Improved Performance of ELISA and Immunochromatographic Tests Using a New Chimeric A2-Based Protein for Human Visceral Leishmaniasis Diagnosis

Summary. Human visceral leishmaniasis (VL) is a major public health problem worldwide, leading to significant mortality rates if not properly treated and controlled. Precise identification of infected patients is essential to establish treatment and control measures. Although several VL serological diagnosis advances have been accomplished lately, mainly using recombinant antigens and immunochromatographic tests (ICTs), improvements may still be achieved using multiepitope chimeric proteins in different test platforms. Here, we reported on the evaluation of ELISA and an ICT developed with a new chimeric protein, named DTL-4, based on repetitive antigenic sequences, including those present in the A2 protein. Methods. A total of 1028 sera samples were used for the development and validation of ELISA (321 samples from L. infantum-infected patients, 62 samples from VL/AIDS coinfected patients, 236 samples from patients infected with other diseases, and 409 samples from healthy donors). A total of 520 sera samples were used to develop and validate ICT (249 samples from L. infantum-infected patients, 46 samples from VL/AIDS coinfected patients, 40 samples from patients infected with other diseases, and 185 samples from healthy donors). Findings. Using the validation sera panels, DTL-4-based ELISA displayed an overall sensitivity of 94.61% (95% CI: 89.94-97.28), a specificity of 99.41% (95% CI: 96.39-99.99), and an accuracy of 97.02% (95% CI: 94.61-98.38), while for ICT, sensitivity, specificity, and accuracy values corresponded to 91.98% (95% CI: 86.65-95.39), 100.00% (95% CI: 96.30-100.00), and 95.14% (95% CI: 91.62-97.15), respectively. When testing sera samples from VL/AIDS coinfected patients, DTL-4-ELISA displayed a sensitivity of 77.42% (95% CI: 65.48-86.16), a specificity of 99.41% (95% CI: 96.39-99.99), and an accuracy of 93.51% (95% CI: 89.49%-96.10%), while for DTL-4-ICT, sensitivity was 73.91% (95% CI: 59.74-84.40), specificity was 90.63% (95% CI: 81.02-95.63), and accuracy was 82.00% (95% CI: 73.63-90.91). Conclusion. DTL-4 is a promising candidate antigen for serodiagnosis of VL patients, including those with VL/AIDS coinfection, when incorporated into ELISA or ICT test formats.

Download Full-text

Epidemiological, clinical and laboratory aspects of human visceral leishmaniasis (HVL) associated with human immunodeficiency virus (HIV) coinfection: a systematic review

Parasitology ◽

10.1017/s003118201800080x ◽

2018 ◽

Vol 145 (14) ◽

pp. 1801-1818 ◽

Cited By ~ 3

Author(s):

Iolanda Graepp Fontoura ◽

David Soeiro Barbosa ◽

Antonio Marcus de Andrade Paes ◽

Floriacy Stabnow Santos ◽

Marcelino Santos Neto ◽

...

Keyword(s):

Public Health ◽

Systematic Review ◽

Human Immunodeficiency Virus ◽

Visceral Leishmaniasis ◽

Public Health Problem ◽

Control Measures ◽

High Morbidity ◽

Human Visceral Leishmaniasis ◽

Hiv Coinfection ◽

Immunodeficiency Virus

AbstractCoinfection with human visceral leishmaniasis (HVL) and human immunodeficiency virus (HIV) has become an emerging public health problem in several parts of the world, with high morbidity and mortality rates. A systematic review was carried out in the literature available in PubMed, Scielo and Lilacs related to HVL associated with HIV coinfection, seeking to analyze epidemiological, clinical and laboratory aspects. Of the 265 articles found, 15 articles were included in the qualitative analysis, which referred to the results of HVL treatment in patients coinfected with HIV. In the published articles between 2007 and 2015, 1171 cases of HVL/HIV coinfection were identified, 86% males, average age 34 years, liposomal amphotericin B was the most commonly used drug, cure rates 68 and 20% relapses and 19% deaths, five different countries, bone marrow was used in 10/15 manuscripts. HVL/HIV coinfection is a major challenge for public health, mainly due to the difficulty in establishing an accurate diagnosis, low response to treatment with high relapse rates and evolution to death. In addition, these two pathogens act concomitantly for the depletion of the immune system, contributing to worsening the clinical picture of these diseases, which requires effective surveillance and epidemiological control measures.

Download Full-text

MEASLES OUTBREAK IN A RURAL AREA OF A DEVELOPING COUNTRY: A CASE CONTROL STUDY

Pakistan Journal of Public Health ◽

10.32413/pjph.v7i4.78 ◽

2018 ◽

Vol 7 (4) ◽

pp. 197-201

Author(s):

Mir M Hassan Bullo ◽

Mirza Amir Baig ◽

Jawad Faisal Malik ◽

Ejaz Ahmad Khan ◽

Muazam Abbas Ranjha ◽

...

Keyword(s):

Risk Factors ◽

Vaccine Coverage ◽

Significant Risk ◽

Public Health Problem ◽

Maculopapular Rash ◽

Healthcare Facility ◽

Control Measures ◽

Major Public Health Problem ◽

District Health ◽

Active Case

Background: Measles is highly contagious vaccine preventable disease (VPD), and a major public health problem considered as leading cause of morbidity and mortality in developing countries like Pakistan. An outbreak of measles was reported in Sharifabad Islamabad on 15th of April 2017, and an investigation was launched to assess the magnitude of outbreak, evaluate risk factors and recommend control measures. Methods: A comprehensive house to house active case search along with vaccine coverage survey was conducted from April 19-22, 2017. A case was defined as "onset of maculopapular rash with fever in a resident of Sharifabad with at least one of the following signs/ symptoms, Coryza, Conjunctivitis, Cough, Otitis media or Pneumonia present in between 19 March to 22nd April 2017". Four age & sex matched controls were selected from the neighborhood. Data was collected through interview method using structured questionnaire and vaccination coverage was determined by using Epi survey form. Blood samples were sent for laboratory confirmation. Results: A total of eight cases were identified through active case finding while three were reported by local practitioner. Mean age of cases were 20 months (range 8-36 months). Severely affected age-group was 1-2 years with attack rate of 46%. Around two-third (64%) of cases and a few (16%) of controls were unvaccinated against measles. Contact with measles patient [OR 25.2, CI 3.9-160.1, P=0.00], unvaccinated children [OR 9.2 CI 2.12-40.4, P=0.000], social misconception regarding vaccination [OR 7.8 CI 1.42-42.6, P=0.00], and distance from healthcare facility [OR 5.7 CI 1.15-28.35, P=0.02] were significant risk factors. Vaccine efficacy was 90%. Conclusion: Main reasons of the outbreak were contact with the cases, and low vaccination status. We recommended comprehensive measles vaccination and community awareness sessions. On our recommendations district health authority Islamabad carried out mop up of whole area.

Download Full-text

Healthcare-Associated Infections: Not Only a Clinical Burden, But a Forensic Point of View

Current Pharmaceutical Biotechnology ◽

10.2174/1389201020666190618122649 ◽

2019 ◽

Vol 20 (8) ◽

pp. 658-664 ◽

Cited By ~ 2

Author(s):

Marco Di Paolo ◽

Luigi Papi ◽

Paolo Malacarne ◽

Federica Gori ◽

Emanuela Turillazzi

Keyword(s):

Health Care ◽

Clinical Medicine ◽

Methodological Approach ◽

Care Facility ◽

Public Health Problem ◽

Control Measures ◽

Major Public Health Problem ◽

Healthcare Associated Infections ◽

Open Communication ◽

Healthcare Associated

Background: Healthcare-associated infections (HCAIs) occur when patients receiving treatment in a health care setting develop an infection. They represent a major public health problem, requiring the integration of clinical medicine, pathology, epidemiology, laboratory sciences, and, finally, forensic medicine. Methods: The determination of cause of death is fundamental not only in the cases of presumed malpractice to ascertain the causal link with any negligent behavior both of health facilities and of individual professionals, but also for epidemiological purposes since it may help to know the global burden of HCAIs, that remains undetermined because of the difficulty of gathering reliable diagnostic data. A complete methodological approach, integrating clinical data by means of autopsy and histological and laboratory findings aiming to identify and demonstrate the host response to infectious insult, is mandatory in HCAIs related deaths. Results: Important tasks for forensic specialists in hospitals and health services centers are the promotion of transparency and open communication by health-care workers on the risk of HCAIs, thus facilitating patients’ engagement and the implementation of educational interventions for professionals aimed to improve their knowledge and adherence to prevention and control measures. Conclusion: HCAIs are a major problem for patient safety in every health-care facility and system around the world and their control and prevention represent a challenging priority for healthcare institution and workers committed to making healthcare safer. Clinicians are at the forefront in the war against HCAIs, however, also forensic pathologists have a remarkable role.

Download Full-text

Environmental Vector Control Practices among Households of Patients with Dengue Fever during the Epidemic of 2018 in Kerala, India

Journal of Evidence Based Medicine and Healthcare ◽

10.18410/jebmh/2021/10 ◽

2021 ◽

Vol 8 (02) ◽

pp. 48-52

Author(s):

Chintha Sujatha ◽

Reshma Rajan Sudha ◽

Sreejith Lalitha Krishnankutty ◽

Prajitha Kannamkottapilly Chandrasekharan

Keyword(s):

Vector Control ◽

Dengue Fever ◽

Protective Factor ◽

Significant Risk ◽

Public Health Problem ◽

Community Level ◽

Control Measures ◽

Major Public Health Problem ◽

Cross Sectional ◽

Breeding Habitats

BACKGROUND Dengue fever is a major public health problem in Kerala. Vector control measures practiced at household level is the most cost-effective way of controlling dengue. This study aims to assess environmental measures of vector control practised among households of suspected or confirmed dengue patients in Thiruvananthapuram district of Kerala. METHODS A cross sectional study was done among households of patients diagnosed with dengue fever and reported in Integrated Disease Surveillance Programme (IDSP) in Thiruvananthapuram district from June to December 2018. Investigators interviewed the household members and made direct observations to collect data on vector control practices using a structured questionnaire. RESULTS A total of 108 houses were surveyed. Potential breeding habitats were found in 58 (53.7 %) houses. Aedes larva was found in containers from four (3.7 %) houses. Dry day observance was not regular with only 5 (4.6 %) houses practicing it weekly. Waste management practiced was proper in 47 (43.5 %) houses. Community level pre monsoon preparedness for epidemics was done in the vicinity of 53 (49.1 %) houses and it was found to be a protective factor against presence of breeding habitats in and around houses (p = 0.013). Low education (p = 0.012) and low occupational status (p = 0.017) were found to be significant risk factors. CONCLUSIONS Even during an epidemic, with occurrence of infections in the family, only half of the households are practising adequate vector control methods. Community level interventions and targeted information education campaign will help improve practice of environmental methods of vector control in dengue. KEYWORDS Dengue, Vector Control, Aedes Control, Environmental Methods, Community Interventions

Download Full-text

Development and Clinical Evaluation of Loop-Mediated Isothermal Amplification (LAMP) Assay for the Diagnosis of Human Visceral Leishmaniasis in Brazil

BioMed Research International ◽

10.1155/2019/8240784 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Daniel Moreira de Avelar ◽

Débora Moreira Carvalho ◽

Ana Rabello

Keyword(s):

Visceral Leishmaniasis ◽

Lamp Assay ◽

Isothermal Amplification ◽

Health Concern ◽

Serological Tests ◽

Blood Samples ◽

Loop Mediated Isothermal Amplification ◽

Human Visceral Leishmaniasis ◽

Highly Sensitive ◽

Sensitivity Specificity

Visceral leishmaniasis (VL) is considered a major public health concern in Brazil and several regions of the world. A recent advance in the diagnosis of infectious diseases was the development of loop-mediated isothermal amplification (LAMP). The aim of this study was to develop and evaluate a new LAMP assay for detection of K26 antigen-coding gene of L. donovani complex. A total of 219 blood samples of immunocompetent patients, including 114 VL cases and 105 non-VL cases, were analyzed for the diagnosis of VL in the present study. Diagnostic accuracy was calculated against a combination of parasitological and/or serological tests as a reference standard. The results were compared to those of kDNA Leishmania-PCR. The detection limit for the K26-Lamp assay was 1fg L. infantum purified DNA and 100 parasites/mL within 60 min of amplification time with visual detection for turbidity. The assay was specific for L. donovani complex. Sensitivity, specificity, and accuracy were 98.2%, 98.1%, and 98.2%, respectively, for K26-LAMP and 100%, 100%, and 100%, respectively, for kDNA Leishmania-PCR. Excellent agreement was observed between K26-LAMP and kDNA Leishmania-PCR assays (K = 0.96). A highly sensitive and specific LAMP assay targeting K26 antigen-coding gene of L. donovani complex was developed for diagnosis in peripheral blood samples of VL patients.

Download Full-text

Prevalence, antimicrobial susceptibility pattern, and associated factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018

10.21203/rs.2.22938/v4 ◽

2020 ◽

Author(s):

Haftom Legese ◽

Tsega Kahsay ◽

Aderajew Gebrewahd ◽

Brhane Berhe ◽

Berhane Fseha ◽

...

Keyword(s):

Foodborne Pathogens ◽

Antimicrobial Susceptibility ◽

Associated Factors ◽

Public Health Problem ◽

Hand Washing ◽

Control Measures ◽

Major Public Health Problem ◽

Northern Ethiopia ◽

Food Handlers ◽

Cross Sectional

Abstract Background: Food handlers play a significant role in the transmission of foodborne infections. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem globally. Thus, this study aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of Salmonella and Shigella among food handlers.Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 with a corresponding 95% confidence interval was considered statistically significant.Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, hand washing after using the bathroom, hand washing after touching dirty materials, hand washing before food handling, and fingernails status were significant associated factors identified. None of the Salmonella and Shigella isolates were sensitive to ampicillin. On the other hand, low resistance was found for chloramphenicol, ceftriaxone, and ciprofloxacin.Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers was 22 (7.3%) and 11 (3.7%) respectively. Such colonized food handlers can contaminate food, drinks and could serve as a source of infection to consumers via the food chain. This indicates that there is a need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.

Download Full-text

Prevalence, antimicrobial susceptibility pattern, and associated factors of Salmonella and Shigella among food handlers in Adigrat University student’s cafeteria, Northern Ethiopia, 2018

10.21203/rs.2.22938/v6 ◽

2020 ◽

Author(s):

Haftom Legese ◽

Tsega Kahsay ◽

Aderajew Gebrewahd ◽

Brhane Berhe ◽

Berhane Fseha ◽

...

Keyword(s):

Foodborne Pathogens ◽

Antimicrobial Susceptibility ◽

Associated Factors ◽

Public Health Problem ◽

Hand Washing ◽

Control Measures ◽

Major Public Health Problem ◽

Northern Ethiopia ◽

Food Handlers ◽

Cross Sectional

Abstract Background: Food handlers play a significant role in the transmission of foodborne infections. Salmonella and Shigella are the most common foodborne pathogens and their infections are a major public health problem globally. Thus, this study aimed to determine the prevalence, antimicrobial susceptibility patterns, and associated factors of Salmonella and Shigella colonization among food handlers.Methodology: A cross-sectional study was conducted from March to August 2018 at Adigrat University student cafeteria, Northern Ethiopia. Data on socio-demographic and associated factors were collected using a structured questionnaire. Fresh stool samples were collected from 301 food handlers and transported to Adigrat University Microbiology Laboratory. Bacterial isolation and antimicrobial susceptibility test were performed using standard bacteriological methods. Data analysis was performed using SPSS version 22 and P < 0.05 where a corresponding 95% confidence interval was considered statistically significant.Results: A total of 301 food handlers were included in this study. The majority of study participants were females 265 (88.0 %). About 22 (7.3%) and 11 (3.7%) of food handlers were found to be positive for Salmonella and Shigella respectively. Hand washing after using a bathroom with water only, no hand washing after using the bathroom, no hand washing after touching dirty materials, no hand washing before food handling, and untrimmed fingernails were significant associated factors identified. None of the Salmonella and Shigella isolates were sensitive to ampicillin, yet low resistance against chloramphenicol, ceftriaxone, and ciprofloxacin was found. Conclusion: The present study revealed that the prevalence of Salmonella and Shigella among food handlers was 22 (7.3%) and 11 (3.7%) respectively. Such colonized food handlers can contaminate food, and drinks and could serve as a source of infection to consumers. This indicates that there is a need for strengthened infection control measures to prevent Salmonella and Shigella transmission in the students’ cafeteria.

Download Full-text

Study on prevalence of hepatitis B in pregnant women and its effect on maternal and fetal outcome at tertiary care centre

International Journal of Reproduction Contraception Obstetrics and Gynecology ◽

10.18203/2320-1770.ijrcog20172069 ◽

2017 ◽

Vol 6 (6) ◽

pp. 2238

Author(s):

Sunita Mishra ◽

Priyali Purandre ◽

Ratna Thakur ◽

Shweta Agrawal ◽

Madhuri Alwani

Keyword(s):

Hepatitis B ◽

Pregnant Women ◽

Tertiary Care ◽

Mode Of Delivery ◽

Public Health Problem ◽

Pregnant Patient ◽

Control Measures ◽

Major Public Health Problem ◽

Tertiary Care Centre ◽

Vaccination Programs

Background: Hepatitis-B is caused by double stranded DNA virus. Prevalence of hepatitis B in pregnant woman worldwide is 2.5 to 1.5% whereas in India it is 2 to 7.7%.Methods: This is a retrospective study conducted at SAMC and PGI, Indore between January 2016 to December 2016. Hepatitis- B prevalence and outcome was assessed by doing routine screening of hepatitis B antigen in our indoor patients and finding out their maternal and fetal outcome.Results: Total 3567 deliveries were conducted during study period, out of them 39 were diagnosed as HbsAg positive pregnant patient; so, prevalence was found to be 1.09%. out of these, 84.6% were booked cases, mode of delivery was vaginal in 66.67% cases, preterm Delivery was in 10.26% of cases, meconium stained liquor was found in 5.13% cases, maternal mortality was nil, perinatal mortality was found in 2.56% cases and 5.13% cases were admitted in NICU.Conclusions: Screening of all pregnant women for HbsAg irrespective of risk factors will definitely help to know the correct prevalence and reduce the transmission of hepatitis B infection. Hepatitis B is a major public health problem in India and will continue to be until appropriate nationwide vaccination programs and other control measures are established.

Download Full-text

Spatial distribution of human and canine visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brasil, 1994-1997

Cadernos de Saúde Pública ◽

10.1590/s0102-311x2001000500023 ◽

2001 ◽

Vol 17 (5) ◽

pp. 1231-1239 ◽

Cited By ~ 62

Author(s):

Cláudia Di Lorenzo Oliveira ◽

Renato Martins Assunção ◽

Ilka Afonso Reis ◽

Fernando Augusto Proietti

Keyword(s):

Spatial Distribution ◽

Visceral Leishmaniasis ◽

Incidence Rates ◽

Control Measures ◽

Canine Visceral Leishmaniasis ◽

Prevalence Rates ◽

Smooth Maps ◽

Human Visceral Leishmaniasis ◽

Minas Gerais State ◽

Belo Horizonte

In this paper, we present spatial analysis of the association between all incidents cases of human Visceral Leishmaniasis and seropositive dogs, from 1994 to 1997 in Belo Horizonte, a large Brazilian city. We geocoded 158 human cases and 11,048 seropositive dogs and compared canine prevalence rates with Human Bayesian Incidence rates in the same areas. We also used Knox's test to evaluate the hypothesis of space-time clustering of human cases in the period. Additionally, we used Kernel's maps for seropositive dogs distribution and located the human cases in the resulting smooth maps. We concluded that human and dog rates are correlated. Also, the Visceral Leishmaniasis in Belo Horizonte spread quickly, but apart from the rates' magnitude, it has kept the same spatial pattern through time. We believe it is possible to use this technique to choose areas to implement control measures against Visceral Leishmaniasis in a more efficient way.

Download Full-text