Higher SARS-CoV-2 detection of oropharyngeal compared with nasopharyngeal or saliva specimen for molecular testing: a multicentre randomised comparative accuracy study.

BACKGROUND: Testing is critical for detecting SARS-CoV-2 infection, but the best sampling method remains unclear. OBJECTIVES: To determine whether nasopharyngeal swab (NPS), oropharyngeal swab (OPS) or saliva specimen collection has the highest detection rate for SARS-CoV-2 molecular testing. METHODS: We conducted a randomised clinical trial at two COVID-19 outpatient test centres where NPS, OPS and saliva specimens were collected by healthcare workers in different orders for reverse transcriptase PCR testing. The SARS-CoV-2 detection rate was calculated as the number positive by a specific sampling method divided by the number in which any of the three sampling methods was positive. As secondary outcomes, test-related discomfort was measured with an 11-point numeric scale and cost-effectiveness was calculated. RESULTS: Among 23 102 adults completing the trial, 381 (1.65%) were SARS-CoV-2 positive. The SARS-CoV-2 detection rate was higher for OPSs, 78.7% (95% CI 74.3 to 82.7), compared with NPSs, 72.7% (95% CI 67.9 to 77.1) (p=0.049) and compared with saliva sampling, 61.9% (95% CI 56.9 to 66.8) (p<0.001). The discomfort score was highest for NPSs, at 5.76 (SD, 2.52), followed by OPSs, at 3.16 (SD 3.16) and saliva samples, at 1.03 (SD 18.8), p<0.001 between all measurements. Saliva specimens were associated with the lowest cost, and the incremental costs per detected SARS-CoV-2 infection for NPSs and OPSs were US$3258 and US$1832, respectively. CONCLUSIONS: OPSs were associated with higher SARS-CoV-2 detection and lower test-related discomfort than NPSs for SARS-CoV-2 testing. Saliva sampling had the lowest SARS-CoV-2 detection but was the least costly strategy for mass testing. TRIAL REGISTRATION NUMBER: NCT04715607.

Hepatitis delta infection among persons living with HIV in Europe.

BACKGROUND AND AIMS: A high prevalence of hepatitis delta virus (HDV) infection, the most severe form of viral hepatitis, has been reported among persons living with HIV (PLWH) in Europe. We analysed data from a large HIV cohort collaboration to characterize HDV epidemiological trends across Europe, as well as its impact on clinical outcomes. METHODS: All PLWH with a positive hepatitis B surface antigen (HBsAg) in the Swiss HIV Cohort Study and EuroSIDA between 1988 and 2019 were tested for anti-HDV antibodies and, if positive, for HDV RNA. Demographic and clinical characteristics at initiation of antiretroviral therapy were compared between HDV-positive and HDV-negative individuals using descriptive statistics. The associations between HDV infection and overall mortality, liver-related mortality as well as hepatocellular carcinoma (HCC) were assessed using cumulative incidence plots and cause-specific multivariable Cox regression. RESULTS: Of 2793 HBsAg-positive participants, 1556 (56%) had stored serum available and were included. The prevalence of HDV coinfection was 15.2% (237/1556, 95% confidence interval [CI]: 13.5%-17.1%) and 66% (132/200) of HDV-positive individuals had active HDV replication. Among persons who inject drugs (PWID), the prevalence of HDV coinfection was 50.5% (182/360, 95% CI: 45.3%-55.7%), with similar estimates across Europe, compared to 4.7% (52/1109, 95% CI: 3.5%-5.9%) among other participants. During a median follow-up of 10.8 years (interquartile range 5.6-17.8), 82 (34.6%) HDV-positive and 265 (20.1%) HDV-negative individuals died. 41.5% (34/82) of deaths were liver-related in HDV-positive individuals compared to 17.7% (47/265) in HDV-negative individuals. HDV infection was associated with overall mortality (adjusted hazard ratio 1.6; 95% CI 1.2-2.1), liver-related death (2.9, 1.6-5.0) and HCC (6.3, 2.5-16.0). CONCLUSION: We found a very high prevalence of hepatitis delta among PWID across Europe. Among PLWH who do not inject drugs, the prevalence was similar to that reported from populations without HIV. HDV coinfection was associated with liver-related mortality and HCC incidence.

Incidence and Impact of Parvovirus B19 Infection in Seronegative Solid Organ Transplant Recipients.

Routine monitoring of parvovirus B19 (B19V) the first 6 months posttransplantation was performed in 241 seronegative solid organ transplant (SOT) recipients. Incidence rates during the first month and the second to sixth months posttransplantation were 1.2 (95% confidence interval [CI], .33-3.2) and 0.21 (95% CI, .06-.57) per 100 recipients per month, respectively. Of the 6 SOT recipients with positive B19V polymerase chain reaction, 3 (50%) were admitted to hospital and 2 (33%) were treated with intravenous immunoglobulin. Thus, routine monitoring of B19V in seronegative SOT recipients may not be necessary. Targeted screening 1 month posttransplantation and screening upon clinical suspicion could be an alternative strategy.

Measles, Mumps, Rubella, and Varicella Zoster Virus Serology and Infections in Solid Organ Transplant Recipients During the First Year Posttransplantation.

BACKGROUND: Mumps, measles, rubella, and varicella zoster (MMRV) viruses may cause severe infections in seronegative adult solid organ transplant (SOT) recipients, but can be prevented by vaccination. We aimed to determine MMRV serostatus in adult SOT recipients before and 1 year after transplantation as well as evidence of MMRV infections in a large, prospective cohort of SOT recipients. METHODS: This was a prospective study of 1182 adult SOT recipients included in the Management of Posttransplant Infections in Collaborating Hospitals (MATCH) cohort from 2011 to 2017 with a 1-year follow-up. Systematic monitoring of MMRV serology was performed prior to transplantation and 1 year posttransplantation. Polymerase chain reaction (PCR) was used to confirm viral replication in SOT recipients presenting with clinical evidence of infection. RESULTS: Among 1182 adult SOT recipients, 28 (2.4%), 77 (6.5%), 65 (5.5%), and 22 (1.9%) were seronegative for measles, mumps, rubella, and varicella zoster virus (VZV), respectively, and 165 (14%) were seronegative for at least 1 of the MMRV viruses. One year posttransplantation, 29 of 823 (3.5%) of seropositive SOT recipients had seroreverted, and 63 of 111 (57%) of seronegative SOT recipients seroconverted for at least 1 MMRV virus. No evidence of measles, mumps, or rubella infection was found, but 8 (0.7%) SOT recipients developed symptoms and had a positive VZV PCR. CONCLUSIONS: A large proportion of SOT recipients were seronegative for at least 1 of the MMRV viruses. MMRV infections in SOT recipients may disseminate and become fatal, and although only a few cases of VZV infection were detected, results from this study suggest increase attention toward vaccination of patients waiting for SOT.

Comparison of 16 Serological SARS-CoV-2 Immunoassays in 16 Clinical Laboratories.

Serological assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to support clinical diagnosis and epidemiological investigations. Recently, assays for large-scale detection of total antibodies (Ab), immunoglobulin G (IgG), and IgM against SARS-CoV-2 antigens have been developed, but there are limited data on the diagnostic accuracy of these assays. This study was a Danish national collaboration and evaluated 15 commercial and one in-house anti-SARS-CoV-2 assays in 16 laboratories. Sensitivity was evaluated using 150 samples from individuals with asymptomatic, mild, or moderate COVID-19, nonhospitalized or hospitalized, confirmed by nucleic acid amplification tests (NAAT); samples were collected 13 to 73 days either from symptom onset or from positive NAAT (patients without symptoms). Specificity and cross-reactivity were evaluated in samples collected prior to the SARS-CoV-2 epidemic from >586 blood donors and patients with autoimmune diseases, cytomegalovirus or Epstein-Barr virus infections, and acute viral infections. A specificity of ≥99% was achieved by all total-Ab and IgG assays except one, DiaSorin Liaison XL IgG (97.2%). Sensitivities in descending order were Wantai ELISA total Ab (96.7%), CUH-NOVO in-house ELISA total Ab (96.0%), Ortho Vitros total Ab (95.3%), YHLO iFlash IgG (94.0%), Ortho Vitros IgG (93.3%), Siemens Atellica total Ab (93.2%), Roche Elecsys total Ab (92.7%), Abbott Architect IgG (90.0%), Abbott Alinity IgG (median 88.0%), DiaSorin Liaison XL IgG (median 84.6%), Siemens Vista total Ab (81.0%), Euroimmun/ELISA IgG (78.0%), and Snibe Maglumi IgG (median 78.0%). However, confidence intervals overlapped for several assays. The IgM results were variable, with the Wantai IgM ELISA showing the highest sensitivity (82.7%) and specificity (99%). The rate of seropositivity increased with time from symptom onset and symptom severity.

Immunity to vaccine-preventable diseases among paediatric healthcare workers in Denmark, 2019.

BackgroundHealthcare workers (HCW) have been identified as index cases in disease outbreaks of vaccine-preventable diseases (VPD) in hospitals.AimWe investigated whether Danish paediatric HCW were protected against selected serious VPD.MethodsWe included 90% of staff members from two paediatric departments. All 555 HCW (496 women) supplied a blood sample for serology and filled in a questionnaire. Antibodies were measured with enzyme immunoassay against measles, mumps, rubella (MMR), varicella zoster, pertussis toxin and diphtheria toxin.ResultsProtective levels of IgG were found for measles (90.3%), mumps (86.5%), rubella (92.3%), varicella (98.6%) and diphtheria (80.5%). We found seropositivity for all three MMR components in 421 (75.9%) HCW, lowest in those younger than 36 years (63.3%). Only 28 (5%) HCW had measurable IgG to pertussis. HCW with self-reported immunity defined as previous infection or vaccination, had protective levels of IgG against measles, mumps, rubella and varicella in 87.4-98.8% of cases, not significantly higher than in those not reporting immunity. Previous history of disease had a high positive predictive value (PPV) of 96.8-98.8%. The PPV for previous vaccination ranged from 82.5% to 90.3%. In contrast, negative predictive values of self-reported history of disease and vaccination were remarkably low for all diseases.ConclusionThe immunity gaps found primarily in young HCW indicate a need for a screening and vaccination strategy for this group. Considering the poor correlation between self-reported immunity and seropositivity, efforts should be made to check HCW's immune status in order to identify those who would benefit from vaccination.

The impact and prevalence of SARS-CoV-2 in patients with head and neck cancer and acute upper airway infection in a tertiary otorhinolaryngology referral center in Denmark.

PURPOSE: To determine the prevalence of SARS-CoV-2 at a Danish tertiary referral otorhinolaryngology clinic during the first wave of the COVID-19 pandemic among patients with suspected acute upper airway infection (UAI) and patients operated for head and neck cancer (HNC), respectively. To monitor changes in the number of patient encounters for acute UAI and the number of referrals for the workup of HNC. TRIAL REGISTRATION: NCT-04356560 (Clinicaltrials.gov). METHODS: Prospective enrolled case series of all patients with suspected acute UAI (n = 88) and of patients undergoing surgery for HNC (n = 96), respectively, from March 23rd to May 5th, 2020, at a public tertiary referral otorhinolaryngology clinic in Denmark. SARS-CoV-2 was diagnosed with nasopharyngeal and oropharyngeal swabbing. Patients with suspected acute UAI had symptoms and definitive diagnoses registered in a database. Trends in the number of referrals and patient encounters were retrieved from an electronic patient journal system and analyzed retrospectively. RESULTS: Eighty-eight patients with acute UAI were enrolled including 55 men and 34 women, median age of 31 years (range: 10 months to 82 years). One patient (1.1%) tested positive. Among 96 patients operated for HNC, zero tested positive. The number of referrals for HNC workup, and patient encounters for peritonsillar abscesses, decreased markedly in the first 3 weeks. CONCLUSION: The prevalence of SARS-CoV-2 during the first 6 weeks of the first wave was minimal among patients with acute UAI and zero among patients operated for HNC. The decrease in referrals for the workup of HNC may increase time to treatment initiation and patient morbidity.

Evaluation of an electronic, patient-focused management system aimed at preventing cytomegalovirus disease following solid organ transplantation.

BACKGROUND: Cytomegalovirus (CMV) infection is common among solid organ transplant (SOT) recipients and may cause CMV disease. To optimize the implementation of existing prevention strategies, the Management of Post-transplant Infections in Collaborating Hospitals (MATCH) program was developed. Two key performances of MATCH (diagnosing CMV infection at low viral load (VL) and before the onset of CMV disease) were assessed prior to, during and after the implementation of MATCH. METHODS: The MATCH program included a personalized surveillance plan, prophylaxis and preemptive therapy determined by the recipient's risk of CMV infection. The plan was composed through predefined algorithms and implemented through harvesting of real-time data from medical records. Risk of CMV disease was compared for recipients transplanted during and after vs prior to the implementation of MATCH. Lung and non-lung transplants were analyzed separately. RESULTS: A total of 593, 349, 520, and 360 SOT recipients were transplanted before (2007-2010), during (2011-2012), early after (2013-2015), and late after (2016-2017) implementation of MATCH with an observed reduction of diagnostic VL (P < .001) over time. Risk of CMV disease was reduced among non-lung transplant recipients transplanted during (adjusted hazard ratios [95% CI] 0.15 [0.04-0.54], P = .003), early after (aHR 0.27 [0.11-0.63], P = .003), and late after (aHR 0.17 [0.06-0.52], P = .002) compared with prior to MATCH. No significant change was observed among lung transplants. CONCLUSION: Implementation of CMV preventive strategies through MATCH was associated with a reduced risk of CMV disease among non-lung transplant recipients. Furthermore, the limitations of VL as a sole indicator for CMV disease in lung transplants were emphasized.

Hyaluronic Acid Assays: Turbidimetric or Enzyme-Based Immune Assay? A Method Comparison Study.

BACKGROUD: Hyaluronic acid (HA) is proposed as a marker of functional liver capacity. The aim of the present study was to compare a new turbidimetric assay for measuring HA with the current standard method. METHODS: HA was measured by a particle-enhanced turbidimetric immunoassay (PETIA) and enzyme-linked immunosorbent assay (ELISA) in a 40-sample dilution series and 39 intensive care unit (ICU) patients. Agreement was assessed with Bland-Altman's method. RESULTS: In the ICU patients, the median HA concentration was 159.0 ng/ml (interquartile range (IQR) 117.5-362.5 ng/ml) with ELISA and 157.5 ng/ml (IQR 92.5-359.6 ng/ml) with PETIA. The mean difference was 12.88 ng/ml (95% CI, -4.3 to 30.1 ng/ml, P = 0.14) and the 95% limits of agreement were -91.17 to 116.9 ng/ml. In the dilution series, the mean difference was -59.26 ng/ml (95% CI, -74.68 to 43.84 ng/ml, P < 0.0001) and the 95% limits of agreement were 35.23 to -153.8 ng/ml. CONCLUSION: We found random variation between the PETIA and ELISA test that could affect performance in a clinical context, but only to a lesser extent in a research context. The new clinical biochemistry assay for HA determination will allow for large studies of the clinical utility of HA.

Differences in bacterial saliva profile between periodontitis patients and a control cohort.

AIM: Periodontitis is a multifactorial disease in which subgingival bacteria play an important role in the pathogenesis of the disease. The objective of this study was to determine if periodontitis is associated with a characteristic salivary bacterial profile. This was accomplished by comparing the bacterial profile of saliva from subjects with chronic periodontitis with that of saliva from a control cohort. MATERIALS AND METHODS: Stimulated saliva samples from 139 chronic periodontitis patients and 447 samples from a control cohort were analysed using the Human Oral Microbe Identification Microarray (HOMIM). Frequency and levels (mean HOMIM-value) of around 300 bacterial taxa/clusters in samples were used as parameters for investigation. Differences at taxon/cluster values between groups were analysed using Mann-Whitney U-test with Benjamini-Hochberg correction for multiple comparisons. Principal component analysis was used to visualize bacterial community profiles obtained by the HOMIM. RESULTS: Eight bacterial taxa, including putative periodontal pathogens as Parvimonas micra and Filifactor alocis, and four bacterial clusters were identified statistically more frequently and at higher levels in samples from periodontitis patients than in samples from the control cohort. These differences were independent of the individuals' smoking status. CONCLUSIONS: Periodontitis is associated with a characteristic bacterial profile of saliva different from that of a control cohort.

Robust immune response to COVID-19 vaccination in the island population of Greenland.

BACKGROUND: In Greenland, the COVID-19 pandemic was characterised by a late onset of community transmission and a low impact on the healthcare system, hypothesised as being partly due to a high uptake of vaccinations. To underpin this description, we aimed to assess the SARS-CoV-2 immune response post-vaccination in a Greenlandic population. METHODS: In this observational cohort study, we included 430 adults in Greenland who had received a complete two-dose SARS-CoV-2 vaccination at enrolment. The total plasma SARS-CoV-2 spike glycoprotein Ig antibodies (S-Ab) induced by either the BNT162b2 or mRNA-1273 vaccine, was measured up to 11 months after the second vaccine dose. In addition, total salivary S-Abs were examined in 107 participants, and the T-cell response to the spike glycoprotein was assessed in 78 participants out of the entire study cohort. RESULTS: Here we demonstrate that two months after the second vaccine dose, 96% of participants have protective plasma S-Ab levels. By 11 months, 98% have protective levels, with prior SARS-CoV-2 infection particularly enhancing S-Ab levels by 37% (95% CI 25-51%). Among individuals aged 60 years and older, we observe a 21% (95% CI 7-33%) reduction in antibody response. Total salivary S-Ab levels are detectable in all participants and significantly correlate with plasma levels. Moreover, all participants exhibit a robust SARS-CoV-2-specific T-cell response 11 months post-primary vaccination. CONCLUSIONS: Our findings show that Greenlanders exhibit a robust and lasting immune response, both humoral and cellular, comparable to other population groups up to at least 11 months after the second vaccine dose. These results corroborate the hypothesis that vaccines contributed to the mild impact of the COVID-19 pandemic in the Greenlandic population.

Effective public health measures were crucial to protect Greenland's vulnerable population against the COVID-19 pandemic. Vaccines were particularly important, although their effectiveness in Greenland's unique and isolated population had not been explored. Our aim was to determine the COVID-19 vaccines' immunological response as a measure of protection among Greenlanders. By measuring antibody levels and immune cell activity, we demonstrate that over nine out of ten Greenlanders remained well protected by COVID-19 vaccines up to 11 months after their second vaccine dose, although older adults were less well protected. Prior COVID-19 infection or a booster dose enhanced protection against severe disease. These findings provide valuable insights for Greenland and similar ancestral and geographical populations, aiding in their ongoing vaccination strategies and future pandemic preparedness.

Prospective screening for monkeypox infection among users of HIV pre-exposure prophylaxis in Denmark.

INTRODUCTION: During the 2022 outbreak of mpox (previously called monkeypox), which primarily affected Gay, Bisexual, and other Men who have Sex with Men (GBMSM), testing was mainly limited to individuals with symptoms of infection. Although sporadic cases of mpox continue to be diagnosed in Denmark, the feasibility of screening asymptomatic high-risk populations, such as those using HIV pre-exposure prophylaxis (PrEP), is still unknown. METHODS: During the autumn of 2022, a rectal swab test for mpox PCR was included in the routine sexually transmitted infections (STI) screening for PrEP users. RESULTS: The screening included 224 asymptomatic men with a median age of 36.5 years. One patient (0.4%) tested positive for mpox. Ten (4.5%) and nine (4.0%) had chlamydia and gonorrhea, respectively. DISCUSSION: Our study demonstrates that screening for mpox is feasible in two Danish PrEP clinics.

Exploring the dynamics of COVID-19 in a Greenlandic cohort: Mild acute illness and moderate risk of long COVID.

Objectives: This study aimed to explore how the Greenlandic population experienced the course of both acute and long-term COVID-19. It was motivated by the unique epidemiologic situation in Greenland, with delayed community transmission of SARS-CoV-2 relative to the rest of the world. Methods: In a survey among 310 Greenlandic adults, we assessed the association between previous SARS-CoV-2 infection and overall health outcomes by administering three repeated questionnaires over 12 months after infection, with a response rate of 41% at the 12-month follow-up. The study included 128 individuals with confirmed SARS-CoV-2 infection from January/February 2022 and 182 test-negative controls. Participants were recruited through personal approaches, phone calls, and social media platforms. Results: A total of 53.7% of 162 participants who were test-positive recovered within 4 weeks and 2.5% were hospitalized due to SARS-CoV-2. The most common symptoms were fatigue and signs of mild upper respiratory tract infection. Less than 5% reported sick leave above 2 weeks after infection. Compared with participants who were test-negative, there was an increased risk of reporting fatigue (risk differences 25.4%, 95% confidence interval 8.8-44.0) and mental exhaustion (risk differences 23.4%, 95% confidence interval 4.8-42.2) up to 12 months after a positive test. Conclusions: Our results indicate that during a period dominated by the Omicron variant, Greenlanders experienced a mild acute course of COVID-19, with quick recovery, minimizing the impact on sick leave. Long COVID may be present in Greenlanders, with symptoms persisting up to 12 months after infection. However, it is important to consider the small sample size and modest response rate as limitations when interpreting the results.

Immunogenicity and reactogenicity following MMR vaccination in 5-7-month-old infants: a double-blind placebo-controlled randomized clinical trial in 6540 Danish infants.

Background: Measles is a highly contagious viral disease. Vaccinated mothers transfer fewer antibodies during pregnancy, resulting in shortened infant immunity. Earlier primary vaccination might avert the gap in protection. Methods: Healthy 5-7-month-old Danish infants were assigned in a 1:1 ratio to M-M-RVaxPro or placebo (solvent) in a double-blind, randomized trial between April 15, 2019 and November 1, 2021 (ClinicalTrials.govNCT03780179, EudraCT 2016-001901-18). Eligibility criteria were birth weight >1000 g and gestational age ≥32 weeks.Immunogenicity was measured by plaque reduction neutralization test (PRNT) and IgG ELISA before intervention, four weeks after intervention and routine MMR. Reactogenicity data were collected for six weeks and measured by hazard ratios (HR). Findings: 647 and 6540 infants participated in the immunogenicity and reactogenicity study, respectively; 87% and 99% completed follow-up. After early MMR, seroprotection rates (SPRs) were 47% (13%) in measles PRNT; 28% (2%), 57% (8%) in mumps and rubella IgG (placebo). For measles PRNT, geometric mean ratio was 4.3 (95% CI: 3.4-5.3) between randomization groups after intervention and 1.5 (95% CI: 1.3-1.9) after routine MMR.Reactogenicity was independent of randomization (HR, 1.0; 95% CI: 0.9-1.1). Severe adverse events occurred in 25 infants (HR, 1.8; 95% CI: 0.8-4.0); none deemed vaccine related. Interpretation: Early MMR elicited low SPRs but did not negatively impact short-term responses to a subsequent MMR. MMR at 5-7 months was safe and not associated with higher rates of reactogenicity than placebo. Funding: Innovation Fund Denmark.