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BACKGROUND: There is a need to evaluate antibiotic use, duration of therapy, and stewardship in low- and middle-income countries to guide the development of appropriate stewardship programs that are global in scope and effectively decrease unnecessary antibiotic use. METHODS: We prospectively collected information on illness occurrence and antibiotic use from a cohort of 303 children. We evaluated the incidence, duration of therapy, and appropriateness of antibiotic prescriptions by 5 main antibiotic prescribers (physicians and nurses, pharmacists, nursing assistants, self-prescriptions, and neighbors or family members). RESULTS: Ninety percent of children received an antibiotic during follow-up, and on average, by the end of follow-up a child had spent 4.3% of their first 5 years of life on antibiotics. The most frequent prescribers were physicians/nurses (79.4%), followed by pharmacists (8.1%), self-prescriptions (6.8%), nursing assistants (3.7%), and family or neighbors (1.9%). Of the 3702 courses of antibiotics prescribed, 30.9% were done so for the occurrence of fever, 25.3% for diarrhea, 2.8% for acute lower respiratory disease, 2.7% for dysentery, and 38.2% for an undetermined illness. Courses exceeding the recommended duration were common for the principal diseases for which treatment was initiated, with 27.3% of courses exceeding the recommended length duration, representing a potential reduction in 13.2% of days on which this cohort spent on antibiotics. CONCLUSIONS: Stewardship programs should target medical personnel for a primary care stewardship program even in a context in which antibiotics are available to the public with little or no restrictions and appropriate duration should be emphasized in this training.
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Antibacterianos , Personal de Salud , Humanos , Niño , Antibacterianos/uso terapéutico , Estudios de Cohortes , Perú , Prescripciones , Pautas de la Práctica en MedicinaRESUMEN
BACKGROUND: The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile illness in most low- and middle-income countries (LMICs). We designed a semi-quantitative PCR in a modular format to detect bloodborne agents of acute febrile illness that encompassed common etiologies of AFI in the region, etiologies of recent epidemics, etiologies that require an immediate public health response and additional pathogens of unknown endemicity. We then designed a study that would delineate background levels of transmission in the community in the absence of symptoms to provide corrected estimates of attribution for the principal determinants of AFI. METHODS: A case-control study of acute febrile illness in patients ten years or older seeking health care in Iquitos, Loreto, Peru, was planned. Upon enrollment, we will obtain blood, saliva, and mid-turbinate nasal swabs at enrollment with a follow-up visit on day 21-28 following enrollment to attain vital status and convalescent saliva and blood samples, as well as a questionnaire including clinical, socio-demographic, occupational, travel, and animal contact information for each participant. Whole blood samples are to be simultaneously tested for 32 pathogens using TaqMan array cards. Mid-turbinate samples will be tested for SARS-CoV-2, Influenza A and Influenza B. Conditional logistic regression models will be fitted treating case/control status as the outcome and with pathogen-specific sample positivity as predictors to attain estimates of attributable pathogen fractions for AFI. DISCUSSION: The modular PCR platforms will allow for reporting of all primary results of respiratory samples within 72 h and blood samples within one week, allowing for results to influence local medical practice and enable timely public health responses. The inclusion of controls will allow for a more accurate estimate of the importance of specific prevalent pathogens as a cause of acute illness. STUDY REGISTRATION: Project 1791, Registro de Proyectos de Investigación en Salud Pública (PRISA), Instituto Nacional de Salud, Perú.
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COVID-19 , Gripe Humana , Humanos , Perú , Gripe Humana/epidemiología , Estudios de Casos y Controles , SARS-CoV-2 , Fiebre/epidemiología , Reacción en Cadena de la Polimerasa , Instituciones de Salud , Prueba de COVID-19RESUMEN
Existing acute febrile illness (AFI) surveillance systems can be leveraged to identify and characterize emerging pathogens, such as SARS-CoV-2, which causes COVID-19. The US Centers for Disease Control and Prevention collaborated with ministries of health and implementing partners in Belize, Ethiopia, Kenya, Liberia, and Peru to adapt AFI surveillance systems to generate COVID-19 response information. Staff at sentinel sites collected epidemiologic data from persons meeting AFI criteria and specimens for SARS-CoV-2 testing. A total of 5,501 patients with AFI were enrolled during March 2020-October 2021; >69% underwent SARS-CoV-2 testing. Percentage positivity for SARS-CoV-2 ranged from 4% (87/2,151, Kenya) to 19% (22/115, Ethiopia). We show SARS-CoV-2 testing was successfully integrated into AFI surveillance in 5 low- to middle-income countries to detect COVID-19 within AFI care-seeking populations. AFI surveillance systems can be used to build capacity to detect and respond to both emerging and endemic infectious disease threats.
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COVID-19 , Enfermedades Transmisibles , Estados Unidos , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Prueba de COVID-19 , Fiebre/epidemiologíaRESUMEN
BACKGROUND: Deworming programs aimed at reducing morbidity and mortality from geohelminth infections are common in many countries where these infections are endemic, but data demonstrating increasing levels of resistance to albendazole and mebendazole are causes for concern. Studies to evaluate the clinical efficacy of deworming programs are critical to maintain high infection control goals. METHODS: We propose to assess the clinical efficacy of Peruvian national guidelines for deworming programs in a prospective observational study conducted in the Amazon River basin area near Iquitos, Peru. Major outcomes to be evaluated include (1) albendazole resistance of intestinal helminths (trichuriasis, ascariasis, hookworm), and (2) frequency of reinfection with intestinal helminths 4 months after treatment with albendazole. Children ages 2-11 years from the Belén District of Iquitos will be identified based on a community census. Following parental informed consent, demographic data, weight, and height will be recorded and a stool specimen for parasitological exam by direct observation and Kato-Katz concentration method, and helminthic egg counts will be collected prior to administration of albendazole, following Peruvian national guidelines. Follow-up stool specimens examined in the same manner will be collected at 20 days, 90 days, and 100 days following initial administration of albendazole, and based on parasites found repeat treatment will be administered in accordance with national guidelines. Real-time multiplex qPCR will be performed on helminth positive samples collected prior to initial deworming and on helminth-positive specimens detected on day 15-20. A total sample size of 380 participants was calculated based on total population in the target group and prevalence estimates of helminth infections and clinical resistance based on recent data. DISCUSSION: Data from observational clinical efficacy studies are important to guide geohelminth infection control programs. Trial registration https://www.researchregistry.com/ . Identification number: researchregistry7736; Registered retrospectively March 13, 2022; https://www.researchregistry.com/browse-the-registry#home/registrationdetails/622e024cf06132001e3327bf/.
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Antihelmínticos , Helmintiasis , Helmintos , Infecciones por Trematodos , Albendazol/uso terapéutico , Animales , Antihelmínticos/uso terapéutico , Niño , Preescolar , Heces/parasitología , Helmintiasis/tratamiento farmacológico , Helmintiasis/epidemiología , Humanos , Parasitosis Intestinales , Estudios Observacionales como Asunto , Perú/epidemiología , Reinfección , Estudios Retrospectivos , Suelo/parasitología , Infecciones por Trematodos/tratamiento farmacológicoRESUMEN
The objective of this study was to determine the phenotypic patterns of antibiotic resistance and the epidemiology of drug-resistant Campylobacter spp. from a low-resource setting. A birth cohort of 303 patients was followed until 5 years of age. Stool samples from asymptomatic children (n = 10,008) and those with diarrhea (n = 3,175) were cultured for Campylobacter Disk diffusion for ciprofloxacin (CIP), nalidixic acid (NAL), erythromycin (ERY), azithromycin (AZM), tetracycline (TE), gentamicin (GM), ampicillin (AMP), amoxicillin and clavulanic acid (AMC), ceftriaxone (CRO), chloramphenicol (C), and trimethoprim-sulfamethoxazole (TMS) was determined. Antibiotic resistances in Campylobacter jejuni and non-C. jejuni isolates from surveillance and diarrhea samples were compared, and the association between personal macrolide exposure and subsequent occurrence of a macrolide-resistant Campylobacter spp. was assessed. Of 917 Campylobacter isolates, 77.4% of C. jejuni isolates and 79.8% of non-C. jejuni isolates were resistant to ciprofloxacin, while 4.9% of C. jejuni isolates and 24.8% of non-C. jejuni isolates were not susceptible to azithromycin. Of the 303 children, 33.1% had been diagnosed with a Campylobacter strain nonsusceptible to both azithromycin and ciprofloxacin. Personal macrolide exposure did not affect the risk of macrolide-resistant Campylobacter Amoxicillin and clavulanic acid (94.0%) was one of the antibiotics with the highest rates of susceptibility. There is a high incidence of quinolone- and macrolide-resistant Campylobacter infections in infants under 24 months of age. Given the lack of association between personal exposure to macrolides and a subsequent Campylobacter infection resistant to macrolides, there is a need to evaluate the source of multidrug-resistant (MDR) Campylobacter This study provides compelling evidence to propose amoxicillin/clavulanic acid as a treatment for campylobacteriosis.
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Antibacterianos/farmacología , Campylobacter/efectos de los fármacos , Azitromicina/farmacología , Campylobacter/genética , Campylobacter jejuni/efectos de los fármacos , Campylobacter jejuni/genética , Ciprofloxacina/farmacología , Diarrea/microbiología , Farmacorresistencia Bacteriana/genética , Eritromicina/farmacología , Humanos , Pruebas de Sensibilidad Microbiana , Tetraciclina/farmacologíaRESUMEN
PURPOSE OF REVIEW: To review recent findings regarding the control and treatment of campylobacteriosis. RECENT FINDINGS: The application of improved diagnostics has led to an upward shift in the attributable burden of Campylobacter infections, in both the United States and Europe as well as in resource-poor settings. Increased focus has brought a fundamental feature of campylobacteriosis -- the ability to cause relapsing disease back into focus, and expanding data on antimicrobial resistance has lead from a switch in first-line therapy for severe diarrhea from quinolones to azithromycin in most contexts, even as evidence of expanding macrolide resistance emerges. SUMMARY: Campylobacter spp. infection is a common infection worldwide. Antibiotic-resistant Campylobacter spp. has become an emerging threat with the increase in industrial poultry production, as well as the broad use of antibiotics in both animals and humans.
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Infecciones por Campylobacter/tratamiento farmacológico , Infecciones por Campylobacter/prevención & control , Transmisión de Enfermedad Infecciosa/prevención & control , Enfermedades Transmitidas por los Alimentos/tratamiento farmacológico , Enfermedades Transmitidas por los Alimentos/prevención & control , Salud Única/tendencias , Zoonosis/transmisión , Animales , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana , Europa (Continente) , Humanos , Estados Unidos , Zoonosis/prevención & controlRESUMEN
BACKGROUND: Bacillus Calmette-Guerin (BCG) scar formation is considered a visual marker of vaccination and cell-mediated immune response. This study characterized the association between pregnancy and birth characteristics with BCG scar formation. STUDY DESIGN: Pregnant women were enrolled prospectively. Infants were followed up for the first 6 months of life, and the diameter of the BCG scar was recorded. Marginal models were fitted to assess the association of BCG scar diameter with pregnancy and birth characteristics using linear regressions with generalized estimating equations. RESULTS: A total of 307 infants were enrolled, of whom 19.2% (59/307) were of low birth weight. Among those with known gestational age, 7.1% were preterm births (21/295). Overall, 98.7% (303/307) of infants developed a BCG scar. BCG scar trends in a tropical environment, such as the Amazon, differ from the trends evidenced in the capital of Peru. For every additional week of gestational age, the mean scar diameter increased by 0.1 mm (95% confidence interval [CI]: 0.02, 0.24; p = 0.017). Maternal illness during pregnancy impacted BCG scar size, as the infants of mothers who self-report fever had a smaller scar diameter (1 mm, 95% CI: 0.5, 1.8 mm; p = 0.001). CONCLUSION: The immune reaction to the BCG vaccination is affected by gestational age at birth and systemic inflammatory episodes during pregnancy.
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Vacuna BCG/inmunología , Cicatriz/patología , Recien Nacido Prematuro , Vacunación , Cicatriz/inmunología , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido de Bajo Peso , Recién Nacido , Masculino , Perú , Embarazo , Complicaciones Infecciosas del Embarazo , Estudios ProspectivosRESUMEN
Diagnosis of clinical toxoplasmosis remains a challenge, thus limiting the availability of human clinical samples. Though murine models are an approximation of human response, their definitive infection status and tissue availability make them critical to the diagnostic development process. Hydrogel mesh nanoparticles were used to concentrate antigen to detectable levels for mass spectrometry. Seven Toxoplasma gondii isolates were used to develop a panel of potential peptide sequences for detection by parallel reaction monitoring (PRM) mass spectrometry. Nanoparticles were incubated with decreasing concentrations of tachyzoite lysate to explore the limits of detection of PRM. Mice whose toxoplasmosis infection status was confirmed by quantitative real-time PCR had urine tested by PRM after hydrogel mesh concentration for known T. gondii peptides. Peptides from GRA1, GRA12, ROP4, ROP5, SAG1, and SAG2A proteins were detected by PRM after nanoparticle concentration of urine, confirming detection of T. gondii antigen in the urine of an infected mouse.
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Hidrogeles/química , Espectrometría de Masas/métodos , Nanopartículas/química , Proteínas Protozoarias/orina , Toxoplasma/aislamiento & purificación , Toxoplasmosis/diagnóstico , Animales , Femenino , Ratones , Toxoplasmosis/parasitología , Toxoplasmosis/orinaRESUMEN
A 52-yr-old female Nile hippopotamus ( Hippopotamus amphibious ) was presented for acute onset anorexia, depression, lethargy, instability, and weakness in the pelvic limbs. Clinical signs were rapidly progressive, despite empiric therapy with anti-inflammatory medications, resulting in the death of the animal. Gross necropsy evaluation revealed two tan, firm masses in the cerebellum and mesencephalon and a single mass in the right cranial adrenal gland. All three masses had a similar histologic morphology, and immunohistochemical investigation confirmed the general diagnosis of an adenocarcinoma, but the exact cell of origin remains unclear. In addition, there was evidence of neuroendocrine differentiation in the adrenal gland and not in the brain. These findings suggest either two distinct neoplastic populations or a metastasizing adenocarcinoma with focal endocrine differentiation. In dogs, anal sac and clitoral adenocarcinomas have been reported to undergo focal endocrine differentiation, and both can cause widespread metastasis while the primary lesion can be small. A small neoplasm of these glands may have been missed on gross examination.
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Adenocarcinoma/veterinaria , Neoplasias Encefálicas/veterinaria , Cerebelo/patología , Mesencéfalo/patología , Adenocarcinoma/patología , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/veterinaria , Glándulas Suprarrenales/patología , Animales , Artiodáctilos , Neoplasias Encefálicas/patologíaRESUMEN
Campylobacter causes bacterial enteritis, dysentery, and growth faltering in children in low- and middle-income countries (LMICs). Campylobacter spp. are fastidious organisms, and their detection often relies on culture independent diagnostic technologies, especially in LMICs. Campylobacter jejuni and Campylobacter coli are most often the infectious agents and in high income settings together account for 95% of Campylobacter infections. Several other Campylobacter species have been detected in LMIC children at an increased prevalence relative to high income settings. After doing extensive whole genome sequencing of isolates of C. jejuni and C. coli in Peru, we observed heterogeneity in the binding sites for the main species-specific PCR assay (cadF) and designed an alternative rpsKD-based qPCR assay to detect both C. jejuni and C. coli. The rpsKD-based qPCR assay identified 23% more C.jejuni/ C.coli samples than the cadF assay among 47 Campylobacter genus positive cadF negative samples verified to have C. jejuni and or C. coli with shotgun metagenomics. This assay can be expected to be useful in diagnostic studies of enteric infectious diseases and be useful in revising the attribution estimates of Campylobacter in LMICs.
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Infecciones por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Niño , Humanos , Campylobacter coli/genética , Reacción en Cadena de la Polimerasa , Infecciones por Campylobacter/diagnóstico , Infecciones por Campylobacter/microbiología , Heces/microbiologíaRESUMEN
Background: The Enterics for Global Health (EFGH) Peru site will enroll subjects in a periurban area of the low Amazon rainforest. The political department of Loreto lags behind most of Peru in access to improved sources of water and sanitation, per capita income, children born <2.5â kg, and infant and child mortality. Chronic undernutrition as manifested by linear growth shortfalls is common, but wasting and acute malnutrition are not. Methods: The recruitment of children seeking care for acute diarrheal disease takes place at a geographic cluster of government-based primary care centers in an area where most residents are beneficiaries of free primary healthcare. Results: Rates of diarrheal disease, dysentery, and Shigella are known to be high in the region, with some of the highest rates of disease documented in the literature and little evidence in improvement over the last 2 decades. This study will update estimates of shigellosis by measuring the prevalence of Shigella by polymerase chain reaction and culture in children seeking care and deriving population-based estimates by measuring healthcare seeking at the community level. Conclusions: Immunization has been offered universally against rotavirus in the region since 2009, and in a context where adequate water and sanitation are unlikely to obtain high standards in the near future, control of principal enteropathogens through immunization may be the most feasible way to decrease the high burden of disease in the area in the near future.
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OBJECTIVES: Antimicrobial resistant (AMR) Campylobacter is a global health threat; however, there is limited information on genomic determinants of resistance in low- and middle-income countries. We evaluated genomic determinants of AMR using a collection of whole genome sequenced Campylobacter jejuni and C. coli isolates from Iquitos, Peru. METHODS: Campylobacter isolates from two paediatric cohort studies enriched with isolates that demonstrated resistance to ciprofloxacin and azithromycin were sequenced and mined for AMR determinants. RESULTS: The gyrA mutation leading to the Thr86Ile amino acid change was the only gyrA mutation associated with fluoroquinolone resistance identified. The A2075G mutation in 23S rRNA was present, but three other 23S rRNA mutations previously associated with macrolide resistance were not identified. A resistant-enhancing variant of the cmeABC efflux pump genotype (RE-cmeABC) was identified in 36.1% (35/97) of C. jejuni genomes and 17.9% (12/67) of C. coli genomes. Mutations identified in the CmeR-binding site, an inverted repeat sequence in the cmeABC promoter region that increases expression of the operon, were identified in 24/97 C. jejuni and 14/67 C. coli genomes. The presence of these variants, in addition to RE-cmeABC, was noted in 18 of the 24 C. jejuni and 9 of the 14 C. coli genomes. CONCLUSIONS: Both RE-cmeABC and mutations in the CmeR-binding site were strongly associated with the MDR phenotype in C. jejuni and C. coli. This is the first report of RE-cmeABC in Peru and suggests it is a major driver of resistance to the principal therapies used to treat human campylobacteriosis in this setting.
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Antibacterianos , Campylobacter , Humanos , Niño , Antibacterianos/farmacología , Perú , ARN Ribosómico 23S/genética , Farmacorresistencia Bacteriana/genética , Macrólidos , Campylobacter/genética , GenómicaRESUMEN
In countries where soil-transmitted helminth (STH) infections are endemic, deworming programs are recommended to reduce morbidity; however, increasing levels of resistance to benzimidazoles are of concern. In an observational study in Peru, we studied the clinical efficacy of 400 mg of albendazole 20 days after treatment among children aged 2-11 years. Of 426 participants who provided samples, 52.3% were infected with a STH, 144 (33.8%) were positive for Ascaris (41.8% light, 50.8% moderate, and 7.4% heavy infections), 147 (34.5%) were positive for Trichuris (75.2% light, 22.5% moderate, and 2.3% heavy infections), and 1.1% were positive for hookworm species (100% light infections). Additional stool samples were examined at 20, 90, and 130 days after the initial treatment. At 20 days post-administration of albendazole, the cure rate (CR) of Ascaris infection was 80.1% (95% CI: 73.5-86.7), and the egg reduction rate (ERR) was 70.8% (95% CI: 57.8-88.7); the CR for Trichuris infection was 27.1% (95% CI: 20.0-34.3), and the ERR was 29.8% (95% CI: -1.40 to 57.5). Among participants with persistent or recurrent infections with Trichuris, the combined therapy of albendazole (400 mg) and ivermectin at 600 µg/dose increased overall CR for Trichuris infection to 75.2% (95% CI: 67.3-83.2%) with an ERR of 84.2% (95% CI: 61.3-93.8%). Albendazole administration alone for the control of STH was associated with high rates of treatment failure, especially for Trichuris. Combined single doses of albendazole and ivermectin was observed to have improved efficacy.
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Albendazol , Antihelmínticos , Helmintiasis , Ivermectina , Suelo , Humanos , Albendazol/uso terapéutico , Albendazol/administración & dosificación , Perú/epidemiología , Preescolar , Niño , Ivermectina/uso terapéutico , Ivermectina/administración & dosificación , Masculino , Femenino , Suelo/parasitología , Helmintiasis/tratamiento farmacológico , Helmintiasis/epidemiología , Antihelmínticos/uso terapéutico , Antihelmínticos/administración & dosificación , Heces/parasitología , Quimioterapia Combinada , Animales , Resultado del Tratamiento , Tricuriasis/tratamiento farmacológico , Tricuriasis/epidemiología , Ascariasis/tratamiento farmacológico , Ascariasis/epidemiología , Trichuris/efectos de los fármacosRESUMEN
Background: Rigorous data management systems and planning are essential to successful research projects, especially for large, multicountry consortium studies involving partnerships across multiple institutions. Here we describe the development and implementation of data management systems and procedures for the Enterics For Global Health (EFGH) Shigella surveillance study-a 7-country diarrhea surveillance study that will conduct facility-based surveillance concurrent with population-based enumeration and a health care utilization survey to estimate the incidence of Shigella--associated diarrhea in children 6 to 35 months old. Methods: The goals of EFGH data management are to utilize the knowledge and experience of consortium members to collect high-quality data and ensure equity in access and decision-making. During the planning phase before study initiation, a working group of representatives from each EFGH country site, the coordination team, and other partners met regularly to develop the data management systems for the study. Results: This resulted in the Data Management Plan, which included selecting REDCap and SurveyCTO as the primary database systems. Consequently, we laid out procedures for data processing and storage, study monitoring and reporting, data quality control and assurance activities, and data access. The data management system and associated real-time visualizations allow for rapid data cleaning activities and progress monitoring and will enable quicker time to analysis. Conclusions: Experiences from this study will contribute toward enriching the sparse landscape of data management methods publications and serve as a case study for future studies seeking to collect and manage data consistently and rigorously while maintaining equitable access to and control of data.
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Background: Shigella is a leading cause of acute watery diarrhea, dysentery, and diarrhea-attributed linear growth faltering, a precursor to stunting and lifelong morbidity. Several promising Shigella vaccines are in development and field efficacy trials will require a consortium of potential vaccine trial sites with up-to-date Shigella diarrhea incidence data. Methods: The Enterics for Global Health (EFGH) Shigella surveillance study will employ facility-based enrollment of diarrhea cases aged 6-35 months with 3 months of follow-up to establish incidence rates and document clinical, anthropometric, and financial consequences of Shigella diarrhea at 7 country sites (Mali, Kenya, The Gambia, Malawi, Bangladesh, Pakistan, and Peru). Over a 24-month period between 2022 and 2024, the EFGH study aims to enroll 9800 children (1400 per country site) between 6 and 35 months of age who present to local health facilities with diarrhea. Shigella species (spp.) will be identified and serotyped from rectal swabs by conventional microbiologic methods and quantitative polymerase chain reaction. Shigella spp. isolates will undergo serotyping and antimicrobial susceptibility testing. Incorporating population and healthcare utilization estimates from contemporaneous household sampling in the catchment areas of enrollment facilities, we will estimate Shigella diarrhea incidence rates. Conclusions: This multicountry surveillance network will provide key incidence data needed to design Shigella vaccine trials and strengthen readiness for potential trial implementation. Data collected in EFGH will inform policy makers about the relative importance of this vaccine-preventable disease, accelerating the time to vaccine availability and uptake among children in high-burden settings.
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Background: Molecular diagnostics on human fecal samples have identified a larger burden of shigellosis than previously appreciated by culture. Evidence of fold changes in immunoglobulin G (IgG) to conserved and type-specific Shigella antigens could be used to validate the molecular assignment of type-specific Shigella as the etiology of acute diarrhea and support polymerase chain reaction (PCR)-based microbiologic end points for vaccine trials. Methods: We will test dried blood spots collected at enrollment and 4 weeks later using bead-based immunoassays for IgG to invasion plasmid antigen B and type-specific lipopolysaccharide O-antigen for Shigella flexneri 1b, 2a, 3a, and 6 and Shigella sonnei in Shigella-positive cases and age-, site-, and season-matched test-negative controls from all sites in the Enterics for Global Health (EFGH) Shigella surveillance study. Fold antibody responses will be compared between culture-positive, culture-negative but PCR-attributable, and PCR-positive but not attributable cases and test-negative controls. Age- and site-specific seroprevalence distributions will be identified, and the association between baseline antibodies and Shigella attribution will be estimated. Conclusions: The integration of these assays into the EFGH study will help support PCR-based attribution of acute diarrhea to type-specific Shigella, describe the baseline seroprevalence of conserved and type-specific Shigella antibodies, and support correlates of protection for immunity to Shigella diarrhea. These insights can help support the development and evaluation of Shigella vaccine candidates.
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Background: Quantitative polymerase chain reaction (qPCR) targeting ipaH has been proven to be highly efficient in detecting Shigella in clinical samples compared to culture-based methods, which underestimate Shigella burden by 2- to 3-fold. qPCR assays have also been developed for Shigella speciation and serotyping, which is critical for both vaccine development and evaluation. Methods: The Enterics for Global Health (EFGH) Shigella surveillance study will utilize a customized real-time PCR-based TaqMan Array Card (TAC) interrogating 82 targets, for the detection and differentiation of Shigella spp, Shigella sonnei, Shigella flexneri serotypes, other diarrhea-associated enteropathogens, and antimicrobial resistance (AMR) genes. Total nucleic acid will be extracted from rectal swabs or stool samples, and assayed on TAC. Quantitative analysis will be performed to determine the likely attribution of Shigella and other particular etiologies of diarrhea using the quantification cycle cutoffs derived from previous studies. The qPCR results will be compared to conventional culture, serotyping, and phenotypic susceptibility approaches in EFGH. Conclusions: TAC enables simultaneous detection of diarrheal etiologies, the principal pathogen subtypes, and AMR genes. The high sensitivity of the assay enables more accurate estimation of Shigella-attributed disease burden, which is critical to informing policy and in the design of future clinical trials.
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Background: The COVID-19 pandemic has caused societal disruption globally, and South America has been hit harder than other lower-income regions. This study modeled the effects of six weather variables on district-level SARS-CoV-2 reproduction numbers (Rt ) in three contiguous countries of tropical Andean South America (Colombia, Ecuador, and Peru), adjusting for environmental, policy, healthcare infrastructural and other factors. Methods: Daily time-series data on SARS-CoV-2 infections were sourced from the health authorities of the three countries at the smallest available administrative level. Rt values were calculated and merged by date and unit ID with variables from a unified COVID-19 dataset and other publicly available sources for May-December, 2020. Generalized additive models were fitted. Findings: Relative humidity and solar radiation were inversely associated with SARS-CoV-2 Rt . Days with radiation above 1000 kJ/m2 saw a 1.3% reduction in Rt , and those with humidity above 50% recorded a 0.9% reduction in Rt . Transmission was highest in densely populated districts, and lowest in districts with poor healthcare access and on days with lowest population mobility. Wind speed, temperature, region, aggregate government policy response, and population age structure had little impact. The fully adjusted model explained 4.3% of Rt variance. Interpretation: Dry atmospheric conditions of low humidity increase district-level SARS-CoV-2 reproduction numbers, while higher levels of solar radiation decrease district-level SARS-CoV-2 reproduction numbers - effects that are comparable in magnitude to population factors like lockdown compliance. Weather monitoring could be incorporated into disease surveillance and early warning systems in conjunction with more established risk indicators and surveillance measures. Funding: NASA's Group on Earth Observations Work Programme (16-GEO16-0047).
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Background: The study of the etiology of acute febrile illness (AFI) has historically been designed as a prevalence of pathogens detected from a case series. This strategy has an inherent unrealistic assumption that all pathogen detection allows for causal attribution, despite known asymptomatic carriage of the principal causes of acute febrile illness in most low- and middle-income countries (LMICs). We designed a semi-quantitative PCR in a modular format to detect bloodborne agents of acute febrile illness that encompassed common etiologies of AFI in the region, etiologies of recent epidemics, etiologies that require an immediate public health response and additional pathogens of unknown endemicity. We then designed a study that would delineate background levels of transmission in the community in the absence of symptoms to provide corrected estimates of attribution for the principal determinants of AFI. Methods: A case-control study of acute febrile illness in patients ten years or older seeking health care in Iquitos, Loreto, Peru, was planned. Upon enrollment, we will obtain blood, saliva, and mid-turbinate nasal swabs at enrollment with a follow-up visit on day 21-28 following enrollment to attain vital status and convalescent saliva and blood samples, as well as a questionnaire including clinical, socio-demographic, occupational, travel, and animal contact information for each participant. Whole blood samples are to be simultaneously tested for 32 pathogens using TaqMan array cards. Mid-turbinate samples will be tested for SARS-CoV-2, Influenza A and Influenza B. Conditional logistic regression models will be fitted treating case/control status as the outcome and with pathogen-specific sample positivity as predictors to attain estimates of attributable pathogen fractions for AFI. Discussion: The modular PCR platforms will allow for reporting of all primary results of respiratory samples within 72 hours and blood samples within one week, allowing for results to influence local medical practice and enable timely public health responses. The inclusion of controls will allow for a more accurate estimate of the importance of specific, prevalent pathogens as a cause of acute illness. Study Registration: Project 1791, Registro de Proyectos de Investigación en Salud Pública (PRISA), Instituto Nacional de Salud, Perú.
RESUMEN
Peruvian veterinarians and animal care workers (VACW) are primary responders in the event of disasters or emergencies, yet they face unique concerns that could impede or block their essential functions in public health preparedness in comparison with VACWs in other countries. In this study, we used the Ready, Willing, and Able model via electronic survey to evaluate the perception of risks and barriers that Peruvian VACWs faced when deciding whether to continue working during the COVID-19 pandemic between July and December 2020. We used logistic regression models to evaluate associations between demographic characteristics, perceived role, and contact scores with 8 outcomes: knowledge of COVID-19; confidence in safety protocols; perceived threat; perceived job efficacy; perceived barriers; and readiness, willingness, and ability to respond to the COVID-19 pandemic. Less than 50% of respondents reported barriers to report to work during the pandemic. Respondents who reported higher contact with coworkers had an increased confidence in safety protocols (OR 5.16; 95% CI, 1.36 to 19.61) and willingness (OR 3.76; 95% CI, 1.14 to 12.47) to respond to the pandemic. Close contacts with essential workers and higher economic income were associated with higher reported knowledge of COVID-19. Respondents with higher perceived job efficacy had higher odds of reporting being ready, willing, and able to respond to COVID-19, while those who identified more barriers to report to work had lower odds of being ready, willing, and able to respond. The findings from this study, which showed differences from VACWs in the United States, can be used by individuals designing programs to improve pandemic and disaster preparedness in this essential, yet understudied and vulnerable, workforce.