Emergence of enterovirus D68 in a Norwegian paediatric population 2012-2022

BackgroundEnterovirus D68 (EV-D68) primarily causes respiratory infection, occasionally manifesting with neurological symptoms. Outbreak reports have been published from various countries including Norway, but a longitudinal study on EV-D68 prevalence in Northern Europe is lacking.MethodsRespiratory samples from children ≤14 years received at Oslo University Hospital in the years 2012-2022 were examined for EV-D68. Samples from 2012-2015 were retrospectively screened using a semi-specific RT-PCR, with positive samples confirmed by an EV-D68 specific RT-PCR. Samples from 2016-2022 underwent routine diagnostics with the EV-D68 specific RT-PCR.ResultsAmong the 22,911 samples tested, EV-D68 was detected in 338 samples (324 patients). Most EV-D68 cases occurred in August to December. The highest detection rate was recorded in 2014, 2016 and 2022 (6.0%, 7.8% and 6.6% of samples from August-December). Lower frequencies were observed in 2018 and 2019 (1.0% and 2.4%), and in the years before the 2014 outbreak (2012: 1.3%, 2013: 0.8%). Few cases were identified in 2020-2021. Children aged 0-1 years accounted for 40%, and 0-4 years for 78%, of the EV-D68 positive patients. Most of the patients with EV-D68 (83%) were hospitalised.DiscussionAlso in Norway, EV-D68 has caused outbreaks with significant disease burden, especially among the youngest children. The detection rate varies, with a trend towards biennial outbreaks, except for low numbers in 2018 and during the COVID-19 restrictions (2020-2021). Due to its potential for severe respiratory illness and significant neurological complications, conducting EV-D68 testing is essential both for diagnosing clinically suspected cases, and for monitoring the disease burden

No association between disease severity and respiratory syncytial virus subtypes RSV-A and RSV-B in hospitalized young children in Norway.

ObjectiveThere is conflicting evidence whether subtypes of Respiratory syncytial virus have different seasonality or are differentially associated with clinical severity. We aimed to explore the associations between disease severity and RSV subtypes RSV-A and RSV-B and to describe the circulation of RSV subtypes pattern by season and age.MethodsActive prospective hospital surveillance for RSV-A and RSV-B in children ResultsBoth RSV-A and B were found to co-circulate throughout all three study seasons, and no clear seasonal pattern was identified. Likewise, we found no association between sex or measures of severity with RSV-A or RSV-B. There was significantly more RSV-A than RSV-B among children with comorbidities.ConclusionsNo association was found between disease severity or sex and RSV subtypes RSV-A and RSV-B in hospitalized young children in Norway

Observed (A) and predicted (B) CD4 cell count by HIV-1 subtype.

<p>A: Median profiles (numbers on top indicate individuals contributing measurements at each time point), B: based on a piecewise linear mixed model (Non acute infection, without AIDS at cART initiation, boosted PI cART, SC to cART>4 years, previously naïve, 5 log₁₀ c/ml initial viral load, men having sex with men, 30 years old at cART initiation).</p

HIV-1 molecular transmission clusters in nine European countries and Canada: association with demographic and clinical factors

Abstract Background Knowledge of HIV-1 molecular transmission clusters (MTCs) is important, especially in large-scale datasets, for designing prevention programmes and public health intervention strategies. We used a large-scale HIV-1 sequence dataset from nine European HIV cohorts and one Canadian, to identify MTCs and investigate factors associated with the probability of belonging to MTCs. Methods To identify MTCs, we applied maximum likelihood inferences on partial pol sequences from 8955 HIV-positive individuals linked to demographic and clinical data. MTCs were defined using two different criteria: clusters with bootstrap support >75% (phylogenetic confidence criterion) and clusters consisting of sequences from a specific region at a proportion of >75% (geographic criterion) compared to the total number of sequences within the network. Multivariable logistic regression analysis was used to assess factors associated with MTC clustering. Results Although 3700 (41%) sequences belonged to MTCs, proportions differed substantially by country and subtype, ranging from 7% among UK subtype C sequences to 63% among German subtype B sequences. The probability of belonging to an MTC was independently less likely for women than men (OR = 0.66; P < 0.001), older individuals (OR = 0.79 per 10-year increase in age; P < 0.001) and people of non-white ethnicity (OR = 0.44; P < 0.001 and OR = 0.70; P = 0.002 for black and ‘other’ versus white, respectively). It was also more likely among men who have sex with men (MSM) than other risk groups (OR = 0.62; P < 0.001 and OR = 0.69; P = 0.002 for people who inject drugs, and sex between men and women, respectively), subtype B (ORs 0.36–0.70 for A, C, CRF01 and CRF02 versus B; all P < 0.05), having a well-estimated date of seroconversion (OR = 1.44; P < 0.001), a later calendar year of sampling (ORs 2.01–2.61 for all post-2002 periods versus pre-2002; all P < 0.01), and being naïve to antiretroviral therapy at sampling (OR = 1.19; P = 0.010). Conclusions A high proportion (>40%) of individuals belonged to MTCs. Notably, the HIV epidemic dispersal appears to be driven by subtype B viruses spread within MSM networks. Expansion of regional epidemics seems mainly associated with recent MTCs, rather than the growth of older, established ones. This information is important for designing prevention and public health intervention strategies

Cumulative incidence of initial virologic response (A) and virologic failure (B) by HIV-1 subtype.

<p>Numbers below each subfigure indicate numbers of individuals “at risk” (i.e. subjects not responded (A) or failed (B) and under follow-up).</p

HIV-1 Infection in Cyprus, the Eastern Mediterranean European Frontier : A densely sampled transmission dynamics analysis from 1986 to 2012

Since HIV-1 treatment is increasingly considered an effective preventionstrategy, it is important to study local HIV-1 epidemics to formulate tailored preventionpolicies. The prevalence of HIV-1 in Cyprus was historically low until 2005. To investigatethe shift in epidemiological trends, we studied the transmission dynamics of HIV-1 in Cyprususing a densely sampled Cypriot HIV-1 transmission cohort that included 85 percent ofHIV-1-infected individuals linked to clinical care between 1986 and 2012 based on detailedclinical, epidemiological, behavioral and HIV-1 genetic information. Subtyping andtransmission cluster reconstruction were performed using maximum likelihood and Bayesianmethods, and the transmission chain network was linked to the clinical, epidemiological andbehavioral data. The results reveal that for the main HIV-1 subtype A1 and B sub-epidemics,young and drug-naïve HIV-1-infected individuals in Cyprus are driving the dynamics of thelocal HIV-1 epidemic. The results of this study provide a better understanding of thedynamics of the HIV-1 infection in Cyprus, which may impact the development of preventionstrategies. Furthermore, this methodology for analyzing densely sampled transmissiondynamics is applicable to other geographic regions to implement effective HIV-1 preventionstrategies in local settings. © 2018 The Author(s)

HIV-1 Infection in Cyprus, the Eastern Mediterranean European Frontier : A densely sampled transmission dynamics analysis from 1986 to 2012

Since HIV-1 treatment is increasingly considered an effective preventionstrategy, it is important to study local HIV-1 epidemics to formulate tailored preventionpolicies. The prevalence of HIV-1 in Cyprus was historically low until 2005. To investigatethe shift in epidemiological trends, we studied the transmission dynamics of HIV-1 in Cyprususing a densely sampled Cypriot HIV-1 transmission cohort that included 85 percent ofHIV-1-infected individuals linked to clinical care between 1986 and 2012 based on detailedclinical, epidemiological, behavioral and HIV-1 genetic information. Subtyping andtransmission cluster reconstruction were performed using maximum likelihood and Bayesianmethods, and the transmission chain network was linked to the clinical, epidemiological andbehavioral data. The results reveal that for the main HIV-1 subtype A1 and B sub-epidemics,young and drug-naïve HIV-1-infected individuals in Cyprus are driving the dynamics of thelocal HIV-1 epidemic. The results of this study provide a better understanding of thedynamics of the HIV-1 infection in Cyprus, which may impact the development of preventionstrategies. Furthermore, this methodology for analyzing densely sampled transmissiondynamics is applicable to other geographic regions to implement effective HIV-1 preventionstrategies in local settings. © 2018 The Author(s)