Collaboration within the global vaccine safety surveillance ecosystem during the COVID-19 pandemic: lessons learnt and key recommendations from the COVAX Vaccine Safety Working Group

This analysis describes the successes, challenges and opportunities to improve global vaccine safety surveillance as observed by the Vaccine Safety Working Group from its role as a platform of exchange for stakeholders responsible for monitoring the safety of vaccines distributed through the COVAX mechanism. Three key elements considered to be essential for ongoing and future pandemic preparedness for vaccine developers in their interaction with other members of the vaccine safety ecosystem are (1) the availability of infrastructure and capacity for active vaccine safety surveillance in low-income and middle-income countries (LMICs), including the advancement of concepts of safety surveillance and risk management to vaccine developers and manufacturers from LMICs; (2) more comprehensive mechanisms to ensure timely exchange of vaccine safety data and/or knowledge gaps between public health authorities and vaccine developers and manufacturers; and (3) further implementation of the concept of regulatory reliance in pharmacovigilance. These aims would both conserve valuable resources and allow for more equitable access to vaccine safety information and for benefit/risk decision-making.

Benefit-risk assessment of vaccines

Benefit-risk assessment (BRA) is critical for decision-making throughout the vaccine life cycle. It requires scientific assessment of evidence to make an informed judgment on whether the vaccine has a favourable benefit-risk profile i.e. the benefits of the vaccine outweigh its risks for use in its intended indication. The assessment must also consider data gaps and uncertainties, using sensitivity analyses to show the impact of these uncertainties in the assessment. The BRA field has advanced considerably over the past years, including the use of structured BRA frameworks, quantitative BRA models and use of the patient experience data. Analytical tools and procedures to standardize BRA implementation have become increasingly important. A Benefit-Risk Assessment Module has been prepared to enable the planning, assessment, and communication of relevant BRA information via a structured B-R framework. The module can help facilitate the conduct and communication of defensible BRAs by vaccine developers, funders, regulators and policy makers in high, middle or low-income countries, both for regulatory submissions and in public health responses to infectious diseases, including for epidemics.

The Brighton collaboration standardized module for vaccine benefit-risk assessment

Vaccine Benefit-Risk (B-R) assessment consists of evaluating the benefits and risks of a vaccine and making a judgment whether the expected key benefits outweigh the potential key risks associated with its expected use. B-R supports regulatory and public health decision-making throughout the vaccine's lifecycle. In August 2021, the Brighton Collaboration's Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Benefit-Risk Assessment Module working group was established to develop a standard module to support the planning, conduct and evaluation of structured B-R assessments for vaccines from different platforms, based on data from clinical trials, post-marketing studies and real-world evidence. It enables sharing of relevant information via value trees, effects tables and graphical depictions of B-R trade-offs. It is intended to support vaccine developers, funders, regulators and policy makers in high-, middle- or low-income countries to help inform decision-making and facilitate transparent communication concerning development, licensure, deployment and other lifecycle decisions.

Lessons learned from COVID-19, H1N1, and routine vaccine pharmacovigilance in the United States: a path to a more robust vaccine safety program

INTRODUCTION

Vaccine pharmacovigilance is an essential component of vaccine safety programs. Vaccine pharmacovigilance refers to detecting uncommon adverse events following immunization (AEFI), determining whether they are due to the vaccine or are only a coincidence, and, for those AEFI considered related to vaccination, characterizing them further. When AEFI are due to vaccination, it is important to characterize the attributable risk and ascertain the biological mechanism causing the adverse reaction to inform efforts to prevent or mitigate the risk. A robust post-authorization safety system is necessary for vaccine decision-making, clinical recommendations, vaccine compensation, and vaccine communication and confidence.

AREAS COVERED

This paper describes the key characteristics of vaccine pharmacovigilance programs, reviews US vaccine pharmacovigilance for routine vaccination programs, COVID-19, and H1N1, and makes recommendations for improving future vaccine safety systems.

EXPERT OPINION

The key characteristics of vaccine pharmacovigilance programs include passive surveillance, active surveillance, clinical investigation and special studies, and causality assessment. Recent examples illustrate the strengths of US pharmacovigilance systems, including systems for passive and active surveillance, as well as areas for improvement, including study of pathogenesis, consistent funding, and leadership. We make recommendations that would, if implemented, further strengthen the vaccine safety system for future routine and pandemic immunizations.

System and facility readiness assessment for conducting active surveillance of adverse events following immunization in Addis Ababa, Ethiopia

BACKGROUND

To help distinguish vaccine-related adverse events following immunization (AEFI) from coincidental occurrences, active vaccine pharmacovigilance (VP) prospective surveillance programs are needed. From February to May 2021, we assessed the system and facility readiness for implementing active AEFI VP surveillance in Addis Ababa, Ethiopia.

METHODS

Selected hospitals were assessed using a readiness assessment tool with scoring measures. The site assessment was conducted via in-person interviews within the specific departments in each hospital. We evaluated the system readiness with a desk review of AEFI guidelines, Expanded Program for Immunization Guidelines and Ethiopian Food and Drug Administration and Ethiopian Public Health Institute websites.

RESULTS

Of the hospitals in Addis Ababa, 23.1% met the criteria for our site assessment. During the system readiness assessment, we found that essential components were in place. However, rules, regulations and proclamations pertaining to AEFI surveillance were absent. Based on the tool, the three hospitals (A, B and C) scored 60.6% (94/155), 48.3% (75/155) and 40% (62/155), respectively.

CONCLUSIONS

Only one of three hospitals assessed in our evaluation scored >50% for readiness to implement active AEFI surveillance. We also identified the following areas for improvement to ensure successful implementation: training, making guidelines and reporting forms available and ensuring a system that accommodates paper-based and electronic-based recording systems.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Novavax COVID-19 Vaccine (NVX-CoV2373), a recombinant spike protein vaccine with Matrix-M adjuvant to prevent disease caused by SARS-CoV-2 viruses

Novavax, a global vaccine company, began evaluating NVX-CoV2373 in human studies in May 2020 and the pivotal placebo-controlled phase 3 studies started in November 2020; five clinical studies provided adult and adolescent clinical data for over 31,000 participants who were administered NVX-CoV2373. This extensive data has demonstrated a well-tolerated response to NVX-CoV2373 and high vaccine efficacy against mild, moderate, or severe COVID-19 using a two-dose series (Dunkle et al., 2022) [1], (Heath et al., 2021) [2], (Keech et al., 2020) [3], (Mallory et al., 2022) [4]. The most common adverse events seen after administration with NVX-CoV2373 were injection site tenderness, injection site pain, fatigue, myalgia, headache, malaise, arthralgia, nausea, or vomiting. In addition, immunogenicity against variants of interest (VOI) and variants of concern (VOC) was established with high titers of ACE2 receptor-inhibiting and neutralizing antibodies in these studies (EMA, 2022) [5], (FDA, 2023) [6]. Further studies on correlates of protection determined that titers of anti-Spike IgG and neutralizing antibodies correlated with efficacy against symptomatic COVID-19 established in clinical trials (p < 0.001 for recombinant protein vaccine and p = 0.005 for mRNA vaccines for IgG levels) (Fong et al., 2022) [7]. Administration of a booster dose of the recombinant protein vaccine approximately 6 months following the primary two-dose series resulted in substantial increases in humoral antibodies against both the prototype strain and all evaluated variants, similar to or higher than the antibody levels observed in phase 3 studies that were associated with high vaccine efficacy (Dunkle et al., 2022) [1], (Mallory et al., 2022) [4]. These findings, together with the well tolerated safety profile, support use of the recombinant protein vaccine as primary series and booster regimens.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Medigen COVID-19 protein vaccine

The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Working Group has prepared standardized templates to describe the key considerations for the benefit-risk assessment of several vaccine platform technologies, including protein subunit vaccines. This article uses the BRAVATO template to review the features of the MVC-COV1901 vaccine, a recombinant protein subunit vaccine based on the stabilized pre-fusion SARS-CoV-2 spike protein S-2P, adjuvanted with CpG 1018 and aluminum hydroxide, manufactured by Medigen Vaccine Biologics Corporation in Taiwan. MVC-COV1901 vaccine is indicated for active immunization to prevent COVID-19 caused by SARS-CoV-2 in individuals 12 years of age and older. The template offers details on basic vaccine information, target pathogen and population, characteristics of antigen and adjuvant, preclinical data, human safety and efficacy data, and overall benefit-risk assessment. The clinical development program began in September 2020 and based on demonstration of favorable safety and immunogenicity profiles in 11 clinical trials in over 5,000 participants, it has been approved for emergency use based on immunobridging results for adults in Taiwan, Estwatini, Somaliland, and Paraguay. The main clinical trials include placebo-controlled phase 2 studies in healthy adults (CT-COV-21), adolescents (CT-COV-22), and elderly population (CT-COV-23) as well as 3 immunobridging phase 3 trials (CT-COV-31, CT-COV-32, and CT-COV-34) in which MVC-COV1901 was compared to AZD1222. There are also clinical trials studying MVC-COV1901 as homologous and heterologous boosters (CT-COV-24 and CT-COV-25). The totality of evidence based on ∼3 million vaccinees to date includes a mostly clean safety profile, with adverse events mostly being mild and self-limiting in both clinical development and post-marketing experience, proven immunogenic response, and real-world effectiveness data. The immunogenic profile demonstrates that MVC-COV1901 induces high levels of neutralizing and binding antibodies against SARS-CoV-2. There is a dose-dependent response and a significant correlation between binding and neutralizing antibody activity. Antigen-specific T-cell responses, particularly a Th1-biased immune response characterized by high levels of interferon gamma and IL-2 cytokines, have also been observed. Coupled with this, MVC-COV1901 has favorable thermostability and better safety profiles when compared to other authorized vaccines from different platforms, which make it potentially a good candidate for vaccine supply chains in global markets.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for the Moderna COVID-19 Vaccine (mRNA-1273)

The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) Working Group has prepared standardized templates to describe the key considerations for the benefit-risk assessment of several vaccine platform technologies, including nucleic acid (RNA and DNA) vaccines. This paper uses the BRAVATO template to review the features of a vaccine employing a proprietary mRNA vaccine platform to develop Moderna COVID-19 Vaccine (mRNA-1273); a highly effective vaccine to prevent coronavirus disease 2019 (Covid-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In response to the pandemic the first in human studies began in March 2020 and the pivotal, placebo-controlled phase 3 efficacy study in over 30,000 adults began in July 2020. Based on demonstration of efficacy and safety at the time of interim analysis in November 2020 and at the time of trial unblinding in March 2021, the mRNA-1273 received Emergency Use Authorization in December 2020 and full FDA approval in January 2022.

Vaccines based on the replication-deficient simian adenoviral vector ChAdOx1: Standardized template with key considerations for a risk/benefit assessment

Replication-deficient adenoviral vectors have been under investigation as a platform technology for vaccine development for several years and have recently been successfully deployed as an effective COVID-19 counter measure. A replication-deficient adenoviral vector based on the simian adenovirus type Y25 and named ChAdOx1 has been evaluated in several clinical trials since 2012. The Brighton Collaboration Benefit-Risk Assessment of VAccines by TechnolOgy (BRAVATO) was formed to evaluate the safety and other key features of new platform technology vaccines. This manuscript reviews key features of the ChAdOx1-vectored vaccines. The simian adenovirus Y25 was chosen as a strategy to circumvent pre-existing immunity to common human adenovirus serotypes which could impair immune responses induced by adenoviral vectored vaccines. Deletion of the E1 gene renders the ChAdOx1 vector replication incompetent and further genetic engineering of the E3 and E4 genes allows for increased insertional capability and optimizes vaccine manufacturing processes. ChAdOx1 vectored vaccines can be manufactured in E1 complementing cell lines at scale and are thermostable. The first ChAdOx1 vectored vaccines approved for human use, against SARS-CoV-2, received emergency use authorization in the UK on 30th December 2020, and is now approved in more than 180 countries. Safety data were compiled from phase I-III clinical trials of ChAdOx1 vectored vaccines expressing different antigens (influenza, tuberculosis, malaria, meningococcal B, prostate cancer, MERS-CoV, Chikungunya, Zika and SARS-CoV-2), conducted by the University of Oxford, as well as post marketing surveillance data for the COVID-19 Oxford-AstraZeneca vaccine. Overall, ChAdOx1 vectored vaccines have been well tolerated. Very rarely, thrombosis with thrombocytopenia syndrome (TTS), capillary leak syndrome (CLS), immune thrombocytopenia (ITP), and Guillain-Barre syndrome (GBS) have been reported following mass administration of the COVID-19 Oxford-AstraZeneca vaccine. The benefits of this COVID-19 vaccination have outweighed the risks of serious adverse events in most settings, especially with mitigation of risks when possible. Extensive immunogenicity clinical evaluation of ChAdOx1 vectored vaccines reveal strong, durable humoral and cellular immune responses to date; studies to refine the COVID-19 protection (e.g., via homologous/heterologous booster, fractional dose) are also underway. New prophylactic and therapeutic vaccines based on the ChAdOx1 vector are currently undergoing pre-clinical and clinical assessment, including vaccines against viral hemorrhagic fevers, Nipah virus, HIV, Hepatitis B, amongst others.

Advancing the Science of Vaccine Safety During the Coronavirus Disease 2019 (COVID-19) Pandemic and Beyond: Launching an International Network of Special Immunization Services

Within 2 years after the start of the coronavirus disease 2019 (COVID-19) pandemic, novel severe acute respiratory syndrome coronavirus 2 vaccines were developed, rigorously evaluated in large phase 3 trials, and administered to more than 5 billion individuals globally. However, adverse events of special interest (AESIs) have been described post-implementation, including myocarditis after receipt of messenger RNA (mRNA) vaccines and thrombosis with thrombocytopenia syndrome after receipt of adenoviral vector vaccines. AESIs are rare (<1 to 10/100 000 vaccinees) and less frequent than COVID-19 complications, though they have associated morbidity and mortality. The diversity of COVID-19 vaccine platforms (eg, mRNA, viral vector, protein) and rates of AESIs both between and within platforms (eg, higher rate of myocarditis after mRNA-1273 vs BNT162b2 vaccines) present an important opportunity to advance vaccine safety science. The International Network of Special Immunization Services has been formed with experts in vaccine safety, systems biology, and other relevant disciplines to study cases of AESIs and matched controls to uncover the pathogenesis of rare AESIs and inform vaccine development.

A Brighton Collaboration standardized template with key considerations for a benefit/risk assessment for a soluble glycoprotein vaccine to prevent disease caused by Nipah or Hendra viruses

Auro Vaccines LLC has developed a protein vaccine to prevent disease from Nipah and Hendra virus infection that employs a recombinant soluble Hendra glycoprotein (HeV-sG) adjuvanted with aluminum phosphate. This vaccine is currently under clinical evaluation in a Phase 1 study. The Benefit-Risk Assessment of VAccines by TechnolOgy Working Group (BRAVATO; ex-V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of protein vaccines. This will help key stakeholders to assess potential safety issues and understand the benefit-risk of such a vaccine platform. The structured and standardized assessment provided by the template may also help contribute to improved public acceptance and communication of licensed protein vaccines.

Evolving pharmacovigilance requirements with novel vaccines and vaccine components

This paper explores the pipeline of new and upcoming vaccines as it relates to monitoring their safety. Compared with most currently available vaccines, that are constituted of live attenuated organisms or inactive products, future vaccines will also be based on new technologies. Several products that include such technologies are either already licensed or at an advanced stage of clinical development. Those include viral vectors, genetically attenuated live organisms, nucleic acid vaccines, novel adjuvants, increased number of antigens present in a single vaccine, novel mode of vaccine administration and thermostabilisation. The Global Advisory Committee on Vaccine Safety (GACVS) monitors novel vaccines, from the time they become available for large scale use. GACVS maintains their safety profile as evidence emerges from post-licensure surveillance and observational studies. Vaccines and vaccine formulations produced with novel technologies will have different safety profiles that will require adapting pharmacovigilance approaches. For example, GACVS now considers viral vector templates developed on the model proposed by Brighton Collaboration. The characteristics of those novel products will also have implications for the risk management plans (RMPs). Questions related to the duration of active monitoring for genetic material, presence of adventitious agents more easily detected with enhanced biological screening, or physiological mechanisms of novel adjuvants are all considerations that will belong to the preparation of RMPs. In addition to assessing those novel products and advising experts, GACVS will also consider how to more broadly communicate about risk assessment, so vaccine users can also benefit from the committee’s advice.

Suitability of databases in the Asia-Pacific for collaborative monitoring of vaccine safety

INTRODUCTION

Information regarding availability of electronic healthcare databases in the Asia-Pacific region is critical for planning vaccine safety assessments particularly, as COVID-19 vaccines are introduced. This study aimed to identify data sources in the region, potentially suitable for vaccine safety surveillance. This manuscript is endorsed by the International Society for Pharmacoepidemiology (ISPE).

METHODS

Nineteen countries targeted for database reporting were identified using published country lists and review articles. Surveillance capacity was assessed using two surveys: a 9-item introductory survey and a 51-item full survey. Survey questions related to database characteristics, covariate and health outcome variables, vaccine exposure characteristics, access and governance, and dataset linkage capability. Other questions collated research/regulatory applications of the data and local publications detailing database use for research.

RESULTS

Eleven databases containing vaccine-specific information were identified across 8 countries. Databases were largely national in coverage (8/11, 73%), encompassed all ages (9/11, 82%) with population size from 1.4 to 52 million persons. Vaccine exposure information varied particularly for standardized vaccine codes (5/11, 46%), brand (7/11, 64%) and manufacturer (5/11, 46%). Outcome data were integrated with vaccine data in 6 (55%) databases and available via linkage in 5 (46%) databases. Data approval processes varied, impacting on timeliness of data access.

CONCLUSIONS

Variation in vaccine data availability, complexities in data access including, governance and data release approval procedures, together with requirement for data linkage for outcome information, all contribute to the challenges in building a distributed network for vaccine safety assessment in the Asia-Pacific and globally. Common data models (CDMs) may help expedite vaccine safety research across the region.

The critical role of background rates of possible adverse events in the assessment of COVID-19 vaccine safety

Beginning in December of 2019, a novel coronavirus, SARS-CoV-2, emerged in China and is now a global pandemic with extensive morbidity and mortality. With the emergence of this threat, an unprecedented effort to develop vaccines against this virus began. As vaccines are now being introduced globally, we face the prospect of millions of people being vaccinated with multiple types of vaccines many of which use new vaccine platforms. Since medical events happen without vaccines, it will be important to know at what rate events occur in the background so that when adverse events are identified one has a frame of reference with which to compare the rates of these events so as to make an initial assessment as to whether there is a potential safety concern or not. Background rates vary over time, by geography, by sex, socioeconomic status and by age group. Here we describe two key steps for post-introduction safety evaluation of COVID-19 vaccines: Defining a dynamic list of Adverse Events of Special Interest (AESI) and establishing background rates for these AESI. We use multiple examples to illustrate use of rates and caveats for their use. In addition we discuss tools available from the Brighton Collaboration that facilitate case evaluation and understanding of AESI.

Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) standardized template for collection of key information for benefit-risk assessment of live-attenuated viral vaccines

Several live-attenuated viral vaccine candidates are among the COVID-19 vaccines in development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of live-attenuated viral vaccines. This will help key stakeholders assess potential safety issues and understand the benefit-risk of such vaccines. The standardized and structured assessment provided by the template would also help to contribute to improved communication and support public acceptance of licensed live-attenuated viral vaccines.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of inactivated viral vaccines

Inactivated viral vaccines have long been used in humans for diseases of global health threat and are now among the vaccines for COVID-19 under development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of inactivated viral vaccines. This will help key stakeholders to assess potential safety issues and understand the benefit-risk of the vaccine platform. The standardized and structured assessment provided by the template would also help to contribute to improved communication and support public acceptance of licensed inactivated viral vaccines.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of protein vaccines

Several protein vaccine candidates are among the COVID-19 vaccines in development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of protein vaccines. This will help key stakeholders to assess potential safety issues and understand the benefit-risk of such a vaccine platform. The structured and standardized assessment provided by the template would also help contribute to improved public acceptance and communication of licensed protein vaccines.

The Brighton Collaboration standardized template for collection of key information for benefit-risk assessment of nucleic acid (RNA and DNA) vaccines

Nucleic acid (DNA and RNA) vaccines are among the most advanced vaccines for COVID-19 under development. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) has prepared a standardized template to describe the key considerations for the benefit-risk assessment of nucleic acid vaccines. This will facilitate the assessment by key stakeholders of potential safety issues and understanding of overall benefit-risk. The structured assessment provided by the template can also help improve communication and public acceptance of licensed nucleic acid vaccines.

Consensus summary report for CEPI/BC March 12-13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines

A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.

Defining the interval for monitoring potential adverse events following immunization (AEFIs) after receipt of live viral vectored vaccines

Live viral vectors that express heterologous antigens of the target pathogen are being investigated in the development of novel vaccines against serious infectious agents like HIV and Ebola. As some live recombinant vectored vaccines may be replication-competent, a key challenge is defining the length of time for monitoring potential adverse events following immunization (AEFI) in clinical trials and epidemiologic studies. This time period must be chosen with care and based on considerations of pre-clinical and clinical trials data, biological plausibility and practical feasibility. The available options include: (1) adapting from the current relevant regulatory guidelines; (2) convening a panel of experts to review the evidence from a systematic literature search to narrow down a list of likely potential or known AEFI and establish the optimal risk window(s); and (3) conducting "near real-time" prospective monitoring for unknown clustering's of AEFI in validated large linked vaccine safety databases using Rapid Cycle Analysis for pre-specified adverse events of special interest (AESI) and Treescan to identify previously unsuspected outcomes. The risk window established by any of these options could be used along with (4) establishing a registry of clinically validated pre-specified AESI to include in case-control studies. Depending on the infrastructure, human resources and databases available in different countries, the appropriate option or combination of options can be determined by regulatory agencies and investigators.

Effect of point-of-care CD4 cell count results on linkage to care and antiretroviral initiation during a home-based HIV testing campaign: a non-blinded, cluster-randomised trial

BACKGROUND

HIV disease staging with referral laboratory-based CD4 cell count testing is a key barrier to the initiation of antiretroviral treatment (ART). Point-of-care CD4 cell counts can improve linkage to HIV care among people living with HIV, but its effect has not been assessed with a randomised controlled trial in the context of home-based HIV counselling and testing (HBCT).

METHODS

We did a two-arm, cluster-randomised, controlled efficacy trial in two districts of western Kenya with ongoing HBCT. Housing compounds were randomly assigned (1:1) to point-of-care CD4 cell counts (366 compounds with 417 participants) or standard-of-care (318 compounds with 353 participants) CD4 cell counts done at one of three referral laboratories serving the study catchment area. In each compound, we enrolled people with HIV not engaged in care in the previous 6 months. All participants received post-test counselling and referral for HIV care. Point-of-care test participants received additional counselling on the result, including ART eligibility if CD4 was less than 350 cells per μL, the cutoff in Kenyan guidelines. Participants were interviewed 6 months after enrolment to ascertain whether they sought HIV care, verified through chart reviews at 23 local clinics. The prevalence of loss to follow-up at 6 months (LTFU) was listed as the main outcome in the study protocol. We analysed linkage to care at 6 months (defined as 1-LTFU) as the primary outcome. All analyses were by intention to treat. This trial is registered at ClinicalTrials.gov, number NCT02515149.

FINDINGS

We enrolled 770 participants between July 1, 2013, and Feb 28, 2014. 692 (90%) had verified linkage to care status and 78 (10%) were lost to follow-up. Of 371 participants in the point-of-care group, 215 (58%) had linked to care within 6 months versus 108 (34%) of 321 in the standard-of-care group (Cox proportional multivariable hazard ratio [HR] 2·14, 95% CI 1·67-2·74; log rank p<0·0001).

INTERPRETATION

Point-of-care CD4 cell counts in a resource-limited HBCT setting doubled linkage to care and thereby improved ART initiation. Given the substantial economic and logistic hindrances to providing ART for all people with HIV in resource-limited settings in the near term, point of care CD4 cell counts might have a role in prioritising care and improving linkage to care.

FUNDING

US Centers for Disease Control and Prevention.

Laboratory-based performance evaluation of PIMA CD4+ T-lymphocyte count point-of-care by lay-counselors in Kenya

BACKGROUND

CD4+ T-lymphocyte count testing at the point-of-care (POC) may improve linkage to care of persons diagnosed with HIV-1 infection, but the accuracy of POC devices when operated by lay-counselors in the era of task-shifting is unknown. We examined the accuracy of Alere's Pima™ POC device on both capillary and venous blood when performed by lay-counselors and laboratory technicians.

METHODS

In Phase I, we compared the perfomance of POC against FACSCalibur™ for 280 venous specimens by laboratory technicians. In Phase II we compared POC performance by lay-counselors versus laboratory technicians using 147 paired capillary and venous specimens, and compared these to FACSCalibur™. Statistical analyses included Bland-Altman analyses, concordance correlation coefficient, sensitivity, and specificity at treatment eligibility thresholds of 200, 350, and 500cells/μl.

RESULTS

Phase I: POC sensitivity and specificity were 93.0% and 84.1% at 500cells/μl, respectively. Phase II: Good agreement was observed for venous POC results from both lay-counselors (concordance correlation coefficient (CCC)=0.873, bias -86.4cells/μl) and laboratory technicians (CCC=0.920, bias -65.7cells/μl). Capillary POC had good correlation: lay-counselors (CCC=0.902, bias -71.2cells/μl), laboratory technicians (CCC=0.918, bias -63.0cells/μl). Misclassification at the 500 cells/μl threshold for venous blood was 13.6% and 10.2% for lay-counselors and laboratory technicians and 12.2% for capillary blood in both groups. POC tended to under-classify the CD4 values with increasingly negative bias at higher CD4 values.

CONCLUSIONS

Pima™ results were comparable to FACSCalibur™ for both venous and capillary specimens when operated by lay-counselors. POC CD4 testing has the potential to improve linkage to HIV care without burdening laboratory technicians in resource-limited settings.

Adventitious agents and live viral vectored vaccines: Considerations for archiving samples of biological materials for retrospective analysis

Vaccines are one of the most effective public health medicinal products with an excellent safety record. As vaccines are produced using biological materials, there is a need to safeguard against potential contamination with adventitious agents. Adventitious agents could be inadvertently introduced into a vaccine through starting materials used for production. Therefore, extensive testing has been recommended at specific stages of vaccine manufacture to demonstrate the absence of adventitious agents. Additionally, the incorporation of viral clearance steps in the manufacturing process can aid in reducing the risk of adventitious agent contamination. However, for live viral vaccines, aside from possible purification of the virus or vector, extensive adventitious agent clearance may not be feasible. In the event that an adventitious agent is detected in a vaccine, it is important to determine its origin, evaluate its potential for human infection and pathology, and discern which batches of vaccine may have been affected in order to take risk mitigation action. To achieve this, it is necessary to have archived samples of the vaccine and ancillary components, ideally from developmental through to current batches, as well as samples of the biological materials used in the manufacture of the vaccine, since these are the most likely sources of an adventitious agent. The need for formal guidance on such vaccine sample archiving has been recognized but not fulfilled. We summarize in this paper several prior major cases of vaccine contamination with adventitious agents and provide points for consideration on sample archiving of live recombinant viral vector vaccines for use in humans.

Live virus vaccines based on a vesicular stomatitis virus (VSV) backbone: Standardized template with key considerations for a risk/benefit assessment

The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viral and other microbial pathogens in their genome (so-called "chimeric virus vaccines"). Many such viral vector vaccines are now at various stages of clinical evaluation. Here, we introduce an attenuated form of recombinant vesicular stomatitis virus (rVSV) as a potential chimeric virus vaccine for HIV-1, with implications for use as a vaccine vector for other pathogens. The rVSV/HIV-1 vaccine vector was attenuated by combining two major genome modifications. These modifications acted synergistically to greatly enhance vector attenuation and the resulting rVSV vector demonstrated safety in sensitive mouse and non-human primate neurovirulence models. This vector expressing HIV-1 gag protein has completed evaluation in two Phase I clinical trials. In one trial the rVSV/HIV-1 vector was administered in a homologous two-dose regimen, and in a second trial with pDNA in a heterologous prime boost regimen. No serious adverse events were reported nor was vector detected in blood, urine or saliva post vaccination in either trial. Gag specific immune responses were induced in both trials with highest frequency T cell responses detected in the prime boost regimen. The rVSV/HIV-1 vector also demonstrated safety in an ongoing Phase I trial in HIV-1 positive participants. Additionally, clinical trial material has been produced with the rVSV vector expressing HIV-1 env, and Phase I clinical evaluation will initiate in the beginning of 2016. In this paper, we use a standardized template describing key characteristics of the novel rVSV vaccine vectors, in comparison to wild type VSV. The template facilitates scientific discourse among key stakeholders by increasing transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines.

Vaccination and unexplained sudden death risk in Taiwanese infants

PURPOSE

In March 1992, eight infants who had died within 36 hours of receiving whole-cell pertussis vaccine (diphtheria, tetanus, and whole-cell pertussis [DTwP]) prompted the Taiwan health authorities to suspend its use. We conducted an investigation of vaccination and sudden unexplained infant death (SUID) and repeated it more recently after Taiwan switched to acellular pertussis vaccine (diphtheria, tetanus, and acellular pertussis [DTaP]) in 2010.

METHODS

All SUIDs aged 31-364 days during 1990-1992 and 1996-2013 were selected from the death registration databases. The case-control investigation matched each case to two controls on clinic, sex, and birth date, whereas the follow-up self-controlled case series study compared risk of death during the 30-day post-vaccination risk periods with those in the control periods within the same case.

RESULTS

Sudden unexplained infant death was associated with never receiving DTwP (odds ratio 2.28, 95% confidence interval 1.25-4.15) in the case-control investigation. The odds ratios within 0-1, 2-7, 8-14, and 15-30 days of DTwP administration were 1.18, 0.26, 0.50, and 0.77. In the 1996-2013 self-controlled case series studies, this temporal shift between DTwP and SUID was consistently observed for female (incidence rate ratio 1.70, 0.75, 1.01, and 0.84) but not male or DTaP recipients. A pooled analysis showed significant risk within 2 days of receiving DTwP in female infants (incidence rate ratio 1.66, 95% confidence interval 1.05-2.60).

CONCLUSIONS

Being unvaccinated and recent receipt of DTwP in female infants was significantly associated with SUID; the latter was consistent with a temporal shift pattern without overall increase in risk. The currently used pertussis vaccine, DTaP, did not increase risk of SUID. Copyright © 2016 John Wiley & Sons, Ltd.

Contributions and challenges for worldwide vaccine safety: The Global Advisory Committee on Vaccine Safety at 15 years

In 1999, the Global Advisory Committee on Vaccine Safety (GACVS) was established by the World Health Organization (WHO) to provide independent scientific advice on issues relating to the safety of vaccines and immunization. Fifteen years onward, we conducted a multi-faceted review to evaluate the impact, reach and challenges facing GACVS, including the role GACVS plays in informing global, regional and WHO member state vaccine policy. The methods included measures of organizational structure, citation impact, themes approached, and a discussion by previous and current members to evaluate past, present and future challenges. Given the increasing range of data sources and the deployment of many new vaccines, the Committee is facing the complex task of identifying the best available evidence for recommendations on vaccine safety. To help meet the increased demand for public transparency in decision making, GACVS-structured methodology for evidence-based decisions is evolving. GACVS also promotes best practices and capacity building for timely and accurate risk assessment; risk communications; outreach to help countries maintain and, if needed, rebuild public trust in vaccines; and advocacy for bridging the major gaps in vaccine safety capacity globally.

Enhancing Vaccine Safety Capacity Globally: A Lifecycle Perspective

Major vaccine safety controversies have arisen in several countries beginning in the last decades of 20th century. Such periodic vaccine safety controversies are unlikely to go away in the near future as more national immunization programs mature with near elimination of target vaccine-preventable diseases that result in relative greater prominence of adverse events following immunizations, both true reactions and temporally coincidental events. There are several ways in which vaccine safety capacity can be improved to potentially mitigate the impact of future vaccine safety controversies. This paper aims to take a "lifecycle" approach, examining some potential pre- and post-licensure opportunities to improve vaccine safety, in both developed (specifically U.S. and Europe) and low- and middle-income countries.

Enhancing vaccine safety capacity globally: A lifecycle perspective

Major vaccine safety controversies have arisen in several countries beginning in the last decades of 20th century. Such periodic vaccine safety controversies are unlikely to go away in the near future as more national immunization programs mature with near elimination of target vaccine-preventable diseases that result in relative greater prominence of adverse events following immunizations, both true reactions and temporally coincidental events. There are several ways in which vaccine safety capacity can be improved to potentially mitigate the impact of future vaccine safety controversies. This paper aims to take a "lifecycle" approach, examining some potential pre- and post-licensure opportunities to improve vaccine safety, in both developed (specifically U.S. and Europe) and low- and middle-income countries.

Live virus vaccines based on a yellow fever vaccine backbone: standardized template with key considerations for a risk/benefit assessment

The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to evaluate the safety of live, recombinant viral vaccines incorporating genes from heterologous viruses inserted into the backbone of another virus (so-called "chimeric virus vaccines"). Many viral vector vaccines are in advanced clinical trials. The first such vaccine to be approved for marketing (to date in Australia, Thailand, Malaysia, and the Philippines) is a vaccine against the flavivirus, Japanese encephalitis (JE), which employs a licensed vaccine (yellow fever 17D) as a vector. In this vaccine, two envelope proteins (prM-E) of YF 17D virus were exchanged for the corresponding genes of JE virus, with additional attenuating mutations incorporated into the JE gene inserts. Similar vaccines have been constructed by inserting prM-E genes of dengue and West Nile into YF 17D virus and are in late stage clinical studies. The dengue vaccine is, however, more complex in that it requires a mixture of four live vectors each expressing one of the four dengue serotypes. This vaccine has been evaluated in multiple clinical trials. No significant safety concerns have been found. The Phase 3 trials met their endpoints in terms of overall reduction of confirmed dengue fever, and, most importantly a significant reduction in severe dengue and hospitalization due to dengue. However, based on results that have been published so far, efficacy in preventing serotype 2 infection is less than that for the other three serotypes. In the development of these chimeric vaccines, an important series of comparative studies of safety and efficacy were made using the parental YF 17D vaccine virus as a benchmark. In this paper, we use a standardized template describing the key characteristics of the novel flavivirus vaccine vectors, in comparison to the parental YF 17D vaccine. The template facilitates scientific discourse among key stakeholders by increasing the transparency and comparability of information. The Brighton Collaboration V3SWG template may also be useful as a guide to the evaluation of other recombinant viral vector vaccines.

Correlates of prevalent HIV infection among adults and adolescents in the Kisumu incidence cohort study, Kisumu, Kenya

We estimated HIV prevalence and identified correlates of HIV infection among 1106 men and women aged 16-34 years residing in Kisumu, Kenya. Demographic, sexual, and other behavioural data were collected using audio computer-assisted self-interview in conjunction with a medical examination, real-time parallel rapid HIV testing, and laboratory testing for pregnancy, gonorrhoea, chlamydia, syphilis, and herpes simplex virus type 2. Multivariate logistic regression was used to identify variables associated with prevalent HIV infection by gender. Overall HIV prevalence was 12.1%. HIV prevalence among women (17.1%) was approximately two-and-one-half times the prevalence among men (6.6%). Odds of HIV infection in men increased with age (aOR associated with one-year increase in age = 1.21, CI = 1.07-1.35) and were greater among those who were uncircumcised (aOR = 4.42, CI = 1.41-13.89) and those who had an herpes simplex virus type 2-positive (aOR = 3.13, CI = 1.12-8.73) test result. Odds of prevalent HIV infection among women also increased with age (aOR associated with one-year increase in age = 1.16, CI = 1.04-1.29). Women who tested herpes simplex virus type 2 positive had more than three times the odds (aOR = 3.85, CI = 1.38-10.46) of prevalent HIV infection compared with those who tested herpes simplex virus type 2 negative. Tailored sexual health interventions and programs may help mitigate HIV age and gender disparities.

The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG)

Recombinant viral vectors provide an effective means for heterologous antigen expression in vivo and thus represent promising platforms for developing novel vaccines against human pathogens from Ebola to tuberculosis. An increasing number of candidate viral vector vaccines are entering human clinical trials. The Brighton Collaboration Viral Vector Vaccines Safety Working Group (V3SWG) was formed to improve our ability to anticipate potential safety issues and meaningfully assess or interpret safety data, thereby facilitating greater public acceptance when licensed.

Rates of adverse events associated with male circumcision in U.S. medical settings, 2001 to 2010

IMPORTANCE

Approximately 1.4 million male circumcisions (MCs) are performed annually in US medical settings. However, population-based estimates of MC-associated adverse events (AEs) are lacking.

OBJECTIVES

To estimate the incidence rate of MC-associated AEs and to assess whether AE rates differed by age at circumcision.

DESIGN

We selected 41 possible MC AEs based on a literature review and on medical billing codes. We estimated a likely risk window for the incidence calculation for each MC AE based on pathogenesis. We used 2001 to 2010 data from SDI Health, a large administrative claims data set, to conduct a retrospective cohort study.

SETTING AND PARTICIPANTS

SDI Health provided administrative claims data from inpatient and outpatient US medical settings.

MAIN OUTCOMES AND MEASURES

For each AE, we calculated the incidence per million MCs. We compared the incidence risk ratio and the incidence rate difference for circumcised vs uncircumcised newborn males and for males circumcised at younger than 1 year, age 1 to 9 years, or 10 years or older. An AE was considered probably related to MC if the incidence risk ratio significantly exceeded 1 at P < .05 or occurred only in circumcised males.

RESULTS

Records were available for 1,400,920 circumcised males, 93.3% as newborns. Of 41 possible MC AEs, 16 (39.0%) were probable. The incidence of total MC AEs was slightly less than 0.5%. Rates of potentially serious MC AEs ranged from 0.76 (95% CI, 0.10-5.43) per million MCs for stricture of male genital organs to 703.23 (95% CI, 659.22-750.18) per million MCs for repair of incomplete circumcision. Compared with boys circumcised at younger than 1 year, the incidences of probable AEs were approximately 20-fold and 10-fold greater for males circumcised at age 1 to 9 years and at 10 years or older, respectively.

CONCLUSIONS AND RELEVANCE

Male circumcision had a low incidence of AEs overall, especially if the procedure was performed during the first year of life, but rose 10-fold to 20-fold when performed after infancy.

Medical risks and benefits of newborn male circumcision in the United States: physician perspectives

INTRODUCTION

In 2012, the American Academy of Pediatrics (AAP) and the American Congress of Obstetricians and Gynecologists (ACOG) published recommendations that physicians should discuss with parents the benefits and risks of newborn male circumcision. Our objective was to assess physicians' perspectives of newborn male circumcision.

METHODS

A self-administered, cross-sectional electronic survey of US physicians was conducted in 2008 (N = 1500).

RESULTS

Approximately one-third (33.2%) of the respondents reported that their current perspective was that the medical benefits outweigh the risks associated with newborn male circumcision and less than one-third (31.1%) reported they would recommend the procedure when counseling parents.

CONCLUSIONS

In 2008, only about one-third of the physicians surveyed thought that the benefits of male circumcision outweighed the risks and recommended it to parents of newborn sons. These attitudes may be relevant to the declining circumcision rates in the United States. Repeat surveys may be useful, given the new AAP and ACOG recommendations.

Evaluation of syndromic management of sexually transmitted infections within the Kisumu Incidence Cohort Study

While laboratory aetiological diagnosis is considered the gold standard for diagnosis and management of sexually transmitted infections (STIs), syndromic management has been presented as a simplified and affordable approach for STI management in limited resource settings. STI signs and symptoms were collected using staff-administered computer-assisted personal interview and audio computer-assisted self-interview. Participants underwent a medical examination and laboratory testing for common STIs. The performance of syndromic management was assessed on the agreement between interviewing methods as well as accurate diagnosis. We screened 846 participants, of whom 88 (10.4%) received syndromic STI diagnosis while 272 (32.2%) received an aetiological diagnosis. Agreement between syndromic and aetiological diagnoses was very poor (overall kappa = 0.09). The most prevalent STI was herpes simplex virus type 2 and the percentage of persons with any STI was higher among women (48.6%) than men (15.6%, p < 0.0001). Agreement between audio computer-assisted self-interview and computer-assisted personal interview interviewing methods for syndromic diagnosis of STIs ranged from poor to good. Our findings suggest that syndromic management of STIs is not a sufficient tool for STI diagnosis in this setting; development and improvement of STI diagnostic capabilities through laboratory confirmation is needed in resource-limited settings.

Men who have sex with men in Kisumu, Kenya: comfort in accessing health services and willingness to participate in HIV prevention studies

Men who have sex with men (MSM) are a crucial and marginalized at risk population for HIV in Africa but are poorly studied. Like other areas of Africa, homosexuality is illegal in Kenya. We assessed MSM comfort in accessing health services and willingness to participate in HIV prevention research in Kisumu, Kenya-an area of high HIV prevalence. We conducted a two-phase formative study with individual interviews (n = 15) and a structured survey (n = 51). Peer contact or snowball method (n = 43, 84.3%) was the primary recruitment strategy used to locate MSM. Exact logistic regression models were used for survey data analysis. Over 60% (32/51) of survey participants were not very comfortable seeking health services from a public hospital. Almost all MSM (49/51; 96.1%) reported willingness to be contacted to participate in future HIV research studies. Efforts to provide facilities that offer safe and confidential health services and health education for MSM is required. Continued community engagement with the MSM population in Kenya is needed to guide best practices for involving them in HIV prevention research.

Investigation of HIV Incidence Rates in a High-Risk, High-Prevalence Kenyan Population: Potential Lessons for Intervention Trials and Programmatic Strategies

Cost-effective HIV prevention programs should target persons at high risk of HIV acquisition. We conducted an observational HIV incidence cohort study in Kisumu, Kenya, where HIV prevalence is triple that of the national rate. We used referral and venue-sampling approaches to enroll HIV-negative persons for a 12-month observational cohort, August 2010 to September 2011, collected data using computer-assisted interviews, and performed HIV testing quarterly. Among 1292 eligible persons, 648 (50%) were excluded for HIV positivity and other reasons. Of the 644 enrollees, 52% were women who were significantly older than men (P<.01). In all, 7 persons seroconverted (incidence rate [IR] per 100 person-years=1.11; 95% confidence interval [CI] 0.45-2.30), 6 were women; 5 (IR=3.14; 95% CI 1.02-7.34) of whom were ≤25 years. Most new infections occurred in young women, an observation consistent with other findings in sub-Saharan Africa that women aged ≤25 years are an important population for HIV intervention trials in Africa.

Template protocol for clinical trials investigating vaccines--focus on safety elements

This document is intended as a guide to the protocol development for trials of prophylactic vaccines. The template may serve phases I-IV clinical trials protocol development to include safety relevant information as required by the regulatory authorities and as deemed useful by the investigators. This document may also be helpful for future site strengthening efforts.

Correlates of health attitudes among homosexual and bisexual men

There is increased emphasis on physician attention to the overall health and wellness of homosexual and bisexual men, though little is known about the health-related attitudes of these groups. This study determined factors associated with the health attitudes of homosexual and bisexual men and identified preferred sources of health information. For this study, the 2008 ConsumerStyles panel survey was used to create three health attitude scales and to determine factors associated with each scale. The three scales were labeled: (1) health motivation; (2) relationship with health care provider; and (3) self-perception of health literacy. In addition to other factors, higher scores for health motivation and relationship with health care provider were associated with black compared with white men. In contrast, lower scores for self-perception of health literacy were associated with black compared with white men. For information on an unfamiliar health condition, most homosexual and bisexual men chose the Internet. Black homosexual and bisexual men reported being motivated to be healthy and working well with their health care provider to manage their health. However, their perception of their own health motivation was low compared with the white men. Attempts to improve health literacy through Internet sites may be helpful in improving health attitudes and reducing negative health outcomes.

Baseline findings of an HIV incidence cohort study to prepare for future HIV prevention clinical trials in Kisumu, Kenya

Introduction

In an analysis of baseline findings of an HIV incidence cohort study, an assessment was made of HIV prevalence among persons presenting for enrollment and any differences in demographic characteristics between persons not enrolled compared to those enrolled. We also described and compared HIV risk behaviors in males and females enrolled in the study.

Methodology

A computer-assisted survey was administered to collect baseline demographic and HIV risk data from 1,277 men and women aged 18–34 years. Testing for HIV and other sexually transmitted infections (STI) was conducted. Out of 1,277 persons prescreened for eligibility, 625 were enrolled.

Results

HIV prevalence of all persons who completed screening was 14.8% (females: 21.1%; males: 8.1%). The odds of being enrolled in the study were higher for persons 18–24 years compared to those 30–34 years of age [adjusted odds ratio (AOR)=2.18, CI=1.13, 4.21] and males compared to females [AOR=2.07, CI=1.43, 2.99]. Among those enrolled in the study, the most prevalent HIV risk behaviors were unprotected sex (49%), alcohol use (45%), and transactional sex (30%) in the last three months. Compared to females, a significantly greater proportion of males reported using any alcohol or recreational drug in the last three months, a history of oral sex, sex with partner other than a spouse or main partner, ever having a blood transfusion, ever being treated for an STI, and having knowledge of their last HIV test result.

Conclusion

The Kisumu Field Station successfully recruited individuals with HIV risk characteristics for the HIV incidence cohort study.

Investigation of an outbreak of hypersensitivity-type reactions during the 2004 national measles-mumps-rubella vaccination campaign in Brazil

INTRODUCTION

During Brazil's national measles, mumps, and rubella (MMR) vaccination campaign in August 2004, an unexpectedly high rate of hypersensitivity-type adverse events (HAEs) was reported.

MATERIALS AND METHODS

We reviewed information about children with suspected HAEs reported by clinicians to Brazil's national passive surveillance system for adverse events following immunization (AEFI), compared attack rate of HAE by manufacturer of MMR vaccine used in the campaign, and conducted a case-control study to determine possible risk factors for HAEs.

RESULTS

During the 2004 national campaign, the rate of HAEs following MMR vaccination was one log higher for manufacturer A (15.2/100,000 doses administered) compared to the other two manufacturers (1.2 and 0.6/100,000 doses; p<0.0001); a similar pattern was observed retrospectively in analysis of the 2000-2003 AEFI surveillance (0.95 vs. 0.07 per 100,000 doses administered; p<0.0001). In the case-control study, among the 49 case-patients with HAEs identified, reported symptoms included conjunctival injection (60%), urticaria (55%), fever (54%), and facial edema (53%); no deaths occurred. The median time interval between vaccination and symptom onset was 42min (range: 5min-24h). We did not identify any differences in the proportion of case-patients and control children with a history of known allergy to food (including egg, egg-containing products or gelatin), drugs, or environmental antigens.

DISCUSSION

Our study highlights the importance of a well-functioning routine AEFI surveillance system linked with mass vaccination campaigns. Such a system in Brazil permitted timely detection of HAEs and validation of a safety signal associated with one vaccine manufacturer. Unlike earlier publications, this outbreak linked to a single manufacturer of MMR showed no association with a prior allergic history to eggs or other foods, including gelatin; subsequent studies implicate the dextran stabilizer in MMR from manufacturer A as the likely cause of HAEs.

Need for physician education on the benefits and risks of male circumcision in the United States

Physicians may be called upon to counsel male patients or parents of newborn males regarding their decision to circumcise their newborn sons. The purpose of the present study was to describe physicians who do not understand the benefits and risks associated with male circumcision well enough to counsel parents of newborn male infants and adult men. A self-administered, cross-sectional electronic survey of physicians was conducted in 2008. We analyzed responses from 1,500 physicians (510 family practitioners, 490 internists, 250 pediatricians, and 250 obstetricians/gynecologists). Nearly 22% (n = 327/1500) reported they did not understand the risks and benefits of newborn male circumcision well enough to counsel parents and 40.3% (n = 504/1250) reported not understanding the risks and benefits well enough to counsel adult men. A substantial minority of physicians may need additional training and/or information about current male circumcision research to feel comfortable counseling parents of newborn male infants or adult men.

Ultracompact and fabrication-tolerant integrated polarization splitter

Design and fabrication of a 2×2 two-mode interference (TMI) coupler based on-chip polarization splitter is presented. By changing the angle between the access waveguides, one can tune the effective TMI length for the mode with less optical confinement (transverse magnetic, TM) to coincide with the target TMI length for a desired transmission of the mode with higher optical confinement (transverse electric, TE). The fabricated 0.94 μm long 2×2 TMI splits the input power into TM (bar) and TE (cross) outputs with splitting ratio over 15 dB over 50 nm bandwidth. Fabrication tolerance analysis shows that the device is tolerant to fabrication errors as large as 60 nm.