Antigen Detection Kit Research Articles

Comparison of analytical sensitivity of the eight rapid antigen detection kits for detecting SARS-CoV-2 virus.

Comparison of analytical sensitivity of the eight rapid antigen detection kits for detecting SARS-CoV-2 virus.

Epidemiology of hepatitis b virus, hepatitis C virus and human immunodeficiency virus co-infection among assymptomatic persons resident in Alex Ekwueme federal university Ndufu-alike

Based on their epidemiology, Hepatitis B virus (HBV), Hepatitis C virus (HCV) and Human Immunodeficiency virus (HIV), share the same routes of transmission and risk factors for infection. This study was conducted to determine the epidemiology of HBV, HCV, HIV co-infection among residents of Alex Ekwueme Federal University Ndufu- Alike, Ebonyi State Nigeria who are mostly young adults. Three Hundred and Eighty-Four participants were enlisted for this study. Blood samples were collected and tested for presence of Hepatitis B surface antigen (HBsAg), Anti-HCV antibodies and HIV antibodies using first response antigen detection kits for HBV and HCV as well as Determine and StatPak kits for HIV. Data was analyzed using descriptive statistics, Chisquare was used to test the associations. Statistical significance was taken at P ˂ 0.05. Data was analyzed using SPSS version 20.0. Results obtained from this study showed that the mean age of the participants was 24 years (SD: 5.343). The prevalence for HCV and HBV was 8.85% and 10.86% respectively. The occurrence of HBV and HCV co-infection was statistically non- significant (p 0.50). However, the prevalence of HBV was statistically significant (p = 0.012) The prevalence of HIV was 5.99%. A total of 5 (1.30%) had concomitant HBV, HCV and HIV infections. Also, 11 (2.86%) had HBV/HIV co-infection, 8(2.08%) had HCV/HIV co-infection while 5(1.30%) had HBV/HCV co-infections. All the participants were asymptomatic. This study demonstrated high prevalence of HBV, HCV and HIV and provides the first epidemiologic data on the prevalence of these viral infections among the population within the geographic region studied. To reduce the prevalence of the viral infections among the populations, preventive strategies should be developed and implemented. Also, further studies should be conducted to elucidate the epidemiological pattern of HIV, HCV and HBV concomitant infections in other States within south-eastern Nigeria.

Potential Diagnostic and Prognostic Biomarkers for Adenovirus Respiratory Infection in Children and Young Adults.

Human Adenoviruses (HAdV) are known to be potentially associated with strong inflammatory responses and morbidity in pediatric patients. Although most of the primary infections are self-limiting, the severity of clinical presentation, the elevation of the white blood cell count and inflammatory markers often mimic a bacterial infection and lead to an inappropriate use of antibiotics. In infections caused by HAdV, rapid antigen detection kits are advisable but not employed routinely; costs and feasibility of rapid syndromic molecular diagnosis may limit its use in the in-hospital setting; lymphocyte cultures and two-sampled serology are time consuming and impractical when considering the use of antibiotics. In this review, we aim to describe the principal diagnostic tools and the immune response in HAdV infections and evaluate whether markers based on the response of the host may help early recognition of HAdV and avoid inappropriate antimicrobial prescriptions in acute airway infections.

Rapid antigen detection kit for the diagnosis of SARS-CoV-2 - are we missing asymptomatic patients?

PurposeTo determine the utility, diagnostic accuracy, sensitivity, specificity, and negative predictive value of the laboratory based Covid-19 antigen detection test (Coris Bio- Concept, Gembloux, Belgium) for the diagnosis of SARS-CoV-2 in a tertiary care hospital among symptomatic and asymptomatic patients. MethodsThe nasopharyngeal swab samples were collected from the symptomatic patients and their contacts. The diagnostic accuracy of this antigen kit was determined in comparison to SARS-CoV-2 real-time reverse transcriptase (RT-PCR). ResultsA total of 825 patients fulfilling the inclusion criteria were included in the study; RT-PCR and antigen detection was performed simultaneously for 484 samples to determine the sensitivity and specificity of the test. The overall specificity and sensitivity was 99.32% and 71.96% respectively. Also, 3.7% of the asymptomatic patients who were negative by RAT were detected positive by RT-PCR. ConclusionThis rapid antigen test (RAT) was sensitive in the symptomatic patients presenting during the initial phase of the illness. Since, majority of the SARS-CoV-2 patients are asymptomatic and considering the huge population, the testing strategy formulated by Indian Council of Medical Research (ICMR) at the national level was cost effective. Thus, Ag-RDTs could play a pivotal role in early diagnosis, policy making and surveillance of the SARS-CoV-2.

Evaluation of Two Rapid Antigenic Tests for the Detection of SARS-CoV-2 in Nasopharyngeal Swabs.

(1) Background: In the current context of the COVID-19 crisis, there is a need for fast, easy-to-use, and sensitive diagnostic tools in addition to molecular methods. We have therefore decided to evaluate the performance of newly available antigen detection kits in “real-life” laboratory conditions. (2) Methods: The sensitivity and specificity of two rapid diagnostic tests (RDT)—the COVID-19 Ag Respi-Strip from Coris Bioconcept, Belgium (CoRDT), and the coronavirus antigen rapid test cassette from Healgen Scientific, LLC, USA (HeRDT)—were evaluated on 193 nasopharyngeal samples using RT-PCR as the gold standard. (3) Results: The sensitivity obtained for HeRDT was 88% for all collected samples and 91.1% for samples with Ct ≤ 31. For the CoRDT test, the sensitivity obtained was 62% for all collected samples and 68.9% for samples with Ct ≤ 31. (4) Conclusions: Despite the excellent specificity obtained for both kits, the poor sensitivity of the CoRDT did not allow for its use in the rapid diagnosis of COVID-19. HeRDT satisfied the World Health Organization’s performance criteria for rapid antigen detection tests. Its high sensitivity, quick response, and ease of use allowed for the implementation of HeRDT at the laboratory of the University Hospital of Liège.

Epidemiological Risk of Dirofilariasis in the Voronezh Region

Background. Dirofilariasis is a vector-borne helminthiasis that tends to expand spatial boundaries in areas with temperate and cold climates. In the Voronezh oblast, located in the Central Black Earth Region of the Russian Federation there were previously isolated reports of cases of dirofilariasis in humans and dogs, but this issue was not specifically studied.Aims. To determine the degree of infection of dogs with Dirofilaria immitis and Dirofilaria repens in the Voronezh oblast in order to determine the level of epidemiological risk.Materials and methods. For seven years, targeted work was carried out to study the spread of different types of dirofilariae in dogs in the Voronezh region. Blood from 3 498 dogs of different breeds, ages, conditions of keeping and household use was examined. Dirofilaria larvae were counted using the Fuchs-Rosenthal camera. The type of dirofilaria larvae isolated from the blood of dogs was determined by the histochemical method. The antigen of the imaginal form of D. immitis was detected using a chromatographic test system the ImmunoRun Antigen Detection Kit Caninae Heartworm Biogal chromatographic test system (Israel). Statistical processing of the material was carried out in the Microsoft Excel 2010 program. Studies were carried out with the consent of animal owners and in accordance with the European Convention for the Protection of Vertebral Animals used for experimental and other scientific purposes (Strasbourg, 1986).Results. As a result of the conducted studies, it was found that in the Voronezh oblast, the average infection of domestic dogs (Canis familiaris) with dirofilariasis is 14.14 ± 0.31 %. The indicator depends on the conditions of keeping animals and makes 27.15 % in stray dogs, 25.26 % – in service dogs and 10.54 % – in apartment dogs. In service dogs, the species D. repens occurs in 52.39 % of cases, D. immitis – in 42.95 %, mixtinvasia – in 4.80 % of cases. In stray dogs, the species D. repens prevails (80.10 %). The second type of D. immitis was established in 10.0 % of cases. At the same time, both types were also established in 10.0 % of cases. The maximum number of cases of dirofilariasis occurs in urban dogs (65.87 %), which is due to the high density of their population and close contact with the vector of transmission in urbanized areas. The seasonal dynamics of infestation is determined by the year-round detection of cases with a peak in October (46.77 %). The number of cases of dirofilariasis increases with age, in dogs from one to six years old it reaches maximum of 63.26 %. There is an epidemiological risk of dirofilariasis in the Voronezh oblast. This is due to the existence and active functioning of synanthropic and natural foci of invasion on the territory of the Voronezh oblast.

Laboratory Evaluation of Hepatitis C Virus Infection in Patients Undergoing Hemodialysis from North East India

Subjects undergoing hemodialysis have enhanced vulnerability to hepatitis C virus (HCV) infection due to invasive procedures and poor infection control practices. Early detection and treatment are essential to prevent cross-infection and mortality/morbidity. However, common use anti-HCV antibody tests lack the necessary accuracy, and alternative tests (e.g. core antigen detection kits) which are available need to be examined as a viable alternative. A total of 270 continuous serum samples were collected from patients undergoing dialysis within 15 months of study period. Sequentially, multiple tests were performed - immunochromatography-based rapid test, third-generation ELISA i.e. (anti-HCV antibody detection), fourth-generation ELISA (HCV antigen-antibody combined detection assay), and HCV RNA quantitative real time polymerase chain reaction (qPCR) assay. Diagnostic parameters of serological kits were compared in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and so on. Statistical Package for the Social Sciences was used. HCV-combined core antigen-antibody assays performed better than other serological assays in reference to the gold standard HCV RNA. This fourth-generation assay yielded a Kappa value of 0.947 compared with the value of 0.747 and 0.619 for anti-HCV ELISAand rapid detection test. Other parameters such as sensitivity, specificity, PPV, NPV, and so on were also better for fourth-generation ELISA compared with third-generation ELISA and other serological assays. HCV RNA was negative in 7.3% of anti-HCV-positive patients and was detected in 11.4% of anti-HCV ELISA-negative patients. In about 1.6% of HCV RNA-positive cases, fourth-generation ELISA was negative and had low HCV viral load (650 IU/ml and below). Fourth generation ELISA detected additional 7.4% HCV positive cases (compared to third generation kits) and upon cost effective analyis, additional cost to be bear for the better detection (by fourth generation kit) was found to be only INR 27 per 1% increased case detection. In resource scant setup, screening and follow-up of patients undergoing hemodialysis can be performed by fourth-generation HCV ELISA (antigen-antibody combined assay) instead of the current practice of anti-HCV antibody ELISA. Better yield in detection rate will compensate for slight addition to costs.

Evaluation of five Legionella urinary antigen detection kits including new Ribotest Legionella for simultaneous detection of ribosomal protein L7/L12

Urinary antigen tests are a widely used rapid diagnostic method for Legionella pneumonia. However, conventional urinary antigen tests are unable to detect anything other than Legionella pneumophila serogroup 1. The Ribotest Legionella (Ribotest) can detect all serogroups by using antibodies recognizing L. pneumophila ribosomal protein L7/L12 in addition to the conventional L. pneumophila serogroup 1 lipopolysaccharide. The aim of this study was to evaluate the performance of Ribotest against conventional urinary antigen tests, including the detection of Legionellaceae other than L. pneumophila. We investigated the detection sensitivity of various kits using in-vitro culture-soluble antigen extracts of ATCC strains and 22 clinical isolates collected from multiple medical facilities in the Kinki region of Japan. For L. pneumophila serogroup 1, four kits, including Ribotest, had a detection sensitivity of 105 CFU/mL, with only Check Legionella having a sensitivity of 106 CFU/mL. L. pneumophila non-serogroup 1 and Legionellaceae of other species were undetectable by the four conventional kits, whereas Ribotest could detect them with a sensitivity of 105–108 CFU/mL. The Ribotest was also able to detect other species such as Legionella hackeliae, Legionella feeleii, Legionella anisa, Fluoribacter bozemanae, and Fluoribacter dumoffii, but the detection sensitivity of L. hackeliae and L. feeleii was 108 CFU/mL, which was much lower than that of the other strains. The Ribotest has high potential to be applied as a rapid diagnostic method for pneumonia caused by other species of Legionella and Fluoribacter.

Clinical Application of a New SARS-CoV-2 Antigen Detection Kit (Colloidal Gold) in the Detection of COVID-19.

The precise diagnosis of COVID-19 is of outmost importance in order to effectively treat patients and prevent SARS-CoV-2 transmission. Herein, we evaluated the sensitivity and specificity of the COVID-19 Antigen Detection Kit (Colloidal Gold—CG) compared with PCR in nasopharyngeal and nasal samples. A total of 114 positive and 244 negative nasopharyngeal specimens confirmed by PCR were used in this comparative study. When the PCR positive Cycle Threshold (Ct) value was ≤25, CG sensitivity was 100%. When the PCR positive Ct value was ≤33, CG sensitivity was 99%. When the PCR positive Ct value was ≤40, CG sensitivity was 89.47%. Regarding nasal swabs, a total of 109 positive and 250 negative specimens confirmed by PCR were used. When the PCR positive Ct value was ≤25, CG sensitivity was 100%. When the PCR positive Ct value was ≤33, CG sensitivity was 96.12%. When the PCR positive Ct value was ≤37, CG sensitivity was 91.74%. Specificity was above 99% regardless of the Ct value of PCR positivity for both nasopharyngeal and nasal specimens. Overall, the CG showed high sensitivity and specificity when the PCR Ct value was less than 33. Therefore, CG can be used for screening early in the disease course. Confirmatory PCR is essential when a false negative result is suspected.

Application of an AlphaLISA method for rapid sensitive detection of African swine fever virus in porcine serum.

Infection with African swine fever virus (ASFV) causes an acute and highly lethal hemorrhagic disease that has been responsible for huge economic losses in China. To exactly detect the antigen of ASFV, we established a rapid, no-wash, one-step sandwich-type immunoassay based on the amplified luminescent proximity homogenous assay-linked immunosorbent assay (AlphaLISA) using two monoclonal antibodies (mAbs) M-5 and M-6 against ASFV p72. ASFV p72 in samples was captured by biotinylated mAb M-5 connected to the donor bead surface via streptavidin and "sandwiched" by mAb M-6 which was coated onto the acceptor bead. Efficacy and sensitivity trials revealed that the AlphaLISA could detect ≥0.78 ng/ml of purified p72 and with a linear range of 0.78-100 ng/ml. The AlphaLISA was specific for ASFV and did not cross-react with other common pathogenic porcine viruses. Compared with RealPCR ASFV DNA test and ASFV antigen detection kit, the sensitivity of the AlphaLISA evaluated in 60 porcine serum samples was 93% and 100%, respectively. The specificity was 100% and 91.7%, respectively. This study presents a good laboratory diagnostic tool for sensitive and efficient detection of ASFV in porcine serum. KEY POINTS: • MAbs M-5 and M-6 recognized various epitopes of ASFV p72. • The established ASFV p72 AlphaLISA showed well specificity, high sensitivity, and satisfied correlation coefficient.

Misdiagnosis of SARS-CoV-2: A Critical Review of the Influence of Sampling and Clinical Detection Methods.

SARS-CoV-2 infection has generated the biggest pandemic since the influenza outbreak of 1918–1919. One clear difference between these pandemics has been the ability to test for the presence of the virus or for evidence of infection. This review examined the performance characteristics of sample types via PCR detection of the virus, of antibody testing, of rapid viral antigen detection kits and computerised tomography (CT) scanning. It was found that combined detection approaches, such as the incorporation of CT scans, may reduce the levels of false negatives obtained by PCR detection in both symptomatic and asymptomatic patients, while sputum and oral throat washing sample types should take precedence over swabbing when available. Rt-PCR assays for detection of the virus remain the gold-standard method for SARS-CoV-2 diagnosis and can be used effectively on pooled samples for widespread screening. The novel Oxford antibody assay was found to have the highest sensitivity and specificity of four currently available commercial antibody kits but should only be used during a specific timeframe post-symptom onset. Further research into transmission modes between symptomatic and asymptomatic patients is needed. Analysis of the performance characteristics of different sampling and detection methods for SARS-CoV-2 showed that timing of sampling and testing methods used can greatly influence the rate of false-positive and false-negative test results, thereby influencing viral spread.

Highly specific monoclonal antibodies and epitope identification against SARS-CoV-2 nucleocapsid protein for antigen detection tests

SummaryThe ongoing coronavirus disease 2019 (COVID-19) pandemic is a major global public health concern. Although rapid point-of-care testing for detecting viral antigen is important for management of the outbreak, the current antigen tests are less sensitive than nucleic acid testing. In our current study, we produce monoclonal antibodies (mAbs) that exclusively react with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and exhibit no cross-reactivity with other human coronaviruses, including SARS-CoV. Molecular modeling suggests that the mAbs bind to epitopes present on the exterior surface of the nucleocapsid, making them suitable for detecting SARS-CoV-2 in clinical samples. We further select the optimal pair of anti-SARS-CoV-2 nucleocapsid protein (NP) mAbs using ELISA and then use this mAb pair to develop immunochromatographic assay augmented with silver amplification technology. Our mAbs recognize the variants of concern (501Y.V1-V3) that are currently in circulation. Because of their high performance, the mAbs of this study can serve as good candidates for developing antigen detection kits for COVID-19.

Considerations in Real-time Reverse Transcription Polymerase Chain Reaction (rRT-PCR) for the Detection of SARS-CoV-2 from Nasopharyngeal Swabs

Coronavirus Disease 2019 (COVID-19) was first reported in December 2019, in the City of Wuhan, China. Within the span of a few weeks, the disease had spread to other regions of China and eventually to different parts of the world. COVID 19 has affected 221 countries and territories around the world, with a total of 121,290,697 positive cases and 2,682,554 deaths as on March 17, 2021. Accurate disease diagnosis (for the SARS-Cov-2 virus and variants), coupled to patient isolation are currently critical strategies in restricting disease spread. Due to lack of time during this pandemic the diagnostics assays were not adequately validated. Infected individuals at times could potentially be missed by real-time reverse transcription polymerase chain reaction (rRT-PCR) for SARS-CoV-2 tests due to incorrect/inefficient sampling procedure, low limit of detection and epidemiology of the virus. rRT-PCR test results should be interpreted in conjunction with clinical examination and Computed Tomography (CT), particularly in suspected symptomatic individuals or those with epidemiological history of contact with known COVID-19 cases. Considering the above-mentioned constraints, the current scenario demands rapid and point-of-care tests for detection of SARS-CoV-2 in remote locations. To date, there is no reliable commercially available antigen detection kit. The infected subjects reveal low levels of antibodies against SARS-CoV-2 through the early period of infection. In addition, techniques such as, Digital RT-PCR technology and isothermal RNA amplification with electrochemical biosensors are some of the new technologies currently being developed to provide sensitive and specific SARS-Cov-2 antigen detection. The newly reported variant, SARS-CoV-2 VUI 202012/01 may not influence diagnostic outcomes as worldwide most PCR assays use two or more (including RdRp/ E/ N) reliable gene targets, besides S gene.

Evaluation of fecal immunoassays for canine Echinococcus infection in China.

Human echinococcosis is present worldwide but it is in China that disease prevalence is the highest. In western China, especially in the Tibetan Plateau, the burden of echinococcosis is the most important. Dogs are a major definitive host of Echinococcus and monitoring the presence of Echinococcus worms in dogs is therefore essential to efficiently control the disease. Detection kits based on three different technologies including sandwich ELISA, (indirect) ELISA, and gold immunodiffusion, are currently marketed and used in China. The objective of this work was to assess the efficacy of these kits, in particular with respect to sensitivity and specificity. Four fecal antigen detection kits for canine infection reflecting the three technologies were obtained from companies and tested in parallel on 220 fecal samples. The results indicate that the performance is lower than expected, in particular in terms of sensitivity. The best results were obtained with the sandwich ELISA technology. The gold immunofiltration yielded the poorest results. In all cases, further development is needed to improve the performance of these kits which are key components for the control of echinococcosis.

English

BACKGROUND India is among one of the major tuberculosis (TB) endemic countries of the world. The Centers for Disease Control and Prevention (CDC) guidelines mandate early species identification of M. tuberculosis complex as an effective countermeasure. The conventional culture method, which is the ‘gold-standard’ technique of mycobacterial isolation is time consuming, while the newer, automated, liquid medium-based culture systems like BACT / ALERT 3D have considerably shorter detection time and greater sensitivity. Other than isolation it is also important to differentially identify Mycobacterium tuberculosis complex (MTBC) from nontuberculous mycobacteria (NTM). As MPT 64 antigen is specific for MTBC and can be detected with considerable accuracy it can be used as a tool to differentiate between MTBC and NTM. METHODS 200 samples (sputum, cerebrospinal fluid-CSF, pleural fluid etc.) in total were collected from clinically suspected smear negative patients. Each sample was inoculated both in L-J media and BACT / ALERT 3D system. Those samples which showed growth were further differentiated into MTBC and NTM both by conventional biochemical tests and MPT64 antigen detection kit test. RESULTS Out of the 200 samples, 30 produced growths. Lowenstein-Jensen (L-J) media detected 12 (40 %) and BACT / ALERT 3D system detected 26 (86.67 %) of the isolates. Among the 30 isolates, 18 (60 %) were MTBC and 12 (40 %) were NTM. Furthermore, L-J media detected 44.4 % and BACT / ALERT 3D system detected 88.9 % out of 18 MTBC isolates while among the 12 NTM isolates L-J media detected 33.33 % and BACT / ALERT 3D system detected 83.33 %. Mean detection time for MTBC was 46.5 days by L-J media and 20.8 days by BACT / ALERT 3D system. Mean detection time for NTM was 24.5 days by L-J media and 9.86 days by BACT / ALERT 3D system. Contamination rate in this study was 12 % in L-J media and 3 % in BACT / ALERT 3D system. We also found that for sensitivity, specificity, positive predictive value, negative predictive value of MPT64 antigen detection kit test was 100 % in our study considering biochemical tests as gold standard. CONCLUSIONS BACT / ALERT 3D system has a very good isolation rate and shorter mean detection time compared to L-J media even from smear negative samples. Also, MPT-64 antigen detection kit test is a very viable option to differentiate between MTBC and NTM. KEYWORDS MTBC, NTM, BACT / Alert 3D, MPT 64 Antigen

Equine rotavirus infection

ABSTRACTThis review briefly describes the virus classification, clinical signs, epidemiology, diagnosis, disinfection, and vaccines related equine group A rotavirus (RVA) infection. Equine RVA is one of the most important pathogens causing diarrhoea in foals. The main transmission route is faecal–oral, and the clinical signs are diarrhoea, fever, lethargy, and anorexia (decreased suckling). Some human RVA rapid antigen detection kits based on the principles of the immunochromatographic assay are useful for the diagnosis of equine RVA infection. The kits are used in daily clinical practice because of their rapidity and ease of handling. Equine RVA is a non-enveloped virus and is more resistant to disinfectants than enveloped viruses such as equine influenza virus and equine herpesvirus. Although amphoteric soaps and quaternary ammonium compounds are commonly used in veterinary hygiene, they are generally ineffective against equine RVA. Alcohol products, aldehydes, and chlorine- and iodine-based compounds are effective against equine RVA. Inactivated vaccines have been used for equine RVA infection in some countries. Pregnant mares are intramuscularly inoculated with a vaccine, and thus their colostrum has abundant antibodies against RVA at the time of birth. According to G and P classification defined in accordance with the VP7 and VP4 genes, respectively, the predominant equine RVAs circulating in horse populations globally are G3P[12] and G14P[12] equine RVAs, but the vaccines contain only the G3P[12] equine RVA strain. Ideally, a G14P[12] equine RVA should be added as a vaccine strain to obtain a better vaccine effect.

Entamoeba histolytica infections in a slum community in Manila, Philippines as detected by stool ELISA.

This study aimed to determine the prevalence of Entamoeba histolytica in BASECO, an urban slum community situated in Manila Harbor, Manila, Philippines using stool enzyme-linked immunosorbent assay (ELISA). It also aimed to determine if age, sex, and geographic location are contributory factors to the prevalence of E. histolytica. Stool samples were collected from 627 urban slum community residents of BASECO. Samples were viewed under light microscopy and the different parasites observed were identified. Stool ELISA was done using E. histolytica II antigen detection kits (TECHLAB®). Using E. histolytica II kits, E. histolytica had a prevalence of 9.09% (5/55) among the microscopically-positive samples for E. histolytica/E. dispar indicating a greater prevalence for the nonpathogenic species. No significant difference was observed in the prevalence of infection across all three variables: age, sex and geographic location. The overall prevalence of E. histolytica in BASECO, Manila, Philippines is 0.797% (5/627) which is lower than previous studies done on estimating the prevalence of E. histolytica using various techniques.

Seroprevalance of infectious diseases among blood donors, a retrospective study in MVJMC&RH in rural Bengaluru

Introduction: Blood transfusion despite being a lifesaving procedure is still posing greatest threat of transmitting infectious diseases like HIV, HBsAg, HCV, Syphilis and Malaria. Even completely tested unit of blood is hazardous. Aim and Objectives: The aim of the study was to study the trend and prevalence of sero-markers among blood donors in MVJMC&RH in Hoskote Rural Bengaluru. Materials and Methods: A retrospective cross-sectional study was performed from Jan 2011 to Dec 2017 in the blood bank attached to MVJMC&RH. All blood donors who donated in blood bank and outdoor camps during the study period were included and data was analyzed. TTIs testing were done with (ELISA) 4th generation kits for HIV I & II, 3rd generation kits of Hepalisa (HBsAg), and microlisa (HCV) kits for hepatitis C virus. Screening for syphilis was done by RPR and Malaria was detected using (antigen detection kits) Advantage pan malaria cards. Results: There were a total of 9092 blood donors during the study period. out of which 8952 (98.46%) were males and 140 (1.53%) were females. 88 (0.96%) cases were positive for sero-markers for TTIs, Among the 88 seropositive cases, 9 cases of HIV (0.09 %), 48 cases of hepatitis B surface antigen HBsAg (0.52%), 7 cases of hepatitis C virus HCV (0.07%), 23 (0.25%), cases with syphilis reactivity and 1 case of malaria (0.01%) were encountered. Conclusions: Sero-prevalence of TTIs showed a downward trend, probably due to strict donor selection criteria, predonation screening and better education and awareness to donors. Keywords: HBV, HCV, HIV, Prevalence, TTI.

Evaluation of rapid antigen detection kit from the WHO Emergency Use List for detecting SARS-CoV-2.

BackgroundCurrently, there are two rapid antigen detection (RAD) kits from the WHO Emergency Use List for detecting SARS-CoV-2.ObjectiveThe Panbio COVID-19 Ag Rapid Test Device was selected to evaluate the performance for detecting SARS-CoV-2.Study DesignAnalytical sensitivity for the detection of SARS-CoV-2 virus was determined by limit of detection (LOD) using RT-PCR as a reference method. Clinical sensitivity was evaluated by using respiratory specimens collected from confirmed COVID-19 patients.ResultsThe LOD results showed that the RAD kit was 100 fold less sensitive than RT-PCR. Clinical sensitivity of the RAD kit was 68.6 % for detecting specimens from COVID-19 patients.ConclusionsThe RAD kit evaluated in the present study shared similar performance with another kit from the WHO Emergency Use List, the Standard Q COVID-19 Ag. Understanding the clinical characteristics of RAD kits can guide us to decide different testing strategies in different settings.

Highly Specific Monoclonal Antibodies Against SARS-CoV-2 Nucleocapsid Antigen for Accurate Diagnosis of COVID-19

The ongoing COVID-19 pandemic is a major global public health concern. Although rapid point of care testing for detecting viral antigen is important for management the outbreak, none of current antigen detection kits provide a reliable diagnosis due to the lack of a specific monoclonal antibody (mAb) against SARS-CoV-2. In our current study, we produced mAbs exclusively react with SARS-CoV-2 and exhibited no cross-reactivity with other human coronaviruses including SARS-CoV. Molecular modeling revealed that the mAbs bound to epitopes present on the exterior surface of the nucleocapsid, encompassing their scope for detecting SARS-CoV-2 in clinical samples. We further selected the optimal pair of anti-SARS-CoV-2 NP mAbs for designing ELISA and immunochromatographic assay. An integrated bioinformatics analysis revealed that our mAbs could comprehensively detect divergent strains of SARS-CoV-2. Due to the high redundancy and absence of cross-reactivity, our newly developed mAbs would be instrumental for developing reliable diagnosis kits for COVID-19.Funding: This work was supported in part by Japan Agency for Medical Research and Development (AMED, Grant number: JP19fk0108110 and JP20he0522001), and by Health Labour Sciences research grant from The Ministry of Health Labour and Welfare.Conflict of Interest: The authors have no conflicts of interest directly relevant to the content of this article. YY, SK, KS and DA is a current employee of Kanto Chemical Co., Inc.Ethical Approval: This study was approved by the Institutional Review Board of Yokohama City University (IRB No. B200800106), and the protocols used in the study were approved by the ethicscommittee.