Community-based Outbreaks Research Articles

Preventing Measles in Immunosuppressed Cancer and Hematopoietic Cell Transplantation Patients: A Position Statement by the American Society for Transplantation and Cellular Therapy.

Until recently, measles exposures were relatively rare and so, consequently, were an afterthought for cancer patients and/or blood and marrow transplant recipients and their providers. Declines in measles herd immunity have reached critical levels in many communities throughout the United States due to increasing vaccine hesitancy, so that community-based outbreaks have occurred. The reemergence of measles as a clinical disease has raised serious concerns among immunocompromised patients and those who work within the cancer and hematopoietic cell transplantation (HCT) community. Since live attenuated vaccines, such as measles, mumps, and rubella (MMR), are contraindicated in immunocompromised patients, and with no approved antiviral therapies for measles, community exposures in these patients can lead to life-threatening infection. The lack of data regarding measles prevention in this population poses a number of clinical dilemmas. Herein specialists in Infectious Diseases and HCT/cellular therapy endorsed by the American Society of Transplant and Cellular Therapy address frequently asked questions about measles in these high-risk cancer patients and HCT recipients and provide expert opinions based on the limited available data.

Management of meningococcal outbreaks: are we using the same language? Comparison of the public health policies between high-income countries with low incidence of meningococcal disease

ABSTRACTBackground: Invasive meningococcal disease (IMD) in high-income countries usually occurs sporadically with low incidence and occasionally as small clusters or outbreaks.The WHO guidelines (GLs) for IMD outbreak applies only to African countries with high endemic incidence. Several high-income countries developed their own GLs on IMD outbreak, and we compare their terminology, classification, definitions, and public health interventions.Methods: National IMD outbreak GLs of the European Union and the Organisation for Economic Co-operation and Development member states were compared. Due to linguistic barriers, 17 out of forty-one countries were selected, and the GLs on the websites of the national health authorities were independently screened by two researchers.Results: National GLs on IMD outbreak were available for 12 countries. All GLs classify IMD outbreak into organization and community based using different terminology (cluster, epidemic, etc.). Two GLs introduce also a third condition of hyperendemic. Definitions, thresholds, and countermeasures vary among countries.Conclusions: Different definitions of organization and community-based outbreaks and countermeasures are expected because of uncertainties about their effectiveness, and differences between countries in health-care systems and public health policy approaches.Nevertheless, variations in terminology, definitions and countermeasures are confusing and reflect the need for an international standardization.

Community outbreak of invasive group A streptococcus infection in Ontario, Canada.

Outbreaks of invasive group A streptococcal infection (iGAS) have historically occurred in institutional settings. Increasingly, community-based outbreaks have been reported, often among marginalized populations, yet few guidelines exist for managing iGAS outbreaks in such settings. To describe the ongoing outbreak of iGAS in Middlesex-London, Ontario, and the challenges that arose while applying current guidelines to a marginalized population in a community setting. The outbreak investigation included all iGAS cases in Middlesex-London with an onset date from April 1, 2016 to February 28, 2018. Clinical specimens were submitted to provincial and federal laboratories for typing. Public health management of the outbreak involved environmental health inspections, contact tracing, chemoprophylaxis of close contacts, swabbing to determine colonization rates of Streptococcus pyogenes, and communicating with stakeholders and the public. A total of 156 confirmed cases of iGAS corresponding to 147 individuals were reported in less than two years. More than 60% of cases occurred in men (n=91) and almost half (n=71) of the total number of cases were persons who used drugs (PWUD) and/or were under-housed. Of the PWUD cases, 58 of 65 (89%) used injection drugs. Key challenges in controlling this outbreak included reaching PWUD and under-housed people; completing a case history and contact list; facilitating completion of treatment; dealing with concurrent infections such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV); and optimizing environmental health conditions. Guidelines were adapted so contacts who shared drugs or injection drug equipment with a known iGAS case would be offered chemoprophylaxis regardless of the clinical severity of the case. To optimize treatment completion, a single-dose of azithromycin for individuals in close contact with PWUD and/or under-housed cases was given. Cases with macrolide-resistant strain emm9 have recently emerged. The application of institution-based guidelines for iGAS outbreaks has been ineffective in controlling this particular community outbreak. There is a need for guidelines on managing outbreaks of iGAS in the community especially when an outbreak involves marginalized populations.

Epidemiology of Meningococcal Disease Outbreaks in the United States, 2009-2013.

Although the incidence of meningococcal disease is low in the United States, outbreaks remain a serious public health concern. In this evaluation, we identify and describe outbreaks of meningococcal disease. A retrospective review of all meningococcal disease cases reported from 1 January 2009 to 31 December 2013 was performed by state health departments and the Centers for Disease Control and Prevention to identify meningococcal disease outbreaks. An outbreak was defined as ≥2 primary cases of the same serogroup within <3 months in an organization, or a ≥2-fold increase in disease rates in a community. From 2009 to 2013, a total of 3686 cases of meningococcal disease were reported in the United States. Among these, 180 primary cases (4.9%) occurred as part of 36 outbreaks (17 organization-based and 19 community-based). Serogroup B accounted for 8 (47.1%) of the organization-based outbreaks, including 6 of 8 university outbreaks. Serogroup C accounted for 10 (52.6%) of the community-based outbreaks, including both of 2 outbreaks identified among men who have sex with men. Organization- and community-based outbreaks differed in predominant serogroup, age distribution of cases, and clinical syndrome. Among 33 outbreaks with known information, a vaccination and/or expanded chemoprophylaxis campaign was conducted in 16 (48.5%). Outbreak-associated cases account for approximately 5% of all meningococcal disease cases in the United States. Serogroup B is the primary cause of organization-based outbreaks, with the majority of university outbreaks due to serogroup B, and serogroup C is the primary cause of community-based outbreaks.

Deep coal mining and meningococcal meningitis in England and Wales, 1931–38: Ecological study, with implications for deep shaft mining activities worldwide

The hypothesized role of deep coal mining in the development of community-based outbreaks of meningococcal meningitis has gone largely unexplored. Taking the coalfields of Britain as a historical testbed, techniques of linear and binomial logistic regression were used to assess the association between meningococcal meningitis rates and male occupation rates for coal mining in England and Wales during the national epidemic of 1931–32 and in its aftermath. Adjusting for the epidemiological effects of age, residential density, recent changes in the number of families, housing stock and low social class, the analysis yielded evidence of a significant and positive association between coal mining occupation rates and notified levels of meningitis activity in the epidemic period. Communities in areas of the world that currently maintain substantial deep coal extraction industries may be at increased risk for the epidemic transmission of meningococcal meningitis.

Vaccine Hesitancy: In Search of the Risk Communication Comfort Zone.

Introduction:This paper reports the findings of a national online survey to parents of children aged 5 and younger. The objectives of the study were to assess parental understanding of childhood immunizations, identify sources of information that they trust for vaccine-related content, assess where parents with young children stand on the key issues in the public debate about vaccination, and identify which risk communication messages are most effective for influencing the behaviours of vaccine hesitant parents.Methods:A total of 1,000 surveys (closed and open-ended questions) were administered in November 2015 using the Angus Reid Forum Panel, a key consumer panel consisting of approximately 150,000 Canadian adults aged 18 and older, spread across all geographic regions of Canada.Results:Approximately 92% of the Canadian parents surveyed consider vaccines safe and effective, and trust doctors and public health officials to provide timely and credible vaccine-related information. However, a concerning number of them either believe or are uncertain whether there is a link between vaccines and autism (28%), worry that vaccines might seriously harm their children (27%), or believe the pharmaceutical industry is behind the push for mandatory immunization (33%). Moreover, despite the common assumption that social media are becoming the go-to source of health news and information, most parents still rely on traditional media and official government websites for timely and credible information about vaccines and vaccine preventable diseases, particularly during community-based disease outbreaks. Finally, parents reported high levels of support for pro-vaccine messaging that has been demonstrated in previous research to have little to no positive impact on behaviour change, and may even be counterproductive.Discussion:The study’s results are highly relevant in a context where public health officials are expending significant resources to increase rates of childhood immunization and combat vaccine hesitancy. The data offer insight into where parents stand on the political and public debate about mandatory vaccination, what aspects of vaccine science remain uncertain to them, which media and institutional sources they use and trust to navigate the health information environment, how they look for information and whom they trust during periods of health emergency or crisis, and which communication strategies are considered most effective in persuading vaccine hesitant parents to immunize their children.

Hepatitis A Seroprevalence of Employees of A Public Hospital

Objectives: The hepatitis A virus (HAV) is spread through the fecal-oral route. A vaccine is available for this infectious disease that primarily affects the liver, and which may have a more severe course in patients of advanced age. Hepatitis A outbreaks are often observed in places such as hospitals, schools, and long-term care centers. The aim of this study was to determine the seroprevalence in health workers within the risk group according to profession group. Methods: The anti-HAV immunoglobulin G (IgG) seropositivity of health workers at Zeynep Kamil Women's and Children's Disease Training and Research Hospital between January 1, 2012 and February 15, 2014 was evaluated retrospectively. A total of 169 participants were included in the study; 26 were male and 143 were female. Statistical significance was accepted at p<0.05. Results: In all, 109 (64.49%) of those included in the study were anti-HAV-IgG seropositive, while 60 (35.50%) were anti-HAV-IgG seronegative. Of the participants with an anti-HAV-IgG seropositive result, 92 (84.4%) were female and 17 (15.59%) were male. The HAV-IgG-positive rate was found to be significantly higher in the age group of those aged 35 years or more (p<0.05) in this study. Conclusion: HAV infection still ranks first among vaccine-preventable diseases frequently seen. Given the prevalence of the infection, its causing fulminant insufficiency, the large number of people affected in community-based outbreaks, the high risk of infection in some groups, and the cost of infection (hospitalization, loss of labor, prophylaxis after contact), the importance of vaccination is clear.

Control of recent community-based outbreaks of invasive meningococcal disease in men who have sex with men in Europe and the United States

Invasive meningococcal disease (IMD) is an infrequent yet deadly infection that constitutes a public health emergency. Control requires rapid identification and diagnosis of suspect cases, prompt administration of antibiotic prophylaxis to close contacts, and recognition of epidemiological links among cases. In 2011, the incidence rate of IMD was 0.73 per 100,000 in European Union (EU) countries, as reported by Marcus et al. in their report on a recent cluster of serogroup C Neisseria meningitidis (MenC) in MSM in this edition of Eurosurveillance [1], in the United States (US), it was 0.25 per 100,000 (an all-time low). While outbreaks of IMD in the US and EU are rare, they can be difficult to control, particularly when the primary risk factor is membership in a social network rather than an organisation or institution [2]. In September 2012, a slowly evolving outbreak of IMD was recognised among men who have sex with men (MSM) in New York City (NYC). The NYC Department of Health and Mental Hygiene (DOHMH), in collaboration with community providers, implemented a meningococcal vaccine campaign to prevent further illness and death [3]. IMD cases in MSM have recently also been recognised in Germany, France, and Belgium. In response to these clusters the European Centre for Disease Prevention and Control, with input from leading experts, composed and distributed a rapid risk assessment to help guide medical and public health authorities [4]. The report by Marcus et al. in this issue summarises the German cluster and highlights important issues regarding local and international IMD control [1].

Pulmonary Tuberculosis Outbreak in a Pediatric Population

Community-based outbreaks of Mycobacterium tuberculosis are uncommon in the United States but represent a dramatic type of epidemic that can lead to considerable investigations. Most of our knowledge regarding spread of tuberculosis (TB) has accumulated from the study of outbreaks. We describe the most recent outbreak of TB in Genesee County, Michigan. In February 2007, isoniazid-sensitive infectious pulmonary TB was identified in a 45-year-old African American grandmother who frequently provided care for her grandchildren and other children. The source case was reported to the Genesee County Health Department, which started an investigation to identify family and social contacts. We reviewed past medical records of contacts and prioritized them for evaluation based on the period of exposure to the index case. Health department staff screened contacts using clinical evaluation, tuberculin skin test, and chest radiography when indicated. Results were reviewed, and data were analyzed using descriptive inferential and epidemiological statistics.

Community-based outbreaks in vulnerable populations of invasive infections caused by Streptococcus pneumoniae serotypes 5 and 8 in Calgary, Canada.

BackgroundOutbreaks of invasive pneumococcal disease (IPD) typically occur within institutions. Beginning in 2005, we detected an increase in serotype (ST) 5 and ST8 IPD cases, predominantly in homeless persons living in an open community.Methodology/Principal FindingsCASPER (Calgary Area S. pneumoniae Epidemiology Research) surveillance study of all IPD (sterile site isolates) in our region (pop ∼1,100,000). Interviews and chart reviews of all cases and all isolates phenotypically analyzed and selected isolated tested by multi-locus sequence typing (MLST).Conclusions/SignificanceDuring 2005–2007, 162 cases of ST5 IPD and 45 cases of ST8 IPD were identified. The isolates demonstrated phenotypic and genotypic clonality. The ST5 isolates were sequence type (ST) 289 and demonstrated intermediate susceptibility to TMP-SMX. The ST8 isolates were predominantly ST1268, with a susceptible antimicrobial susceptibility profile. Individuals with ST5 IPD were more likely to be middle aged (OR 2.6), homeless (OR 4.4), using illicit drugs(OR 4.8), and asthmatic(OR 2.6). Those with ST8 were more likely to be male (OR 4.4), homeless (OR 2.6), aboriginal (OR7.3), and a current smoker (OR 2.5). Overlapping outbreaks of ST5 and ST8 IPD occurred in an open community in Calgary, Canada and homelessness was a predominant risk factor. Homelessness represents a unique community in which pneumococcal outbreaks can occur.

Utility of the ESSENCE Surveillance System in Monitoring the H1N1 Outbreak

The Electronic Surveillance System for the Early Notification of Community-Based Epidemics (ESSENCE) enables health care practitioners to detect and monitor health indicators of public health importance. ESSENCE is used by public health departments in the National Capital Region (NCR); a cross-jurisdictional data sharing agreement has allowed cooperative health information sharing in the region since 2004. Emergency department visits for influenza-like illness (ILI) in the NCR from 2008 are compared to those of 2009. Important differences in the rates, timing, and demographic composition of ILI visits were found. By monitoring a regional surveillance system, public health practitioners had an increased ability to understand the magnitude and character of different ILI outbreaks. This increased ability provided crucial community-level information on which to base response and control measures for the novel 2009 H1N1 influenza outbreak. This report underscores the utility of automated surveillance systems in monitoring community-based outbreaks. There are several limitations in this study that are inherent with syndrome-based surveillance, including utilizing chief complaints versus confirmed laboratory data, discerning real disease versus those healthcare-seeking behaviors driven by panic, and reliance on visit counts versus visit rates.

Molecular and Epidemiological Characteristics of Norovirus Associated with Community-Based Sporadic Gastroenteritis Incidents and Norovirus Outbreaks in Victoria, Australia, 2002–2007

Objectives: The molecular and epidemiological features of community-based norovirus-associated sporadic gastroenteritis incidents (NASGIs) are poorly understood. This study examined these features and compared the findings with studies of community-based and institutional norovirus-associated gastroenteritis outbreaks (NAGOs). Methods: Fecal specimens from NASGIs and NAGOs that occurred in Victoria, Australia (2002–2007) were tested for norovirus by reverse transcription-polymerase chain reaction methodology. Norovirus genotype was determined by nucleotide sequence analysis. Results: 106 community-based NASGIs, 116 community-based NAGOs and 902 institutional NAGOs were identified. The mean age and gender ratio of individuals associated with community-based NASGIs and community-based NAGOs were similar but differed from that found for institutional NAGOs. Although GII.4 was the predominant genotype associated with all three incident types, the mix of genotypes was similar for community-based NASGIs and community-based NAGOs but that for institutional NAGOs was different. All three incident types had a similar seasonal periodicity due to the pronounced seasonal periodicity of GII.4 incidents. Conclusions: The molecular and epidemiological features of noroviruses associated with community-based NASGIs and community-based NAGOs are similar but are different from those found for institutional NAGOs.

Diversity of noroviruses cocirculating in the north of England from 1998 to 2001.

A study was undertaken to investigate the diversity of noroviruses (NVs) in fecal samples from patients from 529 outbreaks and 141 sporadic cases of gastroenteritis in the North of England from September 1998 to August 2001. NV strains were detected by electron microscopy and characterized by a combination of the Grimsby virus antigen enzyme-linked immunosorbent assay, reverse transcriptase PCR, the heteroduplex mobility assay, and DNA sequencing. Twenty-one distinct NV strains, including several novel or variant strains not seen previously, were found circulating in the population studied. Genogroup II NVs were responsible for 83% of the outbreaks. Several strains cocirculated at any one time. The Bristol (Grimsby/Lordsdale) and Hawaii (Girlington) genotypes were the most prevalent among the NVs identified, detected in 49 and 20% of the outbreaks, respectively. A limited number of other genogroup II and I strains were cocirculating. The virus populations detected in hospitals and nursing homes were distinct from those found in community-based outbreaks. Outbreaks in hospitals and nursing homes were more likely to be caused by genogroup II strain Grimsby or Girlington (P < 0.0001) than by other genogroup II or I strains.

Management of hospital outbreaks of gastro-enteritis due to small roundstructured viruses: Report of the public health laboratory service viral gastro enteritis working group

Small round structured viruses (SRSVs, Norwalk-like viruses, NLVs) are the most common cause of outbreaks of gastro-enteritis in hospitals and also cause outbreaks in other settings such as schools, hotels, nursing homes and cruise ships. Hospital outbreaks often lead to ward closure and major disruption in hospital activity. Outbreaks usually affect both patients and staff, sometimes with attack rates in excess of 50%. For this reason, staff shortages can be severe, particularly if several wards are involved at the same time. SRSVs may be spread by several routes: faecal–oral; vomiting/aerosols; food and water. Viruses may be introduced into the ward environment by any of these routes and then propagated by person-to-person spread. In an outbreak setting, the diagnosis can usually be made rapidly and confidently on clinical and epidemiological grounds, particularly if vomiting is a prominent symptom. By the time an SRSV outbreak has been recognized at ward level, most susceptible individuals will have been exposed to the virus and infection control efforts must prioritize the prevention of spread of infection to other clinical areas bycontainment of infected/exposed individuals (especially the prevention of patient and staff movements to other areas), hand-hygiene and effective environmental decontamination.This report of the Public Health Laboratory Service Viral Gastro-enteritis Working Group reviews the epidemiology of outbreaks of infection due to SRSVs and makes recommendations for their management in the hospital setting. The basic principles which underpin these recommendations will also be applicable to the management of some community-based institutional outbreaks.

A Method for Extraction of High-Quality and High-Quantity Genomic DNA Generally Applicable to Pathogenic Bacteria

In this study, we report a modified procedure for extraction of high-quality genomic DNA that is rapid, simple, biologically nonhazardous, and generally applicable to pathogenic bacteria. Bacterial cells were pretreated with 70% ethanol prior to enzymatic digestion with lysozyme. Exposure of bacterial cells to 70% ethanol sterilized the cultures, making the process biologically safe and increased the susceptibility of the cells to lysozyme-induced lysis. Consistently high yields of genomic DNA (mean average yield, 0.5–2.5 mg/ml) were obtained from 465 isolates representing over 30 clinically important bacterial species. Genomic DNA obtained was determined to be suitable for further analysis, including bacterial fingerprinting techniques like restriction endonuclease analysis, Southern hybridization, and repetitive PCR. Availability of a generally applicable procedure for extraction of high-quality and high-quantity genomic DNA would be immensely beneficial for laboratories engaged in molecular surveillance of nosocomial and community-based outbreaks.

Community-Based Outbreaks of Tuberculosis

Numerous recent reports have detailed outbreaks of tuberculosis in hospitals and other congregate settings. The characteristics of such settings, including high concentrations of infectious patients and immunocompromised hosts, the potential for sustained daily contact for weeks and often months, and improper precautions taken for protection, make them well suited for tuberculosis transmission. However, community-based outbreaks, which are the source of much public concern, have not been reviewed since 1964, when 109 community outbreaks were examined. Since few of the characteristics of institutional settings are present in the community, the lessons learned may not be applicable to community-based outbreaks. Furthermore, recent studies with analysis by restriction fragment length polymorphisms have documented unexpectedly high rates of primary disease in certain urban communities, suggesting that our understanding of community-based transmission may be incomplete. We reviewed all reported community-based outbreaks of tuberculosis occurring in the last 30 years to assess the basis of our current understanding of community-based transmission. More than 70 outbreaks were identified, with schools being the most common site. In most, a delay in diagnosis, sustained contact with the index case, inadequate ventilation, or overcrowding was contributory. We conclude that community-based outbreaks of tuberculosis continue to occur and that well-established risks contribute to most outbreaks. Many outbreaks can be prevented or limited by attention to basic infection control principles.

Community-based outbreaks of tuberculosis

Community-based outbreaks of tuberculosis