The state of integrated disease surveillance in seven countries: a synthesis report.

OBJECTIVES: Integrated disease surveillance (IDS) offers the potential for better use of surveillance data to guide responses to public health threats. However, the extent of IDS implementation worldwide is unknown. This study sought to understand how IDS is operationalized, identify implementation challenges and barriers, and identify opportunities for development. STUDY DESIGN: Synthesis of qualitative studies undertaken in seven countries. METHODS: Thirty-four focus group discussions and 48 key informant interviews were undertaken in Pakistan, Mozambique, Malawi, Uganda, Sweden, Canada, and England, with data collection led by the respective national public health institutes. Data were thematically analysed using a conceptual framework that covered governance, system and structure, core functions, finance and resourcing requirements. Emerging themes were then synthesised across countries for comparisons. RESULTS: None of the countries studied had fully integrated surveillance systems. Surveillance was often fragmented, and the conceptualization of integration varied. Barriers and facilitators identified included: 1) the need for clarity of purpose to guide integration activities; 2) challenges arising from unclear or shared ownership; 3) incompatibility of existing IT systems and surveillance infrastructure; 4) workforce and skills requirements; 5) legal environment to facilitate data sharing between agencies; and 6) resourcing to drive integration. In countries dependent on external funding, the focus on single diseases limited integration and created parallel systems. CONCLUSIONS: A plurality of surveillance systems exists globally with varying levels of maturity. While development of an international framework and standards are urgently needed to guide integration efforts, these must be tailored to country contexts and guided by their overarching purpose.

Public health genomics capacity assessment: readiness for large-scale pathogen genomic surveillance in Canada's public health laboratories.

BACKGROUND: Along with rapid diagnostic testing, contact tracing, and public health measures, an effective pandemic response incorporates genomics-based surveillance. Large-scale SARS-CoV-2 genome sequencing is a crucial component of the global response to COVID-19. Characterizing the state of genomics readiness among Canada's public health laboratories was necessary to inform strategic planning and deployment of capacity-building resources in the early stages of the pandemic. METHODS: We used a qualitative study design and focus group discussions, encompassing both technical and leadership perspectives, to perform an in-depth evaluation of the state of pathogen genomics readiness in Canada. RESULTS: We found substantial diversity in the state of readiness for SARS-CoV-2 genomic surveillance across Canada. Despite this variability, we identified common barriers and needs in the areas of specimen access, data flow and sharing, computing infrastructure, and access to highly qualified bioinformatics personnel. CONCLUSIONS: These findings enable the strategic prioritization and deployment of resources to increase Canada's ability to perform effective public health genomic surveillance for COVID-19 and prepare for future emerging infectious diseases. They also provide a unique qualitative research model for use in capacity building.

CPHLN recommendations for the laboratory detection of Shiga toxin-producing Escherichia coli (O157 and non-O157).

Shiga toxin-producing Escherichia coli (STEC) are important enteric pathogens responsible for sporadic cases and outbreaks of gastroenteritis. E.coli O157:H7/NM (STEC O157) are the most commonly known STEC serotypes but it is now increasingly apparent that non-O157 STEC serotypes have been underreported in the past because they were not part of routine screening in many front-line laboratories. The Canadian Public Health Laboratory Network (CPHLN) has identified the need for improved detection and surveillance of non-O157 STEC and has developed the following recommendations to assist in the decision-making process for clinical and reference microbiology laboratories. These recommendations should be followed to the best of a laboratory's abilities based on the availability of technology and resources. The CPHLN recommends that when screening for the agents of bacterial gastroenteritis from a stool sample, front-line laboratories use either a chromogenic agar culture or a culture-independent diagnostic test (CIDT). CIDT options include nucleic acid amplification tests (NAATs) to detect Shiga toxin genes or enzyme immunoassays (EIAs) to detect Shiga toxins. If either CIDT method is positive for possible STEC, laboratories must have a mechanism to culture and isolate STEC in order to support both provincial and national surveillance as well as outbreak investigations and response. These CPHLN recommendations should result in improved detection of STEC in patients presenting with diarrhea, especially when due to the non-O157 serotypes. These measures should enhance the overall quality of healthcare and food safety, and provide better protection of the public via improved surveillance and outbreak detection and response.

Use of Whole Genome Sequencing and Patient Interviews To Link a Case of Sporadic Listeriosis to Consumption of Prepackaged Lettuce.

We report on a case of listeriosis in a patient who probably consumed a prepackaged romaine lettuce-containing product recalled for Listeria monocytogenes contamination. Although definitive epidemiological information demonstrating exposure to the specific recalled product was lacking, the patient reported consumption of a prepackaged romaine lettuce-containing product of either the recalled brand or a different brand. A multinational investigation found that patient and food isolates from the recalled product were indistinguishable by pulsed-field gel electrophoresis and were highly related by whole genome sequencing, differing by four alleles by whole genome multilocus sequence typing and by five high-quality single nucleotide polymorphisms, suggesting a common source. To our knowledge, this is the first time prepackaged lettuce has been identified as a likely source for listeriosis. This investigation highlights the power of whole genome sequencing, as well as the continued need for timely and thorough epidemiological exposure data to identify sources of foodborne infections.

Development and application of MLVA methods as a tool for inter-laboratory surveillance.

Multiple-locus variable-number of tandem-repeats analysis (MLVA) has emerged as a valuable method for subtyping bacterial pathogens and has been adopted in many countries as a critical component of their laboratory-based surveillance. Lack of harmonisation and standardisation of the method, however, has made comparison of results generated in different laboratories difficult, if not impossible, and has therefore hampered its use in international surveillance. This paper proposes an international consensus on the development, validation, nomenclature and quality control for MLVA used for molecular surveillance and outbreak detection based on a review of the current state of knowledge.

Subtyping of a large collection of historical Listeria monocytogenes strains from Ontario, Canada, by an improved multilocus variable-number tandem-repeat analysis (MLVA).

Listeria monocytogenes is responsible for severe and often fatal food-borne infections in humans. A collection of 2,421 L. monocytogenes isolates originating from Ontario's food chain between 1993 and 2010, along with Ontario clinical isolates collected from 2004 to 2010, was characterized using an improved multilocus variable-number tandem-repeat analysis (MLVA). The MLVA method was established based on eight primer pairs targeting seven variable-number tandem-repeat (VNTR) loci in two 4-plex fluorescent PCRs. Diversity indices and amplification rates of the individual VNTR loci ranged from 0.38 to 0.92 and from 0.64 to 0.99, respectively. MLVA types and pulsed-field gel electrophoresis (PFGE) patterns were compared using Comparative Partitions analysis involving 336 clinical and 99 food and environmental isolates. The analysis yielded Simpson's diversity index values of 0.998 and 0.992 for MLVA and PFGE, respectively, and adjusted Wallace coefficients of 0.318 when MLVA was used as a primary subtyping method and 0.088 when PFGE was a primary typing method. Statistical data analysis using BioNumerics allowed for identification of at least 8 predominant and persistent L. monocytogenes MLVA types in Ontario's food chain. The MLVA method correctly clustered epidemiologically related outbreak strains and separated unrelated strains in a subset analysis. An MLVA database was established for the 2,421 L. monocytogenes isolates, which allows for comparison of data among historical and new isolates of different sources. The subtyping method coupled with the MLVA database will help in effective monitoring/prevention approaches to identify environmental contamination by pathogenic strains of L. monocytogenes and investigation of outbreaks.

Characterization of antimicrobial resistance, molecular and phage types of Salmonella enterica serovar Typhi isolations.

Isolation rates in Canada of Salmonella enterica serovar Typhi increased from 0.29 to 0.55 isolations/100,000 population during 2000-2006. Although no ciprofloxacin resistance was detected, nalidixic acid resistance increased from 41% to 80%. Multidrug-resistant S. Typhi represented 18% of the strains tested. Pulsed-field gel electrophoresis (PFGE) analysis of 222 isolates resulted in 91 distinct patterns clustering into four major genetic similarity groups. The five most frequently occurring PFGE patterns accounted for 46% of the isolates. Drug-resistant isolates predominantly occurred in one PFGE similarity group. There were 39 phage types identified in 826 isolates analysed with 60% described by five phage types; 134 were untypable. The phage types associated with multidrug resistance were phage types 53, B1, D1, E1, E9, G3 and M1. Improved integration of epidemiological and laboratory case data will facilitate the protection of public health in Canada during an era of increasing travel and globalization.

Surveillance for Listeria monocytogenes and listeriosis, 1995-2004.

Canadian cases and outbreaks of illness caused by Listeria monocytogenes between 1995 and 2004 were assessed. Isolates (722 total) were characterized by serotyping, and pulsed-field gel electrophoresis (PFGE) was performed to provide a means of detecting case clusters. Rates of listeriosis remained fairly consistent during the period of study, and patient characteristics were similar to those seen in studies of other populations. Most isolates were obtained from blood and cerebrospinal fluid, although during some outbreak investigations isolates were also obtained from stools. Serotype 1/2a predominated in isolates from patients in Canada, followed by serotypes 4b and 1/2b. Outbreaks caused by L. monocytogenes that occurred during the period of study were caused by isolates with serotypes 1/2a and 4b. A retrospective analysis of PFGE data uncovered several clusters that might have represented undetected outbreaks, suggesting that comprehensive prospective PFGE analysis coupled with prompt epidemiological investigations might lead to improved outbreak detection and control.

Occurrence and characterization of Salmonella from chicken nuggets, strips, and pelleted broiler feed.

Raw, frozen chicken nuggets and strips have been identified as a significant risk factor in contracting foodborne salmonellosis. Cases of salmonellosis as a result of consuming partly cooked chicken nuggets may be due in part to Salmonella strains originating in broiler feed. This study was undertaken to determine the occurrence and characterize the strains of Salmonella contaminating chicken nuggets, strips, and pelleted feeds, in an attempt to demonstrate whether the same Salmonella strains present in broiler feed could be isolated from raw, frozen chicken nuggets and strips available for human consumption. Salmonellae were recovered using the Health Canada MFHPB-20 method for the isolation and identification of Salmonella from foods. Strains were characterized by serotyping, phage typing, antimicrobial resistance typing (R-typing), and by pulsed-field gel electrophoresis (PFGE). Salmonellae were isolated from 25-g samples in 27% (n=92) of nugget and strip samples, 95% (n=20) of chicken nugget meat samples, and from 9% (n=111) of pelleted feed samples. Salmonella Heidelberg, Salmonella Enteritidis, and Salmonella Orion were the most commonly isolated serovars from chicken nuggets and strips, nugget and strip meat, and pelleted broiler feeds, respectively. Salmonella Enteritidis phage type (PT) 13a with PFGE pattern SENXAI.0006 and R-type sensitive as well as Salmonella Enteritidis PT13a with PFGE pattern SENXAI.0068 and R-type sensitive were isolated from pelleted feed, and chicken nugget and strip meat in two separate instances. Data showed that Salmonella strains isolated from broiler feed were indistinguishable from strains isolated from packaged raw, frozen chicken nuggets and strips. However, results did not rule out the possibility that breeding stock or contamination during processing may have contributed to chicken meat contamination by Salmonella.

Correlations between molecular subtyping and serotyping of Listeria monocytogenes.

To define relationships between Listeria monocytogenes genetic lineages, ribotypes, and serotypes, 235 L. monocytogenes isolates were characterized by serotyping and automated EcoRI ribotyping. Genetic lineage predicted the following serovar clusters: lineage I, comprising serotypes 1/2b, 3b, 3c, and 4b; lineage II, comprising serotypes 1/2a, 1/2c, and 3a; and lineage III, comprising serotypes 4a and 4c. Some EcoRI ribotypes contained multiple serotypes; a subset of these isolates was further differentiated with PvuII ribotyping. Of the 12 resultant EcoRI-PvuII combination types, only 4 contained multiple serotypes, demonstrating the potential of ribotyping for serotype prediction.

Biogenic amines in vacuum-packaged and carbon dioxide-controlled atmosphere-packaged fresh pork stored at -1.50 degrees C.

Biogenic amines are formed in foods as a result of amino acid decarboxylation catalyzed by bacterial enzymes. When consumed in sufficient quantities, these compounds will cause headache, hypertension, fever, and heart failure. Technologies such as vacuum packaging and carbon dioxide-modified atmosphere packaging (CO2-MAP), when combined with low-temperature storage (-1.5 degrees C), allow fresh pork to have a storage life long enough for export to overseas markets. During low-temperature storage of pork in these packaging systems, the lactic acid bacteria (LAB), which possess the enzymes for biogenic amine formation, dominate the microflora. The objectives of this study were to determine the quantities of biogenic amines in packaged fresh pork, to monitor LAB growth, and to determine the storage life by sensory evaluation. Vacuum-packaged and CO2-MAP pork were stored at -1.5+/-0.5 degrees C for 9 and 13 weeks, respectively. Phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine, and spermine concentrations were determined weekly by high-performance liquid chromatography and capillary gel electrophoresis. LAB and carnobacteria were enumerated weekly. Samples were evaluated for odor and appearance. The CO2-MAP was successful in delaying bacterial growth and the development of unacceptable off-odors compared with the vacuum packaging. The storage lives of the vacuum-packaged and CO2-MAP pork were 5 and 13 weeks, respectively. High-performance liquid chromatography was the superior method for biogenic amine quantification. Tyramine and phenylethylamine in pork of both packaging treatments approached levels considered to be potentially toxic. Given Canada's increasing role in the export of fresh meat to foreign markets, it is recommended that the formation of biogenic amines in vacuum-packaged and CO2-MAP pork be further investigated.

Discharge of mothers and babies from hospital after birth of a healthy full-term infant: developing criteria through a community-wide consensus process.

OBJECTIVE: To ensure safe care of mothers and babies after birth, irrespective of length of hospital stay, and to ensure effective links between hospital and community postnatal services. METHODS: Program aimed toward consumers and professionals working with them in Ottawa-Carleton (750,000 persons.) All pregnant women in the community included. Program developed by professionals, institutions and community agencies. Information on current practices elsewhere and early discharge literature studied. New provincial survey on practice changes performed in Ontario. Emergency room utilization data analyzed. Discharge and post-discharge criteria, and a common prenatal education curriculum, developed. RESULTS: Multidisciplinary, multi-sectoral committees, institutions and agencies have developed programs for appropriate discharge practice and improved postnatal follow-up. Professionals have supported flexible discharge guidelines. CONCLUSIONS: Provided discharge criteria and follow-up are available, flexible discharge timing and safety appear compatible. The Ottawa-Carleton process to develop criteria and programs has allowed a collaborative, consensus-based approach to 'early' newborn discharge.

Promoting first trimester prenatal classes: a survey.

In June 1990, 436 women and their spouses attending prenatal classes in the Ottawa-Carleton region completed a self-administered questionnaire to identify use of and interest in first trimester prenatal classes, and possible contact points with women to encourage early prenatal class attendance. Only 23% of the women had attended classes during the first trimester, but another 39% said they would have been interested. Two major categories of deterrents to early prenatal class attendance were found: 1) low level of public knowledge about availability and usefulness and 2) low physician patient referral. Most (89.4%) women went to their physician early in pregnancy, and many (45.7%) found out they were pregnant through the drug store. Suggested approaches to promoting first trimester attendance at prenatal classes include public awareness campaigns through pharmacies, the workplace and in the general community, and education programs for physicians about the importance of referral to early classes.

Effectiveness of a pregnancy smoking cessation program.

OBJECTIVE: To evaluate two nursing approaches to promoting smoking cessation during initial antenatal visits. DESIGN: Experimental, with assignment to interventions using a random, alternate-day strategy and blind assessment of smoking at baseline, 1 month postintervention, 36 weeks' gestation, and 6 weeks postpartum. SETTING/PARTICIPANTS: 224 daily smokers, fewer than 31 weeks gestation, during first prenatal visit, at a teaching hospital antenatal clinic. INTERVENTIONS: An evening class providing guidance on a self-help program for 2 hours on a group basis or 20 minutes on an individual basis during the prenatal appointment. MAIN OUTCOME MEASURE: Smoking cessation, confirmed by urinary cotinine levels. RESULTS: All women assigned to the referral intervention received a referral, but none attended the classes. In contrast, 93% assigned to the immediate intervention received the intervention. The group receiving immediate intervention had two to three times higher rates of cessation at all follow-up periods, with significant differences at the 1-month follow-up. There were certain similarities between the groups. CONCLUSION: Cessation interventions should be administered during the first prenatal visit.

The hospital liaison process: identifying risk factors in postnatal multiparas.

Postnatal home visiting has been a routine part of the public health nurse's role in Canada for decades. Resource limitations in recent years have required Health Units to justify programming choices and in some cases have dictated a shift toward more intensive service provision to high risk clients. This study examined the screening accuracy of a tool developed for use by hospital liaison nurses to identify multiparas in need of home visiting. Results showed poor agreement between client information collected by the hospital liaison nurse and the assessment done by the PHN in the clients' home, even when explicit referral criteria were used. Changes are required in the referral process to effectively screen postnatal clients in need of further services.