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Streptococcus pneumoniae is the main bacterial pathogen causing respiratory infections. Since the COVID-19 pandemic emerged, less pneumococcal disease was identified by surveillance systems around the world. Measures to prevent transmission of SARS-CoV-2 also reduce transmission of pneumococci, but this would gradually lead to lower disease rates. Here, we explore additional factors that have contributed to the instant drop in pneumococcal disease cases captured in surveillance. Our observations on referral practices and other impediments to diagnostic testing indicate that residual IPD has likely occurred but remained undetected by conventional hospital-based surveillance. Depending on setting, we discuss alternative monitoring strategies that could improve sight on pneumococcal disease dynamics.

IntroductionPatients with clinical malaria have an increased risk for bacterial bloodstream infections. We hypothesized that asymptomatic malaria parasitemia increases susceptibility for bacterial infections through an effect on the innate immune system. We measured circulating cytokine levels and ex-vivo cytokine production capacity in asymptomatic malaria and compared with controls.MethodsData were collected from asymptomatic participants ex-vivo stimulated with S. aureus, E. coli LPS and Salmonella Typhimurium; cytokine concentrations (TNF-α, IFN-γ, IL-1β, IL-6, IL-10) were measured on supernatants using ELISA.ResultsIncluded were children with clinical malaria (n=118), bacteremia (n=22), malaria and bacteremia co-infection (n=9), asymptomatic malaria (n=125), and asymptomatic controls (n=237). Children with either clinical or asymptomatic malaria had higher plasma cytokine concentrations than controls. Cytokine concentrations correlated positively with malaria parasite density with the strongest correlation for IL-10 in both asymptomatic (r=0.63) and clinical malaria (r=0.53). Patients with bacteremia had lower circulating IL-10, TNF-α and IFN-γ and higher IL-6 concentrations, compared to clinical malaria. Ex-vivo whole blood cytokine production to LPS and S. aureus was significantly lower in asymptomatic malaria compared to controls. Whole blood IFN-γ and IL-10 production in response to Salmonella was also lower in asymptomatic malaria.InterpretationIn children with asymptomatic malaria, cytokine responses upon ex-vivo bacterial stimulation are downregulated. Further studies are needed to explore if the suggested impaired innate immune response to bacterial pathogens also translates into impaired control of pathogens such as Salmonella spp.

Background New hemocytometric parameters can be used to differentiate causes of acute febrile illness (AFI). We evaluated a software algorithm–Infection Manager System (IMS)—which uses hemocytometric data generated by Sysmex hematology analyzers, for its accuracy to detect bacteremia in AFI patients with and without malaria in Burkina Faso. Secondary aims included comparing the accuracy of IMS with C-reactive protein (CRP) and procalcitonin (PCT). Methods In a prospective observational study, patients of ≥ three-month-old (range 3 months– 90 years) presenting with AFI were enrolled. IMS, blood culture and malaria diagnostics were done upon inclusion and additional diagnostics on clinical indication. CRP, PCT, viral multiplex PCR on nasopharyngeal swabs and bacterial- and malaria PCR were batch-tested retrospectively. Diagnostic classification was done retrospectively using all available data except IMS, CRP and PCT results. Findings A diagnosis was affirmed in 549/914 (60.1%) patients and included malaria (n = 191) bacteremia (n = 69), viral infections (n = 145), and malaria-bacteremia co-infections (n = 47). The overall sensitivity, specificity, and negative predictive value (NPV) of IMS for detection of bacteremia in patients of ≥ 5 years were 97.0% (95% CI: 89.8–99.6), 68.2% (95% CI: 55.6–79.1) and 95.7% (95% CI: 85.5–99.5) respectively, compared to 93.9% (95% CI: 85.2–98.3), 39.4% (95% CI: 27.6–52.2), and 86.7% (95% CI: 69.3–96.2) for CRP at ≥20mg/L. The sensitivity, specificity and NPV of PCT at 0.5 ng/ml were lower at respectively 72.7% (95% CI: 60.4–83.0), 50.0% (95% CI: 37.4–62.6) and 64.7% (95% CI: 50.1–77.6) The diagnostic accuracy of IMS was lower among malaria cases and patients, Author summary This study describes the diagnostic accuracy of the Infection Manager System (IMS), a novel diagnostic algorithm for febrile illnesses that is equipped on a routine hematology analyzer. The latest generation hematology analyzers allow better differentiation between leukocyte subsets and their phenotype. The IMS was created, using differences in immune cell subsets (their activation status for instance), to differentiate viral from bacterial etiologies of fever. Such a tool may guide clinicians in their decision the initiate or withhold antimicrobial therapy. The study was carried out among febrile patients aged 3 months and older in rural Burkina Faso, a sub-Saharan African setting where malaria is endemic. Standard microbiological techniques such as blood culture were used as a reference to assess the diagnostic accuracy of IMS. We then compared the diagnostic accuracy of the IMS with the marketed biomarkers C-reactive protein (CRP) and procalcitonin (PCT). Our study showed that the diagnostic performance of the IMS was similar to CRP and better than PCT to detect bacteremia in patients with and without malaria co-infection. Further studies are needed to see if the IMS can be safely used to guide initial antimicrobial treatment and help to reduce further spread of antimicrobial resistance.

BackgroundIn low- and middle-income countries (LMIC), the prevalence of antimicrobial resistance (AMR) is increasing. WHO recommends monitoring antibiotic use, in particular Watch antibiotics, clinical important but at risk of becoming ineffective due to increasing AMR. We investigated antibiotic use at primary care or community-level in rural Burkina Faso.MethodsDuring 2016-2017, patients aged >3 months admitted with severe acute fever to the rural hospital of Nanoro Health District, Burkina Faso, reported antibiotic use in the two weeks prior to consultation or hospitalization, which we analysed using the WHO Access, Watch, Reserve (AWaRe) classification. Most Watch antibiotics, e.g. ceftriaxone, are not recommended at primary health center level, as is also the case for ciprofloxacin in children.ResultsOf 920 participants (63.0% ≤14 years), pre-admission antibiotic use was reported by 363 (39.5%) of whom 58 (16.0%) reported more than one antibiotic. Use was more frequent among health center referrals (231, 54.0%) than among self-referred patients (131, 26.7%, p14 year olds (72, 51.1%) than 0-14 year olds (87, 30.7%) and among referrals (41, 28.1%) compared to self-referred patients (117, 42.2%). Most frequently used Watch antibiotics were ceftriaxone (114, 26.9%) and ciprofloxacin (32, 7.5%). Among antibiotics reported by referral patients, ceftriaxone and ciprofloxacin were respectively recorded 100 (36.1%) and 12 times (4.3%).ConclusionThe frequent use of Watch group antibiotics prior to presentation to the hospital in rural Burkina Faso highlights the need to address primary care, over-the-counter and informal community-level antibiotic use as part of antibiotic stewardship in LMIC, facilitating referral, access to qualified prescribers, or improving diagnostic tools in health centers.

OBJECTIVES: Areas with declining malaria transmission in sub-Saharan Africa have recently witnessed important changes in the aetiology of childhood acute febrile illness (AFI). We describe the aetiology of AFI in a high malaria transmission area in rural Burkina Faso. METHODS: In a prospective hospital-based diagnostic study, children aged 3 months to 15 years with AFI were recruited and assessed using a systematic diagnostic protocol, including blood cultures, whole blood PCR on a selection of bacterial pathogens, malaria diagnostics and a multiplex PCR on nasopharyngeal swabs targeting 21 viral and 4 bacterial respiratory pathogens. RESULTS: A total of 589 children with AFI were enrolled from whom an infectious disease was considered in 575 cases. Acute respiratory tract infections, malaria and invasive bacterial infections (IBI) accounted for 179 (31.1%), 175 (30.4%) and 75 (13%) of AFI cases respectively; 16 (21.3%) of IBI cases also had malarial parasitaemia. A viral pathogen was demonstrated from the nasopharynx in 157 children (90.7%) with respiratory tract symptoms. Of all children with viral respiratory tract infections, 154 (92.4% received antibiotics, whereas no antibiotic was provided in 13 (17%) of IBI cases. CONCLUSIONS: Viral respiratory infections are a common cause of childhood AFI in high malaria transmission areas, next to malaria and IBI. These findings highlight the importance of interventions to improve targeted treatment with antimicrobials. Most patients with viral infections received antibiotics unnecessarily, while a considerable number with IBI did not receive antibiotics. ispartof: CLINICAL MICROBIOLOGY AND INFECTION vol:27 issue:4 pages:590-596 ispartof: location:England status: published

Asymptomatic malaria infections may affect red blood cell (RBC) homeostasis. Reports indicate a role for chronic hemolysis and splenomegaly, however, the underlying processes are incompletely understood. New hematology analysers provide parameters for a more comprehensive analysis of RBC hemostasis. Complete blood counts were analysed in subjects from all age groups (n = 1118) living in a malaria hyperendemic area and cytokines and iron biomarkers were also measured. Subjects were divided into age groups ( Trial registration: Prospective diagnostic study: ClinicalTrials.gov identifier: NCT02669823. Explorative cross-sectional field study: ClinicalTrials.gov identifier: NCT03176719.

Background Salmonella Typhimurium and Enteritidis are major causes of bloodstream infection in children in sub-Saharan Africa. This study assessed evidence for their zoonotic versus human reservoir. Methods Index patients were children with blood culture confirmed Salmonella infection recruited during a microbiological surveillance study in Nanoro, rural Burkina between May 2013 and August 2014. After consent, their households were visited. Stool from household members and livestock (pooled samples per species) as well as drinking water were cultured for Salmonella. Isolates with identical serotype obtained from index patient and any household sample were defined as “paired isolates” and assessed for genetic relatedness by multilocus variable number tandem-repeat analysis (MLVA) and whole-genome sequencing (WGS). Results Twenty-nine households were visited for 32/42 (76.2%) eligible index patients: two households comprised two index patients each, and in a third household the index patient had a recurrent infection. Among the 32 index patients, serotypes were Salmonella Typhimurium (n = 26), Salmonella Enteritidis (n = 5) and Salmonella Freetown (n = 1). All Typhimurium isolates were sequence type (ST)313. Median delay between blood culture sampling and household visits was 13 days (range 6–26). Salmonella was obtained from 16/186 (8.6%) livestock samples (13 serotypes) and 18/290 (6.2%) household members (9 serotypes). None of the water samples yielded Salmonella. Paired Salmonella Typhimurium isolates were obtained from three households representing four index patients. MLVA types were identical in two pairs and similar in the third (consisting of two index patients and one household member). WGS showed a strong genetic relatedness with 0 to 2 core genome SNPs difference between pairs on a household level. Livestock samples did not yield any Salmonella Typhimurium or Salmonella Enteritidis, and the latter was exclusively obtained from blood culture. Other serotypes shared by human and/or livestock carriers in the same household were Salmonella Derby, Drac, Tennessee and Muenster. Conclusions/Significance The current study provides further evidence of a human reservoir for invasive non-Typhoidal Salmonella (iNTS) in sub-Saharan Africa., Author summary Non-Typhoidal Salmonella—particularly Salmonella Typhimurium sequence type (ST) 313—are among the most common causes of bloodstream infection in children in sub-Saharan Africa. To assess transmission and reservoir of this invasive serotype we performed a blood culture surveillance study among children < 15 years (index patients) in Nanoro, rural Burkina Faso. In case of blood culture confirmed invasive Non-Typhoidal Salmonella (iNTS) infection among index patients a household survey was performed, during which stool samples from household members, stool samples from livestock and water samples were obtained and cultured for Salmonella. Salmonella isolates obtained from blood culture of index patients were compared for genetic relatedness with Salmonella isolates obtained from samples taken from their corresponding household. In three households we found Salmonella Typhimurium ST 313 among both index patient and the stool sample of a household member, we found a strong genetic relatedness within each pair. There were no matching serotypes between index patients and livestock samples or water samples within households. Clusters from other serotypes were restricted to stool samples from household members and different species of livestock. Our results support the theory that iNTS has a human reservoir.

Background: Accurate and timely diagnosis of malaria is essential for disease management and surveillance. Microscopy and malaria rapid diagnostic tests (RDTs) are standard malaria diagnostics, but both methods have significant limitations. The novel automated haematology analyser XN-30 provides standard complete blood counts (CBC) as well as quantification of malaria parasitaemia at the price of an RDT. This study assessed the accuracy of XN-30 for malaria detection in a Controlled Human Malaria Infection (CHMI) study and subsequently in a phase-3 diagnostic accuracy study in Burkina Faso. Methods: Sixteen healthy malaria-naive CHMI participants were challenged according to standardized protocols by exposure to five laboratory reared Plasmodium falciparum-infected mosquitoes and sampled daily for XN-30, blood smear microscopy, RDT and qPCR analyses (NCT02836002). The blinded diagnostic accuracy study included 908 patients aged >3 months, presenting with acute febrile illness (NCT02669823). XN-30, microscopy and RDTs (HRP-2/pLDH) were performed on site, qPCR was done in retrospect. Microscopy was used as reference standard, results were corrected for qPCR confirmed submicroscopic cases. RDT results were compared to XN-30 for both microscopic and qPCR confirmed cases. Findings: All CHMI participants became parasitaemic by qPCR and XN-30 with a strong correlation for parasite density (R2=0·91). In the field study, the sensitivity and specificity of XN-30 compared to microscopy were 98.7% and 99.4% respectively (PPV 98·7%, NPV 99·4%, AUC=0·99). Three microscopy confirmed cases were not detected by XN-30. However, XN-30 detected 24 of 119 (20.2%) qPCR confirmed submicroscopic cases. The sensitivity and specificity of XN-30 to diagnose microscopic cases were higher than that of HRP-2 and pLDH RDTs. Interpretation: XN-30 is a novel rapid automated malaria diagnostic outperforming standard microscopy and RDT's at a similar price. Since it simultaneously provides haemocytometric data and allows high-throughput testing, XN-30 is an attractive diagnostic tool for malaria management and control. Funding Statement: The CHMI study was funded by PATH MVI. Sysmex Corporation provided the analyzer and reagents. The diagnostic accuracy study was funded by Sysmex Corporation. The funding sources were involved in the study design, but not in data collection, analysis and interpretation, or the preparation of the report. Declaration of Interests: AvV and QdM have a non-restricted research grant from SYSMEX, which funded the current study. None of the other authors had any conflict of interest. Ethics Approval Statement: The studies were performed in accordance with the declaration of Helsinki and GCLP guidelines. The CHMI study was approved by the central committee for research involving human subjects (CCMO) of the Netherlands (NL56659.091.16), and the Western Institutional Review Board (WIRB) in the USA. The diagnostic study was approved by the national ethical committee of Burkina Faso (ref 2015-01-006), the internal review board of IRSS (ref A03-2016/CEIRES) the ethical committee of the university hospital of Antwerp (ref 15/47/492) and the institutional review board of the Institute of Tropical Medicine Antwerp (ref 1029/15).

Campylobacter infection is a common cause of diarrhea among international travelers. We studied antibiotic resistance patterns among Campylobacter isolates obtained from international travelers according to travel destination. Three collections of isolates obtained from international travelers between 2007 and 2014 (Institute of Tropical Medicine, the “Laboratoire Hospitalier Universitaire de Bruxelles “and the Belgian National Reference Centre for Campylobacter) were used. Isolates were tested for minimal inhibitory concentration (MIC) values (E-test macromethod) for fluoroquinolones, macrolides, tetracyclines, amoxicillin–clavulanic acid, and meropenem. Single isolates from 261 travelers were available; median (IQR) age was 25.4 (4–42) years, 85.8% were symptomatic (information for 224 patients available). Overall resistance to ciprofloxacin was 60.9%, ranging from 50.8% in Africa to 75.0% in Asia. Resistance to erythromycin was 4.6%, with the highest rate observed for Southern Asia (15.2%, seven isolates, six of them recovered from patients returning from India). A total of 126 isolates (48.3%) were resistant to tetracycline. No resistance to amoxicillin–clavulanic acid or meropenem was detected. Ciprofloxacin resistance tended to increase over time (53.9% in 2007 versus 72.2% in 2014), erythromycin resistance remained stable (median annual resistance 4.2%). Most (86.2%) ciprofloxacin-resistant isolates had MIC values ≥32 mg/l, and all erythromycin-resistant isolates had MIC values ≥256 mg/l. Co-resistance to ciprofloxacin and erythromycin was observed in 11 (4.2%) isolates, seven of which came from Southern Asia. Among all regions of travel, more than half of Campylobacter isolates were resistant to ciprofloxacin. Overall resistance to erythromycin was below 5% but reached 15.2% in Southern Asia., SCOPUS: ar.j, info:eu-repo/semantics/published

BACKGROUND This study reports the microbiological landscape of Salmonella Typhi and invasive nontyphoidal Salmonella (iNTS) in the Democratic Republic of the Congo (DRC). METHODS Blood cultures obtained from hospital-admitted patients suspected of bloodstream infection (BSI) in 4 of 11 provinces in DRC (Kinshasa, Bas-Congo, Equateur, and Orientale) were processed. Sampling had started in 2007; the results for the period 2011-2014 are reported. RESULTS Salmonella Typhi and iNTS were cultured from 194 (1.4%) and 840 (5.9%), respectively, of 14,110 BSI episodes and ranked first among BSI pathogens in adults (65/300 [21.7%]) and children (783/1901 [41.2%]), respectively. A total of 948 of 1034 (91.7%) isolates were available for analysis (164 Salmonella Typhi and 784 iNTS). Salmonella Typhimurium and Salmonella Enteritidis represented 386 (49.2%) and 391 (49.9%), respectively, of iNTS isolates, fluctuating over time and geography and increasing during the rainy season. Adults accounted for

Background Bloodstream infections (BSI) caused by Salmonella Typhi and invasive non-Typhoidal Salmonella (iNTS) frequently affect children living in rural sub-Saharan Africa but data about incidence and serotype distribution are rare. Objective The present study assessed the population-based incidence of Salmonella BSI and severe malaria in a Health and Demographic Surveillance System in a rural area with seasonal malaria transmission in Nanoro, Burkina Faso. Methods Children between 2 months—15 years old with severe febrile illness were enrolled during a one-year surveillance period (May 2013—May 2014). Thick blood films and blood cultures were sampled and processed upon admission. Population-based incidences were corrected for non-referral, health seeking behavior, non-inclusion and blood culture sensitivity. Adjusted incidence rates were expressed per 100,000 person-years of observations (PYO). Results Among children < 5 years old, incidence rates for iNTS, Salmonella Typhi and severe malaria per 100,000 PYO were 4,138 (95% Confidence Interval (CI): 3,740–4,572), 224 (95% CI: 138–340) and 2,866 (95% CI: 2,538–3,233) respectively. Among those aged 5–15 years, corresponding incidence rates were 25 (95% CI: 8–60), 273 (95% CI: 203–355) and 135 (95% CI: 87–195) respectively. Most iNTS occurred during the peak of the rainy season and in parallel with the increase of Plasmodium falciparum malaria; for Salmonella Typhi no clear seasonal pattern was observed. Salmonella Typhi and iNTS accounted for 13.3% and 55.8% of all 118 BSI episodes; 71.6% of iNTS (48/67) isolates were Salmonella enterica serovar Typhimurium and 25.4% (17/67) Salmonella enterica serovar Enteritidis; there was no apparent geographical clustering. Conclusion The present findings from rural West-Africa confirm high incidences of Salmonella Typhi and iNTS, the latter with a seasonal and Plasmodium falciparum-related pattern. It urges prioritization of the development and implementation of Salmonella Typhi as well as iNTS vaccines in this setting.