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1.
Medicine (Baltimore) ; 100(5): e23786, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33592835

RESUMEN

ABSTRACT: Community acquired-pneumonia (CAP) has varying causative pathogens and clinical characteristics. This study investigated the prevalence of Mycoplasma pneumoniae (M pneumoniae) and evaluated the clinical characteristics in infected hospitalized children by disease severity.From throat swabs of hospitalized children (5 months to 14 years) with CAP collected between November 2017 and May 2018, M pneumoniae and other CAP pathogens were identified using polymerase chain reaction (PCR). Differences in clinical and laboratory test data were compared between severe and mild case groups.Of 333 hospitalized children enrolled, 221/333 (66.4%) tested positive for M pneumoniae and 24/221 (10.9%) patients were (n = 9, aged <5 years vs n = 15, ≥5 years) single infection by PCR, however, only 170/333 (51.1%) patients were presented with M pneumoniae IgM-positive. M pneumoniae detection rate by PCR was higher than by immunoglobulin (IgM) serology. In 123/221 (55.7%) M pneumoniae infected patients, coinfection with bacterial pathogens (n = 61, <5 years vs n = 62, ≥5 years) occurred. Children (aged 3-8 years) had most M pneumoniae infection. Severe M pneumoniae pneumonia (MPP) in children occurred mostly in older age (7 [interquartile ranges {IQR}, 6-8] years; P < .0001), with longer cough days (14 [IQR, 10-19.5] days; P = .002) and hospitalization duration (9.5 [IQR, 7-12.3] days; P < .0001), lower lymphocyte ratio (24.1, [IQR, 20.0-31.1] %; P = .001), higher neutrophils ratio (66.0, [IQR, 60.2-70.3]%; P < .0001), and serum C-reactive protein (CRP) level (3.8, [IQR, 1.3-10.9] mg/L; P = .027).M pneumoniae is the most commonly detected pathogen in CAP. High coinfection prevalence increases diagnosis difficulty by clinically nonspecific characteristics. M pneumoniae detection by PCR with IgM may improve precise and reliable diagnosis of community-acquired MPP.


Asunto(s)
Niño Hospitalizado/estadística & datos numéricos , Infecciones Comunitarias Adquiridas/epidemiología , Mycoplasma pneumoniae/aislamiento & purificación , Neumonía por Mycoplasma/epidemiología , Adolescente , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Niño , Preescolar , China/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Femenino , Humanos , Inmunoglobulina M/sangre , Inmunoglobulina M/inmunología , Lactante , Masculino , Mycoplasma pneumoniae/inmunología , Neumonía por Mycoplasma/microbiología , Reacción en Cadena de la Polimerasa , Prevalencia
2.
BMC Infect Dis ; 21(1): 69, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33441087

RESUMEN

BACKGROUND: Scrub typhus is a mite-borne infectious disease caused by Orientia tsutsugamushi. Few follow-up studies have assessed antibody titers using serologic tests from various commercial laboratories and the Korea Centers for Disease Control and Prevention (KCDC). METHODS: A prospective study to assess the antibody titers in patients with scrub typhus and seroprevalence in individuals undergoing health checkups was conducted using results of immunofluorescence antibody assays (IFAs) and serologic tests, used by the KCDC and commercial laboratories, respectively. The following tests were performed simultaneously: (i) indirect IFA used by the KCDC to detect immunoglobulin (Ig) M and IgG, (ii) IFA used by a commercial laboratory to detect total Ig, and (iii) antibody tests using two commercially available kits. RESULTS: When the IgM and IgG cutoff values (≥1:16 and ≥1:256, respectively) used in the IFA and the total IgG cutoff values (≥1:40) were used in prospective follow-up investigations, the antibody positivity rates of 102 patients with scrub typhus were 44.1, 35.3, and 57.6%, respectively, within 5 days of symptom onset. Among 91 individuals who recovered from scrub typhus, the follow-up IgM, IgG, and total Ig positivity rates for 13 years were 37.4% (34/91), 22.0% (20/91), and 76.9% (70/91), respectively. Among 216 individuals undergoing health checkups, the seroprevalence of IgM was 4.2% (9/216); no seroprevalence of IgG was observed. CONCLUSIONS: IFAs used by the KCDC and the commercial laboratory and rapid commercial kits could not distinguish between patients who had recovered from scrub typhus and those who are currently infected with O. tsutsugamushi. In South Korea and other countries, where low antibody cutoff values are used, upward adjustments of cutoff values may be necessary.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Orientia tsutsugamushi/inmunología , Tifus por Ácaros/sangre , Tifus por Ácaros/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , República de Corea/epidemiología , Tifus por Ácaros/epidemiología , Tifus por Ácaros/microbiología , Estudios Seroepidemiológicos , Pruebas Serológicas/métodos , Adulto Joven
3.
BMC Infect Dis ; 20(1): 822, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33172393

RESUMEN

BACKGROUND: Plague, a fatal disease caused by the bacillus, Yersinia pestis, still affects resources-limited countries. Information on antibody response to plague infection in human is scarce. Anti-F1 Ig G are among the known protective antibodies against Y. pestis infection. As a vaccine preventable disease, knowledge on antibody response is valuable for the development of an effective vaccine to reduce infection rate among exposed population in plague-endemic regions. In this study, we aim to describe short and long-term humoral immune responses against Y. pestis in plague-confirmed patients from Madagascar, the most affected country in the world. METHODS: Bubonic (BP) and pneumonic plague (PP) patients were recruited from plague- endemic foci in the central highlands of Madagascar between 2005 and 2017. For short-term follow-up, 6 suspected patients were enrolled and prospectively investigated for kinetics of the anti-F1 IgG response, whereas the persistence of antibodies was retrospectively studied in 71 confirmed convalescent patients, using an ELISA which was validated for the detection of plague in human blood samples in Madagascar. RESULTS: Similarly to previous findings, anti-F1 IgG rose quickly during the first week after disease onset and increased up to day 30. In the long-term study, 56% of confirmed cases remained seropositive, amongst which 60 and 40% could be considered as high- and low-antibody responders, respectively. Antibodies persisted for several years and up to 14.8 years for one individual. Antibody titers decreased over time but there was no correlation between titer and time elapsed between the disease onset and serum sampling. In addition, the seroprevalence rate was not significantly different between gender (P = 0.65) nor age (P = 0.096). CONCLUSION: Our study highlighted that the circulating antibody response to F1 antigen, which is specific to Y. pestis, may be attributable to individual immune responsiveness. The finding that a circulating anti-F1 antibody titer could persist for more than a decade in both BP and PP recovered patients, suggests its probable involvement in patients' protection. However, complementary studies including analyses of the cellular immune response to Y. pestis are required for the better understanding of long-lasting protection and development of a potential vaccine against plague.


Asunto(s)
Inmunidad Humoral , Peste/inmunología , Yersinia pestis/inmunología , Adolescente , Adulto , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Niño , Femenino , Estudios de Seguimiento , Humanos , Inmunoglobulina G/sangre , Madagascar/epidemiología , Masculino , Peste/epidemiología , Peste/microbiología , Estudios Prospectivos , Estudios Retrospectivos , Estudios Seroepidemiológicos , Adulto Joven
4.
Nat Commun ; 11(1): 4994, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33020485

RESUMEN

Serogroup B meningococcus (MenB) is a leading cause of meningitis and sepsis across the world and vaccination is the most effective way to protect against this disease. 4CMenB is a multi-component vaccine against MenB, which is now licensed for use in subjects >2 months of age in several countries. In this study, we describe the development and use of an ad hoc protein microarray to study the immune response induced by the three major 4CMenB antigenic components (fHbp, NHBA and NadA) in individual sera from vaccinated infants, adolescents and adults. The resulting 4CMenB protein antigen fingerprinting allowed the identification of specific human antibody repertoire correlating with the bactericidal response elicited in each subject. This work represents an example of epitope mapping of the immune response induced by a multicomponent vaccine in different age groups with the identification of protective signatures. It shows the high flexibility of this microarray based methodology in terms of high-throughput information and minimal volume of biological samples needed.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Adolescente , Adulto , Anticuerpos Antibacterianos/sangre , Niño , Preescolar , Mapeo Epitopo , Humanos , Lactante , Infecciones Meningocócicas/prevención & control , Biblioteca de Péptidos , Análisis por Matrices de Proteínas , Determinación de Anticuerpos Séricos Bactericidas , Adulto Joven
5.
PLoS One ; 15(10): e0240040, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33002056

RESUMEN

INTRODUCTION: To prevent gastric cancer, it is important to accurately determine the presence of Helicobacter pylori (HP) infection. However, correctly identifying HP-uninfected individuals is difficult when using the combination of HP antibody and pepsinogen (PG). OBJECTIVE: The aim of this study was to discriminate true HP-uninfected individuals from others without the need for endoscopic examination. METHODS: A total of 684 subjects with no history of HP eradication who underwent a medical checkup at our hospital were enrolled. The "true uninfected individuals" were determined by a negative stool antigen test and no endoscopic findings of HP-associated gastritis. HP antibody was measured by the latex immunoassay method. Logistic regression analysis using a combination of noninvasive parameters was performed to develop a formula for predicting true uninfected individuals. RESULTS: A total of 528 subjects were classified as true uninfected individuals. Logistic regression analysis showed that statistically significant factors for true uninfected individuals were age (p < 0.001), HP antibody (p <0.001), PGI (p <0.001), and PGII (p = 0.012). The areas under the curve (AUCs) for true uninfected individuals were the highest (0.944) upon applying the prediction formula including four parameters: age, HP antibody, PGI, and PGII. Both the sensitivity and the specificity of the four-parameter prediction formula were higher than those of the traditional three-parameter model using HP antibody, PGI, and PGI/II ratio (sensitivity: 93.2% vs. 86.6% and specificity: 88.5% vs. 82.7%). CONCLUSIONS: Our findings suggest that a model with a combination of four noninvasive parameters is useful for predicting true HP-uninfected individuals without the need for endoscopic examination.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/fisiología , Pepsinógeno A/sangre , Adulto , Factores de Edad , Anciano , Anticuerpos Antibacterianos/inmunología , Área Bajo la Curva , Femenino , Gastritis/complicaciones , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/inmunología , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad
6.
PLoS One ; 15(9): e0238398, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32870922

RESUMEN

OBJECTIVES: Pertussis remains endemic despite high vaccine coverage in infants and toddlers. Pertussis vaccines confer protection but immunity wanes overtime and boosters are needed in a lifetime. Iran, eligible for the Expanded Program on Immunization that includes the primary immunization, implemented two additional booster doses using a whole-cell vaccine (wPV) at 18 months-old and about 6 years-old. Duration of protection induced by the wPVs currently in use and their impact as pre-school booster are not well documented. This study aimed at assessing vaccination compliance and at estimating the duration of protection conferred by vaccination with wPV in children aged < 15 years in Tehran, Iran. METHODS: Detailed information on vaccination history and capillary blood samples were obtained from 1047 children aged 3-15 years who completed the 3 doses-primary pertussis immunization, in Tehran. Anti-pertussis toxin IgG levels were quantified by ELISA. RESULTS: Compliance was very high with 93.3% of children who received the three primary and 1st booster doses in a timely manner. Timeliness of the 2nd booster was lower (63.3%). Rate of seropositive samples continuously and significantly increased from 1-2 to 5-6 years after 1st booster attaining 30.4% of children exhibiting serological sign of recent contact with B. pertussis. Second booster dating back 1 or 2 years was associated with high antibody titers, which significantly decreased within 3 years from injection. Among children who received 2nd booster injection more than 2 years before serum analysis, seroprevalence of pertussis infection was 8.4% and seropositivity rate was higher from the 10 years-old group. CONCLUSION: Seropositivity in children aged 6-7 years with no 2nd booster supports the need for a vaccination at that age. Adolescent booster may also be considered.


Asunto(s)
Tos Ferina/epidemiología , Adolescente , Factores de Edad , Anticuerpos Antibacterianos/sangre , Bordetella pertussis/inmunología , Niño , Preescolar , Femenino , Humanos , Esquemas de Inmunización , Inmunización Secundaria , Inmunoglobulina G/sangre , Irán/epidemiología , Masculino , Vacuna contra la Tos Ferina/administración & dosificación , Estudios Seroepidemiológicos , Tos Ferina/inmunología , Tos Ferina/prevención & control
8.
Sheng Wu Gong Cheng Xue Bao ; 36(8): 1672-1678, 2020 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-32924365

RESUMEN

To investigate the detection threshold of Treponema pallidum specific antibody method by chemiluminescent immunoassay (CLIA) in Siemens ADVIA Centaur XP for Syphilis serological test, and compare with the results derived from CMIA, TP-WB and TPPA method. The result can serve as reference for the application of CLIA. In total 30 887 samples screened by Treponema pallidum specific antibody method were collected by Abbott architect i2000 CMIA from July 2018 to July 2019 in Yanda Hospital of Hebei Province. We selected 153 patients with the ratio of sample absorbance to critical value (S/CO) of 1-9 by CMIA screening of Treponema pallidum specific antibody as the research objects. The reverse sequence of syphilis serological detection was adopted, and TP-WB and TPPA were used as the confirmation methods respectively. MedCalc software was used to analyze the results of ROC curve, and the cut-off value was obtained. Chi square test was used to test the difference significance of counting data. The detection results of Treponema pallidum specific antibody in the same batch of serum samples were unequal by different methods. There was no significant difference between CLIA method and TPPA method, but significant difference between CLIA method with TP-WB method and CMIA method was found. TPPA test results and TP-WB test results were taken as gold standards, ROC curve analysis showed that the best diagnostic cutoff value of CLIA method was 4.01 and 16.06, respectively, and the area under the curve was 0.961 and 0.838. The suggested cutoff value of CLIA method is quite different when using different syphilis serological test methods as the gold standard, Therefore, when the S/CO value determined by CLIA is between 1.00 to 16.06, TP-WB method should be recommended as the first choice in laboratory serological test for recheck and confirmation to avoid clinical misdiagnosis.


Asunto(s)
Anticuerpos Antibacterianos , Serodiagnóstico de la Sífilis , Treponema pallidum , Anticuerpos Antibacterianos/sangre , Humanos , Mediciones Luminiscentes , Serodiagnóstico de la Sífilis/métodos , Serodiagnóstico de la Sífilis/normas
9.
JAMA ; 324(11): 1068-1077, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32930758

RESUMEN

Importance: The standard schedule of national immunization programs for infants may not be sufficient to protect extremely and very preterm infants. Objective: To evaluate the immunogenicity of routine vaccinations administered to preterm infants. Design, Setting, and Participants: A multicenter, prospective, observational cohort study of preterm infants stratified according to gestational age recruited from 8 hospitals across the Netherlands between October 2015 and October 2017, with follow-up until 12 months of age (October 2018). In total, 296 premature infants were enrolled and compared with a control group of 66 healthy term infants from a 2011 study, immunized according to the same schedule with the same vaccines. Exposures: Three primary doses of the diphtheria-tetanus toxoids-acellular pertussis-inactivated poliomyelitis-Haemophilus influenza type b-hepatitis B combination vaccine were given at 2, 3, and 4 months after birth followed by a booster at 11 months and a 10-valent pneumococcal conjugate vaccine at 2, 4, and 11 months after birth. Main Outcomes and Measures: Primary end points were (1) proportion of preterm infants who achieved IgG antibody against vaccine antigens at concentrations above the internationally defined threshold for protection after the primary series and booster dose and (2) serum IgG geometric mean concentrations after the primary series and booster vaccination. Proportions and geometric mean concentrations were compared in preterm infants and the control group of term infants. Results: Of 296 preterm infants (56.1% male; mean gestational age, 30 weeks), complete samples before vaccination, 1 month after the primary series, and 1 month after the booster were obtained from 220 preterm infants (74.3%). After the primary series, the proportion of preterm infants across all gestational age groups who achieved protective IgG antibody levels against pertussis toxin, diphtheria, tetanus and 6 of 10 pneumococcal serotypes varied between 83.0% and 100%, Haemophilus influenzae type b between 34.7% and 46.2% (40.6% among all preterm infants overall), and pneumococcal serotypes 4, 6B, 18C, and 23F between 45.8% and 75.1%. After the booster dose, protective antibody levels were achieved in more than 95% of all preterm groups, except for Haemophilus influenzae type b (88.1%). In general, geometric mean concentrations of all vaccine-induced antibodies were significantly lower in all preterm infants vs term infants, except for pertussis toxin and pneumococcal serotypes 4 and 19F after the primary series and booster vaccination. Conclusions and Relevance: Among preterm infants, administration of routine vaccinations during the first year of life was associated with protective antibody levels against most antigens in the majority of infants after the primary series and booster, except for Haemophilus influenzae type b. However, antibody concentrations were generally lower among preterm infants compared with historical controls.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Inmunoglobulina G/sangre , Recien Nacido Prematuro/inmunología , Vacunas/inmunología , Estudios de Cohortes , Vacuna contra Difteria, Tétanos y Tos Ferina/inmunología , Femenino , Vacunas contra Haemophilus/inmunología , Estudio Históricamente Controlado , Humanos , Inmunización Secundaria , Lactante , Masculino , Vacunas Neumococicas/inmunología , Vacuna Antipolio de Virus Inactivados/inmunología , Vacunas Conjugadas/inmunología
10.
PLoS One ; 15(9): e0239260, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32931511

RESUMEN

Coxiella burnetii is a highly infectious zoonotic pathogen infecting wide range of mammals, including humans. In the present study, a total of 711 blood samples from bovines [cattle (n = 543) and buffaloes (n = 168)] from eight farms at different geographical locations in India were screened for C. burnetii targeting the IS1111 and the com1 genes. The anti-C. burnetii antibodies in serum samples were detected using indirect-ELISA kits. Also, a total of 21 parameters pertaining to animal health and farm management were identified to assess their role as possible risk factors for coxiellosis among the targeted farms. The apparent prevalence (positive for PCR and/or ELISA) for coxiellosis was reported to be 24.5% in cattle and 8.9% in buffaloes. In cattle, the detection rate of C. burnetii employing the IS1111 gene (8.5%) was found to be significantly higher (p<0.05) as compared to the com1 (6.5%) gene. The seropositivity by ELISA was higher among cattle (17.7%) than in buffaloes (8.3%). Further, on univariable analysis of risk factors, species (cattle) (OR:3.31; 95%CI:1.88-5.82), inadequate floor spacing (OR:1.64; 95%CI:1.10-2.43), mastitis (OR:2.35, 95%CI:1.45-3.81) and reproductive disorders (OR:2.54; 95%CI:1.67-3.85) were significantly (p<0.05) having high odds for coxiellosis. The multivariable logistic regression analysis of the animal level risk factors revealed that species and age were found to be significantly associated with coxiellosis. However, since the number of screened farms is limited; further research is needed with a higher number of animals to confirm the farm level odds ratio of risk factors. Quarantine and biosecurity measures including farm hygiene operations were observed to be inadequate and also the lack of awareness about coxiellosis among the farm workers. In absence of vaccination program for coxiellosis in India, robust surveillance, farm biosecurity measures and the awareness for the disease among risk groups can play an important role in the disease prevention and subsequent transmission of the pathogen.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Enfermedades de los Bovinos/sangre , Coxiella burnetii/genética , Fiebre Q/sangre , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/microbiología , Coxiella burnetii/patogenicidad , Ensayo de Inmunoadsorción Enzimática , Agricultores , Femenino , Humanos , India/epidemiología , Leche/microbiología , Reacción en Cadena de la Polimerasa , Fiebre Q/genética , Fiebre Q/microbiología , Zoonosis/sangre , Zoonosis/genética , Zoonosis/microbiología
11.
Ann Agric Environ Med ; 27(3): 356-360, 2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32955214

RESUMEN

OBJECTIVES: The aim of this study is to evaluate the seroprevalence of antibodies of Borrelia burgdorferi sensu lato (Bbsl) and Leptospira interrogans sensu lato (Lisl) and their possible concurrence in domestic cats living in variable conditions in South Moravia in the district of Brno and its environs. Additional objectives were to discover possible differences in seroprevalence between groups of cats living in different living conditions, and to determine the spectrum of Leptospira serogroups in cats in the same places. MATERIAL AND METHODS: A total of 360 blood sera from domestic cats of 3 different sets were collected during the period 2013-2015. All samples were examined using ELISA for the detection of IgM and IgG antibodies against Bbsl, and the microscopic agglutination test (MAT) for the detection of antibodies against 8 serogroups of Lisl. RESULTS: The ELISA method determined 15.8%, 4.8% and 10.3% IgM anti-Borrelia antibodies in the patient group, shelter cats and street cats, respectively. IgG anti-Borrelia antibodies were found in 6.2%, 9.5%, 5.2%, respectively. Antibodies specific for 5 Leptospira serogroups were detected by the use of MAT in 8.8%, 9.5% and 10.3% of cats from the investigated groups. The total positivity of all examined cats for anti-Borrelia antibodies was 18.0% and for anti-Leptospira - 9.2%. CONCLUSIONS: Cats can be infected with both Bbsl and Lisl. The obtained results are exclusive to the city of Brno and its environs, and are comparable to the limited previous studies. There is a need for further studies of clinical signs of both infections and the possible transmission of Leptospira by ticks.


Asunto(s)
Grupo Borrelia Burgdorferi/aislamiento & purificación , Enfermedades de los Gatos/epidemiología , Leptospira interrogans/aislamiento & purificación , Leptospirosis/veterinaria , Enfermedad de Lyme/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Enfermedades de los Gatos/microbiología , Gatos , República Checa/epidemiología , Leptospirosis/epidemiología , Leptospirosis/microbiología , Enfermedad de Lyme/epidemiología , Enfermedad de Lyme/microbiología , Prevalencia , Estudios Seroepidemiológicos
12.
PLoS Negl Trop Dis ; 14(9): e0008647, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32877398

RESUMEN

The transmission of trachoma, caused by repeat infections with Chlamydia trachomatis, and many enteropathogens are linked to water quantity. We hypothesized that children living further from a water source would have higher exposure to C. trachomatis and enteric pathogens as determined by antibody responses. We used a multiplex bead assay to measure IgG antibody responses to C. trachomatis, Giardia intestinalis, Cryptosporidium parvum, Entamoeba histolytica, Salmonella enterica, Campylobacter jejuni, enterotoxigenic Escherichia coli (ETEC) and Vibrio cholerae in eluted dried blood spots collected from 2267 children ages 0-9 years in 40 communities in rural Ethiopia in 2016. Linear distance from the child's house to the nearest water source was calculated. We derived seroprevalence cutoffs using external negative control populations, if available, or by fitting finite mixture models. We used targeted maximum likelihood estimation to estimate differences in seroprevalence according to distance to the nearest water source. Seroprevalence among 1-9-year-olds was 43% for C. trachomatis, 28% for S. enterica, 70% for E. histolytica, 54% for G. intestinalis, 96% for C. jejuni, 76% for ETEC and 94% for C. parvum. Seroprevalence increased with age for all pathogens. Median distance to the nearest water source was 473 meters (IQR 268, 719). Children living furthest from a water source had a 12% (95% CI: 2.6, 21.6) higher seroprevalence of S. enterica and a 12.7% (95% CI: 2.9, 22.6) higher seroprevalence of G. intestinalis compared to children living nearest. Seroprevalence for C. trachomatis and enteropathogens was high, with marked increases for most enteropathogens in the first two years of life. Children living further from a water source had higher seroprevalence of S. enterica and G. intestinalis indicating that improving access to water in the Ethiopia's Amhara region may reduce exposure to these enteropathogens in young children.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Anticuerpos Antiprotozoarios/sangre , Infecciones por Chlamydia/microbiología , Chlamydia trachomatis/inmunología , Criptosporidiosis/sangre , Cryptosporidium/inmunología , Entamebiasis/sangre , Giardiasis/sangre , Niño , Preescolar , Infecciones por Chlamydia/sangre , Infecciones por Chlamydia/epidemiología , Chlamydia trachomatis/genética , Estudios Transversales , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , Cryptosporidium/genética , Entamoeba histolytica/genética , Entamoeba histolytica/inmunología , Entamebiasis/epidemiología , Entamebiasis/parasitología , Etiopía/epidemiología , Femenino , Agua Dulce/parasitología , Giardia lamblia/genética , Giardia lamblia/inmunología , Giardiasis/epidemiología , Giardiasis/parasitología , Humanos , Masculino , Estudios Seroepidemiológicos
13.
PLoS One ; 15(8): e0238202, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32846428

RESUMEN

The immune system of ectotherms, particularly non-avian reptiles, remains poorly characterized regarding the genes involved in immune function, and their function in wild populations. We used RNA-Seq to explore the systemic response of Mojave desert tortoise (Gopherus agassizii) gene expression to three levels of Mycoplasma infection to better understand the host response to this bacterial pathogen. We found over an order of magnitude more genes differentially expressed between male and female tortoises (1,037 genes) than differentially expressed among immune groups (40 genes). There were 8 genes differentially expressed among both variables that can be considered sex-biased immune genes in this tortoise. Among experimental immune groups we find enriched GO biological processes for cysteine catabolism, regulation of type 1 interferon production, and regulation of cytokine production involved in immune response. Sex-biased transcription involves iron ion transport, iron ion homeostasis, and regulation of interferon-beta production to be enriched. More detailed work is needed to assess the seasonal response of the candidate genes found here. How seasonal fluctuation of testosterone and corticosterone modulate the immunosuppression of males and their susceptibility to Mycoplasma infection also warrants further investigation, as well as the importance of iron in the immune function and sex-biased differences of this species. Finally, future transcriptional studies should avoid drawing blood from tortoises via subcarapacial venipuncture as the variable aspiration of lymphatic fluid will confound the differential expression of genes.


Asunto(s)
Infecciones por Mycoplasma/inmunología , Infecciones por Mycoplasma/veterinaria , Mycoplasma/inmunología , Tortugas/genética , Tortugas/inmunología , Animales , Anticuerpos Antibacterianos/sangre , California , Citocinas/genética , Citocinas/inmunología , Clima Desértico , Femenino , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Interferón Tipo I/genética , Interferón Tipo I/inmunología , Transporte Iónico/genética , Hierro/metabolismo , Masculino , Infecciones por Mycoplasma/microbiología , Nevada , Factores Sexuales
14.
Rev Bras Parasitol Vet ; 29(3): e005320, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32785527

RESUMEN

Tick-borne rickettsial pathogens (TBRP) are important causes of infections in both dogs and humans. Dogs play an important role as a biological host for several tick species and can serve as sentinels for rickettsial infections. Our aim was to determine the presence of TBRP in dogs and in dog-associated ticks and their potential risk to human diseases in Medellin, Colombia. DNA for E. canis (16S rRNA and dsb) and A. platys (groEl) was detected in 17.6% (53/300) and 2.6% (8/300) of dogs, respectively. Antibodies against Ehrlichia spp. 82 (27.3%) and Anaplasma spp. 8 (2.6%) were detected in dogs. Antibody reactivity against both agents were found in 16 dogs (5.3%). Eight dogs showed antibody for Rickettsia spp. with titers that suggest 3 of them had a probable exposure to R. parkeri. Rhipicephalus sanguineus s.l. (178/193) was the main tick in dogs, followed by R. microplus (15/193). The minimum infection rates (MIR) in R. sanguineus were 11.8% for E. canis and 3.4% for A. platys. E. canis and A. platys are the main TBRP infecting dogs and ticks and R. sanguineus s.l. is likely involved in the transmission of both agents. Interestingly, we found serological evidence of exposure in dogs for spotted fever group rickettsiae.


Asunto(s)
Anaplasmosis , Enfermedades de los Perros , Ehrlichiosis , Rhipicephalus sanguineus , Infecciones por Rickettsia , Enfermedades por Picaduras de Garrapatas , Anaplasma/genética , Anaplasmosis/epidemiología , Anaplasmosis/microbiología , Animales , Anticuerpos Antibacterianos/sangre , Colombia/epidemiología , Enfermedades de los Perros/microbiología , Enfermedades de los Perros/parasitología , Perros , Ehrlichia/genética , Ehrlichiosis/epidemiología , Ehrlichiosis/microbiología , Ehrlichiosis/veterinaria , Humanos , ARN Ribosómico 16S , Rhipicephalus sanguineus/microbiología , Rickettsia/genética , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Infecciones por Rickettsia/veterinaria , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/veterinaria
15.
Vet J ; 262: 105504, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32792093

RESUMEN

Lyme disease (LD) is a tick-transmitted disease caused by Borreliella burgdorferi (Bb). Temporal studies of maternal antibody (Ab) profiles in Bb infected pregnant dogs and their pups have not been conducted. In this study, Ab profiles of a client-owned Bb C6 Ab positive Rottweiler and her nine pups were assessed. The dam presented with lameness 12 days prior to parturition and was C6 Ab positive with a Quant C6 Ab concentration of 237U/mL. Treatment with amoxicillin was initiated and 11 days later nine pups were delivered. Screening of the sera from the dam and pups against Bb cell lysates and a panel of antigens revealed similar immunoreactivity profiles. While antigen-specific IgG and IgM reactivity persisted in the dam for at least 7 months, a rapid decline in IgG specific for BBA36, BBK53, BB0238, BBA73 and outer surface protein (Osp) E in the pups occurred between days 29 and 52 post-parturition. In contrast, Ab specific for DbpA and the diagnostic antigens VlsE (C6) and OspF, remained elevated in the pups. Sera from the dam displayed potent complement-dependent bactericidal activity against Bb. Sera from the pups was also bactericidal but primarily through a complement-independent mechanism. Lastly, single dose vaccination of the dam at day 51 post-parturition with a LD subunit vaccine consisting of OspA and an OspC chimeritope triggered a broad anti-OspC Ab response indicative of an anamnestic response. Although this study focused on a single case, these findings add to our knowledge of maternal Ab profiles and will aid the interpretation of serological assays in pups delivered by a Bb C6 Ab positive dog.


Asunto(s)
Borrelia burgdorferi/inmunología , Enfermedades de los Perros/diagnóstico , Vacunas contra Enfermedad de Lyme/inmunología , Enfermedad de Lyme/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Enfermedades de los Perros/tratamiento farmacológico , Enfermedades de los Perros/inmunología , Perros , Femenino , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/inmunología , Ontario , Vacunación/veterinaria
16.
PLoS One ; 15(8): e0237185, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32760103

RESUMEN

Several cohort studies have shown that periodontal disease is associated with an increased risk for stroke. However, it remains unclear whether serum antibody titers for a specific periodontal pathogen are associated with outcome after ischemic stroke, and which kinds of pathogens are associated with ischemic stroke. We examined the relationship between serum IgG titers to periodontal pathogens and outcome in ischemic stroke patients. A total of 445 patients with acute ischemic stroke (194 female [44.0%], mean age 71.9±12.3 years) were registered in this study. Serum IgG titers to 9 periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Prevotella nigrescens, Fusobacterium nucleatum, Treponema denticola, Tannerella forsythensis, Campylobacter rectus, Eikenella corrodens) were evaluated using the enzyme-linked immunosorbent assay (ELISA) method. An unfavorable outcome was defined as a 3 or higher on the modified Rankin Scale. The proportion of patients with unfavorable outcome was 25.4% (113 patients). Based on multivariate logistic regression analysis, numbers of IgG antibodies positive for periodontal pathogens (odds ratio 1.20, 95% CI 1.02-1.41, p = 0.03) were independent predictors of unfavorable outcome in ischemic stroke patients.


Asunto(s)
Periodontitis Agresiva/epidemiología , Anticuerpos Antibacterianos/sangre , Isquemia Encefálica/epidemiología , Inmunoglobulina G/sangre , Accidente Cerebrovascular/epidemiología , Anciano , Anciano de 80 o más Años , Periodontitis Agresiva/sangre , Isquemia Encefálica/microbiología , Isquemia Encefálica/terapia , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Serológicas/estadística & datos numéricos , Accidente Cerebrovascular/microbiología , Accidente Cerebrovascular/terapia , Resultado del Tratamiento
17.
PLoS One ; 15(8): e0237062, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32760105

RESUMEN

Nutritional status contributes to the regulation of immune responses against pathogens, and malnutrition has been considered as a risk factor for tuberculosis (TB). Mycobacterium tuberculosis (Mtb), the causative agent of TB, can modulate host lipid metabolism and induce lipid accumulation in macrophages, where the bacilli adopt a dormant phenotype. In addition, serum lipid components play dual roles in the regulation of and protection from Mtb infection. We analyzed the relationship between nutritional status and the humoral immune response in TB patients. We found that serum HDL levels are positively correlated with the serum IgA specific for Mtb antigens. Analysis of the relationship between serum nutritional parameters and clinical parameters in TB patients showed that serum albumin and CRP levels were negatively correlated before treatment. We also observed reduced serum LDL levels in TB patients following treatment. These findings may provide insight into the role of serum lipids in host immune responses against Mtb infection. Furthermore, improving the nutritional status may enhance vaccination efficacy.


Asunto(s)
Inmunidad Humoral , Mycobacterium tuberculosis/inmunología , Estado Nutricional/inmunología , Tuberculosis Pulmonar/inmunología , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Proteína C-Reactiva/metabolismo , Progresión de la Enfermedad , Femenino , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Albúmina Sérica Humana/metabolismo , Vacunas contra la Tuberculosis/inmunología , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/tratamiento farmacológico
18.
Am J Trop Med Hyg ; 103(3): 1032-1038, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32720632

RESUMEN

Transcutaneous vaccination can induce both mucosal and systemic immune responses. However, there are few data on anti-polysaccharide responses following transcutaneous vaccination of polysaccharides, despite the role that anti-polysaccharide responses play in protecting against intestinal mucosal and respiratory pathogens. Whether transcutaneous vaccination with a conjugate polysaccharide vaccine would be able to induce memory responses is also unknown. To address this, we transcutaneously vaccinated mice with virulence antigen (Vi) polysaccharide of Salmonella enterica serovar Typhi (the cause of typhoid fever), either in unconjugated or conjugated form (the latter as a Vi-DT conjugate). We also assessed the ability of the immunoadjuvant cholera toxin to impact responses following vaccination. We found that presenting Vi in a conjugate versus nonconjugate form transcutaneously resulted in comparable serum IgG responses but higher serum and lamina propria lymphocyte IgA anti-Vi responses, as well as increased IgG memory responses. The addition of immunoadjuvant did not further increase these responses; however, it boosted fecal IgA and serum IgG anti-Vi responses. Our results suggest that transcutaneous vaccination of a conjugate vaccine can induce systemic as well as enhanced mucosal and memory B-cell anti-polysaccharide responses.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Inmunidad Humoral/efectos de los fármacos , Inmunidad Mucosa/efectos de los fármacos , Salmonella typhi/inmunología , Fiebre Tifoidea/prevención & control , Vacunas Tifoides-Paratifoides/administración & dosificación , Vacunación/métodos , Administración Cutánea , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Esquemas de Inmunización , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Memoria Inmunológica/efectos de los fármacos , Ratones , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/inmunología , Salmonella typhi/efectos de los fármacos , Salmonella typhi/patogenicidad , Fiebre Tifoidea/inmunología , Fiebre Tifoidea/microbiología , Vacunas Tifoides-Paratifoides/biosíntesis , Vacunas Conjugadas
19.
Arch Dis Child ; 105(9): 825-829, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32601082

RESUMEN

OBJECTIVE: Despite substantial variation of streptococcal antibody titres among global populations, there is no data on normal values in sub-Saharan Africa. The objective of this study was to establish normal values for antistreptolysin O (ASO) and antideoxyribonuclease B (ADB) antibodies in Uganda. DESIGN: This was an observational cross-sectional study. SETTING: This study was conducted at Mulago National Referral Hospital, which is located in the capital city, Kampala, and includes the Uganda Heart Institute. PATIENTS: Participants (aged 0-50 years) were recruited. Of 428 participants, 22 were excluded from analysis, and 183 (44.4%) of the remaining were children aged 5-15 years. MAIN OUTCOME MEASURES: ASO was measured in-country by nephelometric technique. ADB samples were sent to Australia (PathWest) for analysis by enzyme inhibition assay: 80% upper limit values were established. RESULTS: The median ASO titre in this age group was 220 IU/mL, with the 80th percentile value of 389 IU/mL. The median ADB titre in this age group was 375 IU/mL, with the 80th percentile value of 568 IU/mL. CONCLUSIONS: The estimated Ugandan paediatric population standardised 80% upper-limit-of-normal ASO and ADB titres is higher than many global populations. Appropriateness of using population-specific antibody cutoffs is yet to be determined and has important implications for the sensitivity and specificity of rheumatic fever diagnosis.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Streptococcus pyogenes/inmunología , Adolescente , Adulto , Factores de Edad , Anticuerpos Antibacterianos/inmunología , Antiestreptolisina/inmunología , Niño , Preescolar , Estudios Transversales , Desoxirribonucleasas/inmunología , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Valores de Referencia , Infecciones Estreptocócicas/sangre , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/inmunología , Uganda/epidemiología , Adulto Joven
20.
Rev Bras Parasitol Vet ; 29(2): e021419, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32609243

RESUMEN

The purpose of this study was to do a serological survey on three rickettsial species: Rickettsia rickettsii and Rickettsia parkeri, two species of the spotted fever group (SFG) that are considered to be great importance for public health; and Rickettsia bellii, a species of unknown pathogenicity that infects a variety of human-biting ticks. Serum samples from 273 dogs were tested using the indirect immunofluorescence assay (IFA). A total of 52 samples (19.04%) were seropositive for at least one of the three Rickettsia spp. antigens. Thirty-eight (73.07%), twelve (23.07%) and one (1.92%) of these dogs showed homologous reactions to R. bellii, R. rickettsii and R. parkeri, respectively. Our results showed that the seroprevalence of Rickettsia spp. was relatively low. However, the positive serological tests indicated that these dogs had become infected by these agents at some point in their lives. Lastly, our study adds to the previous knowledge on the epidemiology of rickettsiosis in the state of Goiás by doing the first record of detection of anti-R. rickettsii, R. parkeri and R. bellii antibodies by IFA among dogs, thus indicating that these agents may be circulating in the dog population analyzed.


Asunto(s)
Enfermedades de los Perros , Infecciones por Rickettsia , Rickettsia , Rickettsiosis Exantemáticas/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Brasil/epidemiología , Enfermedades de los Perros/sangre , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros , Humanos , Rickettsia/fisiología , Infecciones por Rickettsia/sangre , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/veterinaria , Estudios Seroepidemiológicos
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