Abstract
We assessed the expression of CD169, a type I interferon-inducible receptor, on monocytes (monocyte CD169 mCD169) in 53 adult patients admitted to the hospital during the coronavirus disease ...2019 (COVID-19) outbreak for a suspicion of severe acute respiratory syndrome coronavirus 2 infection. Monocyte CD169 was strongly overexpressed in 30 of 32 (93.7%) confirmed COVID-19 cases, compared with 3 of 21 (14.3%) patients in whom the diagnosis of COVID-19 was finally ruled out. Monocyte CD169 was associated with the plasma interferon-alpha level and thrombocytopenia. Monocyte CD169 testing may be helpful for the rapid triage of suspected COVID-19 patients during an outbreak.
Blood collected and dried on a paper card - dried blood spot (DBS) - knows a growing interest as a sampling method that can be performed outside care facilities by capillary puncture, and transported ...in a simple and safe manner by mail. The benefits of this method for blood collection and transport has recently led the World Health Organization to recommend DBS for HIV and hepatitis B and C diagnosis. The clinical utility of DBS sampling to improve diagnostics and care of HIV and hepatitis B and C infection in hard to reach populations, key populations and people living in low-income settings was highlighted. Literature about usefulness of DBS specimens in the therapeutic cascade of care - screening, confirmation, quantification of nucleic acids, and resistance genotyping -, was reviewed. DBS samples are suitable for testing antibodies, antigens, or nucleic acids using most laboratory methods. Good sensibility and specificity have been reported for infant HIV diagnosis and diagnosis of hepatitis B and C. The performance of HIV RNA testing on DBS to identified virological failure on antiretroviral therapy is also high but not optimal because of the dilution of dried blood in the elution buffer, reducing the analytical sensitivity, and because of the contamination by intracellular HIV DNA. Standardized protocols are needed for inter-laboratory comparisons, and manufacturers should pursue regulatory approval for
diagnostics using DBS specimens. Despite these limitations, DBS sampling is a clinically relevant tool to improve access to infectious disease diagnosis worldwide.
Total HIV DNA is a standard marker to monitor the HIV reservoir in people living with HIV. We investigated HIV DNA quantification accuracy by a real-time PCR kit (qPCR) and digital PCR (dPCR) method ...within the same set of primers and probes. Among 48 aviremic patients followed for up to 7 years with qPCR, the mean coefficient of variation of total HIV DNA between two successive measurements was 77% (± 0.42log
HIVDNA copies/10
PBMC). The total HIV DNA quantified by the two PCR methods has a high correlation (0.99 and 0.83, for 8E5 and PLHIV samples, respectively), but we observed better repeatability and reproducibility of the dPCR compared to the qPCR (CV of 11.9% vs. 24.7% for qPCR, p-value = 0.024). Furthermore, we highlighted a decay of the number of HIV copies in the 8E5 cell line qPCR standard over time (from 0.73 to 0.43 copies per cell), contributing to variations of HIV DNA results in patients whose HIV reservoir should be theoretically stabilized. Our study highlighted that absolute quantification of total HIV DNA by dPCR allows more accurate monitoring of the HIV reservoir than qPCR in patients under prolonged antiretroviral therapy.
To estimate population-wide hepatitis B and C seroprevalence using dried blood spot samples acquired for human immunodeficiency virus (HIV) surveillance as part of the 2010-2011 Demographic and ...Health Survey in Burkina Faso.
We used the database acquired during the multistage, clustered, population-based survey, in which 15 377 participants completed questionnaires and provided dried blood spot samples for HIV testing. We extracted sociodemographic and geographic data including age, sex, ethnicity, education, wealth, marital status and region for each participant. We performed hepatitis B and C assays on 14 886 HIV-negative samples between March to October 2015, and calculated weighted percentages of hepatitis seroprevalence for each variable.
We estimated seroprevalence as 9.1% (95% confidence interval, CI: 8.5-9.7) for the hepatitis B surface antigen and 3.6% (95% CI: 3.3-3.8) for hepatitis C virus antibodies, classifying Burkina Faso as highly endemic for hepatitis B and low-intermediate for hepatitis C. The seroprevalence of hepatitis was higher in men than in women, and varied significantly for both with age, education, ethnicity and region. Extremely high HCV-Ab seroprevalence (13.2%; 95% CI: 10.6-15.7) was identified in the Sud-Ouest region, in particular within the youngest age group (15-20 years), indicating an ongoing epidemic.
Our population-representative hepatitis seroprevalence estimates in Burkina Faso advocate for the inclusion of hepatitis serological tests and risk factor questionnaire items in future surveys, the results of which are crucial for the development of appropriate health policies and infection control programmes.
Abstract
We explored antibody response after first and second BNT162b2 vaccinations, to predict the need for subsequent injections in nursing home (NH) residents. 369 NH residents were tested for IgG ...against SARS-CoV-2 Receptor-Binding Domain (RBD-IgG) and nucleoprotein-IgG (SARS-CoV-2 IgG II Quant and SARS-CoV-2 IgG Alinity assays, Abbott Diagnostics). In NH residents with prior SARS-CoV-2 infection, the first dose elicited high RBD-IgG levels (≥ 4160 AU/mL) in 99/129 cases (76.9%), with no additional antibody gain after the second dose in 74 cases (74.7%). However, a low RBD-IgG level (< 1050 AU/mL) was observed in 28 (21.7%) residents. The persistence of nucleoprotein-IgG and a longer interval between infection and the first dose were associated with a higher RBD-IgG response (p < 0.0001 and p = 0.0013, respectively). RBD-IgG below 50 AU/mL after the first dose predicted failure to reach the antibody concentration associated with a neutralizing effect after the second dose (≥ 1050 AU/mL). The BNT162b2 vaccine elicited a strong humoral response after the first dose in a majority of NH residents with prior SARS-CoV-2 infection. However, about one quarter of these residents require a second injection. Consideration should be given to immunological monitoring in NH residents to optimize the vaccine response in this vulnerable population.
Common representations of the world of gold mining-especially illegal-are usually negative: the activity conjures up images of drug trafficking, human exploitation, the sex trade, environmental ...destruction, and infectious diseases, in particular sexually transmitted infections (STIs). The aim of the present article is to describe the levels of risk behaviors such as transactional sex, multiple sexual partners, and the frequency of condom use, addictive substance consumption, and the prevalence of STIs among the population of illegal gold miners in French Guiana (FG), a French overseas entity in Amazonia, in order to guide potential interventions. An observational multicenter cross-sectional study was carried out from October to December 2019 along the two borders of FG with Suriname and Brazil at rest sites used by the miners. Among the 499 participants, transactional sex was very prevalent, declared by 33.5% of men and 8.4% of women. Condoms were more frequently used for transactional sex than with a non-commercial partner (93.4% versus 42.1%). More women were tested for HIV than men (91.1% versus 55.2%). Excessive alcohol consumption (57.3%%) and tobacco use (41.2%) were very frequent, but cocaine or crack consumption was low (1.2%), which refuted our initial assumption. Consumers of alcohol had more sexual partners and reported condom use more frequently. Prevalence of HIV, HCV, HBV, and syphilis was respectively 0.5% (95% CI: 0.1-2.1), 2.1% (95% CI: 0.7-3.6), 1.6% (95% CI: 0.3-2.8), and 12.4% (95% CI: 9.0-15.7), which was higher than in the local population, especially for syphilis. This study documents for the first time the risk behaviors of gold miners in FG. Although the level of condom use was high, the prevalence of STIs combined with the high rate of transactional sex should encourage an increase in prevention and screening, in particular through rapid tests, given the mobility of the population concerned.
We analyzed the results of the QuantiFERON Glod Plus assay (QFT) and cytokine patterns associated with active tuberculosis (ATB) among patients with positive QFT.
A total of 195 patients are ...QFT-positive, among which 24 had an ATB and 171 had a latent tuberculosis infection (LTBI). Interferon-gamma (IFN-γ) secretion was analyzed relative to interleukin-2 (IL-2), IFN-γ inducible protein or CXCL-10 (IP-10), and monokine induced by IFN-γ or CXCL-9 (MIG) secretion, and then compared between two sets of peptide antigens tube 1 - cluster of differentiation 4 (CD4
) T cell stimulation; tube 2 - CD4
/CD8
T cell response.
Higher IFN-γ responses were measured in the ATB group (
= 0.0089). The results showed that there was a lower ratio of tube 1/tube 2 IFN-γ concentrations in the ATB group (
= 0.0009), and a median interquartile ranges (IQR) difference between the two sets at -0.82 IU/ml (-1.67 to 0.18) vs. -0.07 IU/ml (-0.035 to 0.11,
< 0.0001) in the ATB group compared to the LTBI group, respectively. In addition, patients with low ratios of IL-2/IFN-γ, IP-10/IFN-γ, and MIG/IFN-γ were much more likely to have ATB.
High levels of IFN-γ secretion, preferential IFN-γ response in tube 2, and lower secretion of IL-2, IP-10, and MIG release relative to IFN-γ secretion were more likely observed in subjects with ATB. These features of T cell response may be helpful in low prevalence settings to suspect ATB in patients tested positive for IFN-γ release assays (IGRA).
The study was approved by the Montpellier University Hospital institutional review board (Institut de recherche en Biothérapie de Montpellier IRB-MTP_2020_06_202000534 and IRB-MTP ..._2021_04_202000534). ACKNOWLEDGMENTS The authors would like to thank (i) Anna Bedbrook for editorial assistance, (ii) Secours Infirmiers (Department of Geriatrics, Montpellier University Hospital), Catherine Vercruysse, Florence Biblocque (admission office, Montpellier University Hospital) for material support, and (iii) the residents and staff members of the nursing homes involved in the study. CONFLICT OF INTEREST STATEMENT Authors declare no conflicts of interest/Competing interests.
Interferon gamma (IFN-γ) release assays (IGRAs) detect Mycobacterium tuberculosis (Mtb) infection regardless of the active (ATB) or latent (LTBI) forms of tuberculosis (TB). In this study, ...Mtb-specific T cell response against region of deletion 1 (RD1) antigens were explored by a microbead multiplex assay performed in T-SPOT TB assay (T-SPOT) supernatants from 35 patients with ATB and 115 patients with LTBI. T-SPOT is positive when over 7 IFN-γ secreting cells (SC)/250 000 peripheral blood mononuclear cells (PBMC) are enumerated. However, over 100 IFN-γ SC /250 000 PBMC were more frequently observed in the ATB group compared to the LTBI group. By contrast, lower cytokine concentrations and lower cytokine productions relative to IFN-γ secretion were observed for IL 4, IL-12, TNF-α, GM-CSF, Eotaxin and IFN-α when compared to LTBI. Thus, high IFN-γ release and low cytokine secretions in relation with IFN-γ production appeared as signatures of ATB, corroborating that multicytokine Mtb-specific response against RD1 antigens reflects host capacity to contain TB reactivation. In this way, testing cytokine profile in IGRA supernatants would be helpful to improve ATB screening strategy including immunologic tests.
PDF
