Tested Serum Samples Research Articles

A molecular detection method for HBV pgRNA without RNA extraction based on nucleic acid hybridization

BackgroundEarly diagnosis is critical for patients with chronic hepatitis B. Here, we utilized a sandwich RNA hybridization assay to directly detect HBV pgRNA, thereby avoiding the need for RNA extraction and purification. MethodsWe designed a hybridization cascade reaction on a solid surface using a set of oligonucleotide probes that target several highly conserved regions in pgRNA. The detection performance was validated by concurrently testing serum samples from CHB patients and healthy individuals. ResultsThe optimal detection conditions were: a universal probe coating concentration of 0.003 µg/µl with a coating duration of 2 h; capture probe and detection probe concentrations of 0.1 nM; a hybridization capture duration of 4 h; and an antibody incubation duration of 60 minutes. The sensitivity and specificity were calculated to be 91.47 % and 90.63 %, respectively. ConclusionThis novel detection method is both simple and high-throughput, making it particularly suitable for active CHB infection screening

Diagnosis of invasive aspergillosis in haemato-oncology patients in a routine diagnostic setting.

Invasive Aspergillosis (IA) is a potentially lethal infection in high-risk haemato-oncology patients. Since traditional diagnostic methods have many inherent challenges, Polymerase Chain Reaction (PCR) has been used to diagnose IA. This prospective study evaluated a commercial AsperGenius multiplex real-time PCR for its clinical utility in diagnosing IA compared with galactomannan (GM) testing serum samples from haemato-oncology patients with clinically suspected IA. A total of 107 patients were recruited between April 2022 and March 2023. Serum samples (n=113) collected from those patients for the routine diagnosis by GM Enzyme Linked Immuno-Sorbent Assay (ELISA) were subjected to PCR. The patients were categorised into probable, possible, and no IA based on revised (2020) and previous (2008) European Organization for Research and Treatment of Cancer and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC-MSG) criteria. The performance characteristics of PCR and GM were calculated against the EORTC criteria by combining probable and possible cases as diseased groups. Among the 107 recruited patients, 93 were categorised into probable/possible IA (diseased group) and 14 into no IA group. The PCR was positive in 53 samples from 49 patients. The sensitivity and specificity of single positive PCR and GM were 51.61% [95% confidence interval, 41-62], 92.86% (66.1-99.8) and 26.88% (18.2-37.1), 92.86% (66.1-99.8), respectively. The combination-based strategy (GM and/or PCR positive) exhibited a moderate sensitivity of 62.37% (51-72.2) and a specificity of 85.71% (57.2-98.2). To conclude, the combined strategy of serum GM and/or PCR positivity, along with radiological findings that fulfilled the EORTC/MSG criteria, has improved the diagnosis of probable IA among high-risk haematological patients with clinically suspected IA.

Recombinant 3AB3 nonstructural protein-based indirect ELISA for detection of foot-and-mouth disease virus infection-elicited antibodies in goat.

Foot-and-mouth disease (FMD) is one of the most important animal diseases of economic significance globally. It is a highly infectious and contagious disease of cloven-hoofed animals including sheep and goat. For sero-diagnosis of FMD, recombinant antigen-based assays are considered as alternatives to conventional approaches such as the liquid phase blocking ELISA (LPBE). The early interventions towards control measures cannot be implemented unless the disease gets promptly diagnosed. It is relatively difficult to clinically diagnose FMD in goat due to the usual milder form or unapparent nature of symptoms. Under such situations where clinical samples are not available, demonstration of infection-specific FMD virus (FMDV) antibodies in serum sample may help identifying the animals exposed to the virus in retrospect. Antibody to 3AB nonstructural protein (NSP) has been considered to be the most reliable indicator for FMD diagnosis. The current study extended the earlier designed recombinant 3AB3 protein-based indirect ELISA originally validated on bovine serum samples to testing serum samples of goat. The performance of the indirect ELISA was validated using internationally accepted PrioCHECK® FMDV NS kit. The overall diagnostic sensitivity (DSn) of the indirect ELISA was estimated to be 95.52% (619/648), while the diagnostic specificity (DSp) on naïve and vaccinated animals varied at 98.06% (557/568) and 94.15% (435/462), respectively. In India, where FMD is prevalent and the goat population is so high, this 'in-house' optimized assay can be considered to be an adjunct in sero-epidemiological investigation of FMD in goat.

241 Immunophysiology and performance of broilers supplemented with macroalgal sulfated polysaccharides during a subclinical necrotic enteritis challenge

Abstract This study evaluated the effects of a sulfate polysaccharide extracted from marine algae product on performance, intestinal lesion scores, and mRNA abundance of various tight junction proteins and immune response genes. A total of 600 one-day old male broilers (Ross 708) were allocated to one of four treatment groups (6 replicate floor pens, 25 birds/pen): negative control (NC) group fed a corn-soybean meal diet; positive control (PC) fed NC + 15 ppm Avilamycin and 125 ppm Amprolium, an additive group (AGS) fed NC + Algoguard added at 0.1% of the diet, and (AGH) fed NC + Algoguard added at 0.2% of the diet. To predispose the birds to NE, birds were orally gavaged with 2,000 Eimeria maxima sporulated oocysts on d 14 followed by a dose of approximately 1×108 CFU/mL of C. perfringens on d 19. On d 21, four birds/pen were necropsied for NE lesions and on d 14, 21, and 42 jejunal samples were collected to assess mRNA abundance. Birds and feed were weighed on d 14, 21, 28, and 42 on a per pen basis. Average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were calculated during each feeding phase and adjusted for daily mortality. The data were analyzed using ANOVA (JMP, Pro 16) and significance (P ≤ 0.05) was determined by the LSD test. During d 14-21, 0-21, 0-28, and 0-42, mortality rate and ADFI were significantly less in AGS, AGH, and PC compared with NC. ADG was greater while FCR was significantly less in PC, AGS, and AGH during d 21-28, 0-28, and 0-42 compared with NC (P ≤ 0.05). Lesion severity was also significantly less in AGS, AGH, and PC compared with NC. On d 14, 21, and 42 there were no toxins present in the tested serum samples. Calprotectin concentration was greater in PC and NC on d 21 and 42 compared with the supplemented groups. C. perfringens toxin was not detected in serum samples of any of the four treatment groups. mRNA abundance of CLDN1, IL1β, IL12B, and IL10 was greater in AGS compared with NC on d 14 and 42. ZO1 was significantly greater on d 21 in PC treatment and was less than both AGS and AGH on d 42 (P ≤ 0.05). Compared with all other treatments, mRNA abundance of OCLDN was greater and those of IFN-γ and ZO2 were less in PC, while that of CLDN3 showing no significant difference among all 4 treatments. To conclude, dietary inclusion of this algal product in broiler diets could be considered as a beneficial alternative to antibiotic growth promoters in the context of this challenge model.

Cross-Sectional Study of Q Fever Seroprevalence among Blood Donors, Israel, 2021.

We evaluated Q fever prevalence in blood donors and assessed the epidemiologic features of the disease in Israel in 2021. We tested serum samples for Coxeilla burnetii phase I and II IgG using immunofluorescent assay, defining a result of >200 as seropositive. We compared geographic and demographic data. We included 1,473 participants; 188 (12.7%) were seropositive. The calculated sex- and age-adjusted national seroprevalence was 13.9% (95% CI 12.2%-15.7%). Male sex and age were independently associated with seropositivity (odds ratio [OR] 1.6, 95% CI 1.1-2.2; p = 0.005 for male sex; OR 1.2, 95% CI 1.01-1.03; p<0.001 for age). Residence in the coastal plain was independently associated with seropositivity for Q fever (OR 1.6, 95% CI 1.2-2.3; p<0.001); residence in rural and farming regions was not. Q fever is highly prevalent in Israel. The unexpected spatial distribution in the nonrural coastal plain suggests an unrecognized mode of transmission.

Inter-α-trypsin inhibitor heavy chain 4 (ITIH4) as a compensatory protease inhibitor in hereditary angioedema

BackgroundHereditary angioedema (HAE) is a genetic disorder that manifests as recurrent angioedema attacks, most frequently due to absent or reduced C1 inhibitor (C1-INH) activity. C1-INH is a crucial regulator of enzymatic cascades in the complement, fibrinolytic, and contact systems. Inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4) is an abundant plasma protease inhibitor that can inhibit enzymes in the proteolytic pathways associated with HAE. Nothing is known about its role in HAE. ObjectiveInvestigate ITIH4 activation in HAE, establish it as a potential biomarker, and explore its involvement in HAE-associated proteolytic pathways. MethodsSpecific immunoassays for non-cleaved ITIH4 (Intact ITIH4) and an assay detecting both intact and cleaved ITIH4 (Total ITIH4) were developed. We initially tested serum samples from HAE patients (n=20), ACEI-induced edema patients (ACEI) (n=20), and unknown HAE patients (U-HAE) (n=20). Validation involved an extended cohort of 80 HAE patients (60 type I, 20 type II), including samples taken at attack and quiescent disease periods, as well as 100 healthy controls. ResultsIn 63% of HAE patients, the Intact ITIH4 assay showed lower signals than the Total ITIH4 assay. This difference was not observed in ACEI and U-HAE patients. Western blotting confirmed cleaved ITIH4 in low-Intact ITIH4 samples. In serum samples lacking intact endogenous ITIH4, we observed immediate cleavage of added recombinant ITIH4 suggesting continuous enzymatic activity in the serum. Confirmatory HAE cohort analysis revealed significantly lower intact ITIH4 levels in both HAE type 1 and type 2 patients compared to controls, with consistently low Intact/Total ITIH4 ratios during clinical HAE attacks. ConclusionThe disease-specific low intact ITIH4 levels highlight its unique nature in HAE. The results suggest that ITIH4 may exhibit compensatory mechanisms in HAE, suggesting its utility as a diagnostic and prognostic biomarker. The variations during quiescent and active disease periods raise intriguing questions about the dynamics of proteolytic pathways in HAE.

A declining trend of hepatitis A and hepatitis E at tertiary care hospital in South Gujarat

Objectives: Hepatitis A virus (HAV) and Hepatitis E virus (HEV) both are spread through the fecal-oral route and cause acute viral hepatitis (AVH) and pose a major public health problem in India. This study was done to find out the proportion of positivity of HAV and HEV in patients with AVH and its seasonal trend. Materials and Methods: A retrospective study was carried out at Surat Municipal Institute of Medical Education and Research Medical College, Department of Microbiology, Surat, Gujarat. Result of 3615 blood samples of suspected AVH patients of the past 5 years (January 2018–December 2022) were taken from hospital data records. The enzyme-linked immunosorbent assay method was used to test serum samples for immunoglobulin M (IgM) HAV and IgM HEV antibodies for HAV and HEV, respectively. All samples were evaluated for liver function as well. Results: The positivity of HAV and HEV was 15.13% and 10.26%, respectively. The coinfection rate was 2.07%. HAV and HEV both affected males more than females. Among pregnant females, HEV infection had more positivity (6.77%) than HAV, which had 1.08% positivity. HAV and HEV infections had a seasonal trend, with the highest infection rate in the monsoon. Conclusion: The declining trend of cases of HAV and HEV was found in Surat city of south Gujarat which indicates increased awareness about hepatitis among people and better public health management by the civic authorities.

Development of a rapid LC-MS/MS method for simultaneous quantification of ten commonly used antibiotic drugs in human serum

The use of TDM in clinical practice to monitor the plasma levels of antibiotics administered to critically ill patients is a well-established approach that allows for optimization of the patient's response to drug therapy, considering the characteristics of the drug, the clinical and physiological status of the patient and any peculiar of the pathogen that caused the clinical picture. In our laboratory, we have developed a single LC-MS/MS analysis for dosing the serum concentration of an antibacterial panel composed of eight antibacterial and two selective inhibitors. The method presented used a certified material furnished by a commercial company and was internally validated using the EMA guidelines. The results have shown high sensitivity, precision, and accuracy, a lower matrix effect combined with simple sample preparation and a time-saving procedure. We have evaluated the recovery rate and matrix effect by testing serum samples without pathological index and serum pools obtained from haemolysed, icteric, or lipemic samples. The assay has shown a recovery range between 94% and 101%.

Global evaluation of lineage-specific human papillomavirus capsid antigenicity using antibodies elicited by natural infection.

Human Papillomavirus (HPV) type variants have been classified into lineages and sublineages based upon their whole genome sequence. Here we have examined the specificity of antibodies generated following natural infection with lineage variants of oncogenic types (HPV16, 18, 31, 33, 45, 52 and 58) by testing serum samples assembled from existing archives from women residing in Africa, The Americas, Asia or Europe against representative lineage-specific pseudoviruses for each genotype. We have subjected the resulting neutralizing antibody data to antigenic clustering methods and created relational antigenic profiles for each genotype to inform the delineation of lineage-specific serotypes. For most genotypes, there was evidence of differential recognition of lineage-specific antigens and in some cases of a sufficient magnitude to suggest that some lineages should be considered antigenically distinct within their respective genotypes. These data provide compelling evidence for a degree of lineage specificity within the humoral immune response following natural infection with oncogenic HPV.

Investigation of Reproductive Failure in Buffaloes at a Farm of Itarsi Tehsil in Madhya Pradesh in India for Detection of Antibodies to Brucella Species Organisms by Rose Bengal Test and Infectious Bovine Rhinotracheitis Virus by Indirect Enzyme-linked Immunosorbent Assay

Background: Reproductive failures due to abortion in buffaloes are a major cause of concern to livestock owners that cause economic losses. Brucellosis (bacterial disease) and infectious bovine rhinotracheitis (viral disease), both infectious diseases in buffaloes are implicated in abortions in India. Methods: The investigated buffalo farm experienced a few cases of abortions in pregnant animals in the late trimester. Blood samples were collected aseptically from individual animals without anticoagulants. After clotting of the blood, extracted serum samples were clarified and tested in Rose Bengal test and indirect enzyme-linked immunosorbent assay for the serological diagnosis of brucellosis and infectious bovine rhinotracheitis. Result: Out of 147 buffalo serum samples tested by using the Rose Bengal test, a total of 27 buffalo serum samples (18.36%) tested positive for the presence of agglutinating antibodies against Brucella species. None of the tested serum samples had detectable levels of antibodies against the infectious bovine rhinotracheitis virus in an indirect enzyme-linked immunosorbent assay.

Anti-carbamylated protein antibodies drive AEC II toward a profibrotic phenotype by interacting with carbamylated TLR5.

This study looked at the role of anti-carbamylated protein (anti-CarP) antibodies in contributing to lung fibrosis in CTD-associated interstitial lung disease (ILD) in an autoantigen-dependent manner. ELISA was used to test serum samples, including 89 from the CTD-ILD group and 170 from the non-CTD-ILD group, for anti-CarP levels. Male C57BL/6 mice were used for the pulmonary fibrosis model and anti-CarP treatment in vivo (n = 5) and patient serum-derived or commercialized anti-CarP was used for cell treatment. We identified the carbamylated membrane protein via immunofluorescence (IF) and co-immunoprecipitation followed by mass spectrometry (MS) analysis. Quantitative RT-PCR, IF and western blot were performed to explore the antigen-dependent role of anti-CarP. A native electrophoretic mobility shift assay and MS analysis were used to verify direct interaction and carbamylation sites. A significantly higher serum anti-CarP level was observed in CTD with ILD than without ILD. In vivo, intrapulmonary delivery of anti-CarP induces epithelial-mesenchymal transition (EMT) and microfibrotic foci. Carbamylation was enriched in type II alveolar epithelial cells (AEC II). A novel carbamylated membrane receptor, specifically recognized by anti-CarP, was identified as toll-like receptor 5 (TLR5). We found anti-CarP induces the nuclear translocation of NF-κB and downstream events, including EMT and expression of inflammatory cytokines in AEC II, which were reversed by TLR5 blocking or TLR5 knockdown. Moreover, up to 12 lysine carbamylation sites were found in TLR5 ectodomain, allowing the interaction of anti-CarP with carbamylated TLR5. Overall, we found anti-CarP drives aberrant AEC II activation by interacting with carbamylated TLR5 to promote ILD progression.

Improvement of laboratory testing services by implementation of quality assurance scheme

Introduction: The National AIDS Control Organization (NACO), Government of India and the Uttar Pradesh State AIDS Control Society (UPSACS) established the State Referral Laboratory (SRL) in the Department of Microbiology, Motilal Nehru Medical College, Prayagraj for HIV testing and monitoring of linked HIV Counselling and Testing Services (HCTS) in Uttar Pradesh.Methods: This is a retrospective study conducted from 2008 to 2021. In this evaluation period 10144 serum samples (9580 HIV negative, 555 HIV positive and 9 discordant) were received for retesting at SRL. The Quality Control serum samples received from testing sites consisted of 5% negative and 20% positive from all tested samples collected in the first seven days in the External Quality Assurance Scheme (EQAS) quarter month i.e. January, April, July and October. All samples were tested using rapid diagnostic kits procured by NACO/UPSACS with NACO testing strategy. All linked centres with SRL received 4 coded serum samples for proficiency testing (PT) which were tested similarly.Results: Of 10144 serum samples, 99.92% reported correct results and 0.08% reported discrepancy due to various issues. Similarly in the proficiency testing programme, of 4072 samples tested between 2010 to 2021 by testing sites, 4061 (99.07%) reported concordant results and the remaining14 (0.34%) samples reported indeterminate results. Of the 4072 samples, 14 shows discordant results by three different rapid tests based on different principles. Hands on training were provided for technicians who reported indeterminate results in PT or retesting.Conclusion: The tremendous increase in quality testing at peripheral centrally linked centres increase the reliability of HIV diagnosis at ground level. The study also concluded that continuous monitoring and mentoring of technicians of the diagnostic laboratories under EQAS improves their quality for HIV diagnosis.

Detection of anti-premembrane antibody as a specific marker of four flavivirus serocomplexes and its application to serosurveillance in endemic regions

ABSTRACT In the past few decades, several emerging/re-emerging mosquito-borne flaviviruses have resulted in disease outbreaks of public health concern in the tropics and subtropics. Due to cross-reactivities of antibodies recognizing the envelope protein of different flaviviruses, serosurveillance remains a challenge. Previously we reported that anti-premembrane (prM) antibody can discriminate between three flavivirus infections by Western blot analysis. In this study, we aimed to develop a serological assay that can discriminate infection or exposure with flaviviruses from four serocomplexes, including dengue (DENV), Zika (ZIKV), West Nile (WNV) and yellow fever (YFV) viruses, and explore its application for serosurveillance in flavivirus-endemic countries. We employed Western blot analysis including antigens of six flaviviruses (DENV1, 2 and 4, WNV, ZIKV and YFV) from four serocomplexes. We tested serum samples from YF-17D vaccinees, and from DENV, ZIKV and WNV panels that had been confirmed by RT–PCR or by neutralization assays. The overall sensitivity/specificity of anti-prM antibodies for DENV, ZIKV, WNV, and YFV infections/exposure were 91.7%/96.4%, 91.7%/99.2%, 88.9%/98.3%, and 91.3%/92.5%, respectively. When testing 48 samples from Brazil, we identified multiple flavivirus infections/exposure including DENV and ZIKV, DENV and YFV, and DENV, ZIKV and YFV. When testing 50 samples from the Philippines, we detected DENV, ZIKV, and DENV and ZIKV infections with a ZIKV seroprevalence rate of 10%, which was consistent with reports of low-level circulation of ZIKV in Asia. Together, these findings suggest that anti-prM antibody is a flavivirus serocomplex-specific marker and can be employed to delineate four flavivirus infections/exposure in regions where multiple flaviviruses co-circulate.

Virus Neutralization Test for Detecting and Quantifying Serum-Neutralizing Antibodies to Epizootic Hemorrhagic Disease Virus (EHDV) (Serotypes 1, 2, and 4-8).

The virus neutralization test (VNT) is a functional immunoassay which detects the presence and quantity of neutralizing antibodies. It is a highly sensitive and specific test. As with most neutralization assays, the EHDV VNT does not react with all virus-targeting antibodies, but specifically with those antibodies that bind to VP2, the outermost capsid structural protein of the virus. The interaction between VP2 and neutralizing antibodies can block EHDV cell binding, neutralizing its infectivity. The detection and quantification of neutralizing antibodies are indicative of how protected an animal is against reinfection. The EHD VNT can therefore be a useful tool to monitor the efficacy of a vaccination campaign. VP2 is also the main determinant of EHDV serotype specificity, and so EHDV-neutralizing antibodies which target VP2 are also serotype-specific. Throughdetecting and quantifying neutralizing antibodies, the VNT can discriminate the EHDV serotype responsible for an infection and provides insights into the time of infection. It is considered the gold standard test for identifying and quantifying antibodies against EHDV serotypes present in test serum samples. The assay is performed in vitro and is based on inhibition of virus infectivity in the presence of neutralizing antibodies. A neutralizing antibody titer is determined through the presence or absence of cytopathic effect in a cell monolayer. The VNT is a relatively inexpensive assay using standard laboratory equipment; however, to perform the assay, cell cultures, significant time, intensive labor, and technical skill are required.

Epizootic Hemorrhagic Disease Agar Gel Immunodiffusion Assay.

Agar gel immunodiffusion assay (AGID) is a laboratory test which detects specific antigen-antibody interactions by the development of visible precipitation lines in a semisolid matrix. Here we describe the preparation of agar gel plates, the method to test serum samples by AGID for the presence of EHDV antibodies, and the interpretation of test results. This test has known cross-reactivity to bluetongue antibodies; therefore positive samples by this assay require additional confirmatory testing; generally, its use should be limited to healthy animal attestations where required.

Autoantibody Recognition of Natural and Homocysteinylated Alpha-1 Antitrypsin: Indirect Enzyme-Linked Immunosorbent Assay (ELISA) Quantification in Sera.

In this chapter, indirect enzyme-linked immunosorbent assays (ELISAs) to quantitatively measure autoantibodies directed to human natural and homocysteinylated alpha-1 antitrypsin (anti-AATA and anti-HAATA, respectively) in serum are described. The illustrated ELISA protocols are slightly different, since the two protein forms have different biochemical features and, consequently, different affinity for the matrix (polystyrene microplate wells), so that specific experimental conditions have to be performed for the quantification of the serum antibody recognition.These procedures can be carried out to evaluate the anti-AATA and the anti-HAATA levels, testing serum samples, for research use.

Seroprevalence of serovars of pathogenic leptospira in dogs and red foxes (Vulpes Vulpes) from bosnia and herzegovina

Abstract The aim of this study was to examine the seroprevalence of Leptospira spp. in dogs and red foxes in the entity of the Republic of Srpska, Bosnia and Herzegovina, after heavy rainfall and floods in 2014 and for the two years thereafter. The seroepidemiological study involved testing serum samples from dogs (n = 98) and foxes (n = 112) using MAT (microscopic agglutination test). Antibodies to at least one Leptospira spp. serovar were found in 52.04% of the tested dogs. The dog seroprevalence in 2014 (81.25%) was significantly higher than in 2015 (51.42% p &lt;0.0001) and 2016 (22.5% p&lt;0.05). The highest seroprevalences were for serovars Australis (76.47%), Bratislava (70.58%), Sejroe (66.67%) and Autumnalis (45.09%). Antibodies to at least one Leptospira spp. serovar were detected in 34.82% of the examined red foxes. In 2015, the fox seroprevalence was significantly higher (52.94%) than in 2016 (6.82%) (p &lt;0.0001). The highest seroprevalences were for serovars Sejroe (64.10%), Bratislava (48.72%), Australis (43.59%) and Bataviae (25.64%). The high seroprevalence of Leptospira spp. in dogs and foxes determined during this study indicates the importance of these carnivores in maintaining leptospirosis in the study area, and the potential risk of infection for humans and other animal species that come into contact with these canids. The results obtained indicate that heavy rainfall and intense floods can result in increased Leptospira spp. infection in these canids.

Detection of Brucella melitensis in milk and serum samples of goats by serological and molecular techniques

The present investigation was planned for the detection of brucellosis in goats using serological and molecular techniques. A total of 500 clinical samples (250 milk and 250 serum) of goats were collected. All the milk samples were screened by Milk Ring Test and Enzyme-Linked Immunosorbent Assay and serum samples with i-ELISA. Further, the positive milk and serum samples were subjected to 16SrRNA and OMP-31 PCR assays. Results showed the seropositivity of brucellosis was 34.8% and 16% from milk and serum samples of goats by ELISA, respectively and 2.8% by MRT. The results of 16SrRNA PCR detected B. abortusS19, in 32 (36.78%) milk samples and 10 (25%) serum samples by showing an amplicon of 1412 bp. Similarly, the OMP-31 PCR assay tested positive for B. melitensis Rev1, in 22 (25.28%) milk and 05 (12.5%) serum samples by showing an amplicon of 720 bp. Hence, this study is helpful for the detection of brucellosis in goats by using milk and serum samples. The study has generated evidence on the distribution of Brucella melitensis in milk and demonstrated the need to aware people about the importance of boiling milk before consumption in household and thus reduce the risk of infection in human beings.

SARS-CoV-2 Serological Investigation of White-Tailed Deer in Northeastern Ohio.

Coronaviruses are known to cross species barriers, and spill over among animals, from animals to humans, and vice versa. SARS-CoV-2 emerged in humans in late 2019. It is now known to infect numerous animal species, including companion animals and captive wildlife species. Experimental infections in other animals have established that many species are susceptible to infection, with new ones still being identified. We have developed an enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to SARS-CoV-2 nucleocapsid (N) and spike (S) proteins, that is both sensitive and specific. It can detect S antibodies in sera at dilutions greater than 1:10,000, and does not cross-react with antibodies to the other coronaviruses tested. We used the S antibody ELISA to test serum samples collected from 472 deer from ten sites in northeastern Ohio between November 2020 and March 2021, when the SARS-CoV-2 pandemic was first peaking in humans in Ohio, USA. Antibodies to SARS-CoV-2 were found in serum samples from every site, with an overall positivity rate of 17.2%; we further compared the viral neutralizing antibody titers to our ELISA results. These findings demonstrate the need to establish surveillance programs to monitor deer and other susceptible wildlife species globally.

Variation in antibody titers determined by Abbott and Roche Elecsys SARS-CoV-2 assays in vaccinated healthcare workers

SARS-CoV-2-specific antibody measurement is important for evaluating COVID-19 vaccine efficacy. We quantified and compared anti-spike (S) antibodies using different commercial immunoassays. We tested serum samples from 70 SARS-CoV-2-naive health care workers 2 weeks after vaccination with a single dose of BNT162b2, 2 and 4 weeks, and 3 months after the second dose of BNT162b2. The following quantitative assays were used: Roche Elecsys Anti-SARS-CoV-2 S (Roche-S), Abbott SARS-CoV-2 IgG II Quant [Abbott-IgG(S)], and Abbott SARS-CoV-2 IgM (Abbott-IgM). All samples tested positive for Roche-S and Abbott-IgG antibodies after the second dose, with 83.6% Abbott-IgM positive rate. Roche-S and Abbott-IgG(S) correlated significantly in all samples (r = 0.920, p < 0.0001), and the Roche-S and Abbott-IgG(S) assay showed a strong correlation with each other at each time point after vaccination. Roche-S and Abbott-IgG(S) antibody titers were correlated with age; their rate of decline was age-dependent in males but not in females. Abbott-IgG(S) antibody titers decreased from 2 weeks after the second dose. Roche-S antibody titers peaked 2 weeks after the second dose in 76.2% of the participants; the titers recovered 3 months post-vaccination after declining at week 4 in 40.7% of the participants. The concordance between Roche-S and Abbott-IgG(S) antibody titers over time was 47.5%. Most participants presented significantly high Roche-S and Abbott-IgG(S) antibody titers after immunization. Some measurements were inconsistent with titer changes between these assays, possibly because of differences in the immunoglobulin-specificity of the kits.