Trans-vaccenic acid reprograms CD8+ T cells and anti-tumour immunity.

Diet-derived nutrients are inextricably linked to human physiology by providing energy and biosynthetic building blocks and by functioning as regulatory molecules. However, the mechanisms by which circulating nutrients in the human body influence specific physiological processes remain largely unknown. Here we use a blood nutrient compound library-based screening approach to demonstrate that dietary trans-vaccenic acid (TVA) directly promotes effector CD8+ T cell function and anti-tumour immunity in vivo. TVA is the predominant form of trans-fatty acids enriched in human milk, but the human body cannot produce TVA endogenously1. Circulating TVA in humans is mainly from ruminant-derived foods including beef, lamb and dairy products such as milk and butter2,3, but only around 19% or 12% of dietary TVA is converted to rumenic acid by humans or mice, respectively4,5. Mechanistically, TVA inactivates the cell-surface receptor GPR43, an immunomodulatory G protein-coupled receptor activated by its short-chain fatty acid ligands6-8. TVA thus antagonizes the short-chain fatty acid agonists of GPR43, leading to activation of the cAMP-PKA-CREB axis for enhanced CD8+ T cell function. These findings reveal that diet-derived TVA represents a mechanism for host-extrinsic reprogramming of CD8+ T cells as opposed to the intrahost gut microbiota-derived short-chain fatty acids. TVA thus has translational potential for the treatment of tumours.

How effective is the BNT162b2 mRNA vaccine against SARS-CoV-2 transmission and infection? A national programme analysis in Monaco, July 2021 to September 2022.

BACKGROUND: We quantified SARS-CoV-2 dynamics in different community settings and the direct and indirect effect of the BNT162b2 mRNA vaccine in Monaco for different variants of concern (VOC). METHODS: Between July 2021 and September 2022, we prospectively investigated 20,443 contacts from 6320 index cases using data from the Monaco COVID-19 Public Health Programme. We calculated secondary attack rates (SARs) in households (n = 13,877), schools (n = 2508) and occupational (n = 6499) settings. We used binomial regression with a complementary log-log link function to measure adjusted hazard ratios (aHR) and vaccine effectiveness (aVE) for index cases to infect contacts and contacts to be infected in households. RESULTS: In households, the SAR was 55% (95% CI 54-57) and 50% (48-51) among unvaccinated and vaccinated contacts, respectively. The SAR was 32% (28-36) and 12% (10-13) in workplaces, and 7% (6-9) and 6% (3-10) in schools, among unvaccinated and vaccinated contacts respectively. In household, the aHR was lower in contacts than in index cases (aHR 0.68 [0.55-0.83] and 0.93 [0.74-1.1] for delta; aHR 0.73 [0.66-0.81] and 0.89 [0.80-0.99] for omicron BA.1&2, respectively). Vaccination had no significant effect on either direct or indirect aVE for omicron BA.4&5. The direct aVE in contacts was 32% (17, 45) and 27% (19, 34), and for index cases the indirect aVE was 7% (- 17, 26) and 11% (1, 20) for delta and omicron BA.1&2, respectively. The greatest aVE was in contacts with a previous SARS-CoV-2 infection and a single vaccine dose during the omicron BA.1&2 period (45% [27, 59]), while the lowest were found in contacts with either three vaccine doses (aVE - 24% [- 63, 6]) or one single dose and a previous SARS-CoV-2 infection (aVE - 36% [- 198, 38]) during the omicron BA.4&5 period. CONCLUSIONS: Protection conferred by the BNT162b2 mRNA vaccine against transmission and infection was low for delta and omicron BA.1&2, regardless of the number of vaccine doses and previous SARS-CoV-2 infection. There was no significant vaccine effect for omicron BA.4&5. Health authorities carrying out vaccination campaigns should bear in mind that the current generation of COVID-19 vaccines may not represent an effective tool in protecting individuals from either transmitting or acquiring SARS-CoV-2 infection.

Biomarkers and cardiovascular outcomes in chimeric antigen receptor T-cell therapy recipients.

AIMS: Chimeric antigen receptor T-cell therapy (CAR-T) harnesses a patient's immune system to target cancer. There are sparse existing data characterizing death outcomes after CAR-T-related cardiotoxicity. This study examines the association between CAR-T-related severe cardiovascular events (SCE) and mortality. METHODS AND RESULTS: From a multi-centre registry of 202 patients receiving anti-CD19 CAR-T, covariates including standard baseline cardiovascular and cancer parameters and biomarkers were collected. Severe cardiovascular events were defined as a composite of heart failure, cardiogenic shock, or myocardial infarction. Thirty-three patients experienced SCE, and 108 patients died during a median follow-up of 297 (interquartile range 104-647) days. Those that did and did not die after CAR-T were similar in age, sex, and prior anthracycline use. Those who died had higher peak interleukin (IL)-6 and ferritin levels after CAR-T infusion, and those who experienced SCE had higher peak IL-6, C-reactive protein (CRP), ferritin, and troponin levels. The day-100 and 1-year Kaplan-Meier overall mortality estimates were 18% and 43%, respectively, while the non-relapse mortality (NRM) cumulative incidence rates were 3.5% and 6.7%, respectively. In a Cox model, SCE occurrence following CAR-T was independently associated with increased overall mortality risk [hazard ratio (HR) 2.8, 95% confidence interval (CI) 1.6-4.7] after adjusting for age, cancer type and burden, anthracycline use, cytokine release syndrome grade ≥ 2, pre-existing heart failure, hypertension, and African American ancestry; SCEs were independently associated with increased NRM (HR 3.5, 95% CI 1.4-8.8) after adjusting for cancer burden. CONCLUSION: Chimeric antigen receptor T-cell therapy recipients who experience SCE have higher overall mortality and NRM and higher peak levels of IL-6, CRP, ferritin, and troponin.

The Impact of Severe Acute Respiratory Syndrome Coronavirus 2 Vaccination and Infection on Neutralizing Antibodies: A Nation-wide Cross-sectional Analysis.

BACKGROUND: Neutralising antibodies (nAbs) play a critical role in the protection against severe COVID-19. In the era of vaccine boosters and repeated SARS-CoV-2 outbreaks, identifying individuals at risk represents a public health priority. METHODS: Relying on the Monaco COVID Public Health Programme, we evaluated nAbs from July 2021-June 2022 in 8,080 SARS-CoV-2 vaccinated and/or infected children and adults, at their inclusion visit. We stratified by infection status and investigated variables associated with nAbs using a generalised additive model. RESULTS: Infected and vaccinated participants had high and consistent nAbs (>800 IU/mL), which remained stable over time since injection, regardless of the number of vaccine doses, body mass index, sex, or age. By contrast, uninfected participants showed larger variability (two doses [V2] median 157.6; interquartile range [IQR] 43.3-439.1 IU/mL) versus three doses [V3] median 882.5; [829.5-914.8] IU/mL). NAbs decreased by 20% per month after V2 (adjusted ratio 0.80; 95%CI [0.79-0.82]), but remained stable after V3 (adjusted ratio 0.98; 95%CI [0.92-1.05]). CONCLUSIONS: Hybrid immunity provided stable, high and consistent nAbs over time. The benefit of boosters was marked to restore decaying nAbs in uninfected participants. NAbs could identify individuals at risk of severe COVID-19 and provide more targeted vaccine boosters' campaigns.

Community-level incidence and treatment seeking during febrile illness: Insights from health behaviour surveys in rural Thailand and Laos.

OBJECTIVE: Critical gaps remain in understanding community perceptions and treatment-seeking behaviours in case of fever. This is especially relevant considering global antimicrobial resistance, where fever is assumed to provoke non-judicious antibiotic use. Our study objective was therefore to document the community-level incidence of fever, the resulting treatment-seeking processes, and their underlying behavioural drivers. METHODS: In a cross-sectional observational design, we used descriptive and inferential statistics and multivariable regression analysis to estimate the population-level incidence of fever and individual and socio-economic factors associated with treatment-seeking process characteristics. We utilised a detailed publicly available survey of community-level treatment-seeking behaviour (collected in 2017/2018), comprising a representative sample of 2130 rural adults in Thailand (Chiang Rai Province) and Lao PDR (Salavan Province). RESULTS: Fever was reported by 7.1% of the rural adult population in Chiang Rai (95% CI: 5.1%-9.0%) and 7.5% in Salavan (95% CI: 4.5%-10.5%) during a 2-month recall period. Treatment-seeking patterns varied by socio-economic characteristics like precarious employment. 69.3% (95% CI: 60.8%-77.7%) of fever episodes involved access to formal (public/private) healthcare providers, 11.0% (95% CI: 4.5%-17.5%) involved informal providers, and 24.3% (95% CI: 16.6%-32.1%) took place without either formal or informal healthcare access. Febrile patients had on average 0.39 antibiotic use episodes when accessing formal healthcare settings, compared to 0.05 otherwise (p < 0.01). CONCLUSION: Treatment-seeking behaviour during fever varies according to population characteristics. Clinical studies would benefit from contextualising quantitative outcomes. Treatment algorithms for non-malarial febrile illnesses should involve outreach to informal healthcare and community settings to support patients in precarious circumstances, and antibiotic resistance interventions should prioritise formal healthcare facilities.

Fever and health-seeking behaviour among migrants living along the Thai-Myanmar border: a mixed-methods study.

BACKGROUND: Fever is a common reason to seek healthcare in Southeast Asia, and the decline of malaria has complexified how is perceived, and what actions are taken towards it. We investigated the concept of fever and the determinants influencing health-seeking behaviours among migrants on the Thai-Myanmar border, where rapid economic development collides with precarious political and socio-economic conditions. METHODS: We implemented a mixed-methods study between August to December 2019. Phase I used a qualitative approach, with in-depth interviews and focus group discussions. Phase II used a quantitative approach with a close-ended questionnaire based on Phase I findings. A conditional inference tree (CIT) model first identified geographic and socio-demographic determinants, which were then tested using a logistic regression model. RESULTS: Fever corresponded to a high diversity of conceptions, symptoms and believed causes. Self-medication was the commonest behaviour at fever onset. If fever persisted, migrants primarily sought care in humanitarian cost-free clinics (45.5%, 92/202), followed by private clinics (43.1%, 87/202), health posts (36.1%, 73/202), public hospitals (33.7%, 68/202) and primary care units (30, 14.9%). The qualitative analysis identified distance and legal status as key barriers for accessing health care. The quantitative analysis further investigated determinants influencing health-seeking behaviour: living near a town where a cost-free clinic operated was inversely associated with seeking care at health posts (adjusted odds ratio [aOR], 0.40, 95% confidence interval [95% CI] [0.19-0.86]), and public hospital attendance (aOR 0.31, 95% CI [0.14-0.67]). Living further away from the nearest town was associated with health posts attendance (aOR 1.05, 95% CI [1.00-1.10] per 1 km). Having legal status was inversely associated with cost-free clinics attendance (aOR 0.27, 95% CI [0.10-0.71]), and positively associated with private clinic and public hospital attendance (aOR 2.56, 95% CI [1.00-6.54] and 5.15, 95% CI [1.80-14.71], respectively). CONCLUSIONS: Fever conception and believed causes are context-specific and should be investigated prior to any intervention. Distance to care and legal status were key determinants influencing health-seeking behaviour. Current economic upheavals are accelerating the unregulated flow of undocumented migrants from Myanmar to Thailand, warranting further inclusiveness and investments in the public health system.

Sensitivity of C-reactive protein for the identification of patients with laboratory-confirmed bacterial infections in northern Tanzania.

OBJECTIVE: Identifying febrile patients requiring antibacterial treatment is challenging, particularly in low-resource settings. In South-East Asia, C-reactive protein (CRP) has been demonstrated to be highly sensitive and moderately specific in detecting bacterial infections and to safely reduce unnecessary antibacterial prescriptions in primary care. As evidence is scant in sub-Saharan Africa, we assessed the sensitivity of CRP in identifying serious bacterial infections in Tanzania. METHODS: Samples were obtained from inpatients and outpatients in a prospective febrile illness study at two hospitals in Moshi, Tanzania, 2011-2014. Bacterial bloodstream infections (BSI) were established by blood culture, and bacterial zoonotic infections were defined by ≥4 fold rise in antibody titre between acute and convalescent sera. The sensitivity of CRP in identifying bacterial infections was estimated using thresholds of 10, 20 and 40 mg/l. Specificity was not assessed because determining false-positive CRP results was limited by the lack of diagnostic testing to confirm non-bacterial aetiologies and because ascertaining true-negative cases was limited by the imperfect sensitivity of the diagnostic tests used to identify bacterial infections. RESULTS: Among 235 febrile outpatients and 569 febrile inpatients evaluated, 31 (3.9%) had a bacterial BSI and 61 (7.6%) had a bacterial zoonosis. Median (interquartile range) CRP values were 173 (80-315) mg/l in bacterial BSI, and 108 (31-208) mg/l in bacterial zoonoses. The sensitivity (95% confidence intervals) of CRP was 97% (83%-99%), 94% (79%-98%) and 90% (74%-97%) for identifying bacterial BSI, and 87% (76%-93%), 82% (71%-90%) and 72% (60%-82%) for bacterial zoonoses, using thresholds of 10, 20 and 40 mg/l, respectively. CONCLUSION: C-reactive protein was moderately sensitive for bacterial zoonoses and highly sensitive for identifying BSIs. Based on these results, operational studies are warranted to assess the safety and clinical utility of CRP for the management of non-malaria febrile illness at first-level health facilities in sub-Saharan Africa.

OBJECTIF: Identifier les patients fébriles nécessitant un traitement antibactérien est un défi, en particulier dans les milieux à faibles ressources. En Asie du Sud-Est, il a été démontré que la protéine C-réactive (CRP) est très sensible et modérément spécifique dans la détection des infections bactériennes et qu'elle réduit en toute sécurité les prescriptions antibactériennes inutiles dans les soins primaires. Comme les données sont rares en Afrique subsaharienne (ASS), nous avons évalué la sensibilité de la CRP dans l'identification des infections bactériennes sévères en Tanzanie. MÉTHODES: Des échantillons ont été obtenus auprès de patients hospitalisés et ambulatoires dans une étude prospective sur les maladies fébriles dans deux hôpitaux à Moshi, en Tanzanie de 2011 à 2014. Les infections bactériennes du sang (IBS) ont été identifiées par la culture du sang et les infections bactériennes zoonotiques ont été définies par une élevation ≥ 4 fois le titre des anticorps entre les sérums en aiguë et en convalescence. La sensibilité de la CRP dans l'identification des infections bactériennes a été estimée en utilisant des seuils de 10, 20 et 40 mg/L. La spécificité n'a pas été évaluée parce que la détermination des résultats faux positifs de la CRP était limitée par le manque de tests de diagnostic pour confirmer les étiologies non bactériennes et parce que la confirmation des vrais cas négatifs était limitée par la sensibilité imparfaite des tests de diagnostic utilisés pour identifier les infections bactériennes. RÉSULTATS: Sur 235 patients ambulatoires fébriles et 569 patients hospitalisés fébriles évalués, 31 (3.9%) avaient une IBS et 61 (7.6%) avaient une zoonose bactérienne. Les valeurs médianes (intervalle interquartile) de la CRP étaient de 173 (80-315) mg/L dans les IBS et de 108 (31-208) mg/L dans les zoonoses bactériennes. La sensibilité (intervalles de confiance à 95%) de la CRP était de 97% (83-99%), 94% (79-98%), 90% (74-97%) pour identifier les IBS et 87% (76-93% ), 82% (71-90%), 72% (60-82%) pour les zoonoses bactériennes, en utilisant des seuils de 10, 20 et 40 mg/L respectivement. CONCLUSION: La CRP était modérément sensible pour les zoonoses bactériennes et hautement sensible pour l'identification des IBS. Sur la base de ces résultats, des études opérationnelles sont justifiées pour évaluer la sécurité et l'utilité clinique de la CRP pour la prise en charge des maladies fébriles non paludiques dans les établissements de santé de premier niveau en ASS.

Accuracy of commercially available c-reactive protein rapid tests in the context of undifferentiated fevers in rural Laos.

BACKGROUND: C-Reactive Protein (CRP) has been shown to be an accurate biomarker for discriminating bacterial from viral infections in febrile patients in Southeast Asia. Here we investigate the accuracy of existing rapid qualitative and semi-quantitative tests as compared with a quantitative reference test to assess their potential for use in remote tropical settings. METHODS: Blood samples were obtained from consecutive patients recruited to a prospective fever study at three sites in rural Laos. At each site, one of three rapid qualitative or semi-quantitative tests was performed, as well as a corresponding quantitative NycoCard Reader II as a reference test. We estimate the sensitivity and specificity of the three tests against a threshold of 10 mg/L and kappa values for the agreement of the two semi-quantitative tests with the results of the reference test. RESULTS: All three tests showed high sensitivity, specificity and kappa values as compared with the NycoCard Reader II. With a threshold of 10 mg/L the sensitivity of the tests ranged from 87-98 % and the specificity from 91-98 %. The weighted kappa values for the semi-quantitative tests were 0.7 and 0.8. CONCLUSION: The use of CRP rapid tests could offer an inexpensive and effective approach to improve the targeting of antibiotics in remote settings where health facilities are basic and laboratories are absent. This study demonstrates that accurate CRP rapid tests are commercially available; evaluations of their clinical impact and cost-effectiveness at point of care is warranted.

Performance of C-reactive protein and procalcitonin to distinguish viral from bacterial and malarial causes of fever in Southeast Asia.

BACKGROUND: Poor targeting of antimicrobial drugs contributes to the millions of deaths each year from malaria, pneumonia, and other tropical infectious diseases. While malaria rapid diagnostic tests have improved use of antimalarial drugs, there are no similar tests to guide the use of antibiotics in undifferentiated fevers. In this study we estimate the diagnostic accuracy of two well established biomarkers of bacterial infection, procalcitonin and C-reactive protein (CRP) in discriminating between common viral and bacterial infections in malaria endemic settings of Southeast Asia. METHODS: Serum procalcitonin and CRP levels were measured in stored serum samples from febrile patients enrolled in three prospective studies conducted in Cambodia, Laos and, Thailand. Of the 1372 patients with a microbiologically confirmed diagnosis, 1105 had a single viral, bacterial or malarial infection. Procalcitonin and CRP levels were compared amongst these aetiological groups and their sensitivity and specificity in distinguishing bacterial infections and bacteraemias from viral infections were estimated using standard thresholds. RESULTS: Serum concentrations of both biomarkers were significantly higher in bacterial infections and malaria than in viral infections. The AUROC for CRP in discriminating between bacterial and viral infections was 0.83 (0.81-0.86) compared with 0.74 (0.71-0.77) for procalcitonin (p < 0.0001). This relative advantage was evident in all sites and when stratifying patients by age and admission status. For CRP at a threshold of 10 mg/L, the sensitivity of detecting bacterial infections was 95% with a specificity of 49%. At a threshold of 20 mg/L sensitivity was 86% with a specificity of 67%. For procalcitonin at a low threshold of 0.1 ng/mL the sensitivity was 90% with a specificity of 39%. At a higher threshold of 0.5 ng/ul sensitivity was 60% with a specificity of 76%. CONCLUSION: In samples from febrile patients with mono-infections from rural settings in Southeast Asia, CRP was a highly sensitive and moderately specific biomarker for discriminating between viral and bacterial infections. Use of a CRP rapid test in peripheral health settings could potentially be a simple and affordable measure to better identify patients in need of antibacterial treatment and part of a global strategy to combat the emergence of antibiotic resistance.

Fertility treatments, congenital malformations, fetal loss, and childhood acute leukemia: the ESCALE study (SFCE).

BACKGROUND: This study investigated the relationships between childhood acute leukemia (AL) and selective maternal and birth characteristics, including congenital malformations and the use of fertility treatment, for which the literature remains scarce. PROCEDURE: The national registry-based case-control study ESCALE was carried out in France in 2003-2004. Population controls were frequency matched with cases on age and gender. Data were obtained from structured telephone questionnaires. Odds ratios (OR) and their 95% confidence intervals were estimated using unconditional regression models adjusted for potential confounders. RESULTS: In all, 764 cases of AL (648 lymphoblastic AL (acute lymphoblastic leukemia, ALL) and 101 myeloblastic AL) and 1,681 controls were included. The AL cases' mothers reported congenital malformations more frequently than the controls' mothers (OR = 1.5 [1.0-2.4]). ALL was significantly associated with the use of fertility treatment for the index pregnancy (OR = 1.9 [1.3-2.8]). In particular, ALL was associated with ovulation induction only (OR = 2.6 [1.6-4.3]), but not with in vitro fertilization (IVF, OR = 1.0 [0.4-2.3]) or artificial insemination (OR = 1.3 [0.5-3.9]). A positive association was also observed for the difficulty of becoming pregnant without fertility treatment (OR = 1.5 [1.0-2.1]). AL was positively associated with a history of voluntary abortion (OR = 1.4 [1.1-1.8]) but not with a history of spontaneous (OR = 0.8 [0.7-1.0]) or therapeutic (OR = 0.7 [0.5-1.1]) abortion. CONCLUSION: The results suggest that subfertility in itself and ovulation induction may be associated with ALL, and support a positive association with congenital malformations. The links with the various types of fertility drugs and the underlying causes of infertility need to be investigated further.

The impact of C-reactive protein testing on treatment-seeking behavior and patients' attitudes toward their care in Myanmar and Thailand.

C-reactive protein (CRP) point-of-care testing can reduce antibiotic prescribing in primary care patients with febrile and respiratory illness, yet little is known about its effects on treatment-seeking behavior. If patients go on to source antibiotics elsewhere, the impact of CRP testing will be limited. A randomized controlled trial assessed the impact of CRP testing on antibiotic prescriptions in Myanmar and Thai primary care patients with a febrile illness. Here we report patients' treatment-seeking behavior before and during the two-week study period. Self-reported antibiotic use is compared against urine antibacterial activity. Patients' opinions towards CRP testing were evaluated. Antibiotic use before study enrolment was reported by 5.4% while antimicrobial activity was detected in 20.8% of samples tested. During the study period, 14.8% of the patients sought additional healthcare, and 4.3% sourced their own antibiotics. Neither were affected by CRP testing. Overall, patients' satisfaction with their care and CRP testing was high. CRP testing did not affect patients' treatment-seeking behavior during the study period whilst modestly reducing antibiotic prescriptions. CRP testing appears to be acceptable to patients and their caregivers.

Distinctive serotypes of SARS-related coronaviruses defined by convalescent sera from unvaccinated individuals.

Multiple Omicron sub-lineages have emerged, with Omicron XBB and XBB.1.5 subvariants becoming the dominant variants globally at the time of this study. The key feature of new variants is their ability to escape humoral immunity despite the fact that there are limited genetic changes from their preceding variants. This raises the question of whether Omicron should be regarded as a separate serotype from viruses serologically clustered with the ancestral severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Here, we present cross-neutralization data based on a pseudovirus neutralization test using convalescent sera from naïve individuals who had recovered from primary infection by SARS-CoV-1 and SARS-CoV-2 strains/variants including the ancestral virus and variants Beta, Delta, Omicron BA.1, Omicron BA.2 and Omicron BA.5. The results revealed no significant cross-neutralization in any of the three-way testing for SARS-CoV-1, ancestral SARS-CoV-2 and SARS-CoV-2 Omicron subvariants. The data argue for the assignment of three distinct serotypes for the currently known human-infecting SARS-related coronaviruses.

First Detection of the SARS-CoV-2 Omicron BA.5/22B in Monaco.

The Omicron BA.5/22B variant has been designated as a "variant of concern" by the World Health Organization. We describe, here, the first evidence in Monaco of infection with an Omicron BA.5/22B variant, probably imported from the Republic of Seychelles, harboring a rare combination of non-BA.5/22B signature amino acid changes. SARS-CoV-2 neutralizing antibodies were measured with a surrogate virus neutralization test. SARS-CoV-2 genotype screening was performed on nasopharyngeal samples with a multiplex qPCR assay. The SARS-CoV-2 genome was obtained by next-generation sequencing with the Illumina COVID-seq protocol, then assembly using bioinformatics pipelines and software was performed. The BA.5/22B spike protein structure was obtained by molecular modeling. Two spouses were SARS-CoV-2-diagnosed the day they returned from a one-week trip in the Republic of Seychelles. SARS-CoV-2 qPCR screening for variant-specific mutations identified an Omicron variant BA.1/21K, BA.4/22A, or BA.5/22B. A SARS-Co-2 BA.5/22B variant genome was recovered from one of the spouses. Aside from BA.5/22B-defining amino acid substitutions, four other amino acid changes were encoded including Q556K in ORF1a, K2557R in ORF1b, and A67V and A829T in spike; only 13 genomes in sequence databases harbored these four mutations concurrently. Structural analysis of this BA.5/22B variant predicted that A829T in spike may result in a compaction that may affect conformational plasticity. Overall, our findings warrant performing genome-based genotypic surveillance to survey accurately the emergence and circulation of SARS-CoV-2 variants worldwide and point out that their first occurrence in a country is often through international travel despite implemented countermeasures.

Associations between maternal obesity and infectious morbidity in Zimbabwean infants.

The prevalence of overweight and obesity is increasing among reproductive-age women in sub-Saharan Africa. Whether maternal body mass index (BMI) influences the risk of infant infections in low- and middle-income countries (LMIC) is uncertain. We used data from a birth cohort of 5344 HIV-unexposed Zimbabwean infants with available data on maternal BMI, to calculate rates of sick clinic visits for infections during the first 12 months postpartum, and adjusted hazard ratios (aHR) for each maternal BMI group. Compared to infants of mothers with normal BMI, the rate of sick clinic visits for any infection progressively rose among infants of overweight (aHR 1.05; 95%CI 0.99, 1.11) and obese women (aHR 1.15; 95%CI 1.05, 1.25). Excess clinic attendances were particularly due to skin, respiratory and ear infections. Maternal obesity may therefore influence infant infectious morbidity in LMIC over the first year after birth.

Evaluation of the Panbio Leptospira IgM ELISA among Outpatients Attending Primary Care in Southeast Asia.

Despite estimates suggesting Leptospira spp. being endemic in Southeast Asia, evidence remains limited. Diagnostic accuracy evaluations based on Leptospira ELISA mainly rely on hospitalized and severe patients; therefore, studies measuring the pathogen burden may be inaccurate in the community. We evaluated the Panbio Leptospira ELISA IgM among 656 febrile outpatients attending primary care in Chiangrai, Thailand, and Hlaing Tha Yar, Yangon, Myanmar. ELISA demonstrated limited diagnostic accuracy for the detection of acute leptospiral infection using the manufacturer recommended cutoff, with a sensitivity of 71.4% and specificity of 36.4%, and an area under the receiver operator characteristic curve value of 0.65 (95% CI: 0.41-0.89), compared with our reference test, the PCR assay. ELISA also performed poorly as a screening tool for detecting recent exposure to Leptospira spp. compared with the "gold-standard" microscopic agglutination test, with a specificity of 42.7%. We conclude that the utility of the Leptospira IgM ELISA for both serodiagnosis and seroprevalence is limited in our setting.

Value of C-reactive protein in differentiating viral from bacterial aetiologies in patients with non-malaria acute undifferentiated fever in tropical areas: a meta-analysis and individual patient data study.

C-reactive protein (CRP) is used to discriminate common bacterial and viral infections, but its utility in tropical settings remains unknown. We performed a meta-analysis of studies performed in Asia and Africa. First, mean CRP levels for specific tropical infections were calculated. Thereafter, individual patient data (IPD) from patients with non-malarial undifferentiated fever (NMUF) who were tested for viral and bacterial pathogens were analysed, calculating separate cut-off values and their performance in classifying viral or bacterial disease. Mean CRP levels of 7307 patients from 13 countries were dengue 12.0 mg/l (standard error [SE] 2.7), chikungunya 41.0 mg/l (SE 19.5), influenza 15.9 mg/l (SE 6.3), Crimean-Congo haemorrhagic fever 9.7 mg/l (SE 4.7), Salmonella 61.9 mg/l (SE 5.4), Rickettsia 61.3 mg/l (SE 8.8), Coxiella burnetii 98.7 mg/l (SE 44.0) and Leptospira infections 113.8 mg/l (SE 23.1). IPD analysis of 1059 NMUF patients ≥5 y of age showed CRP <10 mg/l had 52% sensitivity (95% confidence interval [CI] 48 to 56) and 95% specificity (95% CI 93 to 97) to detect viral infections. CRP >40 mg/l had 74% sensitivity (95% CI 70 to 77) and 84% specificity (95% CI 81 to 87) to identify bacterial infections. Compared with routine care, the relative risk for incorrect classification was 0.64 (95% CI 0.55 to 0.75) and the number needed to test for one extra correctly classified case was 8 (95% CI 6 to 12). A two cut-off value CRP test may help clinicians to discriminate viral and bacterial aetiologies of NMUF in tropical areas.

Inter-prescriber variability in the decision to prescribe antibiotics to febrile patients attending primary care in Myanmar.

BACKGROUND: Most antibiotic prescribing occurs in primary care. Even within the same health facility, there may be differences between prescribers in their tendency to prescribe antibiotics, which may be masked by summary data. We aimed to quantify prescriber variability in antibiotic prescription to patients with acute fever in primary care clinics in Myanmar. METHODS: We conducted a secondary analysis of prescribing data from 1090 patient consultations with 40 prescribing doctors from a trial investigating the effect of point-of-care C-reactive protein (CRP) tests on antibiotic prescription for acute fever. We used multilevel logistic regression models to assess inter-prescriber variability in the decision to prescribe antibiotics. RESULTS: The median odds ratio (MOR) in the unadjusted model was 1.82 (95% CI: 1.47-2.56) indicating that when two prescribers from this population are randomly selected then in half of these pairs the odds of prescription will be greater than 1.82-fold higher in one prescriber than the other. The estimated variability from this sample of prescribers corresponds to a population of prescribers where the top 25% of prescribers will prescribe antibiotics to over 41% of patients while the bottom 25% will prescribe antibiotics to less than 23% of patients. Inter-prescriber variation in antibiotic prescribing remained after adjustment for patient characteristics and CRP information (P < 0.001). CONCLUSIONS: Despite sharing the same management guidelines, there was substantial inter-prescriber variation in antibiotic prescription to patients with acute fever. This variation should be considered when designing trials and stewardship programmes aiming to reduce inappropriate antibiotic prescribing.

Precarity and clinical determinants of healthcare-seeking behaviour and antibiotic use in rural Laos and Thailand.

BACKGROUND: The social determinants of health are a decisive yet persistently understudied area for tackling global health challenges like antimicrobial resistance (AMR). Precarity is one determinant whose importance is increasingly recognised, which we define here as 'a form of pernicious self-dependence that undermines individuals' control over their own lives and limits their ability to flexibly respond to crises'. We aimed to assess the relationship between precarity, other forms of deprivation and healthcare-seeking behaviour by asking, 'What is the impact of precarity, marginalisation and clinical presentation on healthcare-seeking behaviour?' and 'Do patients experiencing precarious livelihoods have clinically less advisable healthcare-seeking behaviour?' METHODS: We used healthcare-seeking behaviour census survey data from rural Thailand and Laos, wherein five rural communities were surveyed two times over a period of 3 months (2-month recall period). Using descriptive statistical and multivariate logistic regression analysis on the illness level, we studied precarity alongside clinical presentation, marginalisation and facilitating solutions during an illness (eg, health-related phone use) as determinants of healthcare-seeking behaviour in the form of healthcare access and antibiotic use. RESULTS: The data included 1421 illness episodes from 2066 villagers. Patients in precarious circumstances were up to 44.9 percentage points more likely to misuse antibiotics in the presence of situational facilitators (predicted antibiotic misuse: 6.2% (95% CI: 0.9% to 11.4%) vs 51.1% (95% CI: 16.6% to 85.5%) for precarious circumstances with/without facilitation). Marginalisation was linked to lower antibiotic use, but this did not translate into clinically more advisable behaviour. Clinical presentation played only a minor role in determining healthcare access and antibiotic use. CONCLUSIONS: This study underlines the importance of context and local livelihoods in tackling drug resistance. While supporting the growing emphasis on AMR-sensitive development policy, we call for future research to study systematically the healthcare-seeking behaviour impact of precarious livelihoods, social policy and community development initiatives. TRIAL REGISTRATION NUMBER: NCT03241316.