Smallpox death in Britain challenges presumption of laboratory safety

Vaccinia Virus: From Crude Smallpox Vaccines to Elaborate Viral Vector Vaccine Design

Various vaccinia virus (VACV) strains were applied during the smallpox vaccination campaign to eradicate the variola virus worldwide. After the eradication of smallpox, VACV gained popularity as a viral vector thanks to increasing innovations in genetic engineering and vaccine technology. Some VACV strains have been extensively used to develop vaccine candidates against various diseases. Modified vaccinia virus Ankara (MVA) is a VACV vaccine strain that offers several advantages for the development of recombinant vaccine candidates. In addition to various host-restriction genes, MVA lacks several immunomodulatory genes of which some have proven to be quite efficient in skewing the immune response in an unfavorable way to control infection in the host. Studies to manipulate these genes aim to optimize the immunogenicity and safety of MVA-based viral vector vaccine candidates. Here we summarize the history and further work with VACV as a vaccine and present in detail the genetic manipulations within the MVA genome to improve its immunogenicity and safety as a viral vector vaccine.

Clinical Laboratory Biosafety Gaps: Lessons Learned from Past Outbreaks Reveal a Path to a Safer Future

Patient care and public health require timely, reliable laboratory testing. However, clinical laboratory professionals rarely know whether patient specimens contain infectious agents, making ensuring biosafety while performing testing procedures challenging. The importance of biosafety in clinical laboratories was highlighted during the 2014 Ebola outbreak, where concerns about biosafety resulted in delayed diagnoses and contributed to patient deaths. This review is a collaboration between subject matter experts from large and small laboratories and the federal government to evaluate the capability of clinical laboratories to manage biosafety risks and safely test patient specimens. We discuss the complexity of clinical laboratories, including anatomic pathology, and describe how applying current biosafety guidance may be difficult as these guidelines, largely based on practices in research laboratories, do not always correspond to the unique clinical laboratory environments and their specialized equipment and processes. We retrospectively describe the biosafety gaps and opportunities for improvement in the areas of risk assessment and management; automated and manual laboratory disciplines; specimen collection, processing, and storage; test utilization; equipment and instrumentation safety; disinfection practices; personal protective equipment; waste management; laboratory personnel training and competency assessment; accreditation processes; and ethical guidance. Also addressed are the unique biosafety challenges successfully handled by a Texas community hospital clinical laboratory that performed testing for patients with Ebola without a formal biocontainment unit. The gaps in knowledge and practices identified in previous and ongoing outbreaks demonstrate the need for collaborative, comprehensive solutions to improve clinical laboratory biosafety and to better combat future emerging infectious disease outbreaks.

Working Safely with Vaccinia Virus: Laboratory Technique and Review of Published Cases of Accidental Laboratory Infections with Poxviruses

Vaccinia virus, the prototype Orthopoxvirus, is widely used in the laboratory as a model system to study various aspects of viral biology and virus-host interactions, as a protein expression system, as a vaccine vector, and as an oncolytic agent. The ubiquitous use of vaccinia viruses in laboratories around the world raises certain safety concerns because the virus can be a pathogen in individuals with immunological and dermatological abnormalities, and on occasion can cause serious problems in normal hosts. This chapter reviews standard operating procedures when working with vaccinia virus and reviews published cases of accidental laboratory infections with poxviruses.

Development and implementation of evidence-based laboratory safety management tools for a public health laboratory

We developed an evidence-based continuous quality improvement (CQI) cycle for laboratory safety as a method of utilizing survey data to improve safety in a public health laboratory setting. • Expert Opinion: The CQI cycle begins with the solicitation of laboratory staff input via an annual survey addressing potential chemical, physical and radiological hazards associated with multiple laboratory activities. The survey collects frequency, severity and exposure data related to these activities in the context of the most pathogenic organisms handled at least weekly. • Gap Analysis: Step 2 of the CQI cycle used survey data to identify areas needing improvement. Typically, the traditional two-dimensional risk assessment matrix is used to prioritize mitigations. However, we added an additional dimension - frequency of exposure - to create three-dimensional risk maps to better inform and communicate risk priorities. • Mitigation Measures: Step 3 of the CQI cycle was to use these results to develop mitigations. This included evaluating the identified risks to determine what risk control measures (elimination, substitution, engineering, administrative or PPE) were needed. In the 2016 iteration of the CQI cycle described here, all mitigations were based on administrative controls. • Evaluation and Feedback: The last step of the CQI cycle was to evaluate the inferred effects of interventions through subsequent surveys, allowing for qualitative assessment of intervention effectiveness while simultaneously restarting the cycle by identifying new hazards. Here we describe the tools used to drive this CQI cycle, including the survey tool, risk analysis method, design of interventions and inference of mitigation effectiveness.

Poliovirus containment risks and their management

Aim

Assess risks related to breaches of poliovirus containment.

Method

Using a dynamic transmission model, we explore the variability among different populations in the vulnerability to poliovirus containment breaches as population immunity to transmission declines after oral poliovirus vaccine (OPV) cessation.

Results

Although using OPV instead of wild poliovirus (WPV) seed strains for inactivated poliovirus vaccine (IPV) production offers some expected risk reintroduction of live polioviruses from IPV manufacturing facilities, OPV seed strain releases may become a significant threat within 5-10 years of OPV cessation in areas most conducive to fecal-oral poliovirus transmission, regardless of IPV use.

Conclusions

Efforts to quantify the risks demonstrate the challenges associated with understanding and managing relatively low-probability and high-consequence containment failure events.

Surveillance of laboratory exposures to human pathogens and toxins: Canada 2016

Background

Canada recently enacted legislation to authorize the collection of data on laboratory incidents involving a biological agent. This is done by the Public Health Agency of Canada (PHAC) as part of a comprehensive national program that protects Canadians from the health and safety risks posed by human and terrestrial animal pathogens and toxins.

Objective

To describe the first year of data on laboratory exposure incidents and/or laboratory-acquired infections in Canada since the Human Pathogens and Toxins Regulations came into effect.

Methods

Incidents that occurred between January 1 and December 31, 2016 were self-reported by federally-regulated parties across Canada using a standardized form from the Laboratory Incident Notification Canada (LINC) surveillance system. Exposure incidents were described by sector, frequency of occurrence, timeliness of reporting, number of affected persons, human pathogens and toxins involved, causes and corrective actions taken. Microsoft Excel 2010 was used for basic descriptive analyses.

Results

In 2016, 46 exposure incidents were reported by holders of 835 active licences in Canada representing 1,352 physical areas approved for work involving a biological agent, for an overall incidence of 3.4%. The number of incidents was highest in the academic (n=16; 34.8%) and hospital (n=12; 26.1%) sectors, while the number of reported incidents was relatively low in the private industry sector. An average of four to five incidents occurred each month; the month of September presented as an outlier with 10 incidents.​: A total of 100 people were exposed, with no reports of secondary exposure. Four incidents led to suspected (n=3) or confirmed (n=1) cases of laboratory-acquired infection. Most incidents involved pathogens classified at a risk group 2 level that were manipulated in a containment level 2 laboratory (91.3%). Over 22 different species of human pathogens and toxins were implicated, with bacteria the most frequent (34.8%), followed by viruses (26.1%). Eleven (23.9%) incidents involved a security sensitive biologic agent. Procedure breaches (n=15) and sharps-related incidents (n=14) were the most common antecedents to an exposure. In 10 (21.7%) cases, inadvertent possession (i.e., isolation of an unexpected biological agent during routine work) played a role. Possible improvements to standard operating procedures were cited in 71.7% of incidents. Improvements were also indicated for communication (26.1%) and management (23.9%).

Conclusions

The Laboratory Incident Notification Canada is one of the first surveillance systems in the world to gather comprehensive data on laboratory incidents involving human pathogens and toxins. Exposure incidents reported in the first year were relatively rare, occurring in less than 4% of containment zones within laboratory settings.

From actually toxic to highly specific--novel drugs against poxviruses

The potential use of variola virus, the causative agent of smallpox, as a bioweapon and the endemic presence of monkeypox virus in Africa demonstrate the need for better therapies for orthopoxvirus infections. Chemotherapeutic approaches to control viral infections have been less successful than those targeting bacterial infections. While bacteria commonly reproduce themselves outside of cells and have metabolic functions against which antibiotics can be directed, viruses replicate in the host cells using the cells' metabolic pathways. This makes it very difficult to selectively target the virus without damaging the host. Therefore, the development of antiviral drugs against poxviruses has initially focused on unique properties of the viral replication cycle or of viral proteins that can be selectively targeted. However, recent advances in molecular biology have provided insights into host factors that represent novel drug targets. The latest anti-poxvirus drugs are kinase inhibitors, which were originally developed to treat cancer progression but in addition block egress of poxviruses from infected cells. This review will summarize the current understanding of anti-poxvirus drugs and will give an overview of the development of the latest second generation poxvirus drugs.

Smallpox: what the dermatologist should know

Despite the eradication of naturally occurring smallpox in 1977, stores of the virus have been maintained in laboratories in the United States and Russia. It is feared that certain rogue states and terrorist organizations may have illicitly acquired the virus with the intent of unleashing it as an agent of bioterrorism. The United States and other nations have begun vaccinating individuals in the military and health care workers who might become exposed. Primary care providers and dermatologists will be called upon to evaluate potential index cases and vaccination reactions. In this report, the authors review the essential clinical aspects of smallpox and potential reactions to smallpox vaccination. Special attention is given to eczema vaccinatum, which can occur in vaccinees and their family contacts with active or quiescent atopic dermatitis or a personal history of eczema.

Smallpox vaccination: a review, part I. Background, vaccination technique, normal vaccination and revaccination, and expected normal reactions

Because smallpox could be a factor in bioterrorism, the United States has provided guidelines for smallpox vaccination of certain members of the population, including health care workers and first responders, as well as military personnel. A plan for more extensive vaccination, if it is needed in the event of a bioterrorist attack, is being developed under the aegis of the Centers for Disease Control and Prevention. The characteristics of smallpox vaccine, the technique of administration, and the expected reactions to primary vaccination and revaccination are outlined in this article.

Airborne nosocomial infection: a contemporary perspective

The history of airborne nosocomial infections is reviewed, and current beliefs about such infections are placed into their historical context. Possible sources, both animate and inanimate, of airborne nosocomial infections in the hospital environment are identified. Viruses, bacteria, and fungi that have been important causes of airborne nosocomial infections in the past are discussed, and examples of key studies that have confirmed an airborne route of transmission are presented. Where relevant, measures that have been used to control airborne transmission of nosocomial pathogens are discussed. Although outbreaks of airborne nosocomial infection have been uncommon, airborne transmission appears to account for about 10% of all endemic nosocomial infections.

The smallpox story: life and death of an old disease

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The global eradication of smallpox

On May 8, 1980, the 33rd World Health Assembly declared the world free of smallpox. This followed approximately 2 1/2 years after the last documented naturally occurring case of smallpox was diagnosed in a hospital worker in Merca, Somalia. A major breakthrough for the eventual control of this disease was the discovery of an effective vaccine by Edward Jenner in 1796. In 1966 the World Health Assembly voted a special budget to eliminate smallpox from the world. At that time, smallpox was endemic in more than 30 countries. Mass vaccination programs were successful in many Western countries; however, a different approach was taken in developing countries. This approach was known as surveillance and containment. Surveillance was aided by extensive house-to-house searches and rewards offered for persons reporting smallpox cases. Containment measures included ring vaccination and isolation of cases and contacts. Hospitals played a major role in transmission in a number of smallpox outbreaks. The World Health Organization is currently supporting several control programs and has not singled out another disease for eradication. The lessons learned from the smallpox campaign can be readily applied to other public health programs.

The confirmation and maintenance of smallpox eradication

In December 1979, an independent scientific commission certified global eradication of smallpox. This conclusion was accepted at the 33d World Health Assembly of the World Health Organization (WHO) in May 1980. After WHO's intensified eradication program began in 1967, special certification procedures were used in 35 countries where the disease had been endemic and in 44 others at special risk. Six laboratories are known to retain variola virus; efforts have been made to ensure strict containment of these strains. There is no evidence that smallpox will recur as an endemic disease. Nevertheless, WHO will promote surveillance of smallpox-like disease and selected laboratory research on certain orthopoxviruses. These efforts will maintain confidence that smallpox has been eradicated and confirm that there are no animal reservoirs of variola virus. A more complete understanding of the orthopoxviruses, including monkeypox virus, should also be obtained.