Correlation between different clinical manifestations and changes of blood indexes in canine leishmaniasis / 中华地方病学杂志

Objective:To study the main blood parameters of Leishmania-infected dogs with different clinical symptoms in the high incidence area of visceral leishmaniasis in Gansu Province, and to provide scientific basis for early diagnosis and monitoring of canine leishmaniasis. Methods:In May 2019, Wenxian County of Longnan City and Diebu County of Gannan Tibetan Autonomous Prefecture, the historical endemic areas of visceral leishmaniasis in Gansu Province, were selected as the investigation sites, and 40 dogs with positive Leishmania DNA were investigated. According to their clinical symptoms, they were divided into three groups: asymptomatic ( n = 17), minimally symptomatic ( n = 12) and symptomatic ( n = 11). At the same time, 10 healthy dogs were selected as controls. Major blood indexes were detected by an automatic animal blood five-classification cell analyzer. Results:Compared with the control group, the number of red blood cells, hemoglobin content, hematocrit, and the number of lymphocytes, monocytes and eosinophils in the asymptomatic, minimally symptomatic and symptomatic groups were decreased ( P < 0.05), while the number of white blood cells and neutrophils in minimally symptomatic and symptomatic groups were decreased ( P < 0.05). The above blood indexes were lower in the symptomatic group than those in the asymptomatic group. The number of red blood cells (control group vs symptomatic group) decreased from (6.82 ± 0.05) × 10 12/L to (4.19 ± 0.08) × 10 12/L, hemoglobin content decreased from (15.84 ± 0.74) g/L to (9.65 ± 0.18) g/L, hematocrit decreased from (46.41 ± 0.95)% to (27.86 ± 0.42)%, the number of white blood cells decreased from (14.90 ± 0.22) × 10 9/L to (10.23 ± 0.24) × 10 9/L, the number of neutrophils decreased from (7.25 ± 0.18) × 10 9/L to (6.18 ± 0.11) × 10 9/L, the number of lymphocytes decreased from (2.80 ± 0.07) × 10 9/L to (1.64 ± 0.06) × 10 9/L, the number of monocytes decreased from (1.13 ± 0.01) × 10 9/L to (0.53 ± 0.02) × 10 9/L, and the number of eosinophils decreased from (1.70 ± 0.06) × 10 9/L to (0.71 ± 0.03) × 10 9/L. Conclusion:Different clinical symptoms of Leishmania-infected dogs have different blood test results.

Clinical observation on Yi Jin Jing(Sinew-transforming Qigong Exercises)in improving anxiety for asymptomatic patients with COVID-19 infection during quarantine / 针灸推拿医学（英文版）

Objective:To observe the effect of Yi Jin Jing(Sinew-transforming Qigong Exercises)intervention on anxiety in asymptomatic patients with Corona Virus Disease 2019(COVID-19)infection during quarantine.Methods:A total of 160 asymptomatic patients with COVID-19 infection were stratified by gender and divided into an observation group and a control group by the stratified randomization method,with 80 cases in each group.The control group was given basic nursing in the cabin,and the observation group was given additional Yi Jin Jing exercises once a day,20 min each time,and trained continuously until 1 d before leaving the cabin.The Hamilton anxiety scale(HAMA)score was compared between the two groups.Results:A total of 154 cases were included for data analysis in this study,including 74 cases in the observation group and 80 cases in the control group.After intervention,the HAMA scores in both groups increased(P<0.05),while the score in the observation group was lower than that in the control group(P<0.05).In the control group,the HAMA score of females after intervention was higher than that of males.The scores of mental anxiety and somatic anxiety in both groups were higher than those before intervention,while the score of mental anxiety in the observation group was significantly lower than that in the control(P<0.05).However,there was no statistical difference in the somatic score between the two groups(P>0.05).Conclusion:Patients with COVID-19 infection will get anxious during quarantine.Yi Jin Jing exercise can effectively reduce the aggravation of anxiety in asymptomatic patients with COVID-19 infection during concentrated quarantine.

Necessity of asymptomatic bacteriuria screening during pregnancy / 中华围产医学杂志

Asymptomatic bacteriuria (ASB) refers to the presence of one or more species of bacteria in an individual's urine without the symptoms of a urinary tract infection. Previous studies have shown that untreated ASB during pregnancy is associated with adverse pregnancy outcomes. Many international guidelines recommend a single screen-and-treat approach to ASB during pregnancy. Still, this approach has not been proven favorable to pregnancy outcomes in low-risk populations by recent studies. ASB screening is not a routine obstetric examination in clinical practice in China. Given this, this article will review the evidence of ASB screening during pregnancy and analyze the recommendations and existing problems in the guidelines from various academic organizations. Clinical studies should be carried out according to the situation in the region, and the basic risks and treatment benefits of ASB in pregnancy should be analyzed in combination with specific data to establish a proper screening and treatment plan for ASB during pregnancy. Screening for ASB is recommended for pregnant women with high-risk factors at this stage.

Assessing reservoir host status in leishmaniasis with special reference to the infectiousness of Leishmania (Viannia) braziliensis infections in wild rodents

ABSTRACT Molecular methods have been responsible for a notable increase in the detection of Leishmaniinae infections in wild animals. Determining their infectiousness is of paramount importance in evaluating their epidemiological significance. One of the most efficient ways of determining infectiousness for vector borne diseases is xenodiagnosis with the appropriate vector. However, this is logistically very difficult to accomplish in the field, and an ideal solution is to find a molecular surrogate for xenodiagnosis. In this review we discuss different approaches to the problem by focusing on the infectiousness of Leishmania (Viannia) braziliensis in rodents under laboratory and field conditions. Comparisons with similar studies for other Leishmania species emphasizes that there are pivotal differences in the infectiousness and the importance of asymptomatic infections in different hosts. Potentially the most promising surrogate is the real time quantitative PCR (qPCR). However, its success depends on choosing a tissue that relates to the vector's feeding location and the parasite's tissue tropism. This requires detailed knowledge of the infection of each species in its wild hosts. We conclude that for L. (V.) braziliensis infections in wild rodents the tissue of choice for a molecular xenodiagnostic test, based on the qPCR is blood, providing that a significant number of samples must be examined.

Factores de riesgo asociados a infección de catéter de hemodiálisis en un centro de referencia

RESUMEN Introducción: la infección asociada a catéter de hemodiálisis es una causa importante de morbimortalidad en los pacientes que requieren hemodiálisis de manera permanente, elevando el riesgo de mortalidad 2 veces más de los que no lo tienen. Por esto resulta imprescindible determinar los factores predisponentes a adquirir esta infección. Objetivos: determinar los factores de riesgo asociados a la infección del catéter de hemodiálisis de los pacientes en el Hospital Nacional de Itauguá. Métodos: se realizó un estudio observacional de casos y controles de 104 pacientes, 52 pacientes como casos y 52 como controles. Resultados: se analizaron las siguientes variables cualitativas como factores de riesgo: desconocimiento del cuidado del catéter (OR: 9,66; p: 0,05), hipertensión arterial (OR: 1,17; p: >0,05) ausencia de infección previa (OR: 2,25; p: <0,05), procedencia rural (OR: 2,67; p: <0,05), ubicación del catéter femoral (OR: 6,51; p: <0,05), colonización con Staphylococcus aureus (OR: 15,6; p: <0,05), curación única semanal (OR: 37,40; p: <0,05) y escolaridad primaria (OR: 2,93; p: <0,05). En cuanto a las variables cuantitativas se analizaron la edad (p: <0,05), tiempo de instalación del catéter (p: <0,05) y tiempo de evolución de la hemodiálisis (p: 0,2) Conclusión: se asociaron de manera significativa a la infección de catéter de hemodiálisis el desconocimiento del cuidado del catéter, la ausencia de turno fijo trisemanal, la procedencia rural, la colonización con Staphylococcus aureus, la curación una vez por semana del catéter y la escolaridad primaria, la edad mayor a 51 años y la instalación reciente del catéter.

ABSTRACT Introduction: Hemodialysis catheter-associated infection is an important cause of morbidity and mortality in patients who require permanent hemodialysis, raising the risk of mortality two times more than those who do not. For this reason, it is essential to determine the predisposing factors to acquire this infection. Objectives: To determine the risk factors associated with hemodialysis catheter infection in patients at the Hospital Nacional of Itauguá. Methods: An observational case-control study of 104 patients was carried out, 52 patients as cases and 52 as controls. Results: The following qualitative variables were analyzed as risk factors: lack of knowledge of catheter care (OR: 9.66; p: 0.05), arterial hypertension (OR: 1.17; p: >0.05), absence of previous infection (OR: 2.25; p: <0, 05), rural origin (OR: 2.67; p: <0.05), femoral catheter location (OR: 6.51; p: <0.05), colonization with Staphylococcus aureus (OR: 15.6; p: <0.05), single weekly cure (OR: 37.40; p: <0.05) and primary education (OR: 2.93; p: <0.05). Regarding the quantitative variables, age (p: <0.05), time of catheter installation (p: <0.05) and time of evolution of hemodialysis (p: 0,2) were analyzed. Conclusion: Ignorance of catheter care, absence of three-week fixed shift, rural origin, colonization with Staphylococcus aureus, catheter healing once a week, primary education, age over 51 years and recent catheter installation were significantly associated with hemodialysis catheter infection.

Clinically silent Plasmodium vivax infections in native Amazonians of northwestern Brazil: acquired immunity or low parasite virulence?

BACKGROUND Malaria remains common among native Amazonians, challenging Brazil′s elimination efforts. OBJECTIVES We examined the epidemiology of malaria in riverine populations of the country′s main hotspot - the upper Juruá Valley in Acre state, close to the Brazil-Peru border, where Plasmodium vivax accounts for > 80% of cases. METHODS Participants (n = 262) from 10 villages along the Azul River were screened for malaria parasites by microscopy and genus-specific, cytochrome b (cytb) gene-based polymerase chain reaction. Positive samples were further tested with quantitative TaqMan assays targeting P. vivax- and P. falciparum-specific cytb domains. We used multiple logistic regression analysis to identify independent correlates of P. vivax infection. FINDINGS Microscopy detected only one P. vivax and two P. falciparum infections. TaqMan assays detected 33 P. vivax infections (prevalence, 11.1%), 78.1% of which asymptomatic, with a median parasitaemia of 34/mL. Increasing age, male sex and use of insecticide-treated bed nets were significant predictors of elevated P. vivax malaria risk. Children and adults were similarly likely to remain asymptomatic once infected. MAIN CONCLUSIONS Our findings are at odds with the hypothesis of age-related clinical immunity in native Amazonians. The low virulence of local parasites is suggested as an alternative explanation for subclinical infections in isolated populations.

An algorithm based on molecular protocols to improve the detection of Plasmodium in autochthonous malarial areas in the Atlantic Forest biome

ABSTRACT Malaria is the most important vector-borne disease in the world and a challenge for control programs. In Brazil, 99% of cases occur in the Amazon region. In the extra-Amazonian region, a non-endemic area, epidemiological surveillance focuses on imported malaria and on autochthonous outbreaks, including cases with mild symptoms and low parasitemia acquired in the Atlantic Forest biome. In this scenario, cases are likely to be underreported, since submicroscopic parasitemias are not detected by thick blood smear, considered the reference test. Molecular tests are more sensitive, detecting asymptomatic individuals and mixed infections. The aim of this study was to propose a more efficient alternative to detect asymptomatic individuals living in areas of low malaria endemicity, as they are reservoirs of Plasmodium that maintain transmission locally. In total, 955 blood samples from residents of 16 municipalities with autochthonous malaria outbreaks in the Sao Paulo State were analyzed; 371 samples were collected in EDTA tubes and 584 in filter paper. All samples were initially screened by a genus-specific qPCR targeting ssrRNA genes (limit of detection of 1 parasite/µL). Then, positive samples were subjected to a nested PCR targeting ssrRNA and dihydrofolate reductase-thymidylate synthase genes (limit of detection of 10 parasites/µL) to determine Plasmodium species. The results showed a statistically significant difference (K = 0.049; p < 0.0001) between microscopy positivity (6.9%) and qPCR (22.9%) for EDTA-blood samples. Conversely, for samples collected in filter paper, no statistical difference was observed, with 2.6% positivity by thick blood smear and 3.1% for qPCR (K = 0.036; p = 0.7). Samples positive by qPCR were assayed by a species-specific nested PCR that was in turn positive in 26% of samples (16 P. vivax and 4 P. malariae ). The results showed that molecular protocols applied to blood samples from residents in areas with autochthonous transmission of malaria were useful to detect asymptomatic patients who act as a source of transmission. The results showed that the genus-specific qPCR was useful for screening positives, with the subsequent identification of species by nested PCR. Additional improvements, such as standardization of blood plotting on filter paper and a more sensitive protocol for species determination, are essential. The qPCR-based algorithm for screening positives followed by nested PCR will contribute to more efficient control of malaria transmission, offering faster and more sensitive tools to detect asymptomatic Plasmodium reservoirs.

Epidemiological characteristics and transmission chain of COVID-19 in Harbin in January 2021 / 中华地方病学杂志

Objective:To observe the epidemiological characteristics and transmission chain of COVID-19 in Harbin, and to provide epidemiological evidence for improving the COVID-19 preventive measures and optimizing prevention and control strategies.Methods:The epidemic situation of COVID-19 in Harbin in January 2021 was analyzed by using the Infectious Disease Report Information Management System and the Public Health Emergency Management Information System of the China Disease Prevention and Control Information System, the epidemic situation information publicly released by the Heilongjiang Provincial Health Commission, and the epidemiological report of Heilongjiang Province Certer for Disease Control and Prevention and Harbin Center for Disease Control and Prevention. The main transmission chains were sorted out through combination of epidemiological field investigation, serological testing, gene sequencing, big data and other means.Results:From January 12 to February 4, 2021, 295 cases of COVID-19 infection (including confirmed cases and asymptomatic infections) were reported in Harbin, which affected 6 districts of Harbin and were concentrated in 41 of the 274 townships in the city. The sex ratio of male to female was 1.00∶1.12 (139∶156); the age ranged from 1 to 86 years old, and the median age was 45 years old. The proportion of confirmed cases and asymptomatic infection was 1.00 ∶ 1.02 (146 ∶ 149), and there was a significant difference in the distribution of different ages between them ( P = 0.042). The cases were mainly found through the health screening of the centralized isolation personnel (178 cases, 60.3%). Other detection methods included active screening (87 cases, 29.5%), screening of the home isolation personnel (26 cases, 8.8%), and medical treatment in medical institutions (4 cases, 1.4%). The main transmission chain of the outbreak was the case associated with a food processing enterprise, with a total of 259 cases, accounting for 87.8% of the total cases. The gene sequencing results showed that the case sequence was homologous with that of Wangkui County, Suihua City, Heilongjiang Province. Conclusions:A food processing enterprise is involved in the main transmission chain, which indicates that the epidemic prevention and control measures needs to be further optimized. Specifically, the supervision and management of food processing enterprises, cold chain storage companies and other enterprises should be strengthened. High attention should be paid to the hidden dangers of COVID-19 in large and medium sized enterprises with hermetic space in Harbin.

SARS-CoV-2 y RT-PCR en pacientes asintomáticos: resultados de una cohorte de trabajadores del Aeropuerto Internacional El Dorado de Bogotá, 2020 / SARS-CoV-2 and RT-PCR in asymptomatic patients: Results of a cohort of workers at El Dorado International Airport in Bogotá, 2020

Introducción. La pandemia de COVID-19 ha ocasionado cerca de 25 millones de casos en el mundo. Se ha descrito que los pacientes asintomáticos pueden ser fuentes de transmisión. Sin embargo, es difícil detectarlos y no es claro su papel en la dinámica de transmisión del virus, lo que obstaculiza la implementación de estrategias para la prevención. Objetivo. Describir el comportamiento de la infección asintomática por SARS-CoV-2 en una cohorte de trabajadores del Aeropuerto Internacional El Dorado "Luis Carlos Galán Sarmiento" de Bogotá, Colombia. Materiales y métodos. Se diseñó una cohorte prospectiva de trabajadores del Aeropuerto El Dorado. El seguimiento se inició en junio de 2020 con una encuesta a cada trabajador para caracterizar sus condiciones de salud y trabajo. Cada 21 días se tomó una muestra de hisopado nasofaríngeo para detectar la presencia del SARS-CoV-2 mediante reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Se analizó el comportamiento del umbral del ciclo (cycle threshold) de los genes ORFlab y N según el día de seguimiento. Resultados. En los primeros tres seguimientos de la cohorte se encontró una incidencia de la infección por SARS-CoV-2 del 16,51 %. La proporción de contactos positivos fue del 14,08 %. La mediana del umbral del ciclo fue de 33,53. Conclusión. Se determinaron las características de la infección asintomática por el SARS-CoV-2 en una cohorte de trabajadores. La detección de infectados asintomáticos sigue siendo un reto para los sistemas de vigilancia epidemiológica.

Introduction: The 2019 coronavirus pandemic (COVID-19) has caused around 25 million cases worldwide. Asymptomatic patients have been described as potential sources of transmission. However, there are difficulties to detect them and to establish their role in the dynamics of virus transmission, which hinders the implementation of prevention strategies. Objective: To describe the behavior of asymptomatic SARS-CoV-2 virus infection in a cohort of workers at the El Dorado "Luis Carlos Galán Sarmiento" International Airport in Bogotá, Colombia. Materials and methods: A prospective cohort of 212 workers from the El Dorado airport was designed. The follow-up began in June, 2020. A survey was used to characterize health and work conditions. Every 21 day, a nasopharyngeal swab was taken to identify the presence of SARS-CoV-2 using RT-PCR. We analyzed the behavior of the cycle threshold (ORFlab and N genes) according to the day of follow-up. Results: In the first three follow-ups of the cohort, we found an incidence of SARS-CoV-2 infection of 16.51%. The proportion of positive contacts was 14.08%. The median threshold for cycle threshold was 33.53. Conclusion: We characterized the asymptomatic SARS-CoV-2 infection in a cohort of workers. The identification of asymptomatic infected persons continues to be a challenge for epidemiological surveillance systems.

Susceptibilidad antibiótica de Staphylococcus aureus de aislados nasales en estudiantes del norte de Perú / Antibiotic susceptibility of Staphylococcus aureus from nasal isolates in students from northern Peru

Objetivos: determinar el perfil de susceptibilidad antibiótica de Staphylococcus aureus, en estudiantes de Biología, Enfermería y Medicina de la Universidad Nacional Pedro Ruiz Gallo-Lambayeque. Métodos: Las muestras fueron recolectadas mediante hisopados nasales. Se realizó el aislamiento primario en Agar Manitol Salado, para la recuperación e identificación de Staphylococcus aureus de octubre 2015- marzo 2016. La prueba de susceptibilidad bacteriana se realizó la prueba de sensibilidad antimicrobiana por el método de disco de difusión. Resultados: se aislaron 43 cultivos positivos para Staphylococcus aureus, lo cual representó el 28,6%; siendo negativas 107 muestras, representando el 71,4%. Se determinó que, el 90,6% de las cepas fueron resistentes a Oxacilina, el 81,3 % a Sulfametoxazol - Trimetoprima, el 95,3 % a Penicilina, el 34,8% a Cefoxitina, siendo todas las cepas 100% sensibles a Imipenem y Vancomicina. La evaluación de la reacción cruzada dio como resultado que el 2.6% de las cepas presentaron resistencia a Ceftazidima, 12,8% a Azitromicina, el 15,4 % a Cefotaxima, y el 20,9% a Gentamicina; por el contario fueron 100% sensibles a Amikacina, Ciprofloxacino, Ceftriaxona y Cefuroxima. Conclusiones: El 28,6% del total de la población en estudio dio positiva para Staphylococcus aureus, el 90,6 % de las cepas de fueron resistentes a Oxacilina, siendo todas las cepas sensibles a Imipenem. La Escuela profesional de Ciencias Biológicas fue quien presentó mayor frecuencia de aislamientos de Staphylococcus aureus.

Objectives: To determine the antibiotic susceptibility profile of Staphylococcus aureus, in Biology, Nursing and Medicine students of the Pedro Ruiz Gallo-Lambayeque National University. Methods: Samples were collected by means of nasal swabs. Primary isolation was performed on Salt Mannitol Agar, for the recovery and identification of Staphylococcus aureus from October 2015 to March 2016. The bacterial susceptibility test was performed by the antimicrobial sensitivity test by the diffusion disc method. Results: 43 positive cultures were isolated for Staphylococcus aureus, which represented 28.6%; 107 samples were negative, representing 71.4%. It was determined that, 90.6% of the strains were resistant to Oxacillin, 81.3% to Sulfamethoxazole - Trimethoprim, 95.3% to Penicillin, 34.8% to Cefoxitin, being all strains 100% sensitive to Imipenem and Vancomycin. Evaluation of the cross reaction resulted in 2.6% of the strains showing resistance to Ceftazidime, 12.8% to Azithromycin, 15.4% to Cefotaxime, and 20.9% to Gentamicin; on the contrary they were 100% sensitive to Amikacin, Ciprofloxacin, Ceftriaxone and Cefuroxime. Conclusions: 28.6% of the total population in the study was positive for Staphylococcus aureus, 90.6% of the strains were resistant to Oxacillin, and all the strains were sensitive to Imipenem. The Professional School of Biological Sciences presented the highest frequency of Staphylococcus aureus isolates.

Malaria Prevalence in a Low Transmission Area, Jazan District of Southwestern Saudi Arabia

Detailed description of malaria in low transmission areas is crucial for elimination. The current study aimed to provide a comprehensive description for malaria transmission in Jazan, a low transmission district, southwestern Saudi Arabia. Patients at a tertiary care hospital were recruited in our study between August 2016 and September 2018. Malaria diagnosis was performed through a species-specific nested polymerase chain reaction (nested PCR), microscopy and Paramax-3™ rapid detection test (RDT). Malaria was detected in 30 patients by the PCR, with point prevalence of 10.9%. Of these malaria infections, 80% was imported, 26.6% was asymptomatic and 23.3% was sub-microscopic. Malaria was reported throughout the year, with February/March and September/October peaks. Infection was significantly more in males than in females (P=0.01). Likewise, infections were detected more in febrile than in non-febrile patients (P=0.01). Adult aged 15–24 years, fever and travel were identified as high-risk factors. Malaria was primarily attributed to Plasmodium falciparum mono-infections, followed by P. vivax mono-infections and lastly to falciparum/vivax mixed infections accounting 76.6%, 16.6%, and 6.6% of PCR-confirmed malaria cases, respectively. The nested PCR was superior to the smear microscopy (sensitivity 76.6%; specificity 100%) and the RDT (sensitivity 83.3%, specificity 94.2%). The overall percent agreement between microscopy and the RDT was 92.7% (kappa=0.63). High proportion of imported malaria including sub-microscopic and sub-patent cases were described. We suggest that incorporation of molecular tool into the conventional malaria diagnosis is beneficial in Jazan district.

Seroprevalencia y tasa de ataque clínica por chikungunya en Nicaragua, 2014-2015 / Chikungunya seroprevalence and clinical case rate in Nicaragua, 2014-2015

RESUMEN Objetivo Estimar la seroprevalencia, la tasa de ataque clínica y la proporción de infecciones subclínicas por chikungunya, Métodos Se realizó un estudio transversal en 39 sitios distribuidos en todo el territorio nacional de Nicaragua en octubre 2015. Se recopiló información demográfica y clínica a través de una encuesta personal. Se recolectaron muestras hemáticas para detectar la presencia de anticuerpos antivirus chikungunya utilizando el método de ELISA de inhibición desarrollado por el Centro Nacional de Diagnóstico y Referencia. Se utilizaron modelos lineales generalizados y modelos de multinivel de Poisson en el análisis de los resultados. Resultados Se enrolaron 11 722 participantes mayores de dos años de edad y se procesaron 11 280 muestras. En el nivel nacional, la seroprevalencia fue de 32,8% (IC95% [intervalo de confianza de 95%]: 31,9-33,6), con una tasa de ataque clínica de 26,5% (IC95%: 25,7-27,3) y una proporción de infecciones subclínicas de 19,1% (IC95%: 17,8-20,4). Se observó variabilidad en la seroprevalencia de los 39 sitios, y los que presentaron mayor índice de infestación por el vector mostraron una mayor seroprevalencia. A nivel individual, esta fue más elevada en los participantes mayores de 11 años. Conclusión Este es el primer estudio sobre la seroprevalencia de chikungunya en América Latina continental desde su introducción, en el que se determinaron la prevalencia a nivel nacional, la tasa de ataque clínico y la proporción de infecciones subclínicas. El modelo utilizado, con una amplia participación comunitaria y el rol rector del Ministerio de Salud de Nicaragua, puede constituir un ejemplo para la realización de estudios similares en la región.

ABSTRACT Objective Estimate seroprevalence, clinical case rate, and proportion of subclinical infections from chikungunya. Methods A cross-sectional study was conducted in October 2015 at 39 sites distributed across Nicaragua. Demographic and clinical information was compiled through a personal survey. Blood samples were collected to detect chikungunya antibodies using the ELISA inhibition method developed by Nicaragua's National Diagnostic and Reference Center. Results were analyzed using generalized linear models and multilevel Poisson models. Results A total of 11 722 participants aged >2 years were enrolled and 11 280 samples were processed. National seroprevalence was 32.8% (95% CI [95% confidence interval]: 31.9-33.6), with a clinical case rate of 26.5% (95% CI: 25.7-27.3) and a proportion of subclinical infections of 19.1% (95% CI: 17.8-20.4). Seroprevalence varied among the 39 sites and was greater at sites with higher vector infestation indices. Individually, seroprevalence was higher in participants aged >11 years. Conclusion Since its introduction, this is the first study on chikungunya seroprevalence in continental Latin America to determine national prevalence, clinical case rate, and proportion of subclinical infections. The study model, employing broad community participation and leadership by the Ministry of Health of Nicaragua, can be an example for conducting similar studies in the region.

Asymptomatic Pulmonary Tuberculosis in Infant

A 3-month-old asymptomatic infant presented with bilateral extensive consolidation of the lungs, which was diagnosed as pulmonary tuberculosis. Evaluation of the baby for tuberculosis was initiated because of a history of contact with a known tuberculosis patient. This case is interesting because the baby rarely showed symptoms during the whole course of the disease.

Asymptomatic Emphysematous Pyelonephritis Incidentally Detected with Computed Tomography in a Diabetic Hemodialysis Patient / 대한내과학회지

Emphysematous pyelonephritis (EPN) is a necrotizing infection of the kidney with gas formation that can be fatal if it is not detected and treated promptly. Typical manifestations are high fever, flank pain, and shock. It typically occurs in patients with diabetes and, although rarely reported, in hemodialysis (HD) patients with or without diabetes. Furthermore, asymptomatic EPN has not yet been reported in HD patients. Here, we report a case of asymptomatic EPN in a diabetic HD patient incidentally detected with follow-up abdominal computed tomography after resection of colon cancer.

Evaluation of anogenital human papillomavirus infection in asymptomatic men from Rio de Janeiro, Brazil

Infection by human papillomavirus (HPV) is among the most prevalent sexually transmitted diseases worldwide. However, there are still gaps in the knowledge regarding the natural history of HPV infection in men. This study aimed to determine the prevalence of HPV infection in penile swab samples, derived from a clinically asymptomatic male population. For this purpose, 261 samples were collected between January 2011 and July 2013 in different institutions in the city of Rio de Janeiro. These samples were collected from the glans, corona, frenulum and coronal sulcus of the penis. Viral identification was made through generic and type-specific Polymerase Chain Reaction, and Restriction Fragment Length Polymorphism techniques. Prevalence of HPV infection was 16.5% (43 subjects). The most prevalent HPV type was HPV6 (34.9%), followed by HPV16 (23.3%), HPV11 (16.3%), HPV45 (9.3%) and HPV58 (2.3%). Hence, infection was associated with low-risk oncogenic types in 53.7% of the studied individuals, while high-risk oncogenic types were detected in 46.3%. Statistically significant results were found for the group of men who have sex with men, the group who have active anal intercourse, and subjects that lacked circumcision. After adjustments, sexual behavior and lack of circumcision remained as independent risk factors for HPV infection. We believe that these results may contribute to a clearer view about the circulation of HPV in the general male population, as well as to the identification of risk factors associated with the epidemiology of HPV infection in our state.

Malaria in pregnant women living in areas of low transmission on the southeast Brazilian Coast: molecular diagnosis and humoural immunity profile

Studies on autochthonous malaria in low-transmission areas in Brazil have acquired epidemiological relevance because they suggest continued transmission in what remains of the Atlantic Forest. In the southeastern portion of the state of São Paulo, outbreaks in the municipality of Juquitiba have been the focus of studies on the prevalence of Plasmodium, including asymptomatic cases. Data on the occurrence of the disease or the presence of antiplasmodial antibodies in pregnant women from this region have not previously been described. Although Plasmodium falciparum in pregnant women has been widely addressed in the literature, the interaction of Plasmodium vivax and Plasmodium malariae with this cohort has been poorly explored to date. We monitored the circulation of Plasmodium in pregnant women in health facilities located in Juquitiba using thick blood film and molecular protocols, as well as immunological assays, to evaluate humoural immune parameters. Through real-time and nested polymerase chain reaction, P. vivax and P. malariae were detected for the first time in pregnant women, with a positivity of 5.6%. Immunoassays revealed the presence of IgG antibodies: 44% for ELISA-Pv, 38.4% for SD-Bioline-Pv and 18.4% for indirect immunofluorescence assay-Pm. The high prevalence of antibodies showed significant exposure of this population to Plasmodium. In regions with similar profiles, testing for a malaria diagnosis might be indicated in prenatal care.

Factors associated with asymptomatic infection in family members and neighbors of patients with visceral leishmaniasis / Fatores associados com a infecção assintomática em familiares e vizinhos de pacientes com leishmaniose visceral

This study analyzed factors associated with asymptomatic Leishmania chagasi infection in family members and neighbors of patients with visceral leishmaniasis (VL). A cross-sectional study was conducted with 361 individuals in the counties comprising Ilha de São Luís (São Luís Island) in Maranhão State, Brazil. The Montenegro skin test (MST) and serology by enzyme-linked immunosorbent assay (ELISA) were performed to detect infection. Odds ratios (OR) and prevalence ratios (PR) and their 95% confidence intervals (95%CI) were estimated by multilevel logistic regression and Poisson regression, respectively. The rates of positive reactions were 71.3% for MST and 9.7% for ELISA. The variable associated with infection according to MST was living in the same household as the index case (PR = 1.36; 95%CI: 1.03-1.78). According to ELISA, the statistically significant variables were: living in the county of Raposa (OR = 3.56; 95%CI: 1.24-10.19) and living in the same household as the index case (OR = 2.70; 95%CI: 1.19-6.08). Family members of individuals with LV are at increased risk of infection. Priority control measures should target these families.

Este estudo transversal analisou os fatores associados à infecção assintomática por Leishmania chagasi em familiares e vizinhos de pacientes com leishmaniose visceral (LV) e foi realizado com 361 indivíduos nos municípios que compõem a Ilha de São Luís, Maranhão, Brasil. Foram realizadas a Intradermorreação de Montenegro (IDRM) e a sorologia por Enzyme Linked Immunosorbent Assay (ELISA) para detectar a infecção. Razões de chances (RC) e razões de prevalências (RP) e seus intervalos de 95% de confiança (IC95%) foram estimadas por meio de regressão logística multinível e regressão de Poisson, respectivamente. A proporção de positivos foi de 71,3% para a IDRM e de 9,7% para o ELISA. A variável associada à infecção segundo a IDRM foi residir no domicílio do caso índice (RP = 1,36; IC95%: 1,03-1,78). Pelo ELISA, as variáveis com significância estatística foram: residir no Município de Raposa (RC = 3,56; IC95%: 1,24-10,19) e no domicílio do caso índice (RC = 2,70; IC95%: 1,19-6,08). Familiares de indivíduos com LV têm maior risco de infecção. Medidas de controle devem ser efetivadas e direcionadas prioritariamente a essas famílias.