancy rates and viability. Notably, in vitro viral challenge assays further demonstrated that porcine kidney epithelial cells isolated from F1-generation gene-edited pigs could effectively inhibit TGEV infection. This study is the first to report the generation of APN-chimeric pigs, which may provide a natural host animal for characterizing PEC infection with APN and help in the development of better antiviral solutions. © 2022 Elsevier B.V.
ABSTRACT
Here, we introduce a power-free foldable poly(methyl methacrylate) (PMMA) microdevice fully integrating DNA extraction, amplification, and visual detection, realized in novel dual modes – colorimetric and aggregate formation – using 4-Aminoantipyrine (4-AP) for monitoring pathogens. The microdevice contains two parts: reaction and detection zones. A sealing film was utilized to connect the two zones and make the device foldable. The FTA card was deposited in the reaction zone for DNA extraction, followed by loop-mediated isothermal amplification (LAMP) at 65 °C for 45 min. When the detection zone is folded toward the reaction zone, paper discs modified with 4-AP placed in the detection zone are delivered to the reaction zone. Specifically, in the presence of LAMP amplicons, 4-AP is oxidized into antipyrine red or generates aggregates by interacting with copper sulfate, forming copper hybrid nanostructure (Cu-hNs). In the absence of LAMP amplicons, 4-AP is not oxidized and maintains yellow color or fails to form aggregates. Furthermore, we introduced the ethidium homodimer-1 (EthD-1) to identify viable bacteria. EthD-1 penetrated the compromised membranes of nonviable cells and prevented further DNA amplification by intercalating with the DNA. In this way, only samples containing viable cells displayed color change or formed aggregates upon reaction with 4-AP. Using this method, SARS-CoV-2 RNA and Enterococcus faecium were identified by naked eye, with the limit of detection of 103 copies/μL and 102 CFU/mL, respectively, within 60 min. The introduced microdevice can be used for rapidly monitoring viable pathogens and controlling outbreaks of infectious disease in resource-limited settings. © 2022 Elsevier B.V.
ABSTRACT
Highly mutable pathogens pose daunting challenges for antibody design. The usual criteria of high potency and specificity are often insufficient to design antibodies that provide long-lasting protection. This is due, in part, to the ability of the pathogen to rapidly acquire mutations that permit them to evade the designed antibodies. To overcome these limitations, design of antibodies with a larger neutralizing breadth can be pursued. Such broadly neutralizing antibodies (bnAbs) should remain targeted to a specific epitope, yet show robustness against pathogen mutability, thereby neutralizing a higher number of antigens. This is particularly important for highly mutable pathogens, like the influenza virus and the human immunodeficiency virus (HIV). The protocol describes a method for computing the "breadth” of a given antibody, an essential aspect of antibody design. © 2023, Springer Science+Business Media, LLC, part of Springer Nature.
ABSTRACT
Introduction: The objective of this study was to compare the numeric cut-off index (COI) of automated antigen tests with the cycle-threshold (Ct) value. Materials and methods: COI values of all samples processed with the Elecsys® SARS-CoV-2 Antigen (Roche, Switzerland) from January to February 2022 were retrieved and the positive were compared to RdRP Cts of Allplex Variants I (Seegene, Korea). COI between 0.6 and 1 were considered indeterminate and overproved by RT-PCR. Results: From 13,937 samples 7944(57%) were positive and 189(1.35%) indeterminate. There was a strong correlation between Cts and COI values at the positive samples, but that was not the case for indeterminates. Conclusions: COI values of the positive samples (COI >1) are comparable to Ct values and may therefore be used as proxy viral loads, however this is not the case for indeterminate samples. © 2022 Elsevier Inc.
ABSTRACT
Individuals infected with the SARS-CoV-2 virus present with a wide variety of symptoms ranging from asymptomatic to severe and even lethal outcomes. Past research has revealed a genetic haplotype on chromosome 3 that entered the human population via introgression from Neanderthals as the strongest genetic risk factor for the severe response to COVID-19. However, the specific variants along this introgressed haplotype that contribute to this risk and the biological mechanisms that are involved remain unclear. Here, we assess the variants present on the risk haplotype for their likelihood of driving the genetic predisposition to severe COVID-19 outcomes. We do this by first exploring their impact on the regulation of genes involved in COVID-19 infection using a variety of population genetics and functional genomics tools. We then perform a locus-specific massively parallel reporter assay to individually assess the regulatory potential of each allele on the haplotype in a multipotent immune-related cell line. We ultimately reduce the set of over 600 linked genetic variants to identify four introgressed alleles that are strong functional candidates for driving the association between this locus and severe COVID-19. Using reporter assays in the presence/absence of SARS-CoV-2, we find evidence that these variants respond to viral infection. These variants likely drive the locus' impact on severity by modulating the regulation of two critical chemokine receptor genes: CCR1 and CCR5. These alleles are ideal targets for future functional investigations into the interaction between host genomics and COVID-19 outcomes.
Subject(s)
COVID-19 , Neanderthals , Virus Diseases , Humans , Animals , COVID-19/genetics , Neanderthals/genetics , SARS-CoV-2/genetics , Genetics, PopulationABSTRACT
Recently, several studies have highlighted a skewed prevalence of infectious diseases within the African continent. Furthermore, a growing number of studies have demonstrated unique genetic variants found within the African genome are one of the contributing factors to the disease severity of infectious diseases within Africa. Understanding the host genetic mechanisms that offer protection against infectious diseases provides an opportunity to develop unique therapeutic interventions. Over the past two decades, several studies have linked the 2'-5'-oligoadenylate synthetase (OAS) family with a range of infectious diseases. More recently, the OAS-1 gene has also been associated with disease severity caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which led to a global pandemic. The OAS family serves as an antiviral factor through the interaction with Ribonuclease-Latent (RNase-L). This review explores the genetic variants observed within the OAS genes and the associations with various viral infections and how previously reported ethnic-specific polymorphisms drive clinical significance. This review provides an overview of OAS genetic association studies with a particular focus on viral diseases affecting individuals of African descent.
Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Adenine Nucleotides , OligoribonucleotidesABSTRACT
Porcine epidemic diarrhea virus (PEDV), a continuously evolving pathogen, causes severe diarrhea in piglets, with high mortality rates. To prevent or mitigate the disease, it is common practice to develop live or inactivated PEDV vaccines based on cell-adapted viral variants. Propagating wild-type PEDV in cultured cells is, however, often challenging due to the lack of knowledge about the requirements for the cell adaptation of PEDV. In the present study, by using the RNA-targeted reverse genetic system for PEDV to apply S protein swapping followed by the rescue of the recombinant viruses, three key amino acid mutations in the S protein, A605E, E633Q, and R891G, were identified, which enable attenuated PEDV strain DR13 (DR13att) to efficiently and productively infect Vero cells, in contrast to the parental DR13 strain (DR13par). The former two key mutations reside inside and in the vicinity of the receptor binding domain (RBD), respectively, while the latter occurs at the N-terminal end of the fusion peptide (FP). Besides the three key mutations, other mutations in the S protein further enhanced the infection efficiency of the recombinant viruses. We hypothesize that the three mutations changed PEDV tropism by altering the S2' cleavage site and the RBD structure. This study provides basic molecular insight into cell adaptation by PEDV, which is also relevant for vaccine design. IMPORTANCE Porcine epidemic diarrhea virus (PEDV) is a lethal pathogen for newborn piglets, and an efficient vaccine is needed urgently. However, propagating wild-type PEDV in cultured cells for vaccine development is still challenging due to the lack of knowledge about the mechanism of the cell adaptation of PEDV. In this study, we found that three amino acid mutations, A605E, E633Q, and R891G, in the spike protein of the Vero cell-adapted PEDV strain DR13att were critical for its cell adaptation. After analyzing the mutation sites in the spike protein, we hypothesize that the cell adaptation of DR13att was achieved by altering the S2' cleavage site and the RBD structure. This study provides new molecular insight into the mechanism of PEDV culture adaptation and new strategies for PEDV vaccine design.
Subject(s)
Coronavirus Infections , Coronavirus , Porcine epidemic diarrhea virus , Swine Diseases , Chlorocebus aethiops , Animals , Swine , Vero Cells , Porcine epidemic diarrhea virus/genetics , Coronavirus/genetics , Spike Glycoprotein, Coronavirus/genetics , Amino Acid Substitution , Coronavirus Infections/veterinary , Coronavirus Infections/genetics , Swine Diseases/prevention & controlABSTRACT
Tea ingredients can effectively inhibit SARS-CoV-2 infection at adequate concentrations. It is not known whether tea intake could impact the susceptibility to COVID-19 or its severity. We aimed to evaluate the causal effects of tea intake on COVID-19 outcomes. We performed Mendelian randomization (MR) analyses to assess the causal associations between tea intake (N = 441,279) and three COVID-19 outcomes, including SARS-CoV-2 infection (122,616 cases and 2,475,240 controls), hospitalized COVID-19 (32,519 cases and 2,062,805 controls), and critical COVID-19 (13,769 cases and 1,072,442 controls). The MR analyses indicated that genetic propensity for tea consumption conferred a negative causal effect on the risk of SARS-CoV-2 infection (OR: 0.87, 95% confidence interval (CI): 0.78-0.97, P = 0.015). No causal effects on hospitalized COVID-19 (0.84, 0.64-1.10, P = 0.201) or critical COVID-19 (0.73, 0.51-1.03, P = 0.074) were detected. Our study revealed that tea intake could decrease the risk of SARS-CoV-2 infection, highlighting the potential preventive effect of tea consumption on COVID-19 transmission.
ABSTRACT
Coronavirus Disease (COVID-19) may cause a dysregulation of the immune system and has complex relationships with multiple autoimmune diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). However, little is known about their common genetic architecture. Using the latest data from COVID-19 host genetics consortium and consortia on RA and SLE, we conducted a genome-wide cross-trait analysis to examine the shared genetic etiology between COVID-19 and RA/SLE and evaluated their causal associations using bidirectional Mendelian randomization (MR). The cross-trait meta-analysis identified 23, 28, and 10 shared genetic loci for severe COVID-19, COVID-19 hospitalization, and SARS-CoV-2 infection with RA, and 14, 17, and 7 shared loci with SLE, respectively. Co-localization analysis identified five causal variants in TYK2, IKZF3, PSORS1C1, and COG6 for COVID-19 with RA, and four in CRHR1, FUT2, and NXPE3 for COVID-19 with SLE, involved in immune function, angiogenesis and coagulation. Bidirectional MR analysis suggested RA is associated with a higher risk of COVID-19 hospitalization, and COVID-19 is not related to RA or SLE. Our novel findings improved the understanding of the genetic etiology shared by COVID-19, RA and SLE, and suggested an increased risk of COVID-19 hospitalization in people with higher genetic liability to RA.
Subject(s)
Arthritis, Rheumatoid , COVID-19 , Lupus Erythematosus, Systemic , Humans , Mendelian Randomization Analysis , COVID-19/complications , SARS-CoV-2/genetics , Genome-Wide Association Study , Polymorphism, Single NucleotideABSTRACT
Brunner gland lesions (BGLs) encompass benign proliferations of the homonymous glands and have been designated as hyperplasia, adenoma (BGA), hamartoma or nodule. In general terms, lesions larger than 0.5 cm are considered true neoplasia with unknown malignant potential and unclear pathogenesis. Genetic alterations have seldom been reported in BGL, and include SMAD4/DPC4 and LRIG1, but not KRAS (Kirsten rat sarcoma viral oncogene homologue) to the best of our knowledge.We present the case of a man in his 60s, evaluated for iron deficiency anaemia harbouring a 1.5 cm BGA found by duodenoscopy. Immunohistochemistry failed to reveal microsatellite instability, and next-generation sequencing revealed a KRAS G12D point mutation.
Subject(s)
Adenoma , Brunner Glands , Duodenal Neoplasms , Humans , Brunner Glands/pathology , Duodenal Neoplasms/genetics , Duodenal Neoplasms/pathology , Duodenoscopy , Mutation , Adenoma/diagnostic imaging , Adenoma/genetics , Adenoma/pathology , Proto-Oncogene Proteins p21(ras)/geneticsABSTRACT
The impact of COVID-19 pandemic on smallholder farming households (SFH) includes increased poverty, and loss of livelihoods. Provision of livestock to SFH is a helpful intervention to mitigate this impact. This study provided a total of 150 smallholder poultry farmers, randomly selected from three states (Kebbi, Nasarawa, and Imo) in Nigeria, with ten 5-week-old chickens (mixed sexes) each, of either FUNAAB Alpha or Noiler chicken genetics. The improved, dual-purpose chickens were evaluated for growth performance (GP), survivability and profitability. The birds were managed under semi-scavenging production system. Body weight, mortality, and cost of production (COP) were recorded every 4 weeks until 21 weeks of age. Profitability was a function of the COP, and the selling price for live-birds (cocks). Body weight of Noiler (1,927 g) birds was not significantly (p > .05) higher than FUNAAB Alpha (1,792 g) at 21 weeks. Agroecology and genetics had significant (p < .05) effects on GP and survivability. Survivability of FUNAAB Alpha was higher (p < .05) than Noiler, with Nasarawa (81%-96%), having the highest (p < .0001) survival rate compared to Imo (62%-81%), and Kebbi (58%-75%). At 21 weeks, the number of cocks and hens differed significantly (p < .05) within the states (Imo: 2.4 ± .2 and 5.4 ± .3; Kebbi: 2.6 ± .2 and 5.5 ± .3; and Nasarawa: 2.9 ± .2 and 5.8 ± .3). Nasarawa (NGN 7,808; USD 19) ranked best for profitability, followed by Kebbi (NGN 6,545; USD 16) and Imo (NGN 5,875; USD 14). Overall, this study demonstrates that provision of improved chickens to vulnerable SFH in Nigeria holds great potential for economic growth, and resilience during emergencies, such as the COVID-19 pandemic.
ABSTRACT
OBJECTIVES: COVID-19 research has significantly contributed to pandemic response and the enhancement of public health capacity. COVID-19 data collected by provincial/territorial health authorities in Canada are valuable for research advancement yet not readily available to the public, including researchers. To inform developments in public health data-sharing in Canada, we explored Canadians' opinions of public health authorities sharing deidentified individual-level COVID-19 data publicly. DESIGN/SETTING/INTERVENTIONS/OUTCOMES: A national cross-sectional survey was administered in Canada in March 2022, assessing Canadians' opinions on publicly sharing COVID-19 datatypes. Market research firm Léger was employed for recruitment and data collection. PARTICIPANTS: Anyone greater than or equal to 18 years and currently living in Canada. RESULTS: 4981 participants completed the survey with a 92.3% response rate. 79.7% were supportive of provincial/territorial authorities publicly sharing deidentified COVID-19 data, while 20.3% were hesitant/averse/unsure. Datatypes most supported for being shared publicly were symptoms (83.0% in support), geographical region (82.6%) and COVID-19 vaccination status (81.7%). Datatypes with the most aversion were employment sector (27.4% averse), postal area (26.7%) and international travel history (19.7%). Generally supportive Canadians were characterised as being ≥50 years, with higher education, and being vaccinated against COVID-19 at least once. Vaccination status was the most influential predictor of data-sharing opinion, with respondents who were ever vaccinated being 4.20 times more likely (95% CI 3.21 to 5.48, p=0.000) to be generally supportive of data-sharing than those unvaccinated. CONCLUSIONS: These findings suggest that the Canadian public is generally favourable to deidentified data-sharing. Identifying factors that are likely to improve attitudes towards data-sharing are useful to stakeholders involved in data-sharing initiatives, such as public health agencies, in informing the development of public health communication and data-sharing policies. As Canada progresses through the COVID-19 pandemic, and with limited testing and reporting of COVID-19 data, it is essential to improve deidentified data-sharing given the public's general support for these efforts.
Subject(s)
COVID-19 , Humans , Cross-Sectional Studies , Public Opinion , Pandemics , COVID-19 Vaccines , CanadaABSTRACT
SARS-CoV-2 has adapted in a stepwise manner, with multiple beneficial mutations accumulating in a rapid succession at origins of VOCs, and the reasons for this are unclear. Here, we searched for coordinated evolution of amino acid sites in the spike protein of SARS-CoV-2. Specifically, we searched for concordantly evolving site pairs (CSPs) for which changes at one site were rapidly followed by changes at the other site in the same lineage. We detected 46 sites which formed 45 CSP. Sites in CSP were closer to each other in the protein structure than random pairs, indicating that concordant evolution has a functional basis. Notably, site pairs carrying lineage defining mutations of the four VOCs that circulated before May 2021 are enriched in CSPs. For the Alpha VOC, the enrichment is detected even if Alpha sequences are removed from analysis, indicating that VOC origin could have been facilitated by positive epistasis. Additionally, we detected nine discordantly evolving pairs of sites where mutations at one site unexpectedly rarely occurred on the background of a specific allele at another site, for example on the background of wild-type D at site 614 (four pairs) or derived Y at site 501 (three pairs). Our findings hint that positive epistasis between accumulating mutations could have delayed the assembly of advantageous combinations of mutations comprising at least some of the VOCs.
Subject(s)
Amino Acids , Evolution, Molecular , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Alleles , Mutation , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/geneticsABSTRACT
Bile acid synthetic disorders are rare inborn errors of metabolism, and presentations include neonatal cholestasis, neurological disease or deficiency of fat-soluble vitamins. Affected patients fail to produce standard bile acids but accumulate unusual bile acids and intermediates, resulting in liver failure and complications. Most of them improve with bile acid supplementation, but delaying initiating treatment is detrimental to the outcome.A young child presented to us with recurrent episodes of acute liver failure. In the first episode, both coagulopathy and encephalopathy improved on supportive treatment, but the aetiological evaluation was inconclusive. During the second presentation, whole-exome sequencing was sent, identifying a compound heterozygous novel mutation in the 3-ß-hydroxysteroid dehydrogenase type 7 gene leading to bile acid synthetic defect.
Subject(s)
Cholestasis , Liver Failure, Acute , Liver Failure , Child , Humans , Child, Preschool , Infant, Newborn , Bile Acids and Salts , MutationABSTRACT
OBJECTIVE: INGR1D (INvestigating Genetic Risk for type 1 Diabetes) was a type 1 diabetes (T1D) genetic screening study established to identify participants for a primary prevention trial (POInT, Primary Oral Insulin Trial). METHODS: The majority of participants were recruited by research midwives in antenatal clinics from 18 weeks' gestation. Using the NHS Newborn Bloodspot Screening Programme (NBSP) infrastructure, participants enrolled in INGR1D had an extra sample taken from their day 5 bloodspot card sent for T1D genetic screening. Those at an increased risk of T1D were informed of the result, given education about T1D and the opportunity to take part in POInT. RESULTS: Between April 2018 and November 2020, 66% of women approached about INGR1D chose to participate. 15 660 babies were enrolled into INGR1D and 14 731 blood samples were processed. Of the processed samples, 157 (1%) had confirmed positive results, indicating an increased risk of T1D, of whom a third (n=49) enrolled into POInT (20 families were unable to participate in POInT due to COVID-19 lockdown restrictions). CONCLUSION: The use of prospective consent to perform personalised genetic testing on samples obtained through the routine NBSP represents a novel mechanism for clinical genetic research in the UK and provides a model for further population-based genetic studies in the newborn.
ABSTRACT
OBJECTIVES: Adiposity, smoking, and lower socioeconomic position (SEP) increase COVID-19 risk while the association of vitamin D, blood pressure, and glycemic traits in COVID-19 risk were less clear. Whether angiotensin-converting enzyme 2 (ACE2), the key receptor for SARS-CoV-2, mediates these associations has not been investigated. We conducted a Mendelian randomization study to assess the role of these exposures in COVID-19 and mediation by ACE2. METHODS: We extracted genetic variants strongly related to various exposures (vitamin D, blood pressure, glycemic traits, smoking, adiposity, and educational attainment [SEP proxy]), and ACE2 cis-variants from genome-wide association studies (GWAS, n ranged from 28 204 to 3 037 499) and applied them to GWAS summary statistics of ACE2 (n = 28 204) and COVID-19 (severe, hospitalized, and susceptibility, n ≤ 2 942 817). We used inverse variance weighted as the main analyses, with MR-Egger and weighted median as sensitivity analyses. Mediation analyses were performed based on product of coefficient method. RESULTS: Higher adiposity, lifetime smoking index, and lower educational attainment were consistently associated with higher risk of COVID-19 phenotypes while there was no strong evidence for an association of other exposures in COVID-19 risk. ACE2 partially mediates the detrimental effects of body mass index (ranged from 4.3% to 8.2%), waist-to-hip ratio (ranged from 11.2% to 16.8%), and lower educational attainment (ranged from 4.0% to 7.5%) in COVID-19 phenotypes while ACE2 did not mediate the detrimental effect of smoking. CONCLUSIONS: We provided genetic evidence that reducing ACE2 could partly lower COVID-19 risk amongst people who were overweight/obese or of lower SEP.
ABSTRACT
The initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants, BA.1 and BA.2, are being progressively displaced by BA.5 in many countries. To provide insight on the replacement of BA.2 by BA.5 as the dominant SARS-CoV-2 variant, we performed a comparative analysis of Omicron BA.2.12.1 and BA.5.2 variants in cell culture and hamster models. We found that BA.5.2 exhibited enhanced replicative kinetics over BA.2.12.1 in vitro and in vivo, which is evidenced by the dominant BA.5.2 viral genome detected at different time points, regardless of immune selection pressure with vaccine-induced serum antibodies. Utilizing reverse genetics, we constructed a mutant SARS-CoV-2 carrying spike F486V substitution, which is an uncharacterized mutation that concurrently discriminates Omicron BA.5.2 from BA.2.12.1 variant. We noticed that the 486th residue does not confer viral replication advantage to the virus. We also found that 486V displayed generally reduced immune evasion capacity when compared with its predecessor, 486F. However, the surge of fitness in BA.5.2 over BA.2.12.1 was not due to stand-alone F486V substitution but as a result of the combination of multiple mutations. Our study upholds the urgency for continuous monitoring of SARS-CoV-2 Omicron variants with enhanced replication fitness.
ABSTRACT
AIM: The New South Wales (NSW) biochemical genetics (BG) service in Australia developed business continuity plans (BCPs) in response to the COVID-19 pandemic to ensure the essential service remained operational. This article aims to discuss the effects of the COVID-19 BCPs on the NSW BG service and patient care. METHODS: BCPs were developed that included charting of NSW BG service workflow and services against staff resources and clinical impact on patients. The effect of the BCPs was analysed quantitatively by reviewing key performance indicators (result turnaround time, frequency and severity of clinical incidents and laboratory nonconformities) and qualitatively from staff feedback generated by a BG laboratory-wide survey. RESULTS: Alternative BCPs were implemented during the pre-defined period March 2020 to November 2021 (inclusive), to reflect changes in COVID-19 community transmission, vaccination rates; and health orders. Operation of our essential pathology service was maintained, with no significant difference observed in key performance indicators when compared to pre-COVID. During the pre-defined period of the COVID-19 pandemic, staff reported increased levels of both work- and out-of-work-related stress. CONCLUSION: The successful continuation of the BG service, with no statistically significant impact on patient care and delivery of essential services, can be attributed to strategic planning and timely implementation of these BCPs. In conjunction with the resilient and robust attitude of the staff during this ever-changing situation, this experience has served as an invaluable tool for future disaster management planning.