International Public Health Agencies Research Articles

Comparison of the analytical sensitivity of COVID-19 rapid antigen tests in Australia and Canada

Rapid testing has become an indispensable strategy to identify the most infectious individuals and prevent the transmission of SARS-CoV-2 in vulnerable populations. As such, COVID-19 rapid antigen tests (RATs) are being manufactured faster than ever yet lack relevant comparative analyses required to inform on absolute analytical sensitivity and performance, limiting end-user ability to accurately compare brands for decision making. To date, more than 1000 different COVID-19 RATs are commercially available in the world, most of which detect the viral nucleocapsid protein (NP). Here, we examine and compare the analytical sensitivity of 26 RATs that are readily available in Canada and/or Australia using two NP reference materials (RMs) – a fluorescent NP-GFP expressed in bacterial cells and NCAP-1 produced in a mammalian expression system. Both RMs generate highly comparable results within each RAT, indicating minimal bias due to differing expression systems and final buffer compositions. However, we demonstrate orders of magnitude differences in analytical sensitivities among distinct RATs, and find little correlation with the median tissue culture infectious dose (TCID50) assay values reported by manufacturers. In addition, two COVID-19/Influenza A&B combination RATs were evaluated with influenza A NP-GFP. Finally, important logistics considerations are discussed regarding the robustness, ease of international shipping and safe use of these reference proteins. Taken together, our data highlight the need for and practicality of readily available, reliable reference proteins for end-users that will ensure that manufacturers maintain batch-to-batch quality and accuracy of RATs. They will aid international public health and government agencies, as well as health and aged care facilities to reliably benchmark and select the best RATs to curb transmission of future SARS-CoV-2 and influenza outbreaks.

Public face mask use during the COVID-19 pandemic in Auckland, New Zealand

Abstract Aim Public health officials recommended the use of face masks by the population to combat the transmission of COVID-19. Studies on self-reported behaviour are a poor substitute for assessing adherence to government recommendations. This study aimed to determine the percentage of pedestrians wearing masks in the Central Business District (CBD) and a suburb of Auckland, New Zealand (NZ). Methods This direct observational study of pedestrians crossing two busy intersections occurred between 22 August 2020 and 7 March 2022. Data collection occurred at three separate times during the day, in the morning (from 8 to 9 am), noon (from 12 to 1 pm) and afternoon (from 4 to 5 pm) for precisely one hour each time. Results Over 12 days of COVID alert level restrictions, we observed 30,855 pedestrians. Overall, 57.9% of pedestrians wore a mask outdoors. Masks-wearing was significantly higher in the CBD (64.0%) than in the suburb (38.7%), p < 0.001. Masks use was lower in the morning (51.1%) than at noon (56.1%) or afternoon (62.7%), p < 0.001, both in the CBD and the suburb. Conclusion This was the first observational study in NZ examining the public’s mask use during the COVID-19 pandemic. From our observations, there may be opportunities for improvement in public face mask use rates to decrease the spread of COVID-19 in the population. In addition, our findings can inform national and international public health agencies about face mask uptake in public.

Call for Special Feature Papers: Threat Agnostic Approaches to Biodefense and Public Health.

Call for Special Feature Papers: Threat Agnostic Approaches to Biodefense and Public Health.

Aiming for the end of the COVID-19 pandemic: the what, how, who, where, and when.

Aiming for the end of the COVID-19 pandemic: the what, how, who, where, and when.

Safety of varicella vaccination strategies: An overview of reviews.

The safety of new vaccines under development as well as existing vaccines is a key priority for national and international public health agencies. A number of countries have implemented universal childhood varicella vaccination programmes over the past 30years. However, strategies differ in terms of the number of doses, type of vaccine(s) recommended, age at vaccination and interval between doses for a two-dose schedule. An overview of reviews was undertaken to assess the existing systematic review evidence of the safety of varicella vaccination strategies. The review was restricted to immunocompetent children aged 9months to 6years inclusive. A comprehensive search of databases, registries and grey literature was conducted up to 2 February 2022. Two reviewers independently screened, extracted data and assessed the methodological quality of included reviews. Overlap of included reviews was also assessed. A total of 17 reviews, incorporating both the monovalent varicella only and quadrivalent measles-mumps-rubella-varicella (MMRV) vaccines were included in the overview; six assessed the safety of one-dose strategies, four assessed the safety of two-dose strategies and 14 reviews did not specify the dosing strategy. The evidence suggests that mild local and systemic reactions are relatively common with varicella vaccination. Febrile seizures are also possible adverse effects of both the monovalent and quadrivalent MMRV vaccine, but serious adverse reactions are rare. While most reviews contained methodological flaws, and analysis by vaccine type and dosing strategy was restricted due to lack of detail in reporting of the reviews, there was clear and consistent evidence from a substantial evidence base, comprising 34 randomised controlled trials and 62 other primary studies/reviews, that varicella vaccination is safe.

SARS-CoV-2 Catalonia contact tracing program: evaluation of key performance indicators

BackgroundGuidance on SARS-CoV-2 contact tracing indicators have been recently revised by international public health agencies. The aim of the study is to describe and analyse contact tracing indicators based on Catalonia’s (Spain) real data and proposing to update them according to recommendations.MethodsRetrospective cohort analysis including Catalonia’s contact tracing dataset from 20 May until 31 December 2020. Descriptive statistics are performed including sociodemographic stratification by age, and differences are assessed over the study period.ResultsWe analysed 923,072 contacts from 301,522 SARS-CoV-2 cases with identified contacts (67.1% contact tracing coverage). The average number of contacts per case was 4.6 (median 3, range 1–243). A total of 403,377 contacts accepted follow-up through three phone calls over a 14-day quarantine period (84.5% of contacts requiring follow-up). The percentage of new cases declared as contacts 14 days prior to diagnosis evolved from 33.9% in May to 57.9% in November. All indicators significantly improved towards the target over time (p < 0.05 for all four indicators).ConclusionsCatalonia’s SARS-CoV-2 contact tracing indicators improved over time despite challenging context. The critical revision of the indicator’s framework aims to provide essential information in control policies, new indicators proposed will improve system delay’s follow-up. The study provides information on COVID-19 indicators framework experience from country’s real data, allowing to improve monitoring tools in 2021–2022. With the SARS-CoV-2 pandemic being so harmful to health systems and globally, is important to analyse and share contact tracing data with the scientific community.

Zika Virus Prediction Using AI-Driven Technology and Hybrid Optimization Algorithm in Healthcare.

The Zika virus presents an extraordinary public health hazard after spreading from Brazil to the Americas. In the absence of credible forecasts of the outbreak's geographic scope and infection frequency, international public health agencies were unable to plan and allocate surveillance resources efficiently. An RNA test will be done on the subjects if they are found to be infected with Zika virus. By training the specified characteristics, the suggested Hybrid Optimization Algorithm such as multilayer perceptron with probabilistic optimization strategy gives forth a greater accuracy rate. The MATLAB program incorporates numerous machine learning algorithms and artificial intelligence methodologies. It reduces forecast time while retaining excellent accuracy. The projected classes are encrypted and sent to patients. The Advanced Encryption Standard (AES) and TRIPLE Data Encryption Standard (TEDS) are combined to make this possible (DES). The experimental outcomes improve the accuracy of patient results communication. Cryptosystem processing acquires minimal timing of 0.15 s with 91.25 percent accuracy.

Lessons for and from the COVID-19 pandemic response — An appraisal of guidance for the public health management of Invasive Meningococcal Disease

BackgroundCOVID-19 has focussed public attention on the management of communicable disease like never before. Surveillance, contact tracing, and case management are recognised as key components of outbreak prevention. Development of guidance for COVID-19 has drawn from existing management of other communicable diseases, including Invasive Meningococcal Disease (IMD). IMD is a rare but severe outcome of Neisseria meningitidis infection that can be prevented through vaccination. Cases still occur sporadically, requiring ongoing surveillance and consistent management. To this end, national and international public health agencies have developed and published guidance for identification and management of IMD cases. AimTo assess national and international guidelines for the public health management of IMD, with a focus on the recommendations for identification and management of “close contacts” to IMD cases. MethodsGuidelines from six national and international public health agencies were assessed using a modified version of the Appraisal of Guidelines, Research and Evaluation (AGREE II) Instrument in four key domains: stakeholder involvement, developmental rigour, clarity, and applicability. A direct comparison of terminology and recommendations for identification and management of close contacts to IMD cases was also conducted. ResultsGuidelines from Europe and the United Kingdom rated most highly using the AGREE II Instrument, both presenting a clear, critical assessment of the strength of the available evidence, and the risks, costs, and benefits behind recommendations for management of close contacts. Direct comparison of guidelines identified inconsistencies in the language defining close contacts to IMD cases. ConclusionDiscrepancies between guidelines could be due to limited evidence concerning mechanisms behind disease transmission, along with the lack of a consistent process for development and review of guideline recommendations. COVID-19 management has demonstrated that international collaboration for development of public health guidance is possible, a practice that should be extended to management of other communicable diseases.

Aspartame and cancer \u2013 new evidence for causation

BackgroundAspartame is one of the world’s most widely used artificial sweeteners and is an ingredient in more than 5000 food products globally. A particularly important use is in low-calorie beverages consumed by children and pregnant women.The Ramazzini Institute (RI) reported in 2006 and 2007 that aspartame causes dose-related increases in malignant tumors in multiple organs in rats and mice. Increased cancer risk was seen even at low exposure levels approaching the Acceptable Daily Intake (ADI). Prenatal exposures caused increased malignancies in rodent offspring at lower doses than in adults.These findings generated intense controversy focused on the accuracy of RI’s diagnoses of hematopoietic and lymphoid tissue tumors (HLTs). Critics made the claim that pulmonary lesions observed in aspartame-exposed animals were inflammatory lesions caused by Mycoplasma infection rather than malignant neoplasms.MethodsTo address this question, RI subjected all HLTs from aspartame-exposed animals to immunohistochemical analysis using a battery of markers and to morphological reassessment using the most recent Internationally Harmonized Nomenclature and Diagnostic (INHAND) criteria.FindingsThis immunohistochemical and morphological re-evaluation confirmed the original diagnoses of malignancy in 92.3% of cases. Six lesions originally diagnosed as lymphoma (8% of all HLTs) were reclassified: 3 to lymphoid hyperplasia, and 3 to chronic inflammation with fibrosis. There was no evidence of Mycoplasma infection.InterpretationThese new findings confirm that aspartame is a chemical carcinogen in rodents. They confirm the very worrisome finding that prenatal exposure to aspartame increases cancer risk in rodent offspring. They validate the conclusions of the original RI studies.These findings are of great importance for public health. In light of them, we encourage all national and international public health agencies to urgently reexamine their assessments of aspartame’s health risks - especially the risks of prenatal and early postnatal exposures. We call upon food agencies to reassess Acceptable Daily Intake (ADI) levels for aspartame. We note that an Advisory Group to the International Agency for Research on Cancer has recommended high-priority reevaluation of aspartame’s carcinogenicity to humans.

How fragmentation can undermine the public health response to Covid-19

Responses to COVID-19 have largely been led by local, national, and international public health agencies, who have activated their pandemic plans and opened the epidemiological toolkit of modelling, testing, isolation and movement restrictions, surveillance, and contact tracing. In the contemporary tech-heavy world, many assumed that the common manual process of human investigators and phone calls could or should be replaced by digital solutions. But it's not as simple as "add more technology" - the complex way in which users and societies interact with the technology has significant impacts on effectiveness. When efforts are not well co-ordinated, fragmentation in system design and user experience can negatively impact the public health response. This article briefly covers the journey of how contact tracing registers and digital diaries evolved in New Zealand during the COVID-19 pandemic, the initial poor outcomes caused by the lack of central co-ordination, and the later improvement.

Systematic review in evidence-based risk assessment.

Systematic reviews provide a structured framework for summarizing the available evidence in a comprehensive, objective, and transparent manner. They inform evidence-based guidelines in medicine, public policy, and more recently, in environmental health and toxicology. Many regulatory agencies have extended and adapted the well-established systematic review methods, initially developed for clinical studies, for their assessment needs. The use of systematic reviews to summarize evidence from existing human, animal, and mechanistic studies can reduce reliance on animal test data in risk assessment and can help avoid unnecessary duplication of animal experiments that have already been conducted. As alternative test methods can be expected to play an increasing role in human health risk assessment in the future, systematic reviews can be particularly helpful in validating these alternatives. The field of evidence-based toxicology has undergone extensive development since its first meeting in 2007 as a result of collaborative efforts among international experts and public health agencies, particularly with respect to the use of mechanistic data and evidence integration. The continued development and wider adoption of systematic review methodology can lead to better 3R implementation. As undertaking a systematic review can be a complex and lengthy process, it is important to understand the main steps involved. Key steps, along with current best practices, are described with references to guidance from organizations with expertise in evidence synthesis. Applications of systematic reviews in clinical, observational, and experimental studies are presented. Finally, software tools available to facilitate and increase the efficiency of completing a systematic review are described.

Influenza vaccination strategies for 2020-21 in the context of COVID-19.

BackgroundInfluenza vaccination prevents people from influenza-related diseases and thereby mitigates the burden on national health systems when COVID-19 circulates and public health measures controlling respiratory viral infections are relaxed. However, it is challenging to maintain influenza vaccine services as the COVID-19 pandemic has the potential to disrupt vaccination programmes in many countries during the 2020/21 winter. We summarise available recommendations and strategies on influenza vaccination, specifically the changes in the context of the COVID-19 pandemic.MethodsWe searched websites and databases of national and international public health agencies (focusing on Europe, North and South America, Australia, New Zealand, and South Africa). We also contacted key influenza immunization focal points and experts in respective countries and organizations including WHO and ECDC.ResultsAvailable global and regional guidance emphasises the control of COVID-19 infection in immunisation settings by implementing multiple measures, such as physical distancing, hand hygiene practice, appropriate use of personal protective equipment by health care workers and establishing separate vaccination sessions for medically vulnerable people. The guidance also emphasises using alternative models or settings (eg, outdoor areas and pharmacies) for vaccine delivery, communication strategies and developing registry and catch-up programmes to achieve high coverage. Several novel national strategies have been adopted, such as combining influenza vaccination with other medical visits and setting up outdoor and drive through vaccination clinics. Several Southern Hemisphere countries have increased influenza vaccine coverage substantially for the 2020 influenza season. Most of the countries included in our review have planned a universal or near universal influenza vaccination for health care workers, or have made influenza vaccination for health care workers mandatory. Australia has requested that all workers and visitors in long term care facilities receive influenza vaccine. The UK has planned to expand the influenza programme to provide free influenza vaccine for the first time to all adults 50-64 years of age, people on the shielded patient list and their household members and children in the first year of secondary school. South Africa has additionally prioritised people with hypertension for influenza vaccination.ConclusionsThis review of influenza vaccination guidance and strategies should support strategy development on influenza vaccination in the context of COVID-19.

Efficacy and Use of Cloth Masks: A Scoping Review.

During the coronavirus disease 2019 (COVID-19) pandemic, there has been a global shortage of personal protective equipment (PPE). In this setting, cloth masks may play an important role in limiting disease transmission; however, current literature on the use of cloth masks remains inconclusive. This review aims to integrate current studies and guidelines to determine the efficacy and use of cloth masks in healthcare settings and/or the community. Evidence-based suggestions on the most effective use of cloth masks during a pandemic are presented.Embase, MEDLINE, and Google Scholar were searched on March 31, 2020, and updated on April 6, 2020. Studies reporting on the efficacy, usability, and accessibility of cloth masks were included. Additionally, a search of guidelines and recommendations on cloth mask usage was conducted through published material by international and national public health agencies.Nine articles were included in this review after full-text screening. The clinical efficacy of a face mask is determined by the filtration efficacy of the material, fit of the mask, and compliance to wearing the mask. Household fabrics such as cotton T-shirts and towels have some filtration efficacy and therefore potential for droplet retention and protection against virus-containing particles. However, the percentage of penetration in cloth masks is higher than surgical masks or N95 respirators.Cloth masks have limited inward protection in healthcare settings where viral exposure is high but may be beneficial for outward protection in low-risk settings and use by the general public where no other alternatives to medical masks are available.

The role of Force Health Protection in the Canadian Armed Forces' response to the COVID-19 pandemic.

Within the Canadian Armed Forces (CAF), public health is managed by the Directorate of Force Health Protection (DFHP), a branch of the Canadian Forces Health Services Group. Since the emergence of the novel coronavirus (SARS-CoV-19), DFHP has become heavily involved in health surveillance, outbreak monitoring, policy development, providing evidence-based guidance and advice, liaising with other national, provincial and territorial, municipal and international public health agencies, and ensuring environmental safety of CAF members. Some specific activities include supporting operations and deployments, amending policies and training and promoting hand hygiene, physical distancing and personal protective equipment use. In addition to taking measures to protect its members, CAF-Department of National Defence has contributed to Canada's national response to coronavirus disease 2019 (COVID-19). The DFHP will be developing training for allied health professionals to assist with contact tracing and follow-up, and will ensure adequate resources are in place to manage surge capacity for COVID-19. With these ongoing efforts, initiatives and lessons learned, DFHP is well placed to carry on with its mandate to protect and promote the health and well-being of CAF members and National Defence civilian employees, assisting Canadians and ensuring that CAF members are ready to serve their missions at home and abroad.

COVID-19 Pandemic – Implications, Planning, and Recommendations related to Dental Care Services and Dental Education

During the past few months, our understanding of the transmission, epidemiology, clinical symptoms, and management of Covid-19 has considerably improved. This had made the dental healthcare personnel confident enough and ready to provide safely by implementing efficient prevention and cross-infection control strategies in the dental clinical setting. , At the same time, it is necessary that we must be constantly aware of the continuation of such infectious threats challenging our infection control regimen and preparedness to provide dental treatments and teaching and education. Good infection prevention and control strategies need to be evidence-based and in line with the recommendations of the local and international public health agencies. The disruption in dental services and dental education all over the world resulted in this pandemic has emphasized and resulted in new, innovative and improved infection prevention and control strategies and adoption of alternative teaching, learning and assessment strategies for students. It further reinforces the need for continued research exploring ways for responding better to future contagious disease threats.&#x0D;

Evolving global and national criteria for identifying a suspected case of COVID-19.

BackgroundThe outbreak of coronavirus disease 2019 (COVID-19) began in December 2019 and continues to spread worldwide. Rapid and accurate identification of suspected cases is critical in slowing spread of the virus that causes the disease. We aimed to highlight discrepancies in the various criteria used by international agencies and highly impacted individual countries around the world.MethodsWe reviewed the criteria for identifying a suspected case of COVID-19 used by two international public health agencies and 10 countries across Asia, Europe, and North America. The criteria included information on the clinical causes of illness and epidemiological risk factors. Non-English language guidelines were translated into English by a co-author who is fluent in that particular language.ResultsAlthough most criteria are modifications of World Health Organization recommendations, the specific clinical features and epidemiological risks for triggering evaluation of patients with suspected COVID-19 differed widely among countries. The rationale for these differences may be related to each country’s resources, politics, experience with previous outbreaks or pandemics, health insurance system, COVID-19 outbreak severity, and other undetermined factors.ConclusionWe found no consensus regarding the best diagnostic criteria for identifying a suspected case of COVID-19.

A Brief History of Ebolavirus Disease: Paving the Way Forward by Learning from the Previous Outbreaks.

In this review, Ebolavirus Disease (EVD) outbreaks have been comprehensively reviewed from their beginning until now. It chronologically discusses how each outbreak was tackled, national and international actions taken, diagnostic methods applied, the infection control procedures put in place, and the lessons learnt from each epidemic for the control of subsequent epidemics. Data for this review were obtained from literature published between 1967 and 2016 in key medical databases, the official websites of various governmental organisations, international public health agencies, and regulatory bodies. Despite major developments in the field of EVD, there has been little progress in its specific therapy or prevention. Historically, individuals who recovered from EVD acted as a source of fresh frozen plasma (containing IgG) that has been used to treat other acutely ill patients, however this therapeutic modality has limitations due to the risk of transmission of blood-borne infections. With the use of advanced and efficient purification methods the incidence of unwanted side effects following immune serum therapy has currently been greatly reduced. Creation of a safe plasma pool that covers immunoglobulins against all strains of EVD is now a research priority. Recommendations on how future EVD outbreaks can be better managed have been discussed.

Potential global pandemics: the role of the WHO and other public health bodies.

In light of the emergence of the new coronavirus in China, Emeritus Professor Alan Glasper, from the University of Southampton, discusses the response strategies adopted by international and national public health agencies.

Enrichment post-library preparation enhances the sensitivity of high-throughput sequencing-based detection and characterization of viruses from complex samples

BackgroundSequencing-based detection and characterization of viruses in complex samples can suffer from lack of sensitivity due to a variety of factors including, but not limited to, low titer, small genome size, and contribution of host or environmental nucleic acids. Hybridization-based target enrichment is one potential method for increasing the sensitivity of viral detection via high-throughput sequencing.ResultsThis study expands upon two previously developed panels of virus enrichment probes (for filoviruses and for respiratory viruses) to include other viruses of biodefense and/or biosurveillance concern to the U.S. Department of Defense and various international public health agencies. The newly expanded and combined panel is tested using carefully constructed synthetic metagenomic samples that contain clinically relevant amounts of viral genetic material. Target enrichment results in a dramatic increase in sensitivity for virus detection as compared to shotgun sequencing, yielding full, deeply covered viral genomes from materials with Ct values suggesting that amplicon sequencing would be likely to fail. Increased pooling to improve cost- and time-effectiveness does not negatively affect the ability to obtain full-length viral genomes, even in the case of co-infections, although as expected, it does decrease depth of coverage.ConclusionsHybridization-based target enrichment is an effective solution to obtain full-length viral genomes for samples from which virus detection would fail via unbiased, shotgun sequencing or even via amplicon sequencing. As the development and testing of probe sets for viral target enrichment expands and continues, the application of this technique, in conjunction with deeper pooling strategies, could make high-throughput sequencing more economical for routine use in biosurveillance, biodefense and outbreak investigations.

Genomic Analysis of Lassa Virus during an Increase in Cases in Nigeria in 2018

SummaryDuring 2018, an unusual increase in Lassa fever cases occurred in Nigeria, raising concern among national and international public health agencies. We analyzed 220 Lassa virus genomes from infected patients, including 129 from the 2017–2018 transmission season, to understand the viral populations underpinning the increase. A total of 14 initial genomes from 2018 samples were generated at Redeemer’s University in Nigeria, and the findings were shared with the Nigerian Center for Disease Control in real time. We found that the increase in cases was not attributable to a particular Lassa virus strain or sustained by human-to-human transmission. Instead, the data were consistent with ongoing cross-species transmission from local rodent populations. Phylogenetic analysis also revealed extensive viral diversity that was structured according to geography, with major rivers appearing to act as barriers to migration of the rodent reservoir.