Measles.

Measles is a highly contagious, potentially fatal, but vaccine-preventable disease caused by measles virus. Symptoms include fever, maculopapular rash, and at least one of cough, coryza, or conjunctivitis, although vaccinated individuals can have milder or even no symptoms. Laboratory diagnosis relies largely on the detection of specific IgM antibodies in serum, dried blood spots, or oral fluid, or the detection of viral RNA in throat or nasopharyngeal swabs, urine, or oral fluid. Complications can affect many organs and often include otitis media, laryngotracheobronchitis, pneumonia, stomatitis, and diarrhoea. Neurological complications are uncommon but serious, and can occur during or soon after the acute disease (eg, acute disseminated encephalomyelitis) or months or even years later (eg, measles inclusion body encephalitis and subacute sclerosing panencephalitis). Patient management mainly involves supportive therapy, such as vitamin A supplementation, monitoring for and treatment of secondary bacterial infections with antibiotics, and rehydration in the case of severe diarrhoea. There is no specific antiviral therapy for the treatment of measles, and disease control largely depends on prevention. However, despite the availability of a safe and effective vaccine, measles is still endemic in many countries and causes considerable morbidity and mortality, especially among children in resource-poor settings. The low case numbers reported in 2020, after a worldwide resurgence of measles between 2017 and 2019, have to be interpreted cautiously, owing to the effect of the COVID-19 pandemic on disease surveillance. Disrupted vaccination activities during the pandemic increase the potential for another resurgence of measles in the near future, and effective, timely catch-up vaccination campaigns, strong commitment and leadership, and sufficient resources will be required to mitigate this threat.

Epidemiological and clinical insights from SARS-CoV-2 RT-PCR crossing threshold values, France, January to November 2020.

BackgroundThe COVID-19 pandemic has led to an unprecedented daily use of RT-PCR tests. These tests are interpreted qualitatively for diagnosis, and the relevance of the test result intensity, i.e. the number of quantification cycles (Cq), is debated because of strong potential biases.AimWe explored the possibility to use Cq values from SARS-CoV-2 screening tests to better understand the spread of an epidemic and to better understand the biology of the infection.MethodsWe used linear regression models to analyse a large database of 793,479 Cq values from tests performed on more than 2 million samples between 21 January and 30 November 2020, i.e. the first two pandemic waves. We performed time series analysis using autoregressive integrated moving average (ARIMA) models to estimate whether Cq data information improves short-term predictions of epidemiological dynamics.ResultsAlthough we found that the Cq values varied depending on the testing laboratory or the assay used, we detected strong significant trends associated with patient age, number of days after symptoms onset or the state of the epidemic (the temporal reproduction number) at the time of the test. Furthermore, knowing the quartiles of the Cq distribution greatly reduced the error in predicting the temporal reproduction number of the COVID-19 epidemic.ConclusionOur results suggest that Cq values of screening tests performed in the general population generate testable hypotheses and help improve short-term predictions for epidemic surveillance.

Prolonged Maternal Shedding and Maternal-fetal Transmission of Measles Virus.

Prolonged measles virus detection in maternal saliva and blood was evidenced in 6 pregnant women. Maternal-fetal transmission was evidenced in 2 of 4 infants who were asymptomatic at birth, 21-24 weeks after maternal infection. Whereas peripartum congenital measles is severe, asymptomatic measles virus vertical transmission can occur earlier in pregnancy.

Factors associated with the emergence of integrase resistance mutations in patients failing dual or triple integrase inhibitor-based regimens in a French national survey.

BACKGROUND: Successful 2-drug regimens (2DRs) for HIV were made possible by the availability of drugs combining potency and tolerability with a high genetic barrier to resistance. How these deal with resistance development/re-emergence, compared with 3DRs, is thus of paramount importance. MATERIALS AND METHODS: A national survey including patients who were either naive or experienced with any 2DR or 3DR but failing integrase strand transfer inhibitor (INSTI)-containing regimens [two consecutive plasma viral load (VL) values >50 copies/mL] was conducted between 2014 and 2019. Genotypic resistance tests were interpreted with the v28 ANRS algorithm. RESULTS: Overall, 1104 patients failing any INSTI-containing regimen (2DRs, n = 207; 3DRs, n = 897) were analysed. Five hundred and seventy-seven (52.3%) patients were infected with a B subtype and 527 (47.3%) with non-B subtypes. Overall, 644 (58%) patients showed no known integrase resistance mutations at failure. In multivariate analysis, factors associated with the emergence of at least one integrase mutation were: high VL at failure (OR = 1.24 per 1 log10 copies/mL increase); non-B versus B subtype (OR = 1.75); low genotypic sensitivity score (GSS) (OR = 0.10 for GSS = 2 versus GSS = 0-0.5); and dolutegravir versus raltegravir (OR = 0.46). Although 3DRs versus 2DRs reached statistical significance in univariate analysis (OR = 0.59, P = 0.007), the variable is not retained in the final model. CONCLUSIONS: This study is one of the largest studies characterizing integrase resistance in patients failing any INSTI-containing 2DR or 3DR in routine clinical care and reveals factors associated with emergence of integrase resistance that should be taken into consideration in clinical management. No difference was evidenced between patients receiving a 2DR or a 3DR.

[Influenza viruses and SARS-CoV-2, are we ready for the future?] / Virus grippaux et Sars-CoV-2, sommes-nous prêts pour le futur ?

Influenza viruses and severe acute respiratory syndrome coronavirus 2 are respiratory viruses with a high potential for evolution. Their circulation must be carefully monitored.. The development of diagnostic tools, as well as the search for universal vaccines and new treatments, are strategic tools in public health that allow us to be ready to face future emergencies.

Surveillance of HIV-1 primary infections in France from 2014 to 2016: toward stable resistance, but higher diversity, clustering and virulence?

OBJECTIVES: Patients with primary HIV-1 infection (PHI) are a particular population, giving important insight about ongoing evolution of transmitted drug resistance-associated mutation (TDRAM) prevalence, HIV diversity and clustering patterns. We describe these evolutions of PHI patients diagnosed in France from 2014 to 2016. METHODS: A total of 1121 PHI patients were included. TDRAMs were characterized using the 2009 Stanford list and the French ANRS algorithm. Viral subtypes and recent transmission clusters (RTCs) were also determined. RESULTS: Patients were mainly MSM (70%) living in the Paris area (42%). TDRAMs were identified among 10.8% of patients and rose to 18.6% when including etravirine and rilpivirine TDRAMs. Prevalences of PI-, NRTI-, first-generation NNRTI-, second-generation NNRTI- and integrase inhibitor-associated TDRAMs were 2.9%, 5.0%, 4.0%, 9.4% and 5.4%, respectively. In a multivariable analysis, age >40 years and non-R5 tropic viruses were associated with a >2-fold increased risk of TDRAMs. Regarding HIV diversity, subtype B and CRF02_AG (where CRF stands for circulating recombinant form) were the two main lineages (56% and 20%, respectively). CRF02_AG was associated with higher viral load than subtype B (5.83 versus 5.40 log10 copies/mL, P=0.004). We identified 138 RTCs ranging from 2 to 14 patients and including overall 41% from the global population. Patients in RTCs were younger, more frequently born in France and more frequently MSM. CONCLUSIONS: Since 2007, the proportion of TDRAMs has been stable among French PHI patients. Non-B lineages are increasing and may be associated with more virulent CRF02_AG strains. The presence of large RTCs highlights the need for real-time cluster identification to trigger specific prevention action to achieve better control of the epidemic.

When a viral eruption hides another one: intrafamilial outbreak of parvovirus B19 and measles virus co-infections: case report.

BACKGROUND: Despite high overall population vaccine coverage, identified clusters of persons refraining from vaccination interfere with pursued measles elimination. Clinical diagnosis of measles is often obvious due to its typical rash. Yet, febrile rashes may occur during many viral infections. Misdiagnosis of a specific primary viral infection may have severe consequences, particularly in immunocompromised subjects or pregnant women. To our knowledge, this case presentation is the first description of a measles and parvovirus B19 coinfection outbreak. Analysis of this outbreak underlines rash diagnosis difficulties and potential serology interpretation pitfalls. This case report is helpful for the clinicians in the context of measles re-emergence and proposes several methods to improve the diagnosis approach. CASE PRESENTATION: We investigated an outbreak of rash in 6 out of 8 Traveler family members presenting to Rennes University Hospital (West of France). Anti-B19V and measles IgM/IgG antibodies were measured and detection of Parvovirus B19 and measles virus genomes were done on blood and/or respiratory samples. Virological investigations finally documented 6 cases of parvovirus B19 infections, including 4 associated with measles. Interestingly, in the four coinfection cases, the rash was typical of B19V primary infection for the two children but typical of measles for the two adults. Clinical diagnosis of rash may be misleading and thorough virological investigations may be required to avoid misdiagnosis. CONCLUSIONS: This investigation first reports an intra-familial outbreak of MeV/B19V coinfections highlighting the high transmissibility of both viruses and the diagnostic challenges of dual rash-associated infections. This report also underlines the potential deleterious consequences of failure to identify measles cases, especially in a community with low vaccination coverage.

Resistance to integrase inhibitors: a national study in HIV-1-infected treatment-naive and -experienced patients.

OBJECTIVES: To describe integrase strand transfer inhibitor (INSTI) resistance profiles and factors associated with resistance in antiretroviral-naive and -experienced patients failing an INSTI-based regimen in clinical practice. METHODS: Data were collected from patients failing an INSTI-containing regimen in a multicentre French study between 2014 and 2017. Failure was defined as two consecutive plasma viral loads (VL) >50 copies/mL. Reverse transcriptase, protease and integrase coding regions were sequenced at baseline and failure. INSTI resistance-associated mutations (RAMs) included in the Agence Nationale de Recherches sur le SIDA genotypic algorithm were investigated. RESULTS: Among the 674 patients, 359 were failing on raltegravir, 154 on elvitegravir and 161 on dolutegravir therapy. Overall, 90% were experienced patients and 389 (58%) patients showed no INSTI RAMs at failure. The strongest factors associated with emergence of at least one INSTI mutation were high VL at failure (OR = 1.2 per 1 log10 copies/mL increase) and low genotypic sensitivity score (GSS) (OR = 0.08 for GSS ≥3 versus GSS = 0-0.5). Patients failing dolutegravir also had significantly fewer INSTI RAMs at failure than patients failing raltegravir (OR = 0.57, P = 0.02) or elvitegravir (OR = 0.45, P = 0.005). Among the 68 patients failing a first-line regimen, 11/41 (27%) patients on raltegravir, 7/18 (39%) on elvitegravir and 0/9 on dolutegravir had viruses with emergent INSTI RAMs at failure. CONCLUSIONS: These results confirmed the robustness of dolutegravir regarding resistance selection in integrase in the case of virological failure in routine clinical care.

Impact of Human Immunodeficiency Virus Type 1 Minority Variants on the Virus Response to a Rilpivirine-Based First-line Regimen.

Background: Minority resistant variants of human immunodeficiency virus type 1 (HIV-1) could influence the virological response to treatment based on nonnucleoside reverse transcriptase inhibitors (NNRTIs). Data on minority rilpivirine-resistant variants are scarce. This study used next-generation sequencing (NGS) to identify patients harboring minority resistant variants to nucleos(t)ide reverse transcriptase inhibitors and NNRTIs and to assess their influence on the virological response (VR). Methods: All the subjects, 541 HIV-1-infected patients started a first-line regimen containing rilpivirine. VR was defined as a HIV-1 RNA load <50 copies/mL at month 6 with continued suppression at month 12. NGS was performed at baseline (retrospectively) on the 454 GS-FLX platform (Roche). Results: NGS revealed resistance-associated mutations accounting for 1% to <5% of variants in 17.2% of samples, for 5%-20% in 5.7% of samples, and for >20% in 29% of samples. We identified 43 (8.8%) and 36 (7.4%) patients who harbored rilpivirine-resistant variants with a 1% sensitivity threshold according to the French National Agency for Research on AIDS and Viral Hepatitis and Stanford algorithms, respectively. The VR was 96.9% at month 12. Detection of minority rilpivirine resistant variants was not associated with virological failure (VF). Multivariate analysis indicated that VF at month 12 was associated with a CD4 count <250 cells/µL at baseline, a slower decrease in viral load at month 3, and rilpivirine resistance at baseline using the Stanford algorithm with a 20% threshold. Conclusions: Minority resistant variants had no impact on the VR of treatment-naive patients to a rilpivirine-based regimen.

Phenotypic analysis of HIV-1 E157Q integrase polymorphism and impact on virological outcome in patients initiating an integrase inhibitor-based regimen.

Objectives: To assess the phenotypic susceptibility of the E157Q polymorphism in HIV-1 integrase (IN) and the virological outcome of patients infected with E157Q-mutated virus initiating an IN inhibitor (INI)-based regimen. Methods: This was a multicentre study assessing IN sequences from INI-naive patients among 17 French HIV clinical centres. E157Q site-directed mutants in pNL4.3 and pCRF02_AG contexts were assessed in a recombinant phenotypic assay. Results: Prevalence of the E157Q polymorphism was 2.7% among 8528 IN sequences from INI-naive patients and its distribution was 1.7%, 5.6% and 2.2% in B, CRF02_AG and various non-B subtypes, respectively. Thirty-nine INI-naive patients with E157Q-mutated virus initiated an INI-based regimen. Among them, 15 had a viral load (VL) <50 copies/mL at initiation and virological suppression was maintained during the first year of follow-up in all but two exhibiting a viral blip. Twenty-four patients had a VL > 50 copies/mL at the time of INI-based regimen initiation. Among them eight were receiving a first-line regimen and the only two patients who did not reach VL < 50 copies/mL at week 24 were receiving elvitegravir. The 16 remaining patients were ART experienced in virological failure with drug-resistant viruses displaying several virological outcomes independently of the genotypic susceptibility score. Phenotypic analyses showed a fold change in EC50 of 0.6, 0.9 and 1.9 for raltegravir, dolutegravir and elvitegravir, respectively, in a subtype B context, and 1.1, 1.9 and 2.4 for raltegravir, dolutegravir and elvitegravir, respectively, in a CRF02_AG context. Conclusions: Assessment of virological response in 39 patients initiating an INI-based regimen with E157Q-mutated virus, in combination with phenotypic analysis, suggests that particular attention should be paid to antiretroviral-naive patients and dolutegravir should be preferentially used in these patients.

Measles outbreak linked to insufficient vaccination coverage in Nouvelle-Aquitaine Region, France, October 2017 to July 2018.

On 30 October 2017, an outbreak of measles started in the Nouvelle-Aquitaine (NA) region in France among Bordeaux University students before spreading to other regions. Until 1 July 2018, 1,101 cases were reported in NA, including 98 complications and two deaths. Cases were related to clusters (e.g. students, healthcare workers) in 16%; 81% of cases were not vaccinated against measles as recommended. Vaccination coverage above herd immunity threshold remains the main preventative outbreak measure.

Mumps virus: a comprehensive review.

Once very common in children, mumps virus infection is now much rarer thanks to vaccination, recommended in the majority of countries in the world. This virus of the family Paramyxoviridae has a marked tropism for glandular tissues which explains the great diversity of pathologies related to this virus, including parotitis, orchitis or meningitis. Due to the lower circulation of the virus, the proportion of infected adults increases. A surveillance system for mumps virus infections at the national and international levels is organized, particularly at the molecular level. In France, it is provided by the national reference center for Measles, Mumps and Rubella. Although it has led to a significant reduction in the number of cases, the long-term effectiveness of mumps vaccination is questionable. The nature of the vaccine strains and the lack of regular stimulation of populations by circulating wild viruses may explain, in part, the decrease in immunity over time. Thus, the vaccination recommandations could evolve in the future to reach eradication in a medium or long term.

[Mumps virus: a comprehensive review]. / Le virus des oreillons.

Once very common in children, mumps virus infection is now much rarer thanks to vaccination, recommended in the majority of countries in the world. This virus of the family Paramyxoviridae has a marked tropism for glandular tissues which explains the great diversity of pathologies related to this virus, including parotitis, orchitis or meningitis. Due to the lower circulation of the virus, the proportion of infected adults increases. A surveillance system for mumps virus infections at the national and international levels is organized, particularly at the molecular level. In France, it is provided by the national reference center for Measles, Mumps and Rubella. Although it has led to a significant reduction in the number of cases, the long-term effectiveness of mumps vaccination is questionable. The nature of the vaccine strains and the lack of regular stimulation of populations by circulating wild viruses may explain, in part, the decrease in immunity over time. Thus, the vaccination recommandations could evolve in the future to reach eradication in a medium or long term.

Interlaboratory quality control of total HIV-1 DNA load measurement for multicenter reservoir studies.

BACKGROUND: Viral reservoirs represent an important barrier to HIV cure. Accurate markers of HIV reservoirs are needed to develop multicenter studies. The aim of this multicenter quality control (QC) was to evaluate the inter-laboratory reproducibility of total HIV-1-DNA quantification. METHODS: Ten laboratories of the ANRS-AC11 working group participated by quantifying HIV-DNA with a real-time qPCR assay (Biocentric) in four samples (QCMD). RESULTS: Good reproducibility was found between laboratories (standard deviation ≤ 0.2 log10 copies/106 PBMC) for the three positive QC that were correctly classified by each laboratory (QC1

SOFIA®RSV: prospective laboratory evaluation and implementation of a rapid diagnostic test in a pediatric emergency ward.

BACKGROUND: Respiratory syncytial virus (RSV) is responsible for severe respiratory infections and higher costs in medical care. The two aims of this work were to assess the performances of SOFIA®RSV tests in "real-life-laboratory" conditions (study 1) and implemented at point-of-care testing in a pediatric emergency department (ED, study 2), during two consecutive winter seasons. METHODS: In study 1, fresh nasopharyngeal swabs from patients of all ages were sampled in 1.5 ml of Universal virological Transport Medium (UTM) and prospectively tested using SOFIA®RSV tests. In study 2, conducted in a pediatric ED, nasopharyngeal swabs were placed in 3 ml of UTM. All SOFIA®RSV tests were confirmed by molecular testing, considered as reference method. The epidemiological and clinical features of tested patients, as well as the care of these patients after obtaining quick results were evaluated. RESULTS: The sensitivities of SOFIA®RSV in infants (aged under 24 months) performed in the laboratory and in the pediatric ED were respectively 95% (95% CI: 86.8-98.1) and 74.8% (95% CI: 68.0-80.9) compared to PCR. In study 1, the sensitivity among children (from 2 to 15 years old) and adults (above 15 years old) dropped to 45% (95% CI: 23.1-68.5) and 59% (95% CI: 32.9-81.6), respectively. In study 2, there were some differences in bed-management of SOFIA®RSV positive compared to SOFIA®RSV negative infants. CONCLUSIONS: SOFIA®RSV tests performed in the laboratory and in the pediatric ED show high and satisfactory sensitivities among young children under 24 months, which supports its robustness and reliability. However, the impact of these tests on patient care at point-of-care cannot be clearly assessed when considering the limits of the study 2 design.

Study and interest of cellular load in respiratory samples for the optimization of molecular virological diagnosis in clinical practice.

BACKGROUND: Respiratory viral diagnosis of upper respiratory tract infections has largely developed through multiplex molecular techniques. Although the sensitivity of different types of upper respiratory tract samples seems to be correlated to the number of sampled cells, this link remains largely unexplored. METHODS: Our study included 800 upper respiratory tract specimens of which 400 negative and 400 positive for viral detection in multiplex PCR. All samples were selected and matched for age in these 2 groups. For the positive group, samples were selected for the detected viral species. RESULTS: Among the factors influencing the cellularity were the type of sample (p < 0.0001); patient age (p < 0.001); viral positive or negative nature of the sample (p = 0.002); and, for the positive samples, the number of viral targets detected (0.004 < p < 0.049) and viral species. CONCLUSION: The cellular load of upper respiratory samples is multifactorial and occurs for many in the sensitivity of molecular detection. However it was not possible to determine a minimum cellularity threshold allowing molecular viral detection. The differences according to the type of virus remain to be studied on a larger scale.

What is the relevancy of a surveillance of mumps without a systematic laboratory confirmation in highly immunized populations? Epidemiology of suspected and biologically confirmed mumps cases seen in general practice in France between 2014 and 2020.

BACKGROUND: In France, mumps surveillance is conducted in primary care by the Sentinelles network, the National Reference Centre for Measles, Mumps and Rubella and Santé publique France. AIM: The objective of this study was to estimate the incidence of suspected mumps in general practice, the proportion of laboratory confirmed cases and the factors associated with a virological confirmation. METHODS: General practitioners (GPs) participating in the Sentinelles network should report all patients with suspected mumps according to a clinical definition in case of parotitis and a serological definition in case of clinical expression without parotitis. All suspected mumps cases reported between January 2014 and December 2020 were included. A sample of these cases were tested by real time reverse transcriptase polymerase chain reaction (RT-PCR) for mumps biological confirmation. RESULTS: A total of 252 individuals with suspected mumps were included in the study. The average annual incidence rate of suspected mumps in general practice in France between 2014 and 2020 was estimated at 11 cases per 100,000 population [CI95%: 6-17]. A mumps confirmation RT-PCR test was performed on 146 cases amongst which 17 (11.5 %) were positive. Age (between 20 and 29 years old), the presence of a clinical complication and an exposure to a suspected mumps case within the 21 days prior the current episode were associated with a mumps biological confirmation. CONCLUSION: If these results confirm the circulation of mumps virus in France, they highlight the limits of a surveillance without a systematic laboratory confirmation in highly immunized populations.

Severe acute respiratory syndrome coronavirus-2-related and imputable deaths in children: results from the French pediatric national registry.

BACKGROUND: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for an important mortality rate worldwide. We aimed to evaluate the actual imputability of SARS-CoV-2 on the mortality rate associated with SARS-CoV-2-related illnesses in the pediatric intensive care unit (PICU). Secondary objectives were to identify risk factors for death. METHODS: This national multicenter comparative study comprised all patients under 18 years old with positive SARS-CoV-2 polymerase chain reactions (PCRs) [acute corona virus disease 2019 (COVID-19) or incidental SARS-CoV-2 infection] and/or pediatric inflammatory multisystem syndrome (PIMS) recorded in the French PICU registry (PICURe) between September 1, 2021, and August 31, 2022. Included patients were classified and compared according to their living status at the end of their PICU stay. Deceased patients were evaluated by four experts in the field of pediatric infectiology and/or pediatric intensive care. The imputability of SARS-CoV-2 as the cause of death was classified into four categories: certain, very probable, possible, or unlikely, and was defined by any of the first three categories. RESULTS: There were 948 patients included of which 43 died (4.5%). From this, 26 deaths (67%) could be attributed to SARS-CoV-2 infection, with an overall mortality rate of 2.8%. The imputability of death to SARS-CoV-2 was considered certain in only one case (0.1%). Deceased patients suffered more often from comorbidities, especially heart disease, neurological disorders, hematological disease, cancer, and obesity. None of the deceased patients were admitted for pediatric inflammatory multisystem syndrome (PIMS). Mortality risk factors were male gender, cardiac comorbidities, cancer, and acute respiratory distress syndrome. CONCLUSIONS: SARS-CoV-2 mortality in the French pediatric population was low. Even though the imputability of SARS-CoV-2 on mortality was considered in almost two-thirds of cases, this imputability was considered certain in only one case.

Algorithm-based prediction of HIV-1 subtype D coreceptor use.

We compared the coreceptor tropism-predicting performance of a specific genotypic algorithm for HIV-1 subtype D and that of the geno2pheno algorithm with different cutoffs. The D-specific algorithm and geno2pheno with a false-positivity rate cutoff of 2.5% had the same concordance with the phenotypic determination. The geno2pheno algorithm with a false-positivity rate cutoff of 2.5%, more sensitive but slightly less specific, seems to be an appropriate alternative.