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1.
Health Promot Int ; 36(6): 1566-1577, 2021 Dec 23.
Article En | MEDLINE | ID: mdl-33604664

Viral infections have a large share in human morbidity and mortality. Next to vaccinations and hygiene measures, health education plays a role in preventing infections. Social scientists argue that empowerment should be included in health education, as increasing knowledge is insufficient to achieve sustainable behaviour change. Within the international education module 'Viruskenner', primary school students learn how to prevent virus infections by identifying health risks and developing interventions. This qualitative formative study explored to what extent Viruskenner creates conditions in which empowerment processes can arise and take place in the Netherlands and Suriname. Indicators of empowerment, as defined in the literature and placed in the attitude, social influence, and self-efficacy model, were assessed during semi-structured interviews (n = 24) with students, parents, teachers and facilitators. We conclude that Viruskenner is successful in creating conditions for empowerment processes to arise and take place, specifically in attitude and self-efficacy. According to interviewees, the module raised students' motivation, skills and confidence to take action to improve health behaviour. Educators played a stimulating role in the participatory setting in both countries, while content relevance and community involvement differed between the Netherlands and Suriname. These outcomes could improve this module and possibly other health education programmes.


Schools , Virus Diseases , Child , Health Education , Humans , Power, Psychological , Students
2.
Nat Commun ; 12(1): 267, 2021 01 11.
Article En | MEDLINE | ID: mdl-33431879

Key questions in COVID-19 are the duration and determinants of infectious virus shedding. Here, we report that infectious virus shedding is detected by virus cultures in 23 of the 129 patients (17.8%) hospitalized with COVID-19. The median duration of shedding infectious virus is 8 days post onset of symptoms (IQR 5-11) and drops below 5% after 15.2 days post onset of symptoms (95% confidence interval (CI) 13.4-17.2). Multivariate analyses identify viral loads above 7 log10 RNA copies/mL (odds ratio [OR] of 14.7 (CI 3.57-58.1; p < 0.001) as independently associated with isolation of infectious SARS-CoV-2 from the respiratory tract. A serum neutralizing antibody titre of at least 1:20 (OR of 0.01 (CI 0.003-0.08; p < 0.001) is independently associated with non-infectious SARS-CoV-2. We conclude that quantitative viral RNA load assays and serological assays could be used in test-based strategies to discontinue or de-escalate infection prevention and control precautions.


COVID-19/diagnosis , COVID-19/virology , SARS-CoV-2 , Virus Shedding , Aged , COVID-19 Testing , Female , Humans , Male , Middle Aged , Multivariate Analysis , Odds Ratio , RNA, Viral , Respiratory System/virology , Viral Load
3.
J Virol ; 95(3)2021 01 13.
Article En | MEDLINE | ID: mdl-33115870

Human noroviruses are the most common nonbacterial cause of gastroenteritis outbreaks, with new variants and genotypes frequently emerging. The origin of these new viruses is unknown; however, animals have been proposed as a potential source, as human noroviruses have been detected in animal species. Here, we investigated the potential of animals to serve as a reservoir of human noroviruses by testing norovirus attachment to formalin-fixed intestinal tissues of a range of potential reservoir animals. We set up a novel method to study norovirus binding using fluorescein isothiocyanate (FITC)-labeled virus-like particles (VLPs). In humans, noroviruses interact with histo-blood group antigens (HBGAs), carbohydrates that are expressed, among others, on the epithelial lining of the gastrointestinal tract. In animals, this interaction is not well understood. To test if virus binding depends on HBGAs, we characterized the HBGA phenotype in animal tissues by immunohistochemistry. With the exception of the black-headed gull and the straw-colored fruitbat, we observed the attachment of several human norovirus genotypes to the intestinal epithelium of all tested animal species. However, we did not find an association between the expression of a specific HBGA phenotype and virus-like particle (VLP) attachment. We show that selected human noroviruses can attach to small-intestinal tissues across species, supporting the hypothesis that human noroviruses can reside in an animal reservoir. However, whether this attachment can subsequently lead to infection needs to be further assessed.IMPORTANCE Noroviruses are a major cause of acute gastroenteritis in humans. New norovirus variants and recombinants (re)emerge regularly in the human population. From animal experiments and surveillance studies, it has become clear that at least seven animal models are susceptible to infection with human strains and that domesticated and wild animals shed human noroviruses in their feces. As virus attachment is an important first step for infection, we used a novel method utilizing FITC-labeled VLPs to test for norovirus attachment to intestinal tissues of potential animal hosts. We further characterized these tissues with regard to their HBGA expression, a well-studied norovirus susceptibility factor in humans. We found attachment of several human strains to a variety of animal species independent of their HBGA phenotype. This supports the hypothesis that human strains could reside in an animal reservoir.


Blood Group Antigens/metabolism , Caliciviridae Infections/virology , Disease Models, Animal , Gastroenteritis/virology , Intestinal Mucosa/virology , Norovirus/physiology , Virus Attachment , Amino Acid Sequence , Animals , Caliciviridae Infections/metabolism , Caliciviridae Infections/pathology , Feces/virology , Gastroenteritis/metabolism , Gastroenteritis/pathology , Humans , Intestinal Mucosa/metabolism , Sequence Homology
4.
PLoS Negl Trop Dis ; 14(10): e0008784, 2020 10.
Article En | MEDLINE | ID: mdl-33048925

BACKGROUND: Although preventable by vaccination for more than a century, rabies virus still causes numerous fatalities every year. To determine antibody levels in humans, blood collected with a finger prick and applied on dried blood spot (DBS) cards is an alternative for venipuncture. The use of DBS is specifically valuable in remote areas, as it is easy to perform, store and transport. Therefore, the technique is frequently used for epidemiological studies of tropical diseases. Up to present, determination of rabies virus antibody levels on human DBS has not been validated. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the use of human DBS for rabies serology and analyzed 99 pre- or post-vaccination serum and DBS samples with a fluorescent antibody virus neutralization test (FAVNt), which is the gold standard to detect protective antibody levels, and a Bio-Rad Platelia Rabies II ELISA. Sensitivity and specificity of DBS eluates tested with the FAVNt were 97% and 92%, respectively and 87% and 96% when tested with the Platelia-II ELISA. Antibody levels measured in serum with the FAVNt, correlated best with antibody levels measured in DBS with the FAVNt (R = 0.88). CONCLUSIONS/SIGNIFICANCE: This is the first study that applies DBS for reliable detection of human antibodies against rabies virus. Both the FAVNt and Platelia-II ELISA demonstrate an acceptable performance on DBS, providing opportunities for rabies serology in remote areas. This technique could drastically ease studies evaluating (novel) rabies vaccination strategies and monitoring persisting immunity in humans at risk, living in rabies endemic regions.


Antibodies, Viral/blood , Dried Blood Spot Testing/methods , Rabies virus/immunology , Rabies/blood , Humans , Rabies/diagnosis , Rabies/virology , Rabies virus/isolation & purification , Sensitivity and Specificity
5.
Emerg Infect Dis ; 23(1): 87-91, 2017 01.
Article En | MEDLINE | ID: mdl-27983498

A norovirus was detected in harbor porpoises, a previously unknown host for norovirus. This norovirus had low similarity to any known norovirus. Viral RNA was detected primarily in intestinal tissue, and specific serum antibodies were detected in 8 (24%) of 34 harbor porpoises from the North Sea.


Caliciviridae Infections/epidemiology , Caliciviridae Infections/veterinary , Genome, Viral , Norovirus/genetics , Phylogeny , Animals , Caliciviridae Infections/virology , Intestines/pathology , Intestines/virology , Norovirus/classification , North Sea/epidemiology , Phocoena/virology , RNA-Dependent RNA Polymerase/genetics , Viral Proteins/genetics
7.
PLoS One ; 11(5): e0155531, 2016.
Article En | MEDLINE | ID: mdl-27171421

Herpes simplex encephalitis (HSE) is a life-threatening complication of herpes simplex virus (HSV) infection. Acyclovir (ACV) is the antiviral treatment of choice, but may lead to emergence of ACV-resistant (ACVR) HSV due to mutations in the viral UL23 gene encoding for the ACV-targeted thymidine kinase (TK) protein. Here, we determined the prevalence of intrathecal ACVR-associated HSV TK mutations in HSE patients and compared TK genotypes of sequential HSV isolates in paired cerebrospinal fluid (CSF) and blister fluid of mucosal HSV lesions. Clinical samples were obtained from 12 HSE patients, encompassing 4 HSV type 1 (HSV-1) and 8 HSV-2 encephalitis patients. HSV DNA load was determined by real-time PCR and complete HSV TK gene sequences were obtained by nested PCR followed by Sanger sequencing. All HSV-1 HSE patients contained viral TK mutations encompassing 30 unique nucleotide and 13 distinct amino acid mutations. By contrast, a total of 5 unique nucleotide and 4 distinct amino acid changes were detected in 7 of 8 HSV-2 patients. Detected mutations were identified as natural polymorphisms located in non-conserved HSV TK gene regions. ACV therapy did not induce the emergence of ACVR-associated HSV TK mutations in consecutive CSF and mucocutaneous samples of 5 individual patients. Phenotypic susceptibility analysis of these mucocutaneous HSV isolates demonstrated ACV-sensitive virus in 2 HSV-1 HSE patients, whereas in two HSV-2 HSE patients ACVR virus was detected in the absence of known ACVR-associated TK mutations. In conclusion, we did not detect intrathecal ACVR-associated TK mutations in HSV isolates obtained from 12 HSE patients.


Acyclovir/pharmacology , Drug Resistance, Viral/drug effects , Encephalitis, Herpes Simplex/virology , Herpesvirus 1, Human/physiology , Herpesvirus 2, Human/physiology , Spinal Cord/pathology , Spinal Cord/virology , Adult , Amino Acid Substitution/genetics , Antiviral Agents/pharmacology , Demography , Encephalitis, Herpes Simplex/cerebrospinal fluid , Female , Herpesvirus 1, Human/drug effects , Herpesvirus 1, Human/enzymology , Herpesvirus 1, Human/isolation & purification , Herpesvirus 2, Human/drug effects , Herpesvirus 2, Human/enzymology , Herpesvirus 2, Human/isolation & purification , Humans , Male , Middle Aged , Phenotype , Polymorphism, Single Nucleotide/genetics , Prevalence , Thymidine Kinase/genetics , Young Adult
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