Effect of colorectal cancer screening on colorectal cancer surgery outcomes: nationwide cohort study

BACKGROUND

National colorectal cancer screening commenced in Denmark in 2014. Little is known about the effects of organized colorectal cancer screening on intraoperative and postoperative events. The aim of this nationwide cohort study was to evaluate the difference in intraoperative and postoperative outcomes between patients with screen-detected colorectal cancer and non-screen-detected colorectal cancer within the first 90 days after surgery.

METHODS

National register data were collected for Danish residents diagnosed with colorectal cancer between January 2014 and March 2018. Outcomes for the two cohorts were reported as relative risk or weighted mean difference. Intraoperative outcomes were blood loss, blood transfusion, tumour perforation, and organ lesion. Postoperative outcomes were complications (surgical and non-surgical) and 90-day mortality. Discrete data estimates were calculated from a general linear model. Analyses were adjusted for potential healthy user bias with respect to sex, age, location of the cancer (colon/rectum), and Charlson co-morbidity index.

RESULTS

In total, 10 606 patients were included. Compared with patients in the non-screen-detected colorectal cancer group (4497 patients), patients in the screen-detected colorectal cancer group (6109 patients) had reduced intraoperative blood loss (-52 mL, 95% c.i. -67 to -37, P < 0.001), a shorter duration of hospitalization (-2.3 days, 95% c.i. -2.8 to -1.8, P < 0.001), and reduced rates of intraoperative organ lesion (0.76, 95% c.i. 0.59 to 0.99, P = 0.042), surgical complications (0.79, 95% c.i. 0.73 to 0.87, P < 0.001), non-surgical complications (0.68, 95% c.i. 0.60 to 0.78, P < 0.001), and 90-day mortality (0.29, 95% c.i. 0.21 to 0.39, P < 0.001).

CONCLUSION

In comparison with non-screen-detected colorectal cancer, surgery for screen-detected colorectal cancer remains associated with improvement in several intraoperative and early postoperative outcomes after considering healthy user bias.

Drug survival of biologic therapies for palmoplantar pustulosis: A nationwide study

BACKGROUND

Biological therapies have established efficacy in psoriasis vulgaris. However, palmoplantar pustulosis (PPP) has proven difficult to treat, and data on drug survival in these patients remain scarce.

OBJECTIVE

To investigate drug survival of biological treatments in a nationwide cohort of patients with PPP.

METHODS

We included all patients treated for PPP with a biologic from a prospective Danish nationwide registry between 2007 and 2019. Descriptive statistics were reported. Drug survival was calculated for all patients and specified for the most frequently used biologics. Drug survival was reported as median time to discontinuation. Kaplan-Meier plots were used to visualize drug survival. Trajectories of Dermatology Life Quality Index (DLQI) scores were plotted by interpolating between the different visits with a dermatologist for each treatment course.

RESULTS

We identified 85 individual patients who received biological therapy for PPP across 194 treatment courses during follow-up. Of the included treatment courses, 151 (77.8%) were discontinued. The most frequent cause of discontinuation was ineffective response to treatment (54.3%), while 18.5% of courses were discontinued due to adverse events. The median drug survival across all therapies for PPP was 9.3 (Inter quartile range (IQR), 3.9-25.6) months. Ustekinumab demonstrated the longest median time to discontinuation of 14.6 (IQR, 9.1-51.8) months. The proportion of bio-naive patients in treatment at 12 months were according to drug 47.9% for adalimumab, 64.3% for ustekinumab and 40.0% for secukinumab. For bio-experienced, it was 58.2% adalimumab, 54.5% for ustekinumab and 51.4% for secukinumab.

CONCLUSIONS

The treatment of PPP poses significant challenges, with limited drug survival observed across all therapies regardless of prior experience with biologics. Ustekinumab demonstrated the longest median drug survival. Notably, patients discontinuing therapy due to inefficacy exhibited higher DLQI scores, highlighting the importance of personalized treatment selection and timely consideration of therapy changes when inefficacy is established.

Treatment of patients with screen-detected colorectal cancer is less strenuous: a nationwide cohort study with long-term follow-up

OBJECTIVE

During the last two decades, organised colorectal cancer (CRC) screening has been widely implemented. It remains to be established if screen-detected CRC (SD-CRC) is associated with reduced long-term requirements for treatment as compared with patients with non-screen-detected CRC (NSD-CRC).

STUDY DESIGN AND METHODS

This nationwide cohort study evaluated differences in treatment and healthcare contacts from the date of diagnosis to two years after comparing patients with SD-CRC and NSD-CRC. Data were collected from national healthcare registers, including patients aged 50-75 years and diagnosed with CRC between January 1st 2014 and March 31st 2018. Analyses were stratified into UICC stages and adjusted for sex, 5-year age groups, type of cancer (colonic/rectal), and Charlson comorbidity index score to address healthy user bias.

RESULTS

In total, 12,040 patients were included, 4708 with SD-CRC and 7332 with NSD-CRC. In patients with SD-CRC, the duration of hospitalisation and rate of emergency surgery were reduced by 38 % (relative risk [RR] = 0.62) and 66 % (RR = 0.34), respectively. Moreover, this group was characterised by a 75 % reduction in oncological outpatient visits (RR = 0.35) and a reduced number of treatments with chemotherapy (RR = 0.57) and radiotherapy (RR = 0.50). There were no significant differences between the two populations in the rates of metastasectomy and the number of contacts with primary healthcare providers.

CONCLUSION

Compared to patients with NSD-CRC, patients with SD-CRC experience less hospitalisation and treatment within the first two years after diagnosis.

Effects of phenylephrine on systemic and cerebral circulations in humans: a systematic review with mechanistic explanations

We conducted a systematic review of the literature reporting phenylephrine-induced changes in blood pressure, cardiac output, cerebral blood flow and cerebral tissue oxygen saturation as measured by near-infrared spectroscopy in humans. We used the proportion change of the group mean values reported by the original studies in our analysis. Phenylephrine elevates blood pressure whilst concurrently inducing a reduction in cardiac output. Furthermore, despite increasing cerebral blood flow, it decreases cerebral tissue oxygen saturation. The extent of phenylephrine's influence on cardiac output (r = -0.54 and p = 0.09 in awake humans; r = -0.55 and p = 0.007 in anaesthetised humans), cerebral blood flow (r = 0.65 and p = 0.002 in awake humans; r = 0.80 and p = 0.003 in anaesthetised humans) and cerebral tissue oxygen saturation (r = -0.72 and p = 0.03 in awake humans; r = -0.24 and p = 0.48 in anaesthetised humans) appears closely linked to the magnitude of phenylephrine-induced blood pressure changes. When comparing the effects of phenylephrine in awake and anaesthetised humans, we found no evidence of a significant difference in cardiac output, cerebral blood flow or cerebral tissue oxygen saturation. There was also no evidence of a significant difference in effect on systemic and cerebral circulations whether phenylephrine was given by bolus or infusion. We explore the underlying mechanisms driving the phenylephrine-induced cardiac output reduction, cerebral blood flow increase and cerebral tissue oxygen saturation decrease. Individualised treatment approaches, close monitoring and consideration of potential risks and benefits remain vital to the safe and effective use of phenylephrine in acute care.

SARS-CoV-2 Variants BQ.1 and XBB.1.5 in Wastewater of Aircraft Flying from China to Denmark, 2023

We analyzed wastewater samples from 14 aircraft arriving in Denmark directly from China during January 9-February 12, 2023. Wastewater from 11 aircraft was SARS-CoV-2-positive by PCR; 6 predominantly contained BQ.1 and XBB.1 subvariants. Wastewater-based surveillance can contribute to public health monitoring of SARS-CoV-2 and other emerging infectious agents.

Less Invasive Primary Treatment for Colorectal Cancer After Implementation of National Screening: A Nationwide Cohort Study

BACKGROUND

The effect of organized colorectal cancer (CRC) screening on type of primary treatment remains sparsely investigated. This study evaluated the difference in primary treatment strategy between patients diagnosed with screen-detected (SD-CRC) and non-screen-detected colorectal cancer (NSD-CRC) in a national CRC screening program.

METHODS

This was a retrospective national register-based cohort study. Data on patients aged between 50 and 75 years and diagnosed with SD-CRC or NSD-CRC were retrieved from the national colorectal cancer screening database and the Danish Colorectal Cancer Group database. Outcomes related to surgical invasiveness were compared between the two cohorts. Differences were expressed as relative risks using log-binomial generalized linear regression models. UICC stage IV specific outcomes were analyzed using the same method. All analyses were adjusted for sex, age, type of cancer (colonic/rectal), and Charlson comorbidity index.

RESULTS

The study included 4707 patients with SD-CRC and 7328 with NSD-CRC. Therapeutic flexible endoscopy (SD-CRC: n = 636 vs. NSD-CRC: n = 334, RR: 2.50, P < 0.001), (robotic-assisted) laparoscopic resection ((n = 616 vs. n = 773, RR: 1.27, P < 0.001), n = 2759 vs. n = 3471, RR: 1.11, P < 0.001), and radical resection (n = 3890 vs. n = 4834, RR: 1.02, P = 0.002) were significantly more frequent in the SD-CRC group. The rates of emergency priority (n = 32 vs. n = 562, RR: 0.09, P < 0.001), open surgery (n = 391 vs. n = 1410, RR: 0.53, P < 0.001), supplementary organ resection (n = 259 vs. n = 860, RR: 0.56, P < 0.001), and stoma formation (n = 526 vs. n = 1040, RR: 0.89, P = 0.007) were significantly lower in the SD-CRC group. The rate of patients undergoing surgery with UICC stage IV disease was significantly higher in the SD-CRC group (SD-CRC: n = 262, NSD-CRC: n = 994, RR: 1.43, P < 0.001).

CONCLUSION

SD-CRC remained associated with less invasive primary surgical treatment following adjustment for potential healthy user bias. UICC stage IV disease may be less advanced in patients with SD-CRC.

Combined endoscopic and laparoscopic surgery (CELS) for early colon cancer in high-risk patients

BACKGROUND

Local excision of early colon cancers could be an option in selected patients with high risk of complications and no sign of lymph node metastasis (LNM). The primary aim was to assess feasibility in high-risk patients with early colon cancer treated with Combined Endoscopic and Laparoscopic Surgery (CELS).

METHODS

A non-randomized prospective feasibility study including 25 patients with Performance Status score ≥ 1 and/or American Society of Anesthesiologists score ≥ 3, and clinical Union of International Cancer Control stage-1 colon cancer suitable for CELS resection. The primary outcome was failure of CELS resection, defined as either: Incomplete resection (R1/R2), local recurrence within 3 months, complication related to CELS within 30 days (Clavien-Dindo grade ≥ 3), death within 30 days or death within 90 days due to complications to surgery.

RESULTS

Fifteen patients with clinical T1 (cT1) and ten with clinical T2 (cT2) colon cancer and without suspicion of metastases were included. Failure occurred in two patients due to incomplete resections. Histopathological examination classified seven patients as having pT1, nine as pT2, six as pT3 adenocarcinomas, and three as non-invasive tumors. In three patients, the surgical strategy was changed intraoperatively to conventional colectomy due to tumor location or size. Median length of stay was 1 day. Seven patients had completion colectomy performed due to histological high-risk factors. None had LNM.

CONCLUSIONS

In selected patients, CELS resection was feasible, and could spare some patients large bowel resection.

First cases of SARS-CoV-2 BA.2.86 in Denmark, 2023

We describe 10 cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant BA.2.86 detected in Denmark, including molecular characteristics and results from wastewater surveillance that indicate that the variant is circulating in the country at a low level. This new variant with many spike gene mutations was classified as a variant under monitoring by the World Health Organization on 17 August 2023. Further global monitoring of COVID-19, BA.2.86 and other SARS-CoV-2 variants is highly warranted.

Barriers for Participation in the Danish Colorectal Cancer Screening Program: a Qualitative Study

PURPOSE

The participation rate in the Danish National Screening Program for Colorectal Cancer is around 60%. Since early detection of cancer through the colorectal cancer screening program (CRCS) reduces mortality rates, it is important to understand why people do not participate. The aim of this study was therefore to examine in depth why some people do not participate in the Danish CRCS program.

METHODS

Individual semi-structured interviews were conducted with 18 people who had not participated in the national CRCS program. Data was analyzed using an inductive hermeneutic approach.

RESULTS

The analysis uncovered three main themes describing barriers to screening: (a) the accountability for ensuring personal health covered the following sub-themes: (i) when invitation is out of sight it is out of mind, (ii) aversion against own stool sample collection, and (iii) the perceived risk of getting colorectal cancer (CRC); (b) attitudes towards the healthcare system and its organization covered the following sub-themes: (i) positivity towards CRCS, (ii) trust in the healthcare system, (iii) lack of internal communication in the healthcare system, and (iv) wish for involvement of the general practitioner (GP); (c) knowledge about disease and screening covered the following sub-themes: (i) knowledge about CRC and CRCS, (ii) wish for information via new channels, and (iii) CRC is rarely something you talk about.

CONCLUSION

Among the informants included in this study, lack of participation in the CRCS program was not due to an active opt-out, as most informants had intentions of participating. The informants thought it would motivate them to participate if their GP would remind them of the screening program.

The COVID-19 pandemic in Greenland, epidemic features and impact of early strict measures, March 2020 to June 2022

BackgroundThe COVID-19 pandemic was of major concern in Greenland. There was a high possibility of rapid transmission in settlements, and an increased risk of morbidity and mortality because of comorbidities in the population and limited access to specialised healthcare in remote areas.AimTo describe the epidemiology of the COVID-19 pandemic in Greenland and evaluate the effects of a strict COVID-19 strategy until risk groups were immunised.MethodsWe studied the epidemiology during March 2020 to June 2022. We describe the non-pharmaceutical interventions (NPIs), PCR-confirmed COVID-19 cases and vaccination coverage with data from the registries of the Greenlandic health authority.ResultsWe found 21,419 confirmed cases per 100,000 inhabitants (54% female, 46% male), 342 per 100,000 were hospitalised and 16 per 100,000 were admitted to the intensive care unit. The COVID-19 mortality rate was 39 per 100,000, all those affected were aged above 65 years. No excess overall mortality was observed. The vaccination coverage by June 2022 was 71.67 and 41% for one, two and three doses, respectively.ConclusionSARS-CoV-2 circulation in Greenland was low, given strict restrictions until all eligible inhabitants had been offered immunisation. The main impact of the pandemic was from May 2021 onwards with increasing numbers of confirmed cases. This occurred after introduction of the vaccine programme, which may have had an influence on the severity of the associated morbidity and mortality experienced. Halting community transmission of SARS-CoV-2 with NPIs until the majority of the population had been immunised was a successful strategy in Greenland.

The gold standard program (GSP) for smoking cessation: a cohort study of its effectiveness among smokers with and without cancer

BACKGROUND

Smoking cessation treatment is an important prognostic factor for survival after a cancer diagnosis, especially for tobacco-related cancers. After being diagnosed with lung cancer, approximately 50% of patients continue smoking or frequently relapse after a quit attempt. Given the importance of smoking cessation treatment for cancer survivors, the objective was to compare the effectiveness of a 6-week intensive smoking cessation intervention, the Gold Standard Program (GSP), among cancer survivors compared with smokers without cancer. Second, we compared successful quitting among socioeconomically disadvantaged cancer survivors with that among nondisadvantaged cancer survivors.

MATERIALS AND METHODS

This was a cohort study based on 38,345 smokers from the Danish Smoking Cessation Database (2006-2016). Linkage to the National Patient Register was used to identify cancer survivors undergoing the GSP after being diagnosed with cancer (except nonmelanoma skin cancer). Linkage to the Danish Civil Registration System was used to identify participants who died, went missing, or emigrated before the follow-up. Logistic regression models were applied to evaluate effectiveness.

RESULTS AND CONCLUSION

Six percent (2438) of the included smokers were cancer survivors at the time they undertook the GSP. Their 6-month successful quitting showed no difference compared to that of smokers without cancer, neither before nor after adjustment; 35% versus 37% in crude rates and an aOR of 1.13 (95% CI: 0.97-1.32). Likewise, the results for disadvantaged compared to nondisadvantaged cancer survivors were not significantly different (32% versus 33% and an adjusted aOR of 0.87 (95% CI 0.69-1.11)). Overall, an intensive smoking cessation program seems effective in helping both people without cancer and cancer survivors become successful quitters.

Characteristics of 86 individuals with mpox diagnosed at Copenhagen University Hospital

INTRODUCTION

Since the beginning of the mpox (previously called monkeypox) outbreak in 2022, almost half of cases in Denmark have been diagnosed at the Department of Infectious Diseases, Copenhagen University Hospital - Amager and Hvidovre Hospital. This article describes the patient cohort seen at the Department with a view to increasing knowledge of mpox among colleagues who are most likely to identify future cases.

METHODS

A retrospective observational study reporting patient characteristics, coinfections, clinical presentation and diagnostic delay among mpox cases diagnosed at the department between 23 May 2022 and 8 February 2023. Furthermore, a case report of a patient hospitalised with severe rectal pain is presented to highlight anorectal symptoms.

RESULTS

A total of 86 patients were diagnosed with mpox, all were men who have sex with men, with a median age of 39 years. Twenty-six patients (31%) took HIV pre-exposure prophylaxis, and 20 patients (24%) were people living with HIV. All patients (100%) presented with lesions, most frequently on or around the genitals. Twenty-nine patients (35%) had anorectal discomfort or pain. Seven patients (10%) had chlamydia, 19 (26%) gonorrhoea and two (5%) syphilis. In 13 cases (15%), mpox was not suspected at the first medical consultation, mainly because symptoms were attributed to a gonorrhoeal coinfection. Five patients (6%) were hospitalised for a median of three days.

CONCLUSION

As mpox may become endemic in Denmark, clinicians should remain aware of its symptoms and the risk of coinfection with sexually transmitted infections.

FUNDING

None.

TRIAL REGISTRATION

Not relevant.

Optimizing Screening for Colorectal Cancer: An Algorithm Combining Fecal Immunochemical Test, Blood-Based Cancer-Associated Proteins and Demographics to Reduce Colonoscopy Burden

BACKGROUND

Fecal Immunochemical Test (FIT) is widely used in population-based screening for colorectal cancer (CRC). This had led to major challenges regarding colonoscopy capacity. Methods to maintain high sensitivity without compromising the colonoscopy capacity are needed. This study investigates an algorithm that combines FIT result, blood-based biomarkers associated with CRC, and individual demographics, to triage subjects sent for colonoscopy among a FIT positive (FIT⁺) screening population and thereby reduce the colonoscopy burden.

MATERIALS AND METHODS

From the Danish National Colorectal Cancer Screening Program, 4048 FIT⁺ (≥100 ng/mL Hemoglobin) subjects were included and analyzed for a panel of 9 cancer-associated biomarkers using the ARCHITECT i2000. Two algorithms were developed: 1) a predefined algorithm based on clinically available biomarkers: FIT, age, CEA, hsCRP and Ferritin; and 2) an exploratory algorithm adding additional biomarkers: TIMP-1, Pepsinogen-2, HE4, CyFra21-1, Galectin-3, B2M and sex to the predefined algorithm. The diagnostic performances for discriminating subjects with or without CRC in the 2 models were benchmarked against the FIT alone using logistic regression modeling.

RESULTS

The discrimination of CRC showed an area under the curve (AUC) of 73.7 (70.5-76.9) for the predefined model, 75.3 (72.1-78.4) for the exploratory model, and 68.9 (65.5-72.2) for FIT alone. Both models performed significantly better (P < .001) than the FIT model. The models were benchmarked vs. FIT at cutoffs of 100, 200, 300, 400, and 500 ng/mL Hemoglobin using corresponding numbers of true positives and false positives. All performance metrics were improved at all cutoffs.

CONCLUSION

A screening algorithm including a combination of FIT result, blood-based biomarkers and demographics outperforms FIT in discriminating subjects with or without CRC in a screening population with FIT results above 100 ng/mL Hemoglobin.

Rapid and Flexible RT-qPCR Surveillance Platforms To Detect SARS-CoV-2 Mutations

Multiple mutations in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) increase transmission, disease severity, and immune evasion and facilitate zoonotic or anthropozoonotic infections. Four such mutations, ΔH69/V70, L452R, E484K, and N501Y, occurred in the SARS-CoV-2 spike glycoprotein in combinations that allow the simultaneous detection of VOCs. Here, we present two flexible reverse transcription-quantitative PCR (RT-qPCR) platforms for small- and large-scale screening (also known as variant PCR) to detect these mutations and schemes for adapting the platforms to future mutations. The large-scale RT-qPCR platform was validated by pairwise matching of RT-qPCR results with whole-genome sequencing (WGS) consensus genomes, showing high specificity and sensitivity. Both platforms are valuable examples of complementing WGS to support the rapid detection of VOCs. Our mutational signature approach served as an important intervention measure for the Danish public health system to detect and delay the emergence of new VOCs. IMPORTANCE Denmark weathered the SARS-CoV-2 crisis with relatively low rates of infection and death. Intensive testing strategies with the aim of detecting SARS-CoV-2 in symptomatic and nonsymptomatic individuals were available by establishing a national test system called TestCenter Denmark. This testing regime included the detection of SARS-CoV-2 signature mutations, with referral to the national health system, thereby delaying outbreaks of variants of concern. Our study describes the design of the large-scale RT-qPCR platform established at TestCenter Denmark in conjunction with whole-genome sequencing to report mutations of concern to the national health system. Validation of the large-scale RT-qPCR platform using paired WGS consensus genomes showed high sensitivity and specificity. For smaller laboratories with limited infrastructure, we developed a flexible small-scale RT-qPCR platform to detect three signature mutations in a single run. The RT-qPCR platforms are important tools to support the control of the SARS-CoV-2 endemic in Denmark.

Supplementation With Fish Oil in Pregnancy Reduces Gastroenteritis in Early Childhood

BACKGROUND

We hypothesized that insufficient intake of fish oil-derived omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFAs) during pregnancy is a contributing factor to gastroenteritis in early childhood. We examined the effect of n-3 LCPUFA supplementation on gastroenteritis symptoms in the offspring's first 3 years of life.

METHODS

This was a double-blinded, randomized controlled trial whereby 736 mothers were administered n-3 LCPUFA or control from pregnancy week 24 until 1 week after birth. We measured the number of days with gastroenteritis, number of episodes with gastroenteritis, and the risk of having a gastroenteritis episode in the first 3 years of life.

RESULTS

A median reduction of 2.5 days with gastroenteritis (P = .018) was shown, corresponding to a 14% reduction in the n-3 LCPUFA group compared with controls in the first 3 years of life (P = .037). A reduction in the number of gastroenteritis episodes (P = .027) and a reduced risk of having an episode (hazard ratio, 0.80 [95% confidence interval, .66-.97]; P = .023) were also shown.

CONCLUSIONS

Fish oil supplementation from the 24th week of pregnancy led to a reduction in the number of days and episodes with gastroenteritis symptoms in the first 3 years of life. The findings suggest n-3 LCPUFA supplementation as a preventive measure against gastrointestinal infections in early childhood.

CLINICAL TRIALS REGISTRATION

NCT00798226.

Novel blood-based biomarker candidates in screening for colorectal cancer

244

Background: Colorectal cancer (CRC) is the third most common cancer worldwide motivating national screening strategies utilizing fecal immunochemical tests (FIT). Blood-based biomarkers could be an alternative method to increase compliance in population-based screening programs for early detection of CRC. We aimed to identify new blood-based biomarkers that could be potential candidates for use in colorectal cancer screening. Methods: In a nested cohort study of 1967 FIT positive participants of the Danish CRC screening program serum levels of GDF-15, hepsin, IL-8, keratin1-10, L1CAM, MIA, monocyte MCP-1, NSE and OPG were measured using the Luminex xMAP immunoassay platform. Main outcomes were CRC vs non-CRC and CRC, high-risk adenomas (HRA) or medium-risk adenomas (MRA) vs low-risk adenomas (LRA) or clean colorectum. Odds ratios for associations between biomarker expressions and outcomes were calculated using logistic regression models and visualized by area under the receiver operating characteristic (ROC) curve (AUC). Analyses were made on the Luminex biomarkers alone and with addition of clinical and demographic information. Results: FIT-induced colonoscopies detected 240 CRCs and 625 HRA or MRA. Multivariate analyses using all biomarkers and age found hepsin, IL-8 and OPG significantly (p<0.001) associated in relation to the main outcome (CRC vs non-CRC) with odds ratios of 0.74 [0.59-0.92], 2.59 [2.12-3.15] and 0.90 [0.82-0.99], respectively. The full model using all biomarkers and age presented an AUC of 0.73 [0.70-0.77]. Conclusions: Changed serum levels of nine novel biomarkers seem to be potential predictors for early detection of CRC, especially hepsin, IL-8 and OPG. [Table: see text]

Furan fatty acid metabolite in newborns predicts risk of asthma

BACKGROUND

Intake of fish-oil and fatty fish during pregnancy has been shown to reduce the risk of childhood asthma but biomarkers of such intake are lacking.

OBJECTIVE

To establish biomarkers of prenatal fish-oil exposure from newborn dry blood spot metabolomics profiles and assess their relevance for childhood asthma risk stratification.

METHODS

The Danish COPSAC₂₀₁₀ mother-child cohort was utilized to investigate the effect of a double-blinded randomized controlled trial of fish-oil supplementation during pregnancy on dry blood spot liquid-chromatography mass spectrometry-based metabolomics profiles of 677 newborns. We thereafter investigated the association between fish-oil associated biomarkers in the newborn and development of asthma-related outcomes. Replication was sought in the independent observational COPSAC₂₀₀₀ cohort with 387 newborn metabolomics profiles.

RESULTS

The newborn metabolomics profiles differed between children in the fish-oil vs. placebo group in COPSAC₂₀₁₀ (area under the receiver operator curve = 0.94 ± 0.03, p < .001). The fish-oil metabolomics profile and the top biomarker, 3-carboxy-4-methyl-5-propyl-2-furan propanoic acid (CMPF) were both associated with a decreased risk of asthma by age 6 years (HR = 0.89, p = .002 and HR = 0.67, p = .005, respectively). In COPSAC₂₀₀₀ , newborn CMPF level was also inversely associated with asthma risk by age 6 years (HR = 0.69, p = .01). Troublesome lung symptoms and common infections in the first 3 years were also inversely associated with newborn CMPF levels in both cohorts.

CONCLUSIONS

Newborn children's blood levels of the furan fatty acid metabolite CMPF reflect fish-oil and fatty fish intake during pregnancy and are associated with a lower risk of asthma across two cohorts, which could aid newborn screening for childhood asthma.

Nation-wide participation in FIT-based colorectal cancer screening in Denmark during the COVID-19 pandemic: An observational study

Background: Worldwide, most colorectal cancer screening programmes were paused at the start of the COVID-19 pandemic, whilst the Danish faecal immunochemical test (FIT)-based programme continued without pausing. We examined colorectal cancer screening participation and compliance with subsequent colonoscopy in Denmark throughout the pandemic.

Methods: We used data from the Danish Colorectal Cancer Screening Database among individuals aged 50-74 years old invited to participate in colorectal cancer screening from 2018-2021 combined with population-wide registries. Using a generalised linear model, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) of colorectal cancer screening participation within 90 days since invitation and compliance with colonoscopy within 60 days since a positive FIT test during the pandemic in comparison with the previous years adjusting for age, month and year of invitation.

Results: Altogether, 3,133,947 invitations were sent out to 1,928,725 individuals and there were 94,373 positive FIT tests (in 92,848 individuals) during the study period. Before the pandemic, 60.7% participated in screening within 90 days. A minor reduction in participation was observed at the start of the pandemic (PR=0.95; 95% CI: 0.94-0.96 in pre-lockdown and PR=0.85; 95% CI: 0.85-0.86 in 1^st lockdown) corresponding to a participation rate of 54.9% during pre-lockdown and 53.0% during 1st lockdown. This was followed by a 5-10% increased participation in screening corresponding to a participation rate of up to 64.9%. The largest increase in participation was observed among 55-59 year olds and among immigrants. The compliance with colonoscopy within 60 days was 89.9% before the pandemic. A slight reduction was observed during 1^st lockdown (PR=0.96; 95% CI: 0.93-0.98), where after it resumed to normal levels.

Conclusions: Participation in the Danish FIT-based colorectal cancer screening programme and subsequent compliance to colonoscopy after a positive FIT result was only slightly affected by the COVID-19 pandemic.

Funding: The study was funded by the Danish Cancer Society Scientific Committee (grant number R321-A17417) and the Danish regions.

Faecal haemoglobin concentrations are associated with all-cause mortality and cause of death in colorectal cancer screening

BACKGROUND

Colorectal cancer (CRC) screening reduces all-cause and CRC-related mortality. New research demonstrates that the faecal haemoglobin concentration (f-Hb) may indicate the presence of other serious diseases not related to CRC. We investigated the association between f-Hb, measured by a faecal immunochemical test (FIT), and both all-cause mortality and cause of death in a population-wide cohort of screening participants.

METHODS

Between 2014 and 2018, 1,262,165 participants submitted a FIT for the Danish CRC screening programme. We followed these participants, using the Danish CRC Screening Database and several other national registers on health and population, until December 31, 2018. We stratified participants by f-Hb and compared them using a Cox proportional hazards regression on all-cause mortality and cause of death reported as adjusted hazard ratios (aHRs). We adjusted for several covariates, including comorbidity, socioeconomic factors, demography and prescription medication.

RESULTS

We observed 21,847 deaths in the study period. Our multivariate analyses indicated an association relationship between increasing f-Hb and the risk of dying in the study period. This risk increased steadily from aHR 1.38 (95% CI: 1.32, 1.44) in those with a f-Hb of 7.1-11.9 μg Hb/g faeces to 2.20 (95% CI: 2.10, 2.30) in those with a f-Hb ≥60.0 μg Hb/g faeces, when compared to those with a f-Hb ≤7.0 μg Hb/g faeces. The pattern remained when excluding CRC from the analysis. Similar patterns were observed between incrementally increasing f-Hb and the risk of dying from respiratory disease, cardiovascular disease and cancers other than CRC. Furthermore, we observed an increased risk of dying from CRC with increasing f-Hb.

CONCLUSIONS

Our findings support the hypothesis that f-Hb may indicate an elevated risk of having chronic conditions if causes for the bleeding have not been identified. The mechanisms still need to be established, but f-Hb may be a potential biomarker for several non-CRC diseases.

Improvements in metagenomic virus detection by simple pretreatment methods

Early detection of pathogens at the point of care helps reduce the threats to human and animal health from emerging pathogens. Initially, the disease-causing agent will be unknown and needs to be identified; this often requires specific laboratory facilities. Here we describe the development of an unbiased detection assay for RNA and DNA viruses using metagenomic Nanopore sequencing and simple methods that can be transferred into a field setting. Human clinical samples containing the RNA virus SARS-CoV-2 or the DNA viruses human papillomavirus (HPV) and molluscum contagiosum virus (MCV) were used as a test of concept. Firstly, the virus detection potential was optimized by investigating different pretreatments for reducing non-viral nucleic acid components. DNase I pretreatment followed by filtration increased the proportion of SARS-CoV-2 sequenced reads > 500-fold compared with no pretreatments. This was sufficient to achieve virus detection with high confidence and allowed variant identification. Next, we tested individual SARS-CoV-2 samples with various viral loads (measured as CT-values determined by RT-qPCR). Lastly, we tested the assay on clinical samples containing the DNA virus HPV and co-infection with MCV to show the assay's detection potential for DNA viruses. This protocol is fast (same day results). We hope to apply this method in other settings for point of care detection of virus pathogens, thus eliminating the need for transport of infectious samples, cold storage and a specialized laboratory.

Household transmission of SARS-CoV-2 Omicron variant of concern subvariants BA.1 and BA.2 in Denmark

SARS coronavirus 2 (SARS-CoV-2) continues to evolve and new variants emerge. Using nationwide Danish data, we estimate the transmission dynamics of SARS-CoV-2 Omicron subvariants BA.1 and BA.2 within households. Among 22,678 primary cases, we identified 17,319 secondary infections among 50,588 household contacts during a 1-7 day follow-up. The secondary attack rate (SAR) was 29% and 39% in households infected with Omicron BA.1 and BA.2, respectively. BA.2 was associated with increased susceptibility of infection for unvaccinated household contacts (Odds Ratio (OR) 1.99; 95%-CI 1.72-2.31), fully vaccinated contacts (OR 2.26; 95%-CI 1.95-2.62) and booster-vaccinated contacts (OR 2.65; 95%-CI 2.29-3.08), compared to BA.1. We also found increased infectiousness from unvaccinated primary cases infected with BA.2 compared to BA.1 (OR 2.47; 95%-CI 2.15-2.84), but not for fully vaccinated (OR 0.66; 95%-CI 0.57-0.78) or booster-vaccinated primary cases (OR 0.69; 95%-CI 0.59-0.82). Omicron BA.2 is inherently more transmissible than BA.1. Its immune-evasive properties also reduce the protective effect of vaccination against infection, but do not increase infectiousness of breakthrough infections from vaccinated individuals.

Household transmission of SARS-CoV-2 Omicron variant of concern subvariants BA.1 and BA.2 in Denmark

SARS coronavirus 2 (SARS-CoV-2) continues to evolve and new variants emerge. Using nationwide Danish data, we estimate the transmission dynamics of SARS-CoV-2 Omicron subvariants BA.1 and BA.2 within households. Among 22,678 primary cases, we identified 17,319 secondary infections among 50,588 household contacts during a 1–7 day follow-up. The secondary attack rate (SAR) was 29% and 39% in households infected with Omicron BA.1 and BA.2, respectively. BA.2 was associated with increased susceptibility of infection for unvaccinated household contacts (Odds Ratio (OR) 1.99; 95%–CI 1.72-2.31), fully vaccinated contacts (OR 2.26; 95%–CI 1.95–2.62) and booster-vaccinated contacts (OR 2.65; 95%–CI 2.29–3.08), compared to BA.1. We also found increased infectiousness from unvaccinated primary cases infected with BA.2 compared to BA.1 (OR 2.47; 95%–CI 2.15–2.84), but not for fully vaccinated (OR 0.66; 95%–CI 0.57–0.78) or booster-vaccinated primary cases (OR 0.69; 95%–CI 0.59–0.82). Omicron BA.2 is inherently more transmissible than BA.1. Its immune-evasive properties also reduce the protective effect of vaccination against infection, but do not increase infectiousness of breakthrough infections from vaccinated individuals.

In this study, the authors use household data from Denmark to investigate the transmissibility of the BA.1 and BA.2 Omicron SARS-CoV-2 subvariants. They find that the secondary attack rate was higher for BA.2, but that it had higher infectiousness only when cases were not vaccinated.

Household transmission of SARS-CoV-2 Omicron variant of concern subvariants BA.1 and BA.2 in Denmark

SARS coronavirus 2 (SARS-CoV-2) continues to evolve and new variants emerge. Using nationwide Danish data, we estimate the transmission dynamics of SARS-CoV-2 Omicron subvariants BA.1 and BA.2 within households. Among 22,678 primary cases, we identified 17,319 secondary infections among 50,588 household contacts during a 1-7 day follow-up. The secondary attack rate (SAR) was 29% and 39% in households infected with Omicron BA.1 and BA.2, respectively. BA.2 was associated with increased susceptibility of infection for unvaccinated household contacts (Odds Ratio (OR) 1.99; 95%-CI 1.72-2.31), fully vaccinated contacts (OR 2.26; 95%-CI 1.95-2.62) and booster-vaccinated contacts (OR 2.65; 95%-CI 2.29-3.08), compared to BA.1. We also found increased infectiousness from unvaccinated primary cases infected with BA.2 compared to BA.1 (OR 2.47; 95%-CI 2.15-2.84), but not for fully vaccinated (OR 0.66; 95%-CI 0.57-0.78) or booster-vaccinated primary cases (OR 0.69; 95%-CI 0.59-0.82). Omicron BA.2 is inherently more transmissible than BA.1. Its immune-evasive properties also reduce the protective effect of vaccination against infection, but do not increase infectiousness of breakthrough infections from vaccinated individuals.

Household transmission of the SARS-CoV-2 Omicron variant in Denmark

In late 2021, the Omicron SARS-CoV-2 variant overtook the previously dominant Delta variant, but the extent to which this transition was driven by immune evasion or a change in the inherent transmissibility is currently unclear. We estimate SARS-CoV-2 transmission within Danish households during December 2021. Among 26,675 households (8,568 with the Omicron VOC), we identified 14,140 secondary infections within a 1-7-day follow-up period. The secondary attack rate was 29% and 21% in households infected with Omicron and Delta, respectively. For Omicron, the odds of infection were 1.10 (95%-CI: 1.00-1.21) times higher for unvaccinated, 2.38 (95%-CI: 2.23-2.54) times higher for fully vaccinated and 3.20 (95%-CI: 2.67-3.83) times higher for booster-vaccinated contacts compared to Delta. We conclude that the transition from Delta to Omicron VOC was primarily driven by immune evasiveness and to a lesser extent an inherent increase in the basic transmissibility of the Omicron variant.

Vaccine effectiveness against SARS-CoV-2 infection or COVID-19 hospitalization with the Alpha, Delta, or Omicron SARS-CoV-2 variant: A nationwide Danish cohort study

BACKGROUND

The continued occurrence of more contagious Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants and waning immunity over time require ongoing reevaluation of the vaccine effectiveness (VE). This study aimed to estimate the effectiveness in 2 age groups (12 to 59 and 60 years or above) of 2 or 3 vaccine doses (BNT162b2 mRNA or mRNA-1273) by time since vaccination against SARS-CoV-2 infection and Coronavirus Disease 2019 (COVID-19) hospitalization in an Alpha-, Delta-, or Omicron-dominated period.

METHODS AND FINDINGS

A Danish nationwide cohort study design was used to estimate VE against SARS-CoV-2 infection and COVID-19 hospitalization with the Alpha, Delta, or Omicron variant. Information was obtained from nationwide registries and linked using a unique personal identification number. The study included all previously uninfected residents in Denmark aged 12 years or above (18 years or above for the analysis of 3 doses) in the Alpha (February 20 to June 15, 2021), Delta (July 4 to November 20, 2021), and Omicron (December 21, 2021 to January 31, 2022) dominated periods. VE estimates including 95% confidence intervals (CIs) were calculated (1-hazard ratio∙100) using Cox proportional hazard regression models with underlying calendar time and adjustments for age, sex, comorbidity, and geographical region. Vaccination status was included as a time-varying exposure. In the oldest age group, VE against infection after 2 doses was 90.7% (95% CI: 88.2; 92.7) for the Alpha variant, 82.3% (95% CI: 75.5; 87.2) for the Delta variant, and 39.9% (95% CI: 26.3; 50.9) for the Omicron variant 14 to 30 days since vaccination. The VE waned over time and was 73.2% (Alpha, 95% CI: 57.1; 83.3), 50.0% (Delta, 95% CI: 46.7; 53.0), and 4.4% (Omicron, 95% CI: -0.1; 8.7) >120 days since vaccination. Higher estimates were observed after the third dose with VE estimates against infection of 86.1% (Delta, 95% CI: 83.3; 88.4) and 57.7% (Omicron, 95% CI: 55.9; 59.5) 14 to 30 days since vaccination. Among both age groups, VE against COVID-19 hospitalization 14 to 30 days since vaccination with 2 or 3 doses was 98.1% or above for the Alpha and Delta variants. Among both age groups, VE against COVID-19 hospitalization 14 to 30 days since vaccination with 2 or 3 doses was 95.5% or above for the Omicron variant. The main limitation of this study is the nonrandomized study design including potential differences between the unvaccinated (reference group) and vaccinated individuals.

CONCLUSIONS

Two vaccine doses provided high protection against SARS-CoV-2 infection and COVID-19 hospitalization with the Alpha and Delta variants with protection, notably against infection, waning over time. Two vaccine doses provided only limited and short-lived protection against SARS-CoV-2 infection with Omicron. However, the protection against COVID-19 hospitalization following Omicron SARS-CoV-2 infection was higher. The third vaccine dose substantially increased the level and duration of protection against infection with the Omicron variant and provided a high level of sustained protection against COVID-19 hospitalization among the +60-year-olds.

Success rates of smoking cessation therapies to patients with mental illness by video consultants or by treatment in the community: A Randomized Controlled Trial

Introduction

Smoking is probably the one single factor with the highest impact on reducing the life expectancies of patients with mental illness. In Denmark, 38.8% of patients with persistent mental health problem are smoking. Patients may have problem in participating in ordinary smoking cession programs offered in the community, but they are concerned about the impact of tobacco use on their health and finances and are motivated to stop smoking.Videoconferencing addressing smoking cessation might be an alternative to ordinary consultation at the clinic because the patients can access the treatment at home.

Objectives

Compare rates of smoking cessation in two interventions.

Methods

Patients diagnosed with schizophrenia, bipolar disorders or depression in 3 outpatient clinics are eligible for inclusion.Primary outcome is changes in number of cigarettes smoked pr. patients per day in at 6-month follow-up. Secondary outcome is abstinence from smoking at 6-month follow-up.This is a two-arm randomized controlled trial. 1. Daily video consultants at the start of smoking cessation and the months after. 2. Treatment as usual consistent of smoking cessation treatment in the community by weekly consultants.

Results

By September 2021, we have included 64 patients. Among patients, receiving video 26% has stopped and 15% has stopped from treatment as usual.Many patients has reduced their smoking considerably. The patients in general express that they are satisfied with both interventions.

Conclusions

Smoking cessation delivered by daily short video consultants seems to be the best and most effective way to help patients with serious mental illness to stop smoking.

Disclosure

No significant relationships.

Cold water swimming as an add-on treatment for depression. A feasibility study

Introduction

In Denmark, about 14% of patients with depression develops treatment resistant depression (TRD) in the following year after the first hospital contact. Possible explanations for TRD include lack of adequate clinical effect of pharmacological treatment and reluctance to treatment due to unacceptable side effects. Cold water swimming (CWS), also known as winter swimming, describes swimming outdoors - mainly during the winter season in cold to ice-cold water on a regular basis. Many winter swimmers believe that exposure to cold water is beneficial for their health. However, evidence of health effects have been anecdotal or based on results from small sample-size studies. The availably studies report that winter swimming abolishes general tiredness, boosts self-esteem and improves mood and/or general well-being.

Objectives

To test if it is possible for patients with depression to participate in two weekly sessions of CWS and to measure the effects of CWS on general well-being and depression among the participating patients.

Methods

All psychiatric in- and outpatients from the department of psychiatry at Little Belt Hospital, Vejle with a diagnose of depression are eligible for inclusion. CWS-sessions will include a dip in an inlet - and if desired a short swim for a few minutes – depending on individual preferences. The CWS sessions will take place at the local inlet at a recreational area with sauna and changing facilities available.

Results

The study starts in October 2021 and we expect to have results by April 2022.

Conclusions

Conclusion: Awaiting.

Disclosure

No significant relationships.

POS0076 DRUG SURVIVAL OF BIOLOGICS AND NOVEL IMMUNOMODULATORS FOR RHEUMATOID ARTHRITIS, AXIAL SPONDYLOARTHRITIS, PSORIATIC ARTHRITIS, AND PSORIASIS - A NATIONWIDE COHORT STUDY FROM THE DANBIO AND DERMBIO REGISTRIES

Background

Drug survival is an important proxy measure for effectiveness of treatments for inflammatory diseases such as rheumatoid arthritis (RA), axial spondyloarthritis (AxSpA), psoriatic arthritis (PsA), and psoriasis [1-4].

Objectives

The objective of this study was to examine the real-life drug survival of biologics and novel small-molecule therapies across various disease entities such as RA, AxSpA, PsA, and psoriasis.

Methods

We performed a nationwide cohort study using the prospective nationwide registries DANBIO and DERMBIO, comprising all patients treated with biologics or novel small-molecule therapies for RA, AxSpA, PsA, and psoriasis between January 2015 through May 2021 (DANBIO) and November 2009 to November 2019 (DERMBIO). Drug survival was visualized using Kaplan-Meier curves, and Cox proportional hazards models were used to calculate adjusted Hazard Ratios (HRs) with 95% confidence intervals (CIs) for risk of discontinuing therapy.

Results

The study comprised a total of 12,089 patients (17,903 treatment series), including 5,104 RA patients (7,867 series), 2,157 AxSpA patients (3,016 series3), 2,551 PsA patients (3,313 series), and 2,577 psoriasis patients (3,707 series). In confounder-adjusted models drug survival in RA was highest for rituximab followed by baricitinib, etanercept and tocilizumab respectively. For AxSpA drug survival was high for golimumab compared to all other drugs, followed by secukinumab and etanercept and lowest for infliximab. For PsA tofacitinib and infliximab had the lowest drug survival compared to all other drugs. All other drugs performed almost equally well with a tendency of a generally higher drug survival for golimumab, followed by secukinumab and ixekizumab. For psoriasis drug survival was generally highest for guselkumab.

Figure 1.

Conclusion

Differing treatment responses to drugs with various types of action across RA, AxSpA, PsA and psoriasis emphasize that although these diseases have many overlaps in their pathogenesis, there is a need for an individualized treatment approach that considers the underlying disease, patient profile, and treatment history.

References

[1]Egeberg A, Ottosen MB, Gniadecki R, et al. Safety, efficacy and drug survival of biologics and biosimilars for moderate-to-severe plaque psoriasis. Br J Dermatol 2018; 178(2): 509-19.

[2]Gron KL, Glintborg B, Norgaard M, et al. Comparative Effectiveness of Certolizumab Pegol, Abatacept, and Biosimilar Infliximab in Patients With Rheumatoid Arthritis Treated in Routine Care: Observational Data From the Danish DANBIO Registry Emulating a Randomized Trial. Arthritis Rheumatol 2019; 71(12): 1997-2004.

[3]Lindstrom U, Glintborg B, Di Giuseppe D, et al. Comparison of treatment retention and response to secukinumab versus tumour necrosis factor inhibitors in psoriatic arthritis. Rheumatology 2020.

[4]Glintborg B, Lindstrom U, Di Giuseppe D, et al. One-year treatment outcomes of secukinumab versus tumor necrosis factor inhibitors in Spondyloarthritis. Arthritis Care Res (Hoboken) 2020.

Acknowledgements

We acknowledge the substantial contribution of the academic hospitals and private clinics and their physicians that report data to DANBIO and DERMBIO.

Disclosure of Interests

Alexander Egeberg Speakers bureau: AbbVie, Almirall, Leo Pharma, Zuellig Pharma Ltd., Galápagos NV, Sun Pharmaceuticals, Samsung Bioepis Co., Ltd., Pfizer, Eli Lilly and Company, Novartis, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and Janssen Pharmaceuticals, Paid instructor for: AbbVie, Almirall, Leo Pharma, Zuellig Pharma Ltd., Galápagos NV, Sun Pharmaceuticals, Samsung Bioepis Co., Ltd., Pfizer, Eli Lilly and Company, Novartis, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and Janssen Pharmaceuticals, Consultant of: AbbVie, Almirall, Leo Pharma, Zuellig Pharma Ltd., Galápagos NV, Sun Pharmaceuticals, Samsung Bioepis Co., Ltd., Pfizer, Eli Lilly and Company, Novartis, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and Janssen Pharmaceuticals, Grant/research support from: Pfizer, Eli Lilly, Novartis, Bristol-Myers Squibb, AbbVie, Janssen Pharmaceuticals, Nana Lippert Rosenoe: None declared, David Aagaard: None declared, Erik Lørup: None declared, Lea Nymand: None declared, Lars Erik Kristensen Speakers bureau: Dr. LE Kristensen has received fees for speaking and consultancy from Pfizer, AbbVie, Amgen, Forward pharma, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly, and Janssen pharmaceuticals, Paid instructor for: Dr. LE Kristensen has received fees for speaking and consultancy from Pfizer, AbbVie, Amgen, Forward pharma, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly, and Janssen pharmaceuticals, Consultant of: Dr. LE Kristensen has received fees for speaking and consultancy from Pfizer, AbbVie, Amgen, Forward pharma, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly, and Janssen pharmaceuticals, Grant/research support from: Dr. LE Kristensen has received fees for speaking and consultancy from Pfizer, AbbVie, Amgen, Forward pharma, UCB, Gilead, Biogen, BMS, MSD, Novartis, Eli Lilly, and Janssen pharmaceuticals, Jacob Thyssen Speakers bureau: Dr. Thyssen has attended advisory boards for Almirall, Eli Lilly & Co, Pfizer, LEO Pharma, Asana, Regeneron, AbbVie, Union Therapeutics, and Sanofi-Genzyme and received speaker honorarium from LEO Pharma, Regeneron, Almirall, Abbvie, Eli Lilly & Co, and Sanofi-Genzyme, and been an investigator for AbbVie, Pfizer, Eli Lilly & Co, LEO Pharma and Sanofi-Genzyme., Paid instructor for: Dr. Thyssen has attended advisory boards for Almirall, Eli Lilly & Co, Pfizer, LEO Pharma, Asana, Regeneron, AbbVie, Union Therapeutics, and Sanofi-Genzyme and received speaker honorarium from LEO Pharma, Regeneron, Almirall, Abbvie, Eli Lilly & Co, and Sanofi-Genzyme, and been an investigator for AbbVie, Pfizer, Eli Lilly & Co, LEO Pharma and Sanofi-Genzyme., Consultant of: Dr. Thyssen has attended advisory boards for Almirall, Eli Lilly & Co, Pfizer, LEO Pharma, Asana, Regeneron, AbbVie, Union Therapeutics, and Sanofi-Genzyme and received speaker honorarium from LEO Pharma, Regeneron, Almirall, Abbvie, Eli Lilly & Co, and Sanofi-Genzyme, and been an investigator for AbbVie, Pfizer, Eli Lilly & Co, LEO Pharma and Sanofi-Genzyme., Grant/research support from: Dr. Thyssen has attended advisory boards for Almirall, Eli Lilly & Co, Pfizer, LEO Pharma, Asana, Regeneron, AbbVie, Union Therapeutics, and Sanofi-Genzyme and received speaker honorarium from LEO Pharma, Regeneron, Almirall, Abbvie, Eli Lilly & Co, and Sanofi-Genzyme, and been an investigator for AbbVie, Pfizer, Eli Lilly & Co, LEO Pharma and Sanofi-Genzyme., Simon F. Thomsen Speakers bureau: Dr. Thomsen has been a speaker or has served on advisory boards for Sanofi-Genzyme, AbbVie, LEO Pharma, Pfizer, Eli Lilly and Company, Novartis, UCB Pharma, Almirall, and Janssen Pharmaceuticals; has received research support from Sanofi-Genzyme, AbbVie, LEO Pharma, Novartis, UCB Pharma, and Janssen Pharmaceuticals; and has been an investigator for Sanofi-Genzyme, Regeneron, AbbVie, LEO Pharma, Novartis and Pfizer., Paid instructor for: Dr. Thomsen has been a speaker or has served on advisory boards for Sanofi-Genzyme, AbbVie, LEO Pharma, Pfizer, Eli Lilly and Company, Novartis, UCB Pharma, Almirall, and Janssen Pharmaceuticals; has received research support from Sanofi-Genzyme, AbbVie, LEO Pharma, Novartis, UCB Pharma, and Janssen Pharmaceuticals; and has been an investigator for Sanofi-Genzyme, Regeneron, AbbVie, LEO Pharma, Novartis and Pfizer., Consultant of: Dr. Thomsen has been a speaker or has served on advisory boards for Sanofi-Genzyme, AbbVie, LEO Pharma, Pfizer, Eli Lilly and Company, Novartis, UCB Pharma, Almirall, and Janssen Pharmaceuticals; has received research support from Sanofi-Genzyme, AbbVie, LEO Pharma, Novartis, UCB Pharma, and Janssen Pharmaceuticals; and has been an investigator for Sanofi-Genzyme, Regeneron, AbbVie, LEO Pharma, Novartis and Pfizer., Grant/research support from: Dr. Thomsen has been a speaker or has served on advisory boards for Sanofi-Genzyme, AbbVie, LEO Pharma, Pfizer, Eli Lilly and Company, Novartis, UCB Pharma, Almirall, and Janssen Pharmaceuticals; has received research support from Sanofi-Genzyme, AbbVie, LEO Pharma, Novartis, UCB Pharma, and Janssen Pharmaceuticals; and has been an investigator for Sanofi-Genzyme, Regeneron, AbbVie, LEO Pharma, Novartis and Pfizer., René Lindholm Cordtz: None declared, Nikolai Loft Speakers bureau: speaker for Eli Lilly and Janssen Cilag., Lone Skov Speakers bureau: Dr. Skov has been a paid speaker for AbbVie, Eli Lilly, Novartis, and LEO Pharma, and has been a consultant or has served on Advisory Boards with AbbVie, Janssen Cilag, Novartis, Eli Lilly, LEO Pharma, UCB, Almirall, and Sanofi. She has served as an investigator for AbbVie, Sanofi, Janssen Cilag, Boehringer Ingelheim, AstraZenica, Eli Lilly, Novartis, Regeneron, and LEO Pharma, and has received research and educational grants from Novartis, Sanofi, Janssen Cilag, and LEO Pharma., Paid instructor for: Dr. Skov has been a paid speaker for AbbVie, Eli Lilly, Novartis, and LEO Pharma, and has been a consultant or has served on Advisory Boards with AbbVie, Janssen Cilag, Novartis, Eli Lilly, LEO Pharma, UCB, Almirall, and Sanofi. She has served as an investigator for AbbVie, Sanofi, Janssen Cilag, Boehringer Ingelheim, AstraZenica, Eli Lilly, Novartis, Regeneron, and LEO Pharma, and has received research and educational grants from Novartis, Sanofi, Janssen Cilag, and LEO Pharma., Consultant of: Dr. Skov has been a paid speaker for AbbVie, Eli Lilly, Novartis, and LEO Pharma, and has been a consultant or has served on Advisory Boards with AbbVie, Janssen Cilag, Novartis, Eli Lilly, LEO Pharma, UCB, Almirall, and Sanofi. She has served as an investigator for AbbVie, Sanofi, Janssen Cilag, Boehringer Ingelheim, AstraZenica, Eli Lilly, Novartis, Regeneron, and LEO Pharma, and has received research and educational grants from Novartis, Sanofi, Janssen Cilag, and LEO Pharma., Grant/research support from: Dr. Skov has been a paid speaker for AbbVie, Eli Lilly, Novartis, and LEO Pharma, and has been a consultant or has served on Advisory Boards with AbbVie, Janssen Cilag, Novartis, Eli Lilly, LEO Pharma, UCB, Almirall, and Sanofi. She has served as an investigator for AbbVie, Sanofi, Janssen Cilag, Boehringer Ingelheim, AstraZenica, Eli Lilly, Novartis, Regeneron, and LEO Pharma, and has received research and educational grants from Novartis, Sanofi, Janssen Cilag, and LEO Pharma., Lars Erik Bryld: None declared, Mads Rasmussen Speakers bureau: Dr. Rasmussen has been a paid speaker for AbbVie, Almirall, and LEO Pharma. Consulting, or serving on expert/advisory boards with AbbVie, Almirall, Janssen Cilag, and Eli Lilly. He served as investigator for Janssen Cilag, UCB, and Novartis., Paid instructor for: Dr. Rasmussen has been a paid speaker for AbbVie, Almirall, and LEO Pharma. Consulting, or serving on expert/advisory boards with AbbVie, Almirall, Janssen Cilag, and Eli Lilly. He served as investigator for Janssen Cilag, UCB, and Novartis., Consultant of: Dr. Rasmussen has been a paid speaker for AbbVie, Almirall, and LEO Pharma. Consulting, or serving on expert/advisory boards with AbbVie, Almirall, Janssen Cilag, and Eli Lilly. He served as investigator for Janssen Cilag, UCB, and Novartis., Grant/research support from: Dr. Rasmussen has been a paid speaker for AbbVie, Almirall, and LEO Pharma. Consulting, or serving on expert/advisory boards with AbbVie, Almirall, Janssen Cilag, and Eli Lilly. He served as investigator for Janssen Cilag, UCB, and Novartis., Pil Højgaard: None declared, Salome Kristensen: None declared, Lene Dreyer Speakers bureau: Dr. Dreyer has received research grant/research support from BMS, and speakers bureau from Eli Lilly and Galderma., Paid instructor for: Dr. Dreyer has received research grant/research support from BMS, and speakers bureau from Eli Lilly and Galderma., Consultant of: Dr. Dreyer has received research grant/research support from BMS, and speakers bureau from Eli Lilly and Galderma., Grant/research support from: Dr. Dreyer has received research grant/research support from BMS, and speakers bureau from Eli Lilly and Galderma.

Introduction and transmission of SARS-CoV-2 lineage B.1.1.7, Alpha variant, in Denmark

Background

In early 2021, the SARS-CoV-2 lineage B.1.1.7 (Alpha variant) became dominant across large parts of the world. In Denmark, comprehensive and real-time test, contact-tracing, and sequencing efforts were applied to sustain epidemic control. Here, we use these data to investigate the transmissibility, introduction, and onward transmission of B.1.1.7 in Denmark.

Methods

We analyzed a comprehensive set of 60,178 SARS-CoV-2 genomes generated from high-throughput sequencing by the Danish COVID-19 Genome Consortium, representing 34% of all positive cases in the period 14 November 2020 to 7 February 2021. We calculated the transmissibility of B.1.1.7 relative to other lineages using Poisson regression. Including all 1976 high-quality B.1.1.7 genomes collected in the study period, we constructed a time-scaled phylogeny, which was coupled with detailed travel history and register data to outline the introduction and onward transmission of B.1.1.7 in Denmark.

Results

In a period with unchanged restrictions, we estimated an increased B.1.1.7 transmissibility of 58% (95% CI: [56%, 60%]) relative to other lineages. Epidemiological and phylogenetic analyses revealed that 37% of B.1.1.7 cases were related to the initial introduction in November 2020. The relative number of cases directly linked to introductions varied between 10 and 50% throughout the study period.

Conclusions

Our findings corroborate early estimates of increased transmissibility of B.1.1.7. Both substantial early expansion when B.1.1.7 was still unmonitored and continuous foreign introductions contributed considerably to case numbers. Finally, our study highlights the benefit of balanced travel restrictions and self-isolation procedures coupled with comprehensive surveillance efforts, to sustain epidemic control in the face of emerging variants.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13073-022-01045-7.

Method for quantification of porcine type I interferon activity using luminescence, by direct and indirect means

BACKGROUND

Type I interferons are widely used in research applications and as biotherapeutics. Current assays used to measure interferon concentrations, such as plaque reduction assays and ELISA, are expensive, technically challenging, and may take days to provide results. We sought to develop a robust and rapid assay to determine interferon concentrations produced from transiently transfected cell cultures.

METHOD

Indirect quantification of recombinant interferon was evaluated using a novel bi-cistronic construct encoding the Foot-and-mouth disease virus 2A translational interrupter sequence to yield equimolar expression of Gaussia princeps luciferase and porcine interferon α. Direct quantification was evaluated by expression of a novel fusion protein comprised of Gaussia princeps luciferase and porcine type I interferon. Plasmids encoding constructs are transiently transfected into cell cultures and supernatant harvested for testing of luminescence, ELISA determined concentration, and anti-viral activity against vesicular stomatitis virus.

RESULTS

Bi-cistronic constructs, utilized for indirect quantification, demonstrate both luciferase activity and anti-viral activity. Fusion proteins, utilized for direct quantification, retained secretion and luminescence however only the interferon α fusion protein had antiviral activity comparable to wildtype porcine interferon α. A strong linear correlation was observed between dilution and luminescence for all compounds over a dynamic range of concentrations.

CONCLUSION

The correlation of antiviral and luciferase activities demonstrated the utility of this approach, both direct and indirect, to rapidly determine recombinant interferon concentrations. Concentration can be determined over a more dynamic concentration range than available ELISA based assays using this methodology.

Molecular epidemiology of the SARS-CoV-2 variant Omicron BA.2 sub-lineage in Denmark, 29 November 2021 to 2 January 2022

Following emergence of the SARS-CoV-2 variant Omicron in November 2021, the dominant BA.1 sub-lineage was replaced by the BA.2 sub-lineage in Denmark. We analysed the first 2,623 BA.2 cases from 29 November 2021 to 2 January 2022. No epidemiological or clinical differences were found between individuals infected with BA.1 versus BA.2. Phylogenetic analyses showed a geographic east-to-west transmission of BA.2 from the Capital Region with clusters expanding after the Christmas holidays. Mutational analysis shows distinct differences between BA.1 and BA.2.

Varying fecal immunochemical test screening cutoffs by age and gender: a way to increase detection rates and reduce the number of colonoscopies

BACKGROUND AND AIMS

Most colorectal cancer (CRC) screening programs based on the fecal immunochemical test (FIT) use the same cutoff value for all participants. This study aimed at finding age- and gender-specific cutoff values that can improve population-based CRC screening.

METHODS

This observational study used data from the first 2 years of the Danish FIT-based CRC screening program to estimate sensitivity, specificity, number of positive tests, number of screen-detected cancers and adenomas, and number of interval cancers for various cutoff values for different male and female age groups.

RESULTS

Data from 531,828 participants showed that lower cutoff values for older residents and higher cutoff values for younger residents increased the overall sensitivity and specificity, decreased the number of needed colonoscopies by 7%, increased the number of screen-detected cancer by 1.1%, increased the number of screen-detected adenomas by 5%, and decreased the number of interval cancers by approximately 1.5%. However, these cutoff values also increased an inequality in sensitivity and specificity. Choosing cutoff values that ensured equal sensitivity between the groups, however, did increase inequality in, for example, the interval cancer rate.

CONCLUSIONS

In a FIT-based CRC program it is possible to decrease the number of needed colonoscopies while at the same time to increase overall sensitivity and specificity and detect more cancers and adenomas by using different cutoff values for different male and female age groups. However, this increases inequality in sensitivity and specificity, whereas other strategies like ensuring equal sensitivity could be considered.

Cause of Death, Mortality and Occult Blood in Colorectal Cancer Screening

Fecal hemoglobin (f-Hb) detected by the guaiac fecal occult blood test (gFOBT) may be associated with mortality and cause of death in colorectal cancer (CRC) screening participants. We investigated this association in a randomly selected population of 20,694 participants followed for 33 years. We followed participants from the start of the Hemoccult-II CRC trial in 1985-1986 until December 2018. Data on mortality, cause of death and covariates were retrieved using Danish national registers. We conducted multivariable Cox regressions with time-varying exposure, reporting results as crude and adjusted hazard ratios (aHRs). We identified 1766 patients with at least one positive gFOBT, 946 of whom died in the study period. Most gFOBT-positive participants (93.23%) died of diseases unrelated to CRC and showed higher non-CRC mortality than gFOBT-negative participants (aHR: 1.20, 95% CI 1.10-1.30). Positive gFOBT participants displayed a modest increase in all-cause (aHR: 1.28, 95% CI: 1.18-1.38), CRC (aHR: 4.07, 95% CI: 3.00-5.56), cardiovascular (aHR: 1.22, 95% CI: 1.07-1.39) and endocrine and hematological mortality (aHR: 1.58, 95% CI: 1.19-2.10). In conclusion, we observed an association between positive gFOBT, cause of death and mortality. The presence of f-Hb in the gFOBT might indicate the presence of systemic diseases.

RNA profiles reveal signatures of future health and disease in pregnancy

Maternal morbidity and mortality continue to rise, and pre-eclampsia is a major driver of this burden1. Yet the ability to assess underlying pathophysiology before clinical presentation to enable identification of pregnancies at risk remains elusive. Here we demonstrate the ability of plasma cell-free RNA (cfRNA) to reveal patterns of normal pregnancy progression and determine the risk of developing pre-eclampsia months before clinical presentation. Our results centre on comprehensive transcriptome data from eight independent prospectively collected cohorts comprising 1,840 racially diverse pregnancies and retrospective analysis of 2,539 banked plasma samples. The pre-eclampsia data include 524 samples (72 cases and 452 non-cases) from two diverse independent cohorts collected 14.5 weeks (s.d., 4.5 weeks) before delivery. We show that cfRNA signatures from a single blood draw can track pregnancy progression at the placental, maternal and fetal levels and can robustly predict pre-eclampsia, with a sensitivity of 75% and a positive predictive value of 32.3% (s.d., 3%), which is superior to the state-of-the-art method2. cfRNA signatures of normal pregnancy progression and pre-eclampsia are independent of clinical factors, such as maternal age, body mass index and race, which cumulatively account for less than 1% of model variance. Further, the cfRNA signature for pre-eclampsia contains gene features linked to biological processes implicated in the underlying pathophysiology of pre-eclampsia.

Epidemiological characterisation of the first 785 SARS-CoV-2 Omicron variant cases in Denmark, December 2021

By 9 December 2021, 785 SARS-CoV-2 Omicron variant cases have been identified in Denmark. Most cases were fully (76%) or booster-vaccinated (7.1%); 34 (4.3%) had a previous SARS-CoV-2 infection. The majority of cases with available information reported symptoms (509/666; 76%) and most were infected in Denmark (588/644; 91%). One in five cases cannot be linked to previous cases, indicating widespread community transmission. Nine cases have been hospitalised, one required intensive care and no deaths have been registered.

Increased transmissibility of SARS-CoV-2 lineage B.1.1.7 by age and viral load

New lineages of SARS-CoV-2 are of potential concern due to higher transmissibility, risk of severe outcomes, and/or escape from neutralizing antibodies. Lineage B.1.1.7 (the Alpha variant) became dominant in early 2021, but the association between transmissibility and risk factors, such as age of primary case and viral load remains poorly understood. Here, we used comprehensive administrative data from Denmark, comprising the full population (January 11 to February 7, 2021), to estimate household transmissibility. This study included 5,241 households with primary cases; 808 were infected with lineage B.1.1.7 and 4,433 with other lineages. Here, we report an attack rate of 38% in households with a primary case infected with B.1.1.7 and 27% in households with other lineages. Primary cases infected with B.1.1.7 had an increased transmissibility of 1.5-1.7 times that of primary cases infected with other lineages. The increased transmissibility of B.1.1.7 was multiplicative across age and viral load.

Neutralisation of the SARS-CoV-2 Delta variant sub-lineages AY.4.2 and B.1.617.2 with the mutation E484K by Comirnaty (BNT162b2 mRNA) vaccine-elicited sera, Denmark, 1 to 26 November 2021

Several factors may account for the recent increased spread of the SARS-CoV-2 Delta sub-lineage AY.4.2 in the United Kingdom, Romania, Poland, and Denmark. We evaluated the sensitivity of AY.4.2 to neutralisation by sera from 30 Comirnaty (BNT162b2 mRNA) vaccine recipients in Denmark in November 2021. AY.4.2 neutralisation was comparable to other circulating Delta lineages or sub-lineages. Conversely, the less prevalent B.1.617.2 with E484K showed a significant more than 4-fold reduction in neutralisation that warrants surveillance of strains with the acquired E484K mutation.

Neonatal metabolome of cesarean section and risk of childhood asthma

BACKGROUND

Birth by cesarean section (CS) is linked to an increased risk of developing asthma, but the underlying mechanisms are unclear.

OBJECTIVE

To elucidate the link between birth by CS and asthma using newborn metabolomic profiles and integrating early life gut microbiome data and cord blood immunology.

METHODS

We investigated the influence of CS on liquid chromatography mass spectrometry (LC-MS) metabolomic profiles of dried blood spots from newborns of the two independent Copenhagen Prospective Studies on Asthma in Childhood cohorts, i.e. COPSAC2010 (n=677) and COPSAC2000 (n=387). We assessed the associations between the CS metabolic profile, age one-week gut microbiome data and frequency of cord blood Tregs.

RESULTS

In COPSAC2010, a partial least square-discriminant analysis (PLS-DA) model showed that children born by CS versus natural delivery had different metabolic profiles (AUC=0.77, p=2.2e-16), which was replicated in COPSAC2000 (AUC=0.66, p=1.2e-5). The metabolic profile of CS was significantly associated with an increased risk of asthma at school-age in both COPSAC2010 (p=0.03) and COPSAC2000 (p=0.005). CS was associated with lower abundance of tryptophan, bile acid and phenylalanine metabolites, indicative of a perturbed gut microbiota. Further, gut bacteria dominating after natural delivery, i.e. Bifidobacterium and Bacteroides were correlated with CS-discriminative microbial metabolites, suggesting maternal microbial transmission during birth regulating the newborn's metabolism. Finally, the CS metabolic profile was associated with frequency of cord blood Tregs.

CONCLUSIONS

These findings propose that CS is programming the risk of childhood asthma through perturbed immune responses and gut microbial colonization patterns reflected in the blood metabolome at birth.

Infection, recovery and re-infection of farmed mink with SARS-CoV-2

Mink, on a farm with about 15,000 animals, became infected with SARS-CoV-2. Over 75% of tested animals were positive for SARS-CoV-2 RNA in throat swabs and 100% of tested animals were seropositive. The virus responsible had a deletion of nucleotides encoding residues H69 and V70 within the spike protein gene as well as the A22920T mutation, resulting in the Y453F substitution within this protein, seen previously in mink. The infected mink recovered and after free-testing of 300 mink (a level giving 93% confidence of detecting a 1% prevalence), the animals remained seropositive. During further follow-up studies, after a period of more than 2 months without any virus detection, over 75% of tested animals again scored positive for SARS-CoV-2 RNA. Whole genome sequencing showed that the viruses circulating during this re-infection were most closely related to those identified in the first outbreak on this farm but additional sequence changes had occurred. Animals had much higher levels of anti-SARS-CoV-2 antibodies in serum samples after the second round of infection than at free-testing or during recovery from initial infection, consistent with a boosted immune response. Thus, it was concluded that following recovery from an initial infection, seropositive mink were readily re-infected by SARS-CoV-2.

Risk of hospitalisation associated with infection with SARS-CoV-2 lineage B.1.1.7 in Denmark: an observational cohort study

BACKGROUND

The more infectious SARS-CoV-2 lineage B.1.1.7 rapidly spread in Europe after December, 2020, and a concern that B.1.1.7 could cause more severe disease has been raised. Taking advantage of Denmark's high RT-PCR testing and whole genome sequencing capacities, we used national health register data to assess the risk of COVID-19 hospitalisation in individuals infected with B.1.1.7 compared with those with other SARS-CoV-2 lineages.

METHODS

We did an observational cohort study of all SARS-CoV-2-positive cases confirmed by RT-PCR in Denmark, sampled between Jan 1 and March 24, 2021, with 14 days of follow-up for COVID-19 hospitalisation. Cases were identified in the national COVID-19 surveillance system database, which includes data from the Danish Microbiology Database (RT-PCR test results), the Danish COVID-19 Genome Consortium, the National Patient Registry, the Civil Registration System, as well as other nationwide registers. Among all cases, COVID-19 hospitalisation was defined as first admission lasting longer than 12 h within 14 days of a sample with a positive RT-PCR result. The study population and main analysis were restricted to the proportion of cases with viral genome data. We calculated the risk ratio (RR) of admission according to infection with B.1.1.7 versus other co-existing lineages with a Poisson regression model with robust SEs, adjusted a priori for sex, age, calendar time, region, and comorbidities. The contribution of each covariate to confounding of the crude RR was evaluated afterwards by a stepwise forward inclusion.

FINDINGS

Between Jan 1 and March 24, 2021, 50 958 individuals with a positive SARS-CoV-2 test and at least 14 days of follow-up for hospitalisation were identified; 30 572 (60·0%) had genome data, of whom 10 544 (34·5%) were infected with B.1.1.7. 1944 (6·4%) individuals had a COVID-19 hospitalisation and of these, 571 (29·4%) had a B.1.1.7 infection and 1373 (70·6%) had an infection with other SARS-CoV-2 lineages. Although the overall number of hospitalisations decreased during the study period, the proportion of individuals infected with B.1.1.7 increased from 3·5% to 92·1% per week. B.1.1.7 was associated with a crude RR of hospital admission of 0·79 (95% CI 0·72-0·87; p<0·0001) and an adjusted RR of 1·42 (95% CI 1·25-1·60; p<0·0001). The adjusted RR was increased in all strata of age and calendar period-the two covariates with the largest contribution to confounding of the crude RR.

INTERPRETATION

Infection with SARS-CoV-2 lineage B.1.1.7 was associated with an increased risk of hospitalisation compared with that of other lineages in an analysis adjusted for covariates. The overall effect on hospitalisations in Denmark was lessened due to a strict lockdown, but our findings could support hospital preparedness and modelling of the projected impact of the epidemic in countries with uncontrolled spread of B.1.1.7.

FUNDING

None.

In vitro Characterization of Fitness and Convalescent Antibody Neutralization of SARS-CoV-2 Cluster 5 Variant Emerging in Mink at Danish Farms

In addition to humans, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can transmit to animals that include hamsters, cats, dogs, mink, ferrets, tigers, lions, cynomolgus macaques, rhesus macaques, and treeshrew. Among these, mink are particularly susceptible. Indeed, 10 countries in Europe and North America reported SARS-CoV-2 infection among mink on fur farms. In Denmark, SARS-CoV-2 spread rapidly among mink farms and spilled-over back into humans, acquiring mutations/deletions with unknown consequences for virulence and antigenicity. Here we describe a mink-associated SARS-CoV-2 variant (Cluster 5) characterized by 11 amino acid substitutions and four amino acid deletions relative to Wuhan-Hu-1. Temporal virus titration, together with genomic and subgenomic viral RNA quantitation, demonstrated a modest in vitro fitness attenuation of the Cluster 5 virus in the Vero-E6 cell line. Potential alterations in antigenicity conferred by amino acid changes in the spike protein that include three substitutions (Y453F, I692V, and M1229I) and a loss of two amino acid residues 69 and 70 (ΔH69/V70), were evaluated in a virus microneutralization assay. Compared to a reference strain, the Cluster 5 variant showed reduced neutralization in a proportion of convalescent human COVID-19 samples. The findings underscore the need for active surveillance SARS-CoV-2 infection and virus evolution in susceptible animal hosts.