High throughput AS LNA qPCR method for the detection of a specific mutation in poliovirus vaccine strains

Sabin Inactivated Poliovirus Vaccine (sIPV) has become one of the preferred vaccination options for the last step in the Poliovirus eradication program. Sequencing of poliovirus samples is needed during the manufacturing of poliovirus vaccines to assure the safety and immunogenicity of these vaccines. Next-generation sequencing analysis is the current costly and time-consuming gold standard for monitoring the manufacturing processes. We developed a low-cost and quick, highly sensitive, and allele-specific locked nucleic acid-probe-based reverse transcription quantitative PCR alternative that can accurately detect mutations in poliovirus vaccine samples during process development, scaling up, and release. Using the frequently in vitro occurring and viral replication-impacting VP1-E295K mutation as a showcase, we show that this technology can accurately detect E295K mutations in poliovirus 2 samples to similar levels as NGS. The qPCR technology was developed employing a synthetic dsDNA fragment-based standard curve containing mixes of E295K-WT (wildtype) and Mut (mutant) synthetic dsDNA fragments ranging from 1 × 107 copies/µL to 1 × 102 copies/µL to achieve a linear correlation with R2 > 0.999, and PCR efficiencies of 95-105 %. Individual standard concentration levels achieved accuracies of ≥92 % (average 96 %) and precisions of ≤17 % (average 3.3 %) RSD. Specificity of locked nucleic acid (LNA)-probes was confirmed in the presence and absence of co-mutations in the probe-binding region. Application of the developed assay to Sabin Poliovirus type 2 production run samples, illustrated a linear relationship with an R2 of 0.994, and an average accuracy of 97.2 % of the variant (allele)-specific AS LNA qPCR result, compared to NGS. The assay showed good sensitivity for poliovirus samples, containing E295K mutation levels between 0 % and 95 % (quantification range). In conclusion, the developed AS LNA qPCR presents a valuable low-cost, and fast tool, suitable for the process development and quality control of polio vaccines.

Modeling the long-term 2-8 °C stability profiles of a live, rotavirus vaccine candidate (RV3-BB) in various liquid formulations via extrapolations of real-time and accelerated stability data

To accelerate the formulation development of live-virus vaccine (LVV) candidates, more rapid approaches to rank-order formulations and estimate their real-time storage stability losses are needed. In this case-study, we utilize new and previously described stability data of a live, rotavirus vaccine candidate (RV3-BB) in three different liquid formulations to model and compare predicted vs. experimental RV3-BB stability profiles. Linear-regression extrapolations of limited real-time (2-8 °C) stability data and Arrhenius modeling of accelerated (15, 25, 37 °C) stability data provided predictions of RV3-BB real-time stability profiles (2-8 °C, 24 months). Good correlations of modeled versus experimental stability data to rank-order the RV3-BB formulations were achieved by employing (1) a high-throughput RT-qPCR assay to measure viral titers, (2) additional assay replicates and stability time-points, and (3) a -80 °C control for each formulation to benchmark results at each stability time-point and temperature. Instead of accumulating two-year, 2-8 °C storage stability data, the same rank-ordering of the three RV3-BB formulations could have been achieved by modeling 37°, 25°, 15° (and 2-8 °C) stability data over 1, 3 and 12 months, respectively. The results of this case-study are discussed in the context of accelerating LVV formulation development by expeditiously identifying stable formulations, estimating their shelf-lives, and determining vaccine vial monitoring (VVM) designations.

HIV Epidemic in Libya: Identifying Gaps

BACKGROUND

HIV (human immunodeficiency virus) and AIDS (acquired immunodeficiency syndrome) became a public issue in Libya after the infection of 400 children in El-Fatih Hospital in 1988. Due to the civil war, social and religious barriers, HIV prevalence is hard to establish, but it is generally believed to be increasing.

OBJECTIVE

This review (a) assesses the size and scope of the available literature on the HIV epidemic in Libya; and, (b) identifies the nature and extent of research conducted to date.

METHODS

A comprehensive search was performed using PubMed, Medline, Web of Science, ScienceDirect, Scopus, Academic Search Ultimate, Cochrane Library and Google Scholar. Primary research studies and official reports that are exclusively on Libya published during 1988-2021 were considered.

RESULTS

In total 25 studies were included: Ten primary research studies, four online news articles, six Government reports, one letter to the editor, one manuscript, three online databases.

CONCLUSION

Despite the low-quality data, the literature suggests there is an increase in HIV infection rates in Libya. Culturally sensitive research on sexual activities, women, HIV preventative methods and attitudes of the Libyan public will assist in developing an effective National AIDS Programme, reducing HIV stigma, supporting People Living with HIV (PLHIV) and decreasing infection rates.

10 COVID-19 and Changing Perceptions Towards Postgraduate Surgical Training in United Kingdom

Aim

The evolution of the current coronavirus disease-2019 (COVID-19) pandemic continues to impact global healthcare systems on an unprecedented scale. Here, we use data from a local NHS trust within the United Kingdom (UK) to examine the perception of medical students and foundation doctors towards postgraduate surgical training.

Method

This tri-centric cross-sectional study was carried out via a survey disseminated within the East Sussex Healthcare NHS trust, King’s College Hospital, and King’s College London Medical School. The survey was active for 14 days (from 15th March 2020 to 28th March 2020), comprising a total of 40 foundation doctors and 10 medical students.

Results

A total of 50 responses were received across five hospitals and their associated medical school. A decrease of 10% and 25% was observed in interest to pursue surgery in medical students and foundation doctors, respectively, following the outbreak of COVID-19. Over 40% of foundation doctors holding postgraduate surgical training offers were not accepting them, and of those, over 40% would not consider reapplying to surgery. There was a drop in interest across a select set of specialities, and this was more obvious where aerosol-generating-procedures was a common occurrence.

Conclusions

These results highlight the need for a more efficient and effective response to address the immediate situation, as well as a robust contingency plan to avert the repercussions the surgical field could face.

Formulation development of a live attenuated human rotavirus (RV3-BB) vaccine candidate for use in low- and middle-income countries

Formulation development was performed with the live, attenuated, human neonatal rotavirus vaccine candidate (RV3-BB) with three main objectives to facilitate use in low- and middle- income countries including (1) a liquid, 2-8°C stable vaccine, (2) no necessity for pre-neutralization of gastric acid prior to oral administration of a small-volume dose, and (3) a low-cost vaccine dosage form. Implementation of a high-throughput RT-qPCR viral infectivity assay for RV3-BB, which correlated well with traditional FFA assays in terms of monitoring RV3-BB stability profiles, enabled more rapid and comprehensive formulation development studies. A wide variety of different classes and types of pharmaceutical excipients were screened for their ability to stabilize RV3-BB during exposure to elevated temperatures, freeze-thaw and agitation stresses. Sucrose (50-60% w/v), PEG-3350, and a solution pH of 7.8 were selected as promising stabilizers. Using a combination of an in vitro gastric digestion model (to mimic oral delivery conditions) and accelerated storage stability studies, several buffering agents (e.g., succinate, adipate and acetate at ~200 to 400 mM) were shown to protect RV3-BB under acidic conditions, and at the same time, minimize virus destabilization during storage. Several optimized RV3-BB candidate formulations were identified based on negligible viral infectivity losses during storage at 2-8°C and -20°C for up to 12 months, as well as by relative stability comparisons at 15°C and 25°C (up to 12 and 3 months, respectively). These RV3-BB stability results are discussed in the context of stability profiles of other rotavirus serotypes as well as future RV3-BB formulation development activities.

Developing a manufacturing process to deliver a cost effective and stable liquid human rotavirus vaccine

Despite solid evidence of the success of rotavirus vaccines in saving children from fatal gastroenteritis, more than 82 million infants worldwide still lack access to a rotavirus vaccine. The main barriers to global rotavirus vaccine coverage include cost, manufacturing capacity and suboptimal efficacy in low- and lower-middle income countries. One vaccine candidate with the potential to address the latter is based on the novel, naturally attenuated RV3 strain of rotavirus, RV3-BB vaccine administered in a birth dose strategy had a vaccine efficacy against severe rotavirus gastroenteritis of 94% at 12 months of age in infants in Indonesia. To further develop this vaccine candidate, a well-documented and low-cost manufacturing process is required. A target fully loaded cost of goods (COGs) of ≤$3.50 per course of three doses was set based on predicted market requirements. COGs modelling was leveraged to develop a process using Vero cells in cell factories reaching high titers, reducing or replacing expensive reagents and shortening process time to maximise output. Stable candidate liquid formulations were developed allowing two-year storage at 2-8 °C. In addition, the formulation potentially renders needless the pretreatment of vaccinees with antacid to ensure adequate gastric acid neutralization for routine oral vaccination. As a result, the formulation allows small volume dosing and reduction of supply chain costs. A dose ranging study is currently underway in Malawi that will inform the final clinical dose required. At a clinical dose of ≤6.3 log10 FFU, the COGs target of ≤$3.50 per three dose course was met. At a clinical dose of 6.5 log10 FFU, the final manufacturing process resulted in a COGs that is substantially lower than the current average market price, 2.44 USD per dose. The manufacturing and formulation processes were transferred to BioFarma in Indonesia to enable future RV3-BB vaccine production.

Effect of Formulation Variables on the Stability of a Live, Rotavirus (RV3-BB) Vaccine Candidate using in vitro Gastric Digestion Models to Mimic Oral Delivery

In this work, two different in vitro gastric digestion models were used to evaluate the stability of a live attenuated rotavirus vaccine candidate (RV3-BB) under conditions designed to mimic oral delivery in infants. First, a forced-degradation model was established at low pH to assess the buffering capacity of formulation excipients and to screen for RV3-BB stabilizers. Second, a sequential-addition model was implemented to examine RV3-BB stability under conditions more representative of oral administration to infants. RV3-BB rapidly inactivated at < pH 5.0 (37 °C, 1 h) as measured by an infectivity RT-qPCR assay. Pre-neutralization with varying volumes of infant formula (Enfamil®) or antacid (Mylanta®) conferred partial to full protection of RV3-BB. Excipients with sufficient buffering capacity to minimize acidic pH inactivation of RV3-BB were identified (e.g., succinate, acetate, adipate), however, they concomitantly destabilized RV3-BB in accelerated storage stability studies. Both effects were concentration dependent, thus excipient optimization was required to design candidate RV3-BB formulations which minimize acid-induced viral inactivation during oral delivery while not destabilizing the vaccine during long-term 2-8 °C storage. Finally, a statistical Design -of-Experiments (DOE) study examining RV3-BB stability in the in vitro sequential-addition model identified key formulation parameters likely affecting RV3-BB stability during in vivo oral delivery.

Clinical and bacteriological examinations of dogs with tonsillitis

The aim of this study was to investigate the presence of tonsillitis in dogs and isolation of bacteria involved as well as their antimicrobial susceptibility. For this purpose from June 2015 to August 2017, 12 clinical cases of dogs with tonsillitis have been examined, and a total of 24 samples were collected. Diagnosis was based on anamnesis, clinical signs, haematology and biochemical tests and bacteriological analyses. The isolation and identification of bacteria was carried out according to conventional microbiological methods and biochemical tests, while the antimicrobial susceptibility of bacterial isolates was tested using the disk diffusion method. Escherichia coli was the most commonly isolated bacteria with isolation rate 35.0%, followed by Streptococcus pyogenes (27.50%), Staphylococcus aureus (20%), Staphylococcus intermedius (10%) and Pasteurella spp. (7.5%). A high resistance to ampicillin, streptomicin and penicillin G was shown by E. coli, S. intermedius, S. pyogenes isolates. None of S. pyogenes, S. aureus, S. intermedius and Pasteurella spp., isolates was resistant to amoxicillin/clavulanic acid.

Process development of a New Haemophilus influenzae type b conjugate vaccine and the use of mathematical modeling to identify process optimization possibilities

Vaccination is one of the most successful public health interventions being a cost-effective tool in preventing deaths among young children. The earliest vaccines were developed following empirical methods, creating vaccines by trial and error. New process development tools, for example mathematical modeling, as well as new regulatory initiatives requiring better understanding of both the product and the process are being applied to well-characterized biopharmaceuticals (for example recombinant proteins). The vaccine industry is still running behind in comparison to these industries. A production process for a new Haemophilus influenzae type b (Hib) conjugate vaccine, including related quality control (QC) tests, was developed and transferred to a number of emerging vaccine manufacturers. This contributed to a sustainable global supply of affordable Hib conjugate vaccines, as illustrated by the market launch of the first Hib vaccine based on this technology in 2007 and concomitant price reduction of Hib vaccines. This paper describes the development approach followed for this Hib conjugate vaccine as well as the mathematical modeling tool applied recently in order to indicate options for further improvements of the initial Hib process. The strategy followed during the process development of this Hib conjugate vaccine was a targeted and integrated approach based on prior knowledge and experience with similar products using multi-disciplinary expertise. Mathematical modeling was used to develop a predictive model for the initial Hib process (the 'baseline' model) as well as an 'optimized' model, by proposing a number of process changes which could lead to further reduction in price. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:568-580, 2016.

Vitamin D status and insulin sensitivity are novel predictors of resting metabolic rate: a cross-sectional analysis in Australian adults

PURPOSE

Resting metabolic rate (RMR) accounts for two-thirds of the total energy expenditure in sedentary individuals. After accounting for traditional factors, there still remains a considerable unexplained variance in RMR. There is a pandemic of obesity and metabolic syndrome (MetS) which coexists with a high prevalence of vitamin D insufficiency. The aim of this study was to evaluate the potential effects of vitamin D status, insulin sensitivity (IS) and the metabolic syndrome (MetS) on RMR in Australian adults.

METHODS

RMR, respiratory quotient (RQ), McAuley's insulin sensitivity index, fat mass (FM), fat-free mass (FFM) and vitamin D status were assessed in Australian adults. The presence of MetS was evaluated by current standard criteria. Predictors of RMR were examined through multiple linear regression based on stepwise and backward regression approaches with attention to multi-collinearity. All analyses were conducted on SPSS version 21.

RESULTS

One hundred and twenty-seven participants (45 men, 82 women), aged 53.4 ± 11.7 years and BMI 31.9 ± 5.2 kg/m(2), were included. Forty-one subjects were insufficient in vitamin D status (<50 nmol/L), and 75 participants had the MetS. A parsimonious regression model explained 85.8 % of RMR and was given by: RMR (kJ/d) = 1931 + 83.5 × FFM (kg) + 29.5 × FM (kg) + 5.65 × 25(OH)D (nmol/L) - 17.6 × age (years) - 57.51 × IS.

CONCLUSION

Vitamin D status and IS are novel independent predictors of RMR in adults. Future studies could validate a causal role for these factors in human energy metabolism.

Isolation and Identification of Brucella melitensis Biovar 3 from Vaccinated Small Ruminants: A Public Health Threat in Kosovo

In 2011, a human brucellosis case with severe clinical symptoms was reported at the University Clinic for Infectious Diseases in Prishtina, Kosovo. A trace-back investigation was conducted to find the source of human infection. A total of 49 blood samples and 15 corresponding milk samples from sheep and goats raised on the patient's farm were taken for serological and molecular analysis. Serology using RBT and CFT revealed 11 positive animals. Twelve milk samples were PCR positive. A Brucella strain isolated from a goat's milk sample was classified as Brucella melitensis biovar 3, indicating the first ever isolation and report in Kosovo. The use of the Bruce-ladder PCR provided differentiation between the field strain and the vaccine strain. Hence, the accidental transmission of the vaccine strain Rev 1 that was previously used for the vaccination of the farm animals could be excluded. The findings of this study show that brucellosis is still a public health threat in Kosovo despite control measures.

Use of immuno assays during the development of a Hemophilus influenzae type b vaccine for technology transfer to emerging vaccine manufacturers

Quality control of Hemophilus Influenzae type b (Hib) conjugate vaccines is mainly dependent on physicochemical methods. Overcoming sample matrix interference when using physicochemical tests is very challenging, these tests are therefore only used to test purified samples of polysaccharide, protein, bulk conjugate, and final product. For successful development of a Hib conjugate vaccine, several ELISA (enzyme-linked immunosorbent assay) methods were needed as an additional tool to enable testing of in process (IP) samples. In this paper, three of the ELISA's that have been very valuable during the process development, implementation and scaling up are highlighted. The PRP-ELISA, was a very efficient tool in testing in process (IP) samples generated during the development of the cultivation and purification process of the Hib-polysaccharide. The antigenicity ELISA, was used to confirm the covalent linkage of PRP and TTd in the conjugate. The anti-PRP IgG ELISA was developed as part of the immunogenicity test, used to demonstrate the ability of the Hib conjugate vaccine to elicit a T-cell dependent immune response in mice. ELISA methods are relatively cheap and easy to implement and therefore very useful during the development of polysaccharide conjugate vaccines.

Preclinical evaluation of a Haemophilus influenzae type b conjugate vaccine process intended for technology transfer

Introduction of Haemophilus influenzae type b (Hib) vaccine in low- and middle-income countries has been limited by cost and availability of Hib conjugate vaccines for a long time. It was previously recognized by the Institute for Translational Vaccinology (Intravacc, originating from the former Vaccinology Unit of the National Institute of Public Health [RIVM] and the Netherlands Vaccine Institute [NVI]) that local production of a Hib conjugate vaccine would increase the affordability and sustainability of the vaccine and thereby help to speed up Hib introduction in these countries. A new affordable and a non-infringing production process for a Hib conjugate vaccine was developed, including relevant quality control tests, and the technology was transferred to a number of vaccine manufacturers in India, Indonesia, and China. As part of the Hib technology transfer project managed by Intravacc, a preclinical toxicity study was conducted in the Netherlands to test the safety and immunogenicity of this new Hib conjugate vaccine. The data generated by this study were used by the technology transfer partners to accelerate the clinical development of the new Hib conjugate vaccine. A repeated dose toxicity and local tolerance study in rats was performed to assess the reactogenicity and immunogenicity of a new Hib conjugate vaccine compared to a licensed vaccine. The results showed that the vaccine was well tolerated and immunogenic in rats, no major differences in both safety and immunogenicity in rats were found between the vaccine produced according to the production process developed by Intravacc and the licensed one. Rats may be useful to verify the immunogenicity of Hib conjugate vaccines and for preclinical evaluation. In general, nonclinical evaluation of the new Hib conjugate vaccine, including this proof of concept (safety and immunogenicity study in rats), made it possible for technology transfer partners, having implemented the original process with no changes in the manufacturing process and vaccine formulation, to start directly with phase 1 clinical trials.

Quantification of water as a potential risk factor for cross-contamination with Salmonella, Campylobacter and Listeria in a poultry abattoir

Water used in a modern poultry processing line was tested from October 2005 to June 2006 to determine the level of bacteria in an abattoir in Germany. A total of 420 water samples were taken from 14 processing sites (PSs), at 10 times, and from three different hours of the working shift at three sampling hours (SHs) at 5:00 a.m. (SH 1), 9:00 a.m. (SH 2) and 12:00 a.m. (SH 3). Each sample was assessed for the aerobic plate count (APC) and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia over 30 sampling weeks. The APC numbers of each PS from three SHs were compared, and the prevalence of Salmonella, Campylobacter, Listeria and Yersinia from each PS of three SHs was determined as well as change from the initial PS to the end of the processing line. A total of 46 water samples were positive for Salmonella, 120 positive for Campylobacter and 4 positive for Listeria. None of the water samples was found to be positive for Yersinia. During the course of the day, the APC increased. Salmonella was mostly found during SH 1 (5 a.m.) in water from all PSs. A high number of Campylobacter were observed at SH 2 (9 a.m.) and SH 3 (12 a.m.) from all PSs. The results show that water, which is still used in substantial amounts in present poultry processing technology, can serve as a carrier for Salmonella and Campylobacter. The findings indicate that birds might progressively contaminate the equipment and become contaminated via the same equipment, that water at every processing position of the line constitutes a risk and that more attention should be paid to effective water management in the processing plan.

Vaccinology capacity building in Europe for innovative platforms serving emerging markets

The 2012 Terrapinn World Vaccine Congress held from 16 to 18 October in Lyon addressed in a dedicated session the transfer of innovative vaccine technologies from Europe to emerging markets. Past and recent transfers and experiences from Europe's public domain were summarized by the Netherlands' National Institute for Public Health and the Environment (RIVM) in Bilthoven. The role of capacity building through training courses for developing country partners was highlighted in several recent technology transfer programs developed in collaboration with the World Health Organisation (WHO). In another stream of the Congress, a case of human vaccine technology transfer from Europe's private sector to an emerging economy recipient in India was presented. The continuing globalization of vaccinology is further illustrated by the recent acquisition in 2012 of the Netherlands' public vaccine manufacturing capacity in Bilthoven by the Serum Institute of India Ltd, an emerging vaccine manufacturer. In a parallel development, the Netherlands' government decided to transform RIVM's vaccinology research and development capacity into a new not-for-profit entity: "the Institute for Translational Vaccinology" (see citation 1 in Note section for web address). Under a public private partnership structure, InTraVacc's mission will include the fostering of global health through international partnerships in innovative vaccinology. Projected activities will include training courses and curricula, capitalizing on various currently established platform technologies and the legacy of previous "producer -producer" collaborations between the RIVM and emerging manufacturers over the past 40 y. It is suggested to consider this as a basis for a common initiative from Europe to develop and implement a practical vaccinology course for emerging countries with particular focus to the African region.

Influence of methods for Trichinella detection in pigs from endemic and non-endemic European region

A total of 1401 German and 226 Croatian pigs raised either indoors or outdoors were tested for Trichinella infection by direct and indirect detection methods. A 10 g sample of diaphragm were examined for muscle larvae by the artificial digestion method; the species was determined by multiplex polymerase chain reaction (PCR). For detection of anti-Trichinella IgG, serum samples diluted 1:100, and meat juice samples diluted 1:10, were tested by enzyme-linked immunosorbent assay. All German pigs and those Croatian pigs raised indoors proved to be Trichinella-negative by all methods. Muscle larvae were detected in a total of eleven of the Croatian pigs, which were raised on small outdoor farms. For eight isolates, PCR results demonstrated that recovered larvae were Trichinella spiralis. Anti-Trichinella-IgG was detected in serum and meat juice of digestion positive animals when the worm burdens exceeded 0.38 larvae per gram of muscle. Positive results in Croatian pigs indicate a higher risk of infection for outdoor farming in areas where Trichinella is endemic. Results of direct and indirect detection were compared and are discussed with special regard to specificity and sensitivity of methods.