scholarly journals Detection and Genotyping of Cryptosporidium Spp. in Biofilms and Cattle Feces From the Black River Watershed, Jamaica

2021 ◽  
Author(s):  
Amanda Morris

Cryptosporidium is a protozoan parasite that causes the gastrointestinal disease cryptosporidiosis. The disease is endemic in most tropical countries including Jamaica; yet underreported from environmental sources. This is of concern because the primary source of anthropocentric cryptosporidiosis is surface water contaminated by human effluent and animal waste in runoff. This dissertation therefore, focuses on three main areas of research: 1) optimization and assessment of effective methods for detecting Cryptosporidium from environmental samples; 2) application of methods to analyze biofilm and cattle feces collected from the Black River watershed, located in the rural parish of St. Elizabeth, Jamaica; 3) molecular characterization of PCR-positive detections to identify Cryptosporidium species and genotypes, thereby provide inference to waterborne transmission, mitigation, and zoonotic potential within the region. First, foundational work of this dissertation focused on the development of in situ biofilm sampling for Cryptosporidium detection. Application was then performed in the Black River network for initial screening of oocysts from biofilms collected from 5 sites, and 119 cattle fecal specimens collected from 10 farms. Multiple techniques were employed to confirm the absence or presence of Cryptosporidium, including Immunofluorescence Assay (IFA) and Modified Acid-Fast (MAF) microscopy, Enzyme-Linked Immunosorbent Assay (ELISA), and Polymerase Chain Reaction (PCR). Results show that oocysts were widely dispersed in biofilms and cattle specimens. Highest prevalence was observed amoung dairy cattle compared to beef cattle, presumably due to confined space. Results also highlight inconsistencies between detection methods, confirming that from environmental sources—where inhibitors are abundant and oocysts concentrations are naturally low—a single technique may be ineffective for understanding transmission dynamics. The second part of this dissertation focused on molecular characterization. Fourteen PCR-positive biofilm and cattle samples were subjected to gene sequencing and phylogeny. A low species diversity consisting of C. parvum and C. hominis were identified; the two most common species involved in anthropocentric infections. A specific 18S rRNA isolate of C. parvum was found in both biofilm and cattle samples (with 99% identity), indicating that a geographically distinct, clonal genotype of C. parvum potentially exists within the region. Further subtyping analysis of the gp60 locus identified one C. hominis subtype (IbA9G2), formally identified in human populations worldwide. Moreover, the IbA9G2 subtype was recently linked to calf infections in France, as well as a waterborne outbreak in Germany. In conclusion, this dissertation is the first to detect and characterize Cryptosporidium species and genotypes from surface water biofilms and cattle feces in Jamaica, providing informative data pertaining to public health and animal agriculture. Moreover, this research advocates the importance of utilizing multiple detection methods and sources for effective screening of Cryptosporidium throughout the environment. Whilst meaningful interpretations of Cryptosporidium population structures are developed, useful databases can form through analyzing a well-planned set of environmental samples.

2021 ◽  
Author(s):  
Amanda Morris

Cryptosporidium is a protozoan parasite that causes the gastrointestinal disease cryptosporidiosis. The disease is endemic in most tropical countries including Jamaica; yet underreported from environmental sources. This is of concern because the primary source of anthropocentric cryptosporidiosis is surface water contaminated by human effluent and animal waste in runoff. This dissertation therefore, focuses on three main areas of research: 1) optimization and assessment of effective methods for detecting Cryptosporidium from environmental samples; 2) application of methods to analyze biofilm and cattle feces collected from the Black River watershed, located in the rural parish of St. Elizabeth, Jamaica; 3) molecular characterization of PCR-positive detections to identify Cryptosporidium species and genotypes, thereby provide inference to waterborne transmission, mitigation, and zoonotic potential within the region. First, foundational work of this dissertation focused on the development of in situ biofilm sampling for Cryptosporidium detection. Application was then performed in the Black River network for initial screening of oocysts from biofilms collected from 5 sites, and 119 cattle fecal specimens collected from 10 farms. Multiple techniques were employed to confirm the absence or presence of Cryptosporidium, including Immunofluorescence Assay (IFA) and Modified Acid-Fast (MAF) microscopy, Enzyme-Linked Immunosorbent Assay (ELISA), and Polymerase Chain Reaction (PCR). Results show that oocysts were widely dispersed in biofilms and cattle specimens. Highest prevalence was observed amoung dairy cattle compared to beef cattle, presumably due to confined space. Results also highlight inconsistencies between detection methods, confirming that from environmental sources—where inhibitors are abundant and oocysts concentrations are naturally low—a single technique may be ineffective for understanding transmission dynamics. The second part of this dissertation focused on molecular characterization. Fourteen PCR-positive biofilm and cattle samples were subjected to gene sequencing and phylogeny. A low species diversity consisting of C. parvum and C. hominis were identified; the two most common species involved in anthropocentric infections. A specific 18S rRNA isolate of C. parvum was found in both biofilm and cattle samples (with 99% identity), indicating that a geographically distinct, clonal genotype of C. parvum potentially exists within the region. Further subtyping analysis of the gp60 locus identified one C. hominis subtype (IbA9G2), formally identified in human populations worldwide. Moreover, the IbA9G2 subtype was recently linked to calf infections in France, as well as a waterborne outbreak in Germany. In conclusion, this dissertation is the first to detect and characterize Cryptosporidium species and genotypes from surface water biofilms and cattle feces in Jamaica, providing informative data pertaining to public health and animal agriculture. Moreover, this research advocates the importance of utilizing multiple detection methods and sources for effective screening of Cryptosporidium throughout the environment. Whilst meaningful interpretations of Cryptosporidium population structures are developed, useful databases can form through analyzing a well-planned set of environmental samples.


1999 ◽  
Vol 65 (3) ◽  
pp. 1055-1060 ◽  
Author(s):  
Melissa O. Peplow ◽  
Maria Correa-Prisant ◽  
Martha E. Stebbins ◽  
Frank Jones ◽  
Peter Davies

ABSTRACT To reduce human exposure to Salmonella spp. in poultry products, broiler chicken flocks have been tested by culture methods. Since the standard techniques may take 3 to 5 days, rapid detection methods have been developed. In this study we tested the performance of three rapid tests originally developed for food samples by using environmental samples obtained from poultry houses. These rapid tests were Reveal, an enzyme-linked immunosorbent assay from Neogen Corp.; BIND, a bacterial ice nucleation detection method from Idetek Corp.; and a filter monitor method from Future Medical Technologies, Inc. For the standard culture, brilliant green with novabiocin and xylose–lysine–tergitol-4 agar were used for presumptive identification, and identities were confirmed by using poly-O antisera. Environmental samples were collected from farms belonging to an integrated poultry company prior to chick placement and 1 week before slaughter. Sensitivities, specificities, and predictive values with 95% confidence intervals were calculated. Statistical differences were determined by using McNemar’s chi square test. The sensitivities of the different tests were not stable, varying widely between sample times, and were affected by freezing of the samples. All of the rapid tests had low sensitivities, which led to many false-negative results. All tests were able to detect Salmonella spp. at a concentration of 10 CFU/ml in at least one of four trials. The BIND and Reveal tests were simple to use with multiple samples and reduced laboratory time by up to 1 day. Based on our results, we do not recommend that any of these rapid tests, in their present state of development, be utilized with environmental samples collected with drag swabs.


2019 ◽  
Vol 40 (6Supl2) ◽  
pp. 3313
Author(s):  
Valéria Régia Franco Sousa ◽  
Álvaro Felipe de Lima Ruy Dias ◽  
Juliana Yuki Rodrigues ◽  
Mariana de Medeiros Torres ◽  
Janaína Marcela Assunção Rosa Moreira ◽  
...  

Visceral Leishmaniasis (VL) is a parasitic zoonosis expanding in Brazil. Several municipalities in the state of Mato Grosso including those on the river Cuiabá have reported the incidence of both human and canine cases and the identification of sandfly vector, Lutzomyia longipalpis and Lu. cruzi. Dogs are considered the main reservoir of Leishmania chagasi in the urban areas, hence, we devised a cross-sectional study aimed at assessing the prevalence of the infection in the dogs of riverside communities on Cuiabá River watershed by parasitological (parasitic isolation in culture), serological, and molecular methods. Of the 248 surveyed dogs, 24 were positive in enzyme linked immunosorbent assay (ELISA) or immunofluorescence antibody test (IFAT), with a prevalence of 9.7%. The riverside communities located in the town of Santo Antonio do Leverger displayed a higher prevalence of the disease than the cities of Cuiabá and Várzea Grande; however, the difference was not statistically significant (p > 0.05). Dogs born in the communities had a 3.24-fold higher risk of acquiring the infection. Promastigote were isolated in the axenic culture from the bone marrow samples and intact skin. Further, DNA of Leishmania sp. was detected in the bone marrow samples, lymph nodes, leukocyte cover, and skin of only one examined dog. These samples were sequenced and they showed 99% homology to L. infantum. To conclude, we observed a higher prevalence of infection in Riverside communities of Santo Antonio do Leverger and the confirmation of autochthony in these areas justifies the surveillance actions to minimise the risk of transmission within the riverine community itself, besides its dissemination to other areas by tourism.


2017 ◽  
Vol 25 (8) ◽  
pp. 7688-7698 ◽  
Author(s):  
Zhidan Wen ◽  
Xiaoli Huang ◽  
Dawen Gao ◽  
Ge Liu ◽  
Chong Fang ◽  
...  

Author(s):  
K. Saratbabu ◽  
K. Vemana ◽  
A.K. Patibanda ◽  
B. Sreekanth ◽  
V. Srinivasa Rao

Background: Peanut stem necrosis disease (PSND) caused by Tobacco streak virus (TSV) is a major constraint for groundnut production in Andhra Pradesh (A.P.). However, studies on prevalence and spread of the disease confined to only few districts of A.P. with this background current study focused on incidence and spread of the disease in entire state of A.P. Further an isolate of TSV occurring in A.P. characterized on the basis of genetic features by comparing with other TSV isolates originated from different hosts and locations from world.Methods: Roving survey was conducted during kharif 2017-18 in groundnut growing districts of Andhra Pradesh (A.P.) for peanut stem necrosis disease incidence. Groundnut plants showing PSND symptoms were collected and tested with direct antigen coating enzyme linked immunosorbent assay (DAC-ELISA). Groundnut samples found positive by ELISA once again tested by reverse transcription polymerase chain reaction (RT-PCR). The representative TSV-GN-INDVP groundnut isolate from Prakasham district was maintained on cowpea seedlings by standard sap inoculation method in glasshouse for further molecular characterization. The Phylogenetic tree for coat protein (CP) gene was constructed using aligned sequences with 1000 bootstrap replicates following neighbor-joining phylogeny.Result: Thirty-eight (52.7%) of seventy-two groundnut samples collected from different locations in A.P were given positive reaction to TSV by DAC-ELISA. For the first time, PSND incidence observed in coastal districts (Krishna, Guntur, Sri Pottisriramulu Nellore, Prakasham) of A.P. Maximum PSND incidence recorded from Bathalapalli (22.2%) and the minimum incidence in Mulakalacheruvu (4.1%). The coat protein (CP) gene of TSV-GN-INDVP groundnut isolate was amplified by RT-PCR and it shared maximum per cent nucleotide identity (97.51-98.62%) with TSV isolates from groundnut and other different crops reported in India. All Indian isolates cluster together irrespective of crop and location based on the phylogenetic analysis.


2021 ◽  
Vol 7 (1) ◽  

Respiratory tract infections (RTIs) are the most common and severe infectious diseases in developing countries. Acinetobacter baumannii is the bacterium known as causative organism for respiratory tract infections in human populations. The Report suggests that co-infection of Acinetobacter baumannii with Mycobacterium tuberculosis together increases health complications in multidrug resistant tuberculosis (MDR-TB) positive patients and creates fatal damage to the ailing population. In our study, 106 sputum samples of MDR-TB positive patients from Northern Punjab were studied. The isolation of A. baumannii from sputum of MDR-TB patients was done on selective media and initially screened by Oxidase and Catalase based identification followed by microscopic examination. Afterward, only ten suspected isolates of A. baumannii were again selected for further characterization for MDR by using Disc diffusion method. Antibiograms against number of antibiotics were accurately determined. Of these 10 isolates, 8 sample were found resistant to levofloxacin and subjected to molecular characterization using bla-OXA-51 primers. Only 3 out of 106 (2.83 %) isolates were confirmed as MDR strains of A. baumannii. These results show the coexistence of MDR A. bauminnii with MDR-TB patients of Northern Punjab, Pakistan. In Northern Punjab regions a higher percentage (3 cases) of MDR- TB were detected, which were co-infected with Acinetobacter baumannii among hospitalized patients. These findings may show unhygienic hospital environment or practices which leads to the co-infection.


Author(s):  
Nicholas Johnson ◽  
Mar Fernández de Marco ◽  
Armando Giovannini ◽  
Carla Ippoliti ◽  
Maria Danzetta ◽  
...  

Mosquito-borne viruses are the cause of some of the greatest burdens to human health worldwide, particularly in tropical regions where both human populations and mosquito numbers are abundant. Due to a combination of anthropogenic change, including the effects on global climate and wildlife migration there is strong evidence that temperate regions are undergoing repeated introduction of mosquito-borne viruses and the re-emergence of viruses that previously were not detected by surveillance. In Europe, the repeated introductions of West Nile and Usutu viruses have been associated with bird migration from Africa, whereas the autochthonous transmission of chikungunya and dengue viruses has been driven by a combination of invasive mosquitoes and rapid transcontinental travel by infected humans. In addition to an increasing number of humans at risk, livestock and wildlife, are also at risk of infection and disease. This in turn can affect international trade and species diversity, respectively. Addressing these challenges requires a range of responses both at national and international level. Increasing the understanding of mosquito-borne transmission of viruses and the development of rapid detection methods and appropriate therapeutics (vaccines / antivirals) all form part of this response. The aim of this review is to consider the range of mosquito-borne viruses that threaten public health in Europe and the eastern Mediterranean, and the national response of a number of countries facing different levels of threat.


2021 ◽  
Vol 13 (19) ◽  
pp. 10740
Author(s):  
Linyan Pan ◽  
Junfeng Dai ◽  
Zhiqiang Wu ◽  
Liangliang Huang ◽  
Zupeng Wan ◽  
...  

When considering the factors affecting the spatial and temporal variation of nitrogen and phosphorus in karst watersheds, the unique karst hydrogeology as an internal influencing factor cannot be ignored, as well as natural factors such as meteorological hydrology and external factors such as human activities. A watershed-scale field investigation was completed to statistically analyze spatial and temporal dynamics of nitrogen and phosphorus through the regular monitoring and collection of surface water and shallow groundwater in the agricultural-dominated Mudong River watershed in the Huixian Karst Wetland over one year (May 2020 to April 2021). Our research found that non-point source pollution of nitrogen (84.5% of 239 samples TN > 1.0 mg/L) was more serious than phosphorus (7.5% of 239 samples TP > 0.2 mg/L) in the study area, and shallow groundwater nitrogen pollution (98.3% of 118 samples TN > 1.0 mg/L) was more serious than surface water (68.6% of 121 samples TN > 1.0 mg/L). In the three regions with different hydrodynamic features, the TN concentration was higher and dominated by NO3−-N in the river in the northern recharge area, while the concentrations of TN and TP were the highest in shallow groundwater wells in the central wetland core area and increased along the surface water flow direction in the western discharge area. This research will help improve the knowledge about the influence of karst hydrodynamic features on the spatial patterns of nitrogen and phosphorus in water, paying attention to the quality protection and security of water in karst areas with a fragile water ecological environment.


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