Evaluation of the national laboratory-based surveillance system for respiratory syncytial virus in Sweden, 2015-2016.

Background: Most laboratories use RSV PCR but near-patient tests (NPT) performed at paediatric clinics are believed to be increasingly used. Anonymised data on RSV infections has been collected since 1990 in Sweden. No evaluation of Swedish RSV surveillance or use of laboratory testing had previously been performed.

Impact on affected families and society of severe rotavirus infections in Swedish children assessed in a prospective cohort study.

Background: Few prospective cohort studies have estimated the overall impact of severe rotavirus gastroenteritis (RVGE) leading to hospitalization on families and society. We assessed human and economic resources needed to care for an affected average child aged <5 years in Sweden.

Methods: The study was conducted in Astrid Lindgren Children's Hospital which serves approximately 14% of all Swedish children <5 years of age.

Epidemiology of Campylobacter jejuni infections in Sweden, November 2011-October 2012: is the severity of infection associated with C. jejuni sequence type?

Background: Campylobacter jejuni is among the most frequent causes of bacterial gastroenteritis in Europe. Over 8,000 C. jejuni multilocus sequence typing sequence types (STs) have been described; ST-21 and ST-45 have been identified as the most frequent types in all human studies so far.

Six-week follow-up after HIV-1 exposure: a position statement from the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy.

In 2014 the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy (RAV) conducted a review and analysis of the state of knowledge on the duration of follow-up after exposure to human immunodeficiency virus (HIV). Up until then a follow-up of 12 weeks after exposure had been recommended, but improved tests and new information on early diagnosis motivated a re-evaluation of the national recommendations by experts representing infectious diseases and microbiology, county medical officers, the RAV, the Public Health Agency, and other national authorities. Based on the current state of knowledge the Public Health Agency of Sweden and the RAV recommend, starting in April 2015, a follow-up period of 6 weeks after possible HIV-1 exposure, if HIV testing is performed using laboratory-based combination tests detecting both HIV antibody and antigen.

Role of Sequencing the Measles Virus Hemagglutinin Gene and Hypervariable Region in the Measles Outbreak Investigations in Sweden During 2013-2014.

Introduction: It is increasingly difficult to differentiate measles viruses (MeVs) relating to certain outbreaks on the basis of the nucleoprotein (N) gene sequence only, as the diversity of circulating MeV strains has decreased. We studied genomic regions that could provide better molecular discrimination between epidemiologically linked and unlinked MeV variants identified in Sweden during 2013-2014.

Methods: The hemagglutinin (H) gene and hypervariable region between the fusion and matrix genes (MF-HVR) from 53 MeV-positive samples were amplified and sequenced.

Risk of HIV transmission from patients on antiretroviral therapy: a position statement from the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy.

The modern medical treatment of HIV with antiretroviral therapy (ART) has drastically reduced the morbidity and mortality in patients infected with this virus. ART has also been shown to reduce the transmission risk from individual patients as well as the spread of the infection at the population level. This position statement from the Public Health Agency of Sweden and the Swedish Reference Group for Antiviral Therapy is based on a workshop organized in the fall of 2012.

Burden of severe rotavirus disease leading to hospitalization assessed in a prospective cohort study in Sweden.

Background: The aim of this prospective cohort study was to estimate the burden of severe disease caused by rotavirus-induced gastroenteritis in Swedish children aged < 5 y.

Methods: Rotavirus-positive children admitted to hospitals serving 3 geographical regions with 155,838 children aged < 5 y, were offered inclusion in this 1-year study. Rotavirus strains identified were genotyped using multiplex PCR.

Pandemic influenza A(H1N1)pdm09 seroprevalence in Sweden before and after the pandemic and the vaccination campaign in 2009.

The immunity to pandemic influenza A(H1N1)pdm09 in Sweden before and after the outbreaks in 2009 and 2010 was investigated in a seroepidemiological study. Serum samples were collected at four time points: during 2007 (n = 1968), in October 2009 (n = 2218), in May 2010 (n = 2638) and in May 2011 (n = 2513) and were tested for hemagglutination inhibition (HI) antibodies. In 2007, 4.

Acute sleep deprivation has no lasting effects on the human antibody titer response following a novel influenza A H1N1 virus vaccination.

Background: Experimental studies in humans have yielded evidence that adaptive immune function, including the production of antigen-specific antibodies, is distinctly impaired when sleep is deprived at the time of first antigen exposure. Here we examined the effects of a regular 24-hour sleep-wake cycle (including 8 hours of nocturnal sleep) and a 24-hour period of continuous wakefulness on the 7-week antibody production in 11 males and 13 females in response to the H1N1 (swine flu) virus vaccination. The specific antibody titer in serum was assayed by the hemagglutination inhibition test on the days 5, 10, 17, and 52 following vaccination.

Longitudinal clearance of seasonal influenza A viral RNA measured by real-time polymerase chain reaction in patients identified at a hospital emergency department.

To study influenza virus shedding during acute infection, viral load was longitudinally measured by quantitative PCR in nasal flocked swabs from patients with seasonal H3N2 influenza at a Swedish emergency department, including both hospitalized patients and outpatients. Influenza A was detected in 65/184 patients. Sampling was repeated every 3-4 days in 45 patients, with the aim of continuing sampling until day 12 after disease onset.

Monitoring of herpes simplex virus DNA types 1 and 2 viral load in cerebrospinal fluid by real-time PCR in patients with herpes simplex encephalitis.

A quantitative polymerase chain reaction (PCR) assay was evaluated retrospectively on 92 cerebrospinal fluid (CSF) samples from 29 patients with herpes simplex virus (HSV) encephalitis with the aim to study if the concentration of HSV genomes can be used as a prognostic marker and for monitoring of antiviral therapy. The results were compared to those obtained previously by nested PCR, and the numbers of HSV genomes/ml were evaluated in correlation to patient outcome and treatment. The aims were to compare the sensitivity of a conventional nested PCR to a quantitative PCR, to investigate the range of HSV genome concentration in initial samples and to evaluate possible relationships between the HSV DNA concentrations in CSF, neopterin levels, and outcome of disease.

Genetic diversity among food-borne and waterborne norovirus strains causing outbreaks in Sweden.

A total of 101 food-borne and waterborne outbreaks that were caused by norovirus and that resulted in more than 4,100 cases of illness were reported to the Swedish Institute for Infectious Disease Control from January 2002 to December 2006. Sequence and epidemiological data for isolates from 73 outbreaks were analyzed. In contrast to health care-related outbreaks, no clear seasonality could be observed.

Prognostic value of intrathecal antibody production and DNA viral load in cerebrospinal fluid of patients with herpes simplex encephalitis.

Herpes simplex encephalitis is a devastating disease. In the early 1980s our group conducted a nationwide clinical trial of acyclovir versus vidarabine in patients with herpes simplex encephalitis in whom intrathecal herpes simplex virus (HSV) antibodies were assayed. The purpose of this study was to investigate if antibody levels and viral load correlate with outcome in herpes simplex encephalitis.

Encephalitis after influenza in Sweden 1987-1998: a rare complication of a common infection.

The aim of this study was to investigate the incidence of influenza-related encephalitis in Sweden during 11.5 years. Studies from Japan report an increased incidence of influenza-related encephalitis/encephalopathy.

Molecular characterization of highly pathogenic H5N1 avian influenza viruses isolated in Sweden in 2006.

Background: The analysis of the nonstructural (NS) gene of the highly pathogenic (HP) H5N1 avian influenza viruses (AIV) isolated in Sweden early 2006 indicated the co-circulation of two sub-lineages of these viruses at that time. In order to complete the information on their genetic features and relation to other HP H5N1 AIVs the seven additional genes of twelve Swedish isolates were amplified in full length, sequenced, and characterized.

Results: The presence of two sub-lineages of HP H5N1 AIVs in Sweden in 2006 was further confirmed by the phylogenetic analysis of approximately the 95% of the genome of twelve isolates that were selected on the base of differences in geographic location, timing and animal species of origin.

Langerhans cell histiocytosis reveals a new IL-17A-dependent pathway of dendritic cell fusion.

IL-17A is a T cell-specific cytokine that is involved in chronic inflammations, such as Mycobacterium infection, Crohn's disease, rheumatoid arthritis and multiple sclerosis. Mouse models have explained the molecular basis of IL-17A production and have shown that IL-17A has a positive effect not only on granuloma formation and neurodegeneration through unknown mechanisms, but also on bone resorption through Receptor activator of NF-kappaB ligand (RANKL) induction in osteoblasts. Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology, lacking an animal model, that cumulates symptoms that are found separately in various IL-17A-related diseases, such as aggressive chronic granuloma formation, bone resorption and soft tissue lesions with occasional neurodegeneration.

A real-time PCR assay for the monitoring of influenza A virus in wild birds.

A screening system including a new real-time PCR assay for the monitoring of influenza A virus in wild birds was developed. The real-time PCR assay uses SYBR green chemistry and the primers are targeting the matrix gene of influenza A virus. The performance of the assay was compared with two other assays, one assay also using SYBR green chemistry and one assay using TaqMan chemistry, i.

Virus-induced transcriptional activation of host FUT genes associated with neo-expression of Ley in cytomegalovirus-infected and sialyl-Lex in varicella-zoster virus-infected diploid human cells.

Cell surface carbohydrate structures including sialyl-Lewis X (sLe(x)) and Lewis Y (Le(y)) are important ligands in normal and malignant tissues. The aim here was to determine the possible influence on the expression of such antigens by two viruses varicella-zoster virus (VZV) and cytomegalovirus (CMV) involved in persistent infections of humans. We found that infection of human diploid fibroblasts with both viruses resulted in transcriptional activation of several fucosyltransferase (FUT) genes that were either dormant or expressed at low levels in uninfected cells.

Human herpes virus DNA is rarely detected in non-UV light-associated primary malignant melanomas of mucous membranes.

Background: UV-radiation is the most important causative factor for malignant melanomas of the skin. However, this is not the case for melanomas on sun-sheltered body surfaces. The aim of this study was to investigate if human herpes virus DNA could be found in malignant melanomas in sun-sheltered body areas and if these viruses play a role in the development of extracutaneous melanomas.

Point mutations induced by foscarnet (PFA) in the human cytomegalovirus DNA polymerase.

Background: In vitro selection of viruses with decreased drug susceptibility is a useful tool for mapping drug resistance-associated alterations, evaluating cross-resistance profiles, and elucidating molecular mechanisms of antiviral activity.

Objectives: To provide data on mechanisms of selective drug action and features of drug resistance that may be clinically important.

Study Design: Foscarnet (PFA) and ganciclovir (GCV) were used to induce mutants of the human cytomegalovirus (HCMV) Towne strain.