Leptospirosis Seroconversion Surveillance Among US Marines Assigned to Japan, 2011–2015

Abstract Introduction: Leptospirosis is a global zoonotic disease spread through contact with contaminated water/soil. The US soldiers at the military bases in these countries are extremely vulnerable, as most of them are immunologically naïve to the responsible pathogen. No recent sero-epidemiological data of leptospirosis among US Marines stationed in Japan were available. Materials and Methods: In this study, we analyzed the presence of leptospirosis in US Marines stationed in Japan. One thousand posttour sera samples were analyzed by enzyme-linked immunosorbent assay for Leptospira-specific Immunoglobulin G. Results: Among these 1,000 posttour samples, 85 of them were positive and corresponding pretour samples were analyzed by enzyme-linked immunosorbent assay also. Seroconversion occurred for 35 (3.5%) Marines during their assignment to Japan. These results also indicate that 50 Marine personnels were exposed to leptospires before their assignment to Japan, perhaps because of previous exposure to leptospires at home. Conclusion: The 5% rate of seroconversion in 2013 and 2014 suggests that leptospirosis is a potential threat for Marines in the endemic region in Japan.

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Development of an Enzyme-Linked Immunosorbent Assay for the Detection of Antibody to Epizootic Hemorrhagic Disease of Deer Virus

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063870001200207 ◽

2000 ◽

Vol 12 (2) ◽

pp. 142-145 ◽

Cited By ~ 18

Author(s):

James O. Mecham ◽

Michael M. Jochim

Keyword(s):

Immunosorbent Assay ◽

Enzyme Linked Immunosorbent Assay ◽

Hemorrhagic Disease ◽

Structural Protein ◽

Serum Samples ◽

Epizootic Hemorrhagic Disease ◽

Diagnostic Potential ◽

The Us ◽

Serotype 1 ◽

Infected Cells

An enzyme-linked immunosorbent assay has been developed to detect antibodies to epizootic hemorrhagic disease of deer virus (EHDV). The assay incorporates a monoclonal antibody to EHDV serotype 2 (EHDV-2) that demonstrates specificity for the viral structural protein, VP7. The assay was evaluated with sequential sera collected from cattle experimentally infected with EHDV serotype 1 (EHDV-1) and EHDV-2, as well as the four serotypes of bluetongue virus (BTV), BTV-10, BTV-11, BTV-13, and BTV-17, that currently circulate in the US. A competitive and a blocking format as well as the use of antigen produced from both EHDV-1-and EHDV-2-infected cells were evaluated. The assay was able to detect specific antibody as early as 7 days after infection and could differentiate animals experimentally infected with EHDV from those experimentally infected with BTV. The diagnostic potential of this assay was demonstrated with field-collected serum samples from cattle, deer, and buffalo.

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First Detection of Faba bean necrotic yellow virus in Spain

Plant Disease ◽

10.1094/pdis.2000.84.6.707b ◽

2000 ◽

Vol 84 (6) ◽

pp. 707-707 ◽

Cited By ~ 7

Author(s):

M. Babin ◽

V. Ortíz ◽

S. Castro ◽

J. Romero

Keyword(s):

Faba Bean ◽

Acyrthosiphon Pisum ◽

Virus Disease ◽

Epidemiological Data ◽

Aphid Transmission ◽

Enzyme Linked Immunosorbent Assay ◽

Yellow Virus ◽

Potential Threat ◽

Bean Plants ◽

Faba Beans

Faba bean necrotic yellow virus (FBNYV) was not detected during 1994 to 1996 field surveys of faba beans (Vicia faba L.) in Spain (1). In 1997, however, one sample with symptoms of necrosis, collected in Baleares, was tested using ELISA (enzyme-linked immunosorbent assay) and was positive for both Tomato spotted wilt virus (TSWV) and FBNYV. FBNYV is a single-strand DNA virus that is transmitted by aphids and is the main virus disease of broad bean in North Africa and West Asia (2). During 1997 to 1999, faba bean plants with symptoms of necrosis, yellowing, small leaves, and stunting were collected from several fields in the Murcia Region (Spain) and were analyzed using ELISA. To detect FBNYV, we used monoclonal 2E9 supplied by H. J. Vetten (Institute of Plant Virology, Microbiology and Biosafety, BBA, Braunschweig, Germany). Of 700 samples analyzed, 34 were positive for FBNYV. Of the 34 positive samples, 12 tested positive, using commercial antiserum from Loewe, Inc. (Munich) for mixed infections with TSWV. FBNYV was transmitted to healthy faba bean plants by aphids (Acyrthosiphon pisum) in greenhouse experiments and was confirmed by ELISA. Preliminary epidemiological data showed a gradual increase in the number of plants infected with time in the same field. Aphid transmission of FBNYV to faba beans has established the disease in Spain and is a potential threat to other leguminous crops. This is the first report of a nanovirus in Europe. References: (1) J. Fresno et al. Plant Dis. 81:112, 1997. (2) L. Katul et al. Ann. Appl. Biol. 123:629, 1993.

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Principles and techniques towards successful development of enzyme-linked immunosorbent assay (ELISA) for dioxin analysis

10.32920/ryerson.14648613.v1 ◽

2021 ◽

Author(s):

Wei Zhang

Keyword(s):

Immunosorbent Assay ◽

Environmental Protection Agency ◽

High Resolution Mass Spectrometry ◽

Enzyme Linked Immunosorbent Assay ◽

Environmental Matrices ◽

Successful Development ◽

Trace Level ◽

The Us ◽

Us Epa ◽

Technical Details

Dioxins are highly toxic, persistent and bio-accumulative compounds. Laboratory detection of dioxins in various environmental matrices is one of the most technically demanding and expensive tasks in analytical chemistry.The cost to analyze a soil sample by conventional gas chromatography-high resolution mass spectrometry (GC-HRMS) is approximately $1,900 USC accordign to the Unisted States Environmental Protection Agency (US EPA) (Billets, 2005). As an alternative, enzyme-linked immunosorbent assay (ELISA) for dioxin analysis has been commercially available for over a decade and recognized as the US EPA Method 3025. However, assay attributes need to be examined, especially at trace level detection. In this study, sources of error in ELISA, such as background contamination and dioxin-like polycholrinated biphenyl (dl-BCB) cross-reactions have been investigated. Quality assurance data on spikes have been reviewed and the recovery was estimated to be 70%. Technical details that are crucial for the performance of dioxin in ELISA were also identified and addressed.

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Seapower, geostrategic relations, and islandness: The World War II Destroyers for Bases deal

Island Studies Journal ◽

10.24043/isj.139 ◽

2020 ◽

Author(s):

Colin Flint

Keyword(s):

World War Ii ◽

Balance Of Power ◽

Media Representations ◽

Military Bases ◽

The Bahamas ◽

British Guiana ◽

Historical Processes ◽

The Us ◽

The Military

The Destroyers for Bases deal was signed on March 27, 1941, and transferred fifty aging US destroyers to Great Britain in exchange for 99-year leases of bases on the British controlled islands of Newfoundland, Bermuda, Trinidad, Jamaica, Antigua, St. Lucia, the Bahamas, and one in British Guiana. The deal highlights how US strategic planners came to see the value of the islands because of their relationality. Three forms of relationality are discussed: the land/sea dialectic; spatial connectivity; and the changing geopolitical balance of power. Relationality is a factor in four strategic calculations: other islands; other continents; other oceans; and the conjuncture of long-term historical processes of hegemonic decline and rise. The relationality of the islands is understood through the lens of seapower as both input (the military bases) and output (the projection of force). Media representations of the deal are discussed to illustrate how islandness was implicit in the narration of the islands as being of strategic benefit to the US. The conclusions drawn emphasize the need to see strategic and military actors as agents who are aware of and construct island relationality; and the need for islands to be included as one of the inputs of seapower.

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Principles and techniques towards successful development of enzyme-linked immunosorbent assay (ELISA) for dioxin analysis

10.32920/ryerson.14648613 ◽

2021 ◽

Author(s):

Wei Zhang

Keyword(s):

Immunosorbent Assay ◽

Environmental Protection Agency ◽

High Resolution Mass Spectrometry ◽

Enzyme Linked Immunosorbent Assay ◽

Environmental Matrices ◽

Successful Development ◽

Trace Level ◽

The Us ◽

Us Epa ◽

Technical Details

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Nucleocapsid Protein-Based Enzyme-Linked Immunosorbent Assay for Detection and Differentiation of Antibodies against European and North American Porcine Reproductive and Respiratory Syndrome Virus

Clinical and Vaccine Immunology ◽

10.1128/cdli.9.6.1183-1191.2002 ◽

2002 ◽

Vol 9 (6) ◽

pp. 1183-1191 ◽

Cited By ~ 6

Author(s):

Torsten Seuberlich ◽

Jon-Duri Tratschin ◽

Barbara Thür ◽

Martin A. Hofmann

Keyword(s):

Immunosorbent Assay ◽

North American ◽

Nucleocapsid Protein ◽

Simultaneous Detection ◽

The United States ◽

Respiratory Syndrome Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Epidemiological Surveys ◽

The Us ◽

The Eu

ABSTRACT Two types of porcine reproductive and respiratory syndrome virus (PRRSV) have been reported, the European type (EU PRRSV) and the North American type (US PRRSV). We developed a dual enzyme-linked immunosorbent assay (ELISA) for the simultaneous detection and differentiation of serum antibodies directed against either of the two PRRSV types. This tandem PRRS ELISA is based on affinity-purified recombinant nucleocapsid protein expressed in Escherichia coli. Sensitivity and specificity were assessed by using the IDEXX HerdChek PRRS ELISA and the indirect immunofluorescence assay as reference tests. A total of 1,571 sera originating from the United States, Europe, and two PRRS-free countries, i.e., Switzerland and New Zealand, were used for validation of the tandem PRRS ELISA. The new test performed at least as well as the reference tests in regard to sensitivity (0.94 for the US PRRS ELISA and 0.93 for the EU PRRS ELISA) and specificity (0.96 for the US PRRS ELISA and 0.99 for the EU PRRS ELISA). Positive sera were correctly differentiated in 582 of 591 cases, indicating a high differentiation capability of this dual ELISA. The robustness and repeatability of the test were assessed and found to be appropriate for diagnostic applications. Taken together, the data indicate that the tandem PRRS ELISA described here is the first differentiation ELISA for PRRSV serology based on recombinant antigen. It is convenient with respect to antigen production, and it is reliable, economical, and highly sensitive and specific. Thus, it is considered to be a powerful tool for routine diagnostics, epidemiological surveys, and outbreak investigations.

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Serological Diagnosis of Feline Tegumentary Leishmaniasis by Indirect Immunofluorescence (IFI) and Enzyme-Linked Immunosorbent Assay (ELISA) in an Endemic Area in Brazil

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.81299 ◽

2018 ◽

Vol 44 (1) ◽

pp. 7

Author(s):

Fabiano Borges Figueiredo ◽

Lílian Dias Nascimento ◽

Tassia Cristina Bello de Vasconcelos ◽

Maria De Fátima Madeira ◽

Eliame Mouta Confort ◽

...

Keyword(s):

Immunosorbent Assay ◽

Indirect Immunofluorescence ◽

Endemic Area ◽

Public Health Problem ◽

Diagnostic Techniques ◽

Enzyme Linked Immunosorbent Assay ◽

Domestic Cats ◽

Endemic Region ◽

Tegumentary Leishmaniasis ◽

Epidemiological Surveys

Background: American tegumentary leishmaniasis (ATL) is a serious public health problem, and the participation of domestic cats in its epidemiological process has not yet been fully elucidated. Therefore, the standardization of monitoring methodologies of cat populations becomes important for the generation of information on the disease. In Brazil, ATL presents a wide geographical distribution, being Leishmania (Viannia) braziliensis its etiologic agent of ATL in Rio de Janeiro. The main objective of the present study was investigate the presence of specific anti-Leishmania (Viannia) braziliensis Immunoglobulin G (IgG) in 34 cats from an ATL endemic area in this municipality.Materials, Methods & Results: Sera from three cats from the study area naturally infected with Leishmania (Viannia) braziliensis were used as positive control. Analyses were performed with antigen preparations using indirect immunofluorescence (IFI) and enzyme-linked immunosorbent assay (ELISA). We found prevalence rates of 20.6% (7/34) in the IFI and 14.7% (5/34) in the ELISA. Specificity was 87.1% for the IFI and 93.5% for the ELISA, and both tests presented sensitivity of 100%. Concordance between the used tests was assessed as moderate.Discussion: By conducting a feline serological survey in an endemic area for ATL we provide information on the involvement of this species in such epidemiological process. In this context, the participation of the cat in cycles of leishmaniases has been highlighted by several authors; infection of the phlebotomine by parasites originated from this vertebrate host can already be demonstrated by xenodiagnosis and several cases of feline infection have been reported in endemic regions of several countries such as Brazil, Spain, France, Portugal, Greece, Iran, Israel and Italy. Therefore, the standardization of diagnostic techniques that support the screening and monitoring of such populations becomes of utmost importance. In fact, the use of the IFI and ELISA serological techniques, showing sensitivity and NPV of 100%, confirm the use of such tools in epidemiological surveys for the detection of anti-L. (V.) braziliensis antibodies in domestic cats, and these methodologies are frequently employed in canine surveys showing good results. The serological titers found in this study for Leishmania (V.) braziliensis are similar to those of studies carried out with cats in endemic areas of visceral leishmaniasis in Spain. This similarity shows that the titers can be high even when L. (V.). braziliensis is the etiological agent. It is worth mentioning that these values are significant when compared with those of canine studies carried out in ATL endemic regions. Ultimately, the sample refers to an ATL endemic region located in Brazil, one of the countries with the highest endemicity levels of cutaneous leishmaniasis in the world and, therefore, an important area for the implementation and evaluation of diagnostic techniques for the generation of data on the disease and its possible hosts. Thus, the present study provides information on the occurrence of ATL by Leishmania (V.) braziliensis in domestic cats; demonstrates that the methodologies employed were favorable to the use of such techniques as tools in epidemiological surveys for the diagnosis of feline tegumentary leishmaniasis; and paves the way for further studies on the subject.

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Sero-epidemiological study on Dengue fever virus in humans and camels at Upper Egypt

Veterinary World ◽

10.14202/vetworld.2020.2618-2624 ◽

2020 ◽

Vol 13 (12) ◽

pp. 2618-2624

Author(s):

Mostafa Osman Hussen ◽

Amal S. M. Sayed ◽

Mostafa F. N. Abushahba

Keyword(s):

Dengue Fever ◽

Mosquito Control ◽

Close Contact ◽

Epidemiological Data ◽

Control Measures ◽

Disease Spread ◽

Enzyme Linked Immunosorbent Assay ◽

Risk Of Infection ◽

Cross Sectional ◽

Specific Antibodies

Background and Aim: Dengue fever (DF) is an important mosquito-borne viral zoonosis affecting over 100 countries worldwide and putting about 3.9 billion people at risk of infection. The disease has re-emerged in Egypt since 2011; however, there is a paucity of recent epidemiological data available. Therefore, in this study, we employed a cross-sectional study to determine DF prevalence in humans and camels in Asyut and Sohag Governorates, Egypt, during 2019. Materials and Methods: A total of 91 humans and a similar number of dromedary camels were utilized in this study. Sera were obtained and analyzed for the presence of specific antibodies against DF virus using enzyme-linked immunosorbent assay. Related epidemiological data affecting the disease spread in humans and camels were recorded and statistically analyzed. Results: The seroprevalence of DF in humans and camels was 12.09% and 3.3%, respectively. The disease varied significantly by the species examined as humans were found to be at a higher risk of acquiring the infection compared to camels. Nearly equal odds of exposure (odds ratio [OR]) were seen in the individuals with close contact with camels compared to those without; however, individuals exposed to mosquitoes were at approximately 3 times higher risk of infection (OR=2.95 [95% confidence interval [CI], 0.73-11.93]) compared to individuals who were not exposed to mosquitoes (OR=0.033 [95% CI, 0.084-1.37]). Interestingly, DF seropositivity in camels was significantly related to the presence or absence of symptoms within 2 weeks before sampling (p=0.02) where symptomatic animals had higher odds of exposure (OR=19.51 [95%, 0.97- 392.3]) compared to asymptomatic ones (OR=0.05 [95%, 0.002-1.03]). Conclusion: The current study reports the presence of specific antibodies against dengue virus (DENV) in humans residing within Asyut and Sohag Governorates, Egypt. Furthermore, it provides the first serological evidence of DENV circulation in camels which is alarming. A more comprehensive study is needed; however, this baseline investigation underscores the urgent need for increasing awareness among people residing in the area as well as application of the appropriate mosquito control measures to avoid further spread of the disease.

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