HBsAg Ultra Research Articles

Serological Evidence of HIV/HBV Co-infection among HIV-infected patients in Onitsha, Anambra State, Nigeria

Research suggests that HIV-infected individuals who have also been co-infected with HBV face a greater risk of HIV progression. Hepatitis B and HIV infections pose serious public health challenges in sub-Saharan Africa. This study examined the possible HBV co-infection with the socio-demographic traits of HIV-infected individuals attending the HIV clinic at a referral specialist mission hospital in Onitsha, Anambra State, Nigeria. Two hundred and twenty (220) HIV-infected individuals gave consent to participate in the study. Between March 2022 and October 2022, blood samples (about 5ml) were aseptically collected during routine investigations into sterile EDTA bottles, and plasma samples were obtained by centrifugation. These samples were tested for HBsAg using a Monolisa HBsAg ULTRA kit (Bio-Rad, USA). CD4 counts were measured using the Partec CyFlow. Plasma viral loads (PVL) were also determined using the Abbott Real-Time HIV-1 Assay US protocol. HIV/HBV co-infection was 40.9%. The results showed that most (39.7%) study participants co-infected with HBV had a CD4 cell count of 350 cells/µl. The virological assay revealed that the highest HBsAg seroprevalence was detected in the study participants whose viral loads were between 40 and 1000µl (61.9%). The majority of the study participants were female HIV patients (74.5%), while those co-infected with HBV were mainly male patients (48.2%). HIV-positive individuals aged 18-30 (53.3%) were mostly affected. None of the socio-demographic variables tested was significantly associated with HBV in HIV-infected patients in Onitsha, Anambra State, Nigeria. This study showed a high HIV/HBV co-infection in Onitsha, Anambra State, Nigeria.

Evaluation of three hepatitis b virus detection protocols in blood donors

Hepatitis B virus (HBV) DNA diagnosis plays a critical role in the transmission of HBV infections. Accurate protocols in HBV detection will reduce the spread of the virus from blood donors. Therefore, this research compared the HBV detecting potentials of three different HBV protocols in the virus detection. Blood from 200 donors at the University college blood bank Ibadan were sampled and tested for HBV using the ABON™ HBsAg Hepatitis B Surface Antigen Tests (strip test), Monolisa TM HBsAg ULTRA (ELISA test) and Huruian biology HBV detection kit (qPCR test). HBV positive samples were genotyped by sequencing to ascertain genotype identity. Results showed that of the 200 samples tested, both ABON™ HBsAg Hepatitis B Surface Antigen Tests and Monolisa TM HBsAg ULTRA (for ELISA) did not record any positive sample. However, Huruian biology HBV detection kit via qPCR recorded a total of twenty-three positive samples. Of the twenty-three samples, twenty were of genotype E while three were of genotype B. The results from this study showed that that qPCR is more accurate in HBV virus detection than ELISA technique and also HBV genotype E is the most common genotype isolated in Nigeria.

Prevalence of HBsAg among patients attending a tertiary hospital in Port Harcourt, Nigeria

Nigeria has one of the greatest disease burdens from chronic viral hepatitis. Hepatitis B virus (HBV) infection is an important public health problem worldwide, more than two million people. Globally, around 96% of viral hepatitis deaths are attributable to HBV and Hepatitis C virus (HCV) but the prevalence of these infections is poorly characterized. Thus, this study aimed to investigate seroepidemiological aspects of HBV infection and its associated factors among patients attending a tertiary hospital in Port Harcourt, Nigeria. Serum samples from 92 participants were screened for a serological marker of HBV infection (HBsAg) by Monolisa HBsAg ULTRA enzyme-linked immunosorbent assay (ELISA) kit (manufactured by BIO RAD Laboratories, California, United States) following the manufacturer’s guidelines. Of the 92 patients tested, 10 (10.9%) were positive while 82 (89.1%) were negative. Among them (10/92), the majority were females (11.0%, 8/73) than males (10.5%, 2/19); the highest prevalence rate of an HBsAg occurred in the age group of 21-30 years (17.6%, 3/17). A higher prevalence of HBV (13.2%, 9/68) occurred in the married than singles (4.2%, 1/24). This study showed a high seroprevalence (10.9%), which indicates a rise in the prevalence of HBV in the study area. The findings of this study confirm the findings of other studies that HBV is endemic in Nigeria. These finding views females and males as fairly equivalent in the risk of HBV infection. As the prevalence of young adults were higher than older adults, this is considered cogent as younger adults are implicated as risk factors for HBV infection. This study adds important granularity to our understanding of the hepatitis epidemic. Large cross-sectional studies are needed to better characterize HBV prevalence, but mass screening may not be warranted.

Blood Safety: On-Site Verification Of The Screening Of HIV, HBV And HCV By Enzyme Linked Immuno-Sorbent Assay (ELISA) Kits From Bio-Rad Laboratories At The “Centre National De Transfusion Sanguine” (CNTS) Of Lomé In Togo

Background: Blood transfusion improves health and saves lives. Safe blood must be ensured for our populations. Quality assurance is a process that includes a set of coordinated activities in order to achieve the quality objective. Compliance with the quality management rules of medical biology laboratories requires verification of methods prior to their use. This study aimed to verify the on-site verification of the performance of the Enzyme Linked Immuno-Sorbent Assay (ELISA) method performed at the serology laboratory of the CNTS of Lomé. Methods: The performance of ELISA method performed at the serology laboratory of CNTS for the diagnosis of HIV, Hepatitis B and C with Bio-Rad Genscreen ULTRA-HIV Ag-Ac, Bio-Rad Monolisa-HBs Ag ULTRA and Bio-Rad Monolisa HCV Ag-Ac ULTRA V2 kits respectively was evaluated on repeatability, reproducibility, sensitivity and specificity according to COFRAC's SH GTA 04 reference. Results: The evaluation of the repeatability and reproducibility of each kit used in the laboratory resulted in compliant Coefficients of Variation (CV) with manufacturers’ ones. Sensitivities obtained with Bio-Rad Monolisa HCV Ag-Ac ULTRA V2, Bio-Rad Monolisa HBs Ag ULTRA and Bio-Rad Genscreen ULTRA HIV Ag-Ac kits were 94.59%, 98.08% and 100% respectively. For specificity tests, we found 86.49% with BIO-Rad Genscreen ULTRA-HIV Ag-Ac kit, 94.34% with Bio-Rad Monolisa HCV Ag-Ac ULTRA V2 kit and 97.37% with Bio-Rad Monolisa-HBs Ag ULTRA. Conclusion: In general, results were compliant except HIV diagnosis specificity. This study appears as a contribution to the establishment of a verification file for ELISA method used at the serology laboratory of CNTS of Lomé.

Seroprevalence and Factors Associated with Risk of Hepatitis B Virus Infection among Antenatal Attendees in ABUTH Zaria, Northwestern Nigeria.

Nigeria is one of the sub-Saharan African countries within the World Health Organization's (WHO) hyperendemic region for hepatitis B virus infection with prevalence greater than 8%. In this region, mother-to-child transmission is the major route of infection and approximately 90% of newborns of mothers who are seropositive for HBsAg and HBeAg become chronic carriers with a 25% risk of developing chronic liver diseases. This study aimed to determine the seroprevalence, and factors associated with risk of hepatitis B virus infection among antenatal attendees in Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. A hospital based cross sectional study was conducted among pregnant women Rattending the antenatal booking clinic of ABUTH, Zaria from August 2017 to January 2018. Systematic random sampling was used. An interviewer administered questionnaire was used to obtain data on sociodemographic characteristics and risk factors for HBV infection. Blood samples were collected and tested using the third generation ELISAkit for HBsAg (Monolisa HBsAg ULTRA BIORAD, France) and HBeAg(HBeAg & Ab, DiaPro Diagnostic Bioprobes Milano Italy). Data were analyzed using SPSS version 20 (IBM USA, 2011). Statistical testing was carried out with chi-squareand level of significance set as P<0.05. The mean age of the respondents was 26 ± 6.1 years, the highest HBV seropositivity occurred in the age group 21-25 years from a total of 192 participants. The seroprevalence of HBV obtained was 15.1%. Only1(3.4%) woman was positive for HBeAg among the 29 HBsAg seropositive women. Past history of unsafe injections was the only risk factor significantly associated with HBV seropositivity (x2= 5.628 p-value= 0.023). The seropositivity of hepatitis B virus was high among pregnant women. Interventions targeted at injection safety will help reduce the risk of infection.

Hepatitis B infection among HIV infected individuals in Gabon: Occult hepatitis B enhances HBV DNA prevalence.

In Gabon, a central African country, human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are endemic. In a recent study, conducted in a semi-urban area (Franceville, Gabon), HBV infection was found to be more prevalent among HIV infected individuals. This study aims to investigate the prevalence and genetic diversity of hepatitis B virus infection among HIV infected individuals, predominantly under antiretroviral therapy, living in fully urbanized area: Libreville, capital of Gabon. Serological and molecular tests were performed to detect HBV infection among patients living with HIV/AIDS (PLHA). We used Monolisa HBsAg ULTRA, Anti-HBc Plus and Anti-HBs Plus EIA kits for serological analyses. HBV DNA viral load (HBV DNA VL) was determined by real time PCR and molecular characterization of HBV strains was performed by sequencing and phylogenetic analysis of partial HBV surface and core genes. At all, 70.2% of patients were under antiretroviral therapy. The prevalence of HBsAg was 8.8% (43/487). Detectable HBV DNA was found in 69.7% (30/43) of HBsAg positive patients and in 17.5% (24/137) HBsAg negative patients. HBV DNA VL was significantly higher among patient with CD4 cell counts less than 200 cells/mm3 than those with CD4 cell counts greater than 500 cells/mm3 (p = 0.008). We confirmed the presence of HBV sub-genotypes QS-A3 (40%), and A4 (20%) and HBV-E genotype (40%). The percentage of resistance to Lamivudine was high (40%) and varied according to the M204V/I motif. Occult hepatitis B infection (OBI) was found in patients with isolated HBcAb and among patients who had completed their HBsAg seroconversion. We detected HBV DNA for one patient without any HBV serological marker. This study provides a new landmark for the comprehension of HBV infection in PLHA in urban areas. OBI enhances HBV DNA prevalence and should be investigated in all HBsAg negative individuals.

Prevalence, correlates and pattern of Hepatitis B among antenatal clinic attenders in Yaounde-Cameroon: is perinatal transmission of HBV neglected in Cameroon?

BackgroundFew studies have evaluated the prevalence of HBV in the general Cameroonian population or among antenatal attendants. The aim of this study was to determine the prevalence, correlates and patterns of Hepatitis B surface antigen among pregnant women attending antenatal care in Yaounde-Cameroon.MethodsThis was a cross-sectional multicenter study carried out in a referral hospital and two secondary hospitals in Yaounde, the capital of Cameroon. The study lasted 15 months (March 2011 to June 2012), and recruited 959 pregnant women. Patient recruitment was consecutive. The HBsAg was tested using the Monalisa HBsAg Ultra ELISA kit. Other hepatitis B markers were equally tested.We used the statistical package for social sciences (SPSS) version 14.0 software to conduct a quantitative analysis of the derived data. Simple descriptive statistics such as means, standard deviations, and proportions were used to describe the data. We tested for association in categorical variables using the chi-squared (χ2) test. The odds ratio (OR) and the corresponding 95% confidence intervals (95% CI) were used to summarise the strength of association between specific binary exposure and outcome variables. The level of statistical significance for the study was set at p < 0.05.ResultsThe prevalence of hepatitis B infection (HBsAg) among antenatal clinic attenders in our setting was 7.7%. Amongst these women, just 5.4% were previously aware of their HBsAg status. The rate of HBV infectivity was high, with 28% of HBsAg positive women having evidence of HBeAg in their plasma, and up to 45.8% of these women lacking antibodies against hepatitis B e antigen (anti-HBe). About 41% of the pregnant women had had previous contact with HBV as evidenced by the positive status for anti-HBc.Just 2.7% of the pregnant women had previously been vaccinated against HBV. The mean age for HBsAg positivity in our setting was 26.9 ±4.7 years, and the most affected age group was the 25 – 29 years age group. There was no statistically significant association between age or other socio-demographic risk factors and HBsAg status. Numerous risk factors for HBV acquisition exists in our settings, but amongst these, only a history of a contact with hepatitis B infection was found to be significantly associated with HBsAg positivity (OR 1.63, 95% C.I 1.15-2.30). Finally, the coinfection rate of HBV/HIV was 0.74%.ConclusionThe prevalence of hepatitis B among pregnant women in Cameroon is high, and the pattern tends towards high infectivity and therefore increased risk of perinatal HBV transmission. These highlight the need to step up preventive efforts against hepatitis B infection and perinatal HBV transmission in our community.

Nucleic acid testing for blood banks: An experience from a tertiary care centre in New Delhi, India

IntroductionBlood safety is a challenging task in India; with a population of around 1.23 billion and a high prevalence rate of HIV (0.29%), HBV (2–8%) and HCV (∼2%) in general population. Nucleic acid testing (NAT) in blood donor screening has been implemented in many developed countries to reduce the risk of transfusion-transmitted viral infections (TTIs). NAT shortens this window period, thereby offering blood centers a much higher sensitivity for detecting viral infections. Materials and methodsRoutine ID-NAT for HIV-1, HCV and HBV was started from June 2010 at AIIMS blood bank by the Procleix® Ultrio® Assay (Novartis Diagnostics, USA) a multiplex NAT, which allows the simultaneous detection of HIV-1, HCV, and HBV in a single tube. During the period of 27months from June 2010 to August 2012, around 73,898 samples were tested for all the three viruses using both ELISA (by Genscreen Ultra HIV Ag–Ab(BIO-RAD), Hepanostika HCV Ultra & HBsAg Ultra(Biomerieux) and Nucleic acid testing. The comparative results of both the assays are being presented here in this study. ResultsOut of 73,898 samples, 1104 samples (1.49%) were reactive by NAT. out of these 1104 samples, 73 were reactive for HIV-1 (0.09%), 186 were reactive for HCV only (0.25%), 779 (1.05%) were reactive for HBV only, and around 66 (0.08%) were HBV-HCV co-infections. There was one HIV, 37 HCV, 73 HBV and 10 HBV–HCV co-infection cases that were not detected by serology but reactive on NAT testing, with a combined yield of 1 in 610 donations (total 121 NAT yields). ConclusionNAT could detect HIV, HBV and HCV cases in blood donor samples that were undetected by serological tests. NAT can interdict a large number of infected unit transfusions and thus help in providing safe blood to the patients.

HIV infection and hepatitis B seroprevalence among antenatal clinic attendees in Niger, West Africa

This transversal study was suggested in order to estimate the nationwide seroprevalences of HIV infection and hepatitis B among 495 pregnant women in Niger in 2008. The study detected anti-HIV antibodies with Genscreen® Plus HIV Ag/Ab Ultra Kit (Bio-Rad; Hercules, CA), Vironostika® HIV Uni-Form II Ag/Ab (bioMérieux; Marcy-l’Etoile, France), and ImmunoComb® II HIV 1 and 2 BiSpot (Orgenics; Yavne, Israel). HBsAg was detected by Monolisa® HBsAg Ultra (Bio-Rad) and ImmunoComb® II HBsAg (Orgenics). The rates obtained were 2.02% (95% confidence intervals (CI): 1.03%–3.81%) and 16.16% (95% CI: 13.09%–19.77%), respectively. There were no significant variations according to environment, region, age, marital status, educational level, antecedent of surgery and transfusion. But these data need a large sample, and periodic updates for a better planning of activities in the framework of a national reproductive health program, including prevention of mother-to-child HIV transmission.

Hepatitis B virus transfusion risk in China: proficiency testing for the detection of hepatitis B surface antigen

Because of the high prevalence of Hepatitis B virus (HBV), HBsAg tests play an extremely significant role in donor screening in China. In our multicentre study, the HBsAg assays used in blood screening were evaluated for their analytical sensitivity and the ability to detect mutants. A panel of eight samples was sent to 85 blood banks. The panel included four HBsAg-positive serum samples at concentrations of 0·16, 0·46, 0·9 and 1·73 IU mL(-1) ; three recombinant HBsAg mutants (G145R, T131I and K141E) with defined concentrations and one negative sample. All laboratories were required to detect the samples with their routine procedures.All the 85 blood banks reported their results before the closing date, and 170 data sets were submitted. The wild-type samples at concentrations of 1·73 and 0·9 IU mL(-1) were correctly identified as positive in all data sets, whereas the other two samples (at concentrations 0·16 and 0·46 IU mL(-1) ) were not consistently detected as positive. Regarding the mutants, significantly different results were reported among all the assays involved. All users of Hepanostika HBsAg Ultra and most users (16/17) of Abbott Murex HBsAg Version 3 detected all mutant samples, whereas some of the commercial assays failed to detect any of the three mutant samples. Some HBsAg assays with unsatisfactory sensitivities and capabilities of mutant detection were used by a large percentage of blood banks, which might lead to a high transfusion risk in China. A list of assays of high sensitivity and good ability of mutant detection should be recommended for use in blood screening.

Occult Hepatitis B Virus Infection Among Blood Donors of North India

Background Hepatitis B virus (HBV) testing of blood donors in India is focused on the presence of HBsAg. However, the absence of HBsAg in the blood of the healthy individual may not be sufficient to ensure lack of circulating HBV. Aim The aim of this study is to estimate the prevalence of anti HBc and anti HBs pattern in anti HBc reactive but HBsAg negative blood donors. Material and Methods 6134 Blood donor samples were tested prospectively from 16th April to 7th July, 2007 for HbsAg and anti HBc (IgM + IgG) antibodies using BIORAD MONOLISA HbsAg ULTRA and BIO-RAD MONOLISA anti-HBc PLUS test kits. All the samples, which were negative for HbsAg but reactive for anti HBc, were tested for anti-HBs antibodies Using BIO-RAD MONOLISA ANTI HBs 3.0 test kits. Results Out of 6134 donor samples tested, 63 samples were HbsAg positive (1.02 %) and 499 samples (8.13%) showed anti HBc reactivity but HbsAg negative.195 (39.07%) out of 499 anti HBc positive samples showed levels of anti HBs above 15 IU/ml and 304 (60.92 %) showed levels of anti HBs below 15 IU/mL. The samples showing values above 15 IU/mL are considered positive and samples below 15 IU/mL are considered negative as per BIO-RAD MONOLISA anti HBs 3.0 instruction manual. Conclusion The data indicates that high percentage of blood donors (60.92%) were anti-HBc reactive and have low levels of preventive anti HBs antibodies. Accordingly all blood donor samples should be tested routinely for anti HBc and if the sera are reactive, regardless of anti-HBs titer, the blood should be discarded. Further testing for HBV-DNA is appropriate to follow up the blood donor for HBV infection.

HEALTH HAZARDS AMONG FIRE FIGHTERS

Background: Fire fighting is a physically demanding hazardous occupation. Fires are fought in a dynamic, changing, uncontrolled environment exposing workers to potentially toxic agents. The hazards of firefighting are classified as chemical, biological, physical, psychological and ergonomical. Objective: The aim of the present study was: (1) To investigate some of the health hazards among fire fighters with special emphasis on cytogenetic study and ventilatory functions. (2) To monitor the biological, psychological, reproductive and musculo-skeletal hazards. Subjects andmethodology: This study was conducted in a fire fighting station in El Omrania ElSharkia in Giza. The study was accomplished during the month of March 2007. The studied group comprised 24 workers in the fire fighting station. They were adult men aged between 18-33 years (23.20 ± 4.09), working on the basis of 12 hours/day with no day off. None of the workers used any protective equipment during working hours. They worked according to the need for help, and not all the time, bearing in mind that the worker may be exposed to frequent shifts or may be not exposed for several days.A referent group of 20 males matched for age [that ranged from 21-35 yrs., (23.40 ±4.05) ] , sex, socio-economic status and smoking habit , selected from relatives of the Kasr El Eini hospital patients, were also enrolled in our study. The following investigations were performed after taking individual consent: (A) All workers were interviewedusing a special questionnaire including occupational history; and full clinical examination was performed. (B) Ventilatory function tests were evaluated using aportable spirometer connected to a portable computer using the soft ware ZAN program,measuring FVC (Forced vital capacity), SVC (Slow vital capacity), FEV1%(Forced expiratory volume in the 1st second), FEV1/FVC %, PEF (Peak expiratoryflow) and (Mid expiratory flow 25-75%) MEF 25-75%. (C) Serological tests: a-HBV: Using enzyme linked immuo-sorbent assay (ELISA) HBsAg using BIORADMonolisa HBsAg ultra , Lot 7C0029 Monoclonal kit. b-HCV: Anti HCV using 3rdgeneration enzyme linked immuno sorbent-assay (ELISA) Innotest HCV Abs, Lot 165678. (D) Cytogenetic study Results: showed a statistically significant difference between the exposed and the control groups as regards spirometric evaluation. Ourresults revealed also a statistically significant difference between the exposed and the control groups as regards the chromosomal study, bearing in mind that the difference was in structural form not the numerical form. There was also a statistically significant difference between both groups as regards the occurrence of accidents, but there was no statistically significant difference between both groups as regards the psychological or reproductive hazards. Our research showed a statistically significant difference between the exposed and the control groups as regards HBV and HCV infections.Our results showed that there was a statistically significant correlation between the duration of exposure to toxins and hazardous agents in fire fighting and ventilatory function parameters. Our work illustrated that there was a statistically significant correlation between duration of exposure to toxins and hazardous agents in fire fighting and the appearance of gap and unbalanced re-arrangement in the romosomalstudy, but there was no statistically significant correlation as regards the rest of thechromosomal study. We emonstrated also that there was no statistically significantcorrelation between the age of the workers and the chromosomal aberrations. Recommendations:From the present study we recommend pre-employment and eriodicmedical examinations that should be performed to exclude those susceptible to lung diseases. Personal protective clothes and respiratory protective equipment should be used by fire fighters. Health education programs of workers about hazards of exposure to harmful agents and proper measures for protection is essential and this includestraining programs to raise awareness among fire fighters. Vaccination program should be applied to cover all the fire fighters specially against (HBV) . Rapid prophylactic treatment to injured workers and reporting system is mandatory. Finally follow recommended shift work pattern.

Evaluation of HBs Ag, HCV and HIV Ag-Ab Assays using Bio-Rad Elite Microplate Analyzer

In this study, we evaluated the performance of Elite microplate analyzer (Bio-Rad Laboratories, France) and the related assays (ULTRA line) for the detection of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Seroconversion panels, HBsAg positive/HBsAg negative (n=99/n=1,422), anti-HCV positive/negative (n=97/n=1,670), and anti-HIV positive/negative (n=112/n=1,704) samples were used to evaluate the performance of Monolisa HBsAg ULTRA, Monolisa HCV Ag-Ab ULTRA, and Genscreen ULTRA HIV Ag-Ab, respectively. The agreement of Elite microplate analyzer with CODA analyzer (Bio-Rad Laboratories, CA, USA) was also evaluated. The detection limit of Monolisa HBsAg ULTRA was 0.034 IU/mL. For Monolisa HBsAg ULTRA, Monolisa HCV Ag-Ab ULTRA, and Genscreen ULTRA HIV Ag-Ab, diagnostic sensitivities were all 100%, diagnostic specificities were 100%, 99.8% and 99.9%, and total CVs (coefficients of variation) were 13.8-17.5%, 3.4-5.2%, and 7.5-9.5%, respectively. The agreement of Elite microplate analyzer with CODA analyzer was 99.5%. The performance of Elite microplate analyzer and the related assays on analytical sensitivity, precision, early detection, diagnostic sensitivity and specificity was all adequate for a mass screening. However, further large multi-center studies should be performed to validate our results.

O.116 Reasons for the lack of anti-HBC antibody detection in hepatitis B virus chronically infected patients

Hepatitis B virus (HBV) testing of blood donors in India is focused on the presence of HBsAg. However, the absence of HBsAg in the blood of the healthy individual may not be sufficient to ensure lack of circulating HBV.The aim of this study is to estimate the prevalence of anti HBc and anti HBs pattern in anti HBc reactive but HBsAg negative blood donors.6134 Blood donor samples were tested prospectively from 16th April to 7th July, 2007 for HbsAg and anti HBc (IgM + IgG) antibodies using BIORAD MONOLISA HbsAg ULTRA and BIO-RAD MONOLISA anti-HBc PLUS test kits. All the samples, which were negative for HbsAg but reactive for anti HBc, were tested for anti-HBs antibodies Using BIO-RAD MONOLISA ANTI HBs 3.0 test kits.Out of 6134 donor samples tested, 63 samples were HbsAg positive (1.02 %) and 499 samples (8.13%) showed anti HBc reactivity but HbsAg negative.195 (39.07%) out of 499 anti HBc positive samples showed levels of anti HBs above 15 IU/ml and 304 (60.92 %) showed levels of anti HBs below 15 IU/mL. The samples showing values above 15 IU/mL are considered positive and samples below 15 IU/mL are considered negative as per BIO-RAD MONOLISA anti HBs 3.0 instruction manual.The data indicates that high percentage of blood donors (60.92%) were anti-HBc reactive and have low levels of preventive anti HBs antibodies. Accordingly all blood donor samples should be tested routinely for anti HBc and if the sera are reactive, regardless of anti-HBs titer, the blood should be discarded. Further testing for HBV-DNA is appropriate to follow up the blood donor for HBV infection.

A New HBsAg Screening Assay Designed for Sensitive Detection of HBsAg Subtypes and Variants

The design of a new HBsAg screening assay, the Hepanostika HBsAg Ultra is based on the use of monoclonal antibodies raised against native wild-type HBsAg and reactive with HBsAg in which the common ‘a’-determinant is modified by site-directed mutagenesis of four of the cysteine moieties. The design was checked using the same cysteine variants and samples from patients known to be infected with HBsAg variants. The results found were compared with other state-of-the-art commercial screening assays. The design of the Hepanostika HBsAg Ultra enabled detection of all variant HBsAg-positive samples in contrast to the other commercial assays. An additional 980 samples were tested to assess the specificity and sensitivity of the Hepanostika HBsAg Ultra. Screening of presumed negative serum and plasma samples resulted in a specificity of 100%. This makes the Hepanostika HBsAg Ultra the first screening assay with a design able to detect HBsAg variants with high sensitivity and specificity.