Mystery of love, goiter and death in flu pandemic

Ivan Mestrovic (1883-1962), a Croatian sculptor and architect, portrayed his close friend Marija Banac (born Racic) with a goiter. She died from flu in 1918 in Rome, just few days apart from her brother Edi Racic and his fiancée. In the tragic memory of the Racic family that disappeared in the burst of a terrible pandemic, Mestrovic built a church and mausoleum in Cavtat near Dubrovnik.

Deciphering transmission dynamics and spillover of avian influenza viruses from avian species to swine populations globally

Genome sequences of eleven avian influenza virus (AIV) subtypes have been reported in swine populations from seven countries until August 2020. To unravel the transmission dynamics and spillover events of AIVs from avian reservoirs to swine, full-length hemagglutinin (HA) sequences of AIV subtypes (n = 11) reported from various avian species and swine were retrieved from the ‘Influenza Research Database’. Phylogenetic analysis identified closely related avian and swine AIV sequences suggesting potential spillover events from multiple domestic and wild avian species, including chicken, duck, pigeon, goose, quail, and aquatic birds to swine. Furthermore, N-linked glycosylation analysis of these closely related AIV sequences supported the possibility of multiple spillover events of highly pathogenic H5N1 and low pathogenic H9N2 viruses from various avian species to swine. The principal coordinate analysis further validated these findings for H5N1 and H9N2 viruses; however, spillover events of the other nine AIV subtypes were limited. Interestingly, the presence of potential mammalian adaptation markers, particularly in some of the swine H5N1, H7N9, and H9N2 viruses, suggested that these viruses may have already adapted in swine. The occurrence and circulation of these AIVs in swine, especially the H5N1 and H9N2 viruses with numerous spillover events from the avian reservoirs to swine, pose a significant threat in terms of their reassortment with endemic swine viruses or circulating human influenza viruses within the swine which may facilitate the emergence of a novel influenza virus strain with pandemic potential.

Partially RepRapable automated open source bag valve mask-based ventilator

This study describes the development of a simple and easy-to-build portable automated bag valve mask (BVM) compression system, which, during acute shortages and supply chain disruptions can serve as a temporary emergency ventilator. The resuscitation system is based on the Arduino controller with a real-time operating system installed on a largely RepRap 3-D printable parametric component-based structure. The cost of the materials for the system is under $170, which makes it affordable for replication by makers around the world. The device provides a controlled breathing mode with tidal volumes from 100 to 800 mL, breathing rates from 5 to 40 breaths/minute, and inspiratory-to-expiratory ratio from 1:1 to 1:4. The system is designed for reliability and scalability of measurement circuits through the use of the serial peripheral interface and has the ability to connect additional hardware due to the object-oriented algorithmic approach. Experimental results after testing on an artificial lung for peak inspiratory pressure (PIP), respiratory rate (RR), positive end-expiratory pressure (PEEP), tidal volume, proximal pressure, and lung pressure demonstrate repeatability and accuracy exceeding human capabilities in BVM-based manual ventilation. Future work is necessary to further develop and test the system to make it acceptable for deployment outside of emergencies such as with COVID-19 pandemic in clinical environments, however, the nature of the design is such that desired features are relatively easy to add using protocols and parametric design files provided.

Partially RepRapable automated open source bag valve mask-based ventilator

This study describes the development of a simple and easy-to-build portable automated bag valve mask (BVM) compression system, which, during acute shortages and supply chain disruptions can serve as a temporary emergency ventilator. The resuscitation system is based on the Arduino controller with a real-time operating system installed on a largely RepRap 3-D printable parametric component-based structure. The cost of the materials for the system is under $170, which makes it affordable for replication by makers around the world. The device provides a controlled breathing mode with tidal volumes from 100 to 800 mL, breathing rates from 5 to 40 breaths/minute, and inspiratory-to-expiratory ratio from 1:1 to 1:4. The system is designed for reliability and scalability of measurement circuits through the use of the serial peripheral interface and has the ability to connect additional hardware due to the object-oriented algorithmic approach. Experimental results after testing on an artificial lung for peak inspiratory pressure (PIP), respiratory rate (RR), positive end-expiratory pressure (PEEP), tidal volume, proximal pressure, and lung pressure demonstrate repeatability and accuracy exceeding human capabilities in BVM-based manual ventilation. Future work is necessary to further develop and test the system to make it acceptable for deployment outside of emergencies such as with COVID-19 pandemic in clinical environments, however, the nature of the design is such that desired features are relatively easy to add using protocols and parametric design files provided.

Exploring the role of mass immunisation in influenza pandemic preparedness: A modelling study for the UK context

The nature and timing of the next influenza pandemic is unknown. This makes it difficult for policy makers to assess whether spending money now to prepare for mass immunisation in the event of a pandemic is worthwhile. We used simple epidemiological modelling and health economic analysis to identify the range of pandemic and policy scenarios under which plans to immunise the general UK population would have net benefit if a stockpiled vaccine or, alternatively, a responsively purchased vaccine were used. Each scenario we studied comprised a combination of pandemic, vaccine and immunisation programme characteristics in presence or absence of access to effective antivirals, with the chance of there being a pandemic each year fixed. Monetarised health benefits and cost savings from any influenza cases averted were set against the option, purchase, storage, distribution, administration, and disposal costs relevant for each scenario to give a discounted net present value over 10 years for planning to immunise, accounting for the possibility that there may be no pandemic over the period considered. To support understanding and exploration of model output, an interactive visualisation tool was devised and made available online. We evaluated over 29 million combinations of pandemic and policy characteristics. Preparedness plans incorporating mass immunisation show positive net present value for a wide range of scenarios, predominantly in the absence of effective antivirals. Plans based on the responsive purchase of vaccine have wider benefit than plans reliant on the purchase and maintenance of a stockpile if immunisation can start without extensive delays. This finding is not dependent on responsively purchased vaccine being more effective than stockpiled vaccine, but rather is driven by avoiding the costs of storing and replenishing a stockpile.

[History of influenza pandemics in China during the past century]

Five influenza pandemics had occurred during the past century (1918 "Spanish flu" , 1957 "Asian flu" , 1968 "Hong Kong flu" , 1977 "Russian flu" and 2009 H1N1 Pandemic), accounting for hundreds of millions of people infected and tens of millions dead. China was influenced by all the five pandemics, and three of them (1957 "Asian flu" , 1968 "Hong Kong flu" and 1977 "Russian flu" ) were originated from China. The pandemics triggered the establishment of public health agencies and influenza surveillance capacities. In addition, more resources were allocated to influenza-related research, prevention and control. As a leader in the field of influenza, China should further strengthen its pandemic preparedness and response to contribute to global health.

[An overview on the history of global influenza pandemics]

During the past 100 years, there had been four global pandemics on influenza that had greatly influenced the health and life of the people. This article summarized the features, experiences and lessons learned on these four influenza pandemics so as to prepare related measures targeting the possible pandemics/epidemics in the foreseeable future, in China.

[A review on the preparedness plans on influenza pandemics, by WHO and China: the current status and development]

Every influenza pandemic in history would end up with disastrous outcomes on mankind, of which the most notorious one was the "Spanish flu" pandemic in 1918. In the past century, with advanced knowledge on influenza viruses, laboratory technologies and surveillance methods, human beings were not as helpless when facing the influenza pandemic. In order to control the outbreaks and reducing the negative impacts, programs as: setting up and improving the influenza pandemic preparedness and response plan were recognized as important issues on early detection or prompt warning of any influenza virus strain that might lead to potential pandemics. The scheduled and planned control measures towards the pandemic preparedness and response plan had been considered of key importance in mitigating the peak of pandemic or controlling the transmission of virus. Since the "1918 influenza pandemic" , we had reviewed the evolution and development of plans regarding the preparedness and response on influenza pandemic issued by both WHO and China. We also emphasized on the variety of strategies which were linked to the preparedness and response at different historical stages, to provide reference for the pandemic preparedness of the disease, in the future.

Canadian Pandemic Influenza Preparedness: Communications strategy

When faced with uncertainty and unpredictability, early and transparent communication during a pandemic is critical to build trust and to ensure the credibility of public health advice. The responsibility for communicating with Canadians during a pandemic is shared by federal, provincial, territorial and local governments. A common plan is needed to ensure consistent, coordinated and appropriate communication. Canada's diversity in terms of its size, geography, languages and culture also requires a multifaceted approach so that the right message is delivered at the right time to the right person in the right format. The Communications and Stakeholder Liaison Annex is a recently updated communication strategy in the Canadian Pandemic Influenza Preparedness: Planning Guidance for the Health Sector (CPIP). The Annex emphasizes the importance of communicating with both the public and key stakeholders (e.g., health care providers, professional organizations and policymakers) before, during and after a pandemic. This strategy is grounded in several communications guiding principles: putting the health of Canadians first; providing timely and sound information; communicating in a coordinated fashion from across all levels of government; protecting confidentiality; and monitoring and adapting to the public's perception of risk. The Annex outlines a risk communications approach, proposes triggers for action based on pandemics of varying impact, and includes a Communication Protocol that will be used countrywide in the event of a pandemic.

Approximate Bayesian algorithm to estimate the basic reproduction number in an influenza pandemic using arrival times of imported cases

BACKGROUND

In an influenza pandemic, arrival times of cases are a proxy of the epidemic size and disease transmissibility. Because of intense surveillance of travelers from infected countries, detection is more rapid and complete than on local surveillance. Travel information can provide a more reliable estimation of transmission parameters.

METHOD

We developed an Approximate Bayesian Computation algorithm to estimate the basic reproduction number (R₀) in addition to the reporting rate and unobserved epidemic start time, utilizing travel, and routine surveillance data in an influenza pandemic. A simulation was conducted to assess the sampling uncertainty. The estimation approach was further applied to the 2009 influenza A/H1N1 pandemic in Mexico as a case study.

RESULTS

In the simulations, we showed that the estimation approach was valid and reliable in different simulation settings. We also found estimates of R₀ and the reporting rate to be 1.37 (95% Credible Interval [CI]: 1.26-1.42) and 4.9% (95% CI: 0.1%-18%), respectively, in the 2009 influenza pandemic in Mexico, which were robust to variations in the fixed parameters. The estimated R₀ was consistent with that in the literature.

CONCLUSIONS

This method is useful for officials to obtain reliable estimates of disease transmissibility for strategic planning. We suggest that improvements to the flow of reporting for confirmed cases among patients arriving at different countries are required.

We could learn much more from 1918 pandemic-the (mis)fortune of research relying on original death certificates

PURPOSE

The analysis of historical death certificates has enormous potential for understanding how the health of populations was shaped by diseases and epidemics and by the implementation of specific interventions. In Brazil, the systematic archiving of mortality records was initiated only in 1944-hence the analysis of death registers before this time requires searching for these documents in public archives, notaries, parishes, and especially ancient cemeteries, which are often the only remaining source of information about these deaths. This article describes an effort to locate original death certificates in Brazil and document their organization, accessibility, and preservation.

METHODS

To this end, we conducted an exploratory study in 19 of the 27 Brazilian states, focusing on the period surrounding the 1918 influenza pandemic (1913-1921). We included 55 cemeteries, 22 civil archives, and one military archive.

RESULTS

Apart from few exceptions, the results show the absence of a curatorial policy for the organization, access or even physical preservation of this material, frequently leading to unavailability, deterioration, and ultimately its complete loss.

CONCLUSIONS

This study indicates the need to promote the preservation of a historical heritage that is a key to understanding historical epidemiological patterns and human responses to global health threats.

Excess mortality patterns during 1918-1921 influenza pandemic in the state of Arizona, USA

PURPOSE

Our understanding of the temporal dynamics and age-specific mortality patterns of the 1918-1921 influenza pandemic remains scarce due to lack of detailed respiratory mortality datasets in the United States and abroad.

METHODS

We manually retrieved individual death records from Arizona during 1915-1921 and applied time series models to estimate the age specific mortality burden of the 1918-1921 influenza pandemic. We estimated influenza-related excess mortality rates and mortality rate ratio increase over baseline based on pneumonia and influenza (P&I), respiratory, tuberculosis and all-cause death categories.

RESULTS

Based on our analysis of 35,151 individual mortality records from Arizona, we identified three successive pandemic waves in spring 1918, fall 1918-winter 1919 and winter 1920. The pandemic associated excess mortality rates per 10,000 population in Arizona was estimated at 83 for P&I, 86 for respiratory causes, 84 for all-causes and 9 for tuberculosis. Age-specific P&I and tuberculosis excess death rates were highest among 25- to 44-year-olds and individuals ≥65 years, respectively. The 25- to 44-year-olds and 5- to 14-year-olds had highest P&I and tuberculosis mortality impact respectively when considering the ratio over background mortality.

CONCLUSIONS

The 1918-1921 influenza pandemic killed an estimated 0.8% of the Arizona population in three closely spaced consecutive waves. The mortality impact of the fall 1918 wave in Arizona lies in the upper range of previous estimates reported for other US settings and Europe, with a telltale age distribution of deaths concentrated among young adults. We identified a significant rise in tuberculosis-related mortality during the pandemic, lending support to the hypothesis that tuberculosis was a risk factor for severe pandemic infection. Our findings add to our current understanding of the mortality impact of this pandemic in the US and globally.

A statistical method utilizing information of imported cases to estimate the transmissibility for an influenza pandemic

Background

In a new influenza pandemic, travel data such as arrival times of cases seeded by the originating country can be regarded as a combination of the epidemic size and the mobility networks of infections connecting the originating country with other regions. It can be a complete and timely source for estimating the basic reproduction number (R₀), a key indicator of disease transmissibility.

Method

In this study, we developed a likelihood-based method using arrival times of infected cases in different countries to estimate R₀ for influenza pandemics. A simulation was conducted to assess the performance of the proposed method. We further applied the method to the outbreak of the influenza pandemic A/H1N1 in Mexico.

Results

In the numerical application, the estimated R₀ was equal to 1.69 with a 95% confidence interval (1.65, 1.73). For the simulation results, the estimations were robust to the decline of travel rate and other parameter assumptions. Nevertheless, the estimates were moderately sensitive to the assumption of infectious duration. Generally, the findings were in line with other relevant studies.

Conclusions

Our approach as well as the estimate is potential to assist officials in planning control and prevention measures. Improved coordination to streamline or even centralize surveillance of imported cases among countries will thus be beneficial to public health.

The coexistence or replacement of two subtypes of influenza

A pandemic subtype of influenza A sometimes replaces but sometimes coexists with the previous seasonal subtype. For example, the 1957 pandemic subtype H2N2 replaced the seasonal subtype H1N1; whereas after 1977 subtypes H1N1 (from the pandemic) and H3N2 continue to coexist. In an attempt to understand these alternatives, a hybrid model for the dynamics of influenza A is formulated. During an epidemic season the model takes into account cross-immunity of strains depending on the most recent seasonal infection. This cross-immunity reduces susceptibility to related strains of the seasonal subtype, and wanes with time due to virus drift. The population is assumed to reach an equilibrium distribution in susceptibility after several seasons, and then a pandemic subtype appears. Individuals who have been infected by the seasonal subtype all have the same cross-immunity to the pandemic subtype. A combination of theoretical and numerical analyses shows that for very strong cross-immunity between the subtypes the pandemic cannot invade, whereas for strong and weak cross-immunity there is coexistence for the season following the pandemic, and for intermediate levels of cross-immunity the pandemic may replace the seasonal subtype. This replacement depends on the basic reproduction numbers of seasonal and pandemic influenza. Vaccination against the seasonal subtype is found to slightly increase this range for pandemic replacement, with the range increasing with increasing vaccine protection and with the length of time that vaccine-induced immunity lasts.

How high is a high risk? Prioritising high-risk individuals in an influenza pandemic

Pandemic contingency plans frequently define priority groups that are given preferential access to influenza vaccine. One of the most commonly named groups for prioritisation is that of high-risk individuals. However, current models of categorisation are unsatisfactory in a number of ways. It will be argued that existing vaccination strategies fail to adequately define what kind of risks are being considered and how, as well as on the basis of which information, these risks are calculated. Moreover, it will be suggested that existing vaccination strategies fail to specify of what magnitude a risk has to be, in order to be categorised as 'high'. Finally, it shall be argued that a mere focus on the size of a risk factor may lead policy makers to overlook underlying concerns of distributive justice.

An estimate of the incidence of influenza-like illness during the influenza pandemic of 2009

INTRODUCTION

The influenza pandemic of 2009 had a great social impact. Many health resources were devoted to the care, prevention and surveillance of this disease. Epidemiological surveillance is based on the reporting of cases of influenza-like illness (ILI) and confirmed influenza cases. The objective was to estimate the true incidence of ILI during the influenza pandemic of 2009.

METHODS

The capture-recapture method was applied during the month of highest influenza incidence in Castellón. Two notification systems were used: (i)electronic reporting of Notifiable Diseases (ND), and (ii)laboratory-based (LAB) data collection. Estimates were made by stratifying by age group and week. Independence coefficients were calculated for those strata.

RESULTS

No dependence was found between stratification variables and the reporting system. A total of 7,181 ND cases and 524 LAB cases were identified, of which 211 were recorded in both systems. The estimated total of cases was 17,785 in a single month. In the study period, almost 4% of people in the area suffered flu symptoms (cumulative incidence), with 1% being affected each day (daily prevalence). The sensitivity of the ND system was 40%, i.e., the percentage of patients seeking primary care.

CONCLUSIONS

To obtain an estimate of the actual incidence of influenza-like illness in the population during a pandemic period, the number of medical consultations should be multiplied by a factor of 2.5. This factor is lower than that estimated for periods without pandemic alert.

Perceptions of emergency nurses during the human swine influenza outbreak: a qualitative study

INTRODUCTION

The primary aim of this study was to explore the perception of Hong Kong emergency nurses regarding their work during the human swine influenza pandemic outbreak.

METHODS

In this exploratory, qualitative study, 10 emergency nurses from a regional hospital in Hong Kong were recruited using purposive sampling. Semi-structured, face-to-face individual interviews were conducted. Qualitative content analysis was utilized to analyze the transcripts.

RESULTS

The three following categories emerged from the interview data: concerns about health, comments on the administration, and attitudes of professionalism. Nurses viewed the human swine influenza as a threat to their personal and families' health. However, nurses perceived that the severity of the disease was exaggerated by the public. Improvements in planning the circulation of information, allocation of manpower, and utilization of personal protective equipment were indicated. The emergency nurses demonstrated a sense of commitment and professional morale in promoting a high quality of nursing care.

DISCUSSION

Various factors affecting the perceptions of emergency nurses toward their professional duties during the influenza pandemic were identified. By understanding these perceptions, appropriate planning, policies, and guidelines can be formulated to meet the healthcare needs of patients during future pandemic outbreaks.

Experience of Triage During an A/H1N1 Influenza Pandemic in After-Hours Emergency Centers

During the 2009 A/H1N1 influenza pandemic in Sendai, two primary emergency clinics, which are after-hours emergency centers managed by the Sendai Emergency Medical Service Foundation, were inundated with many influenza patients. In the course of the pandemic, from August 1, 2009 to March 31, 2010, a total of 47,831 internal medicine and pediatric patients visited the two clinics and rapid influenza tests were performed in 17,167 of patients, in which 6,697 patients tested A-positive. Consequently, 10,743 patients were diagnosed with influenza, which included 1,447 patients that tested negative, and 2,599 patients that were not tested. Prior to the physicians check up, nurses performed triage and divided the patients into two groups, isolated and non-isolated. We examined the effect of triage, using the results of the rapid influenza test and antiviral drug administration, in each of the early, middle and maximum pandemic phases. Triage was considered effective in the early and middle phases, where the average number of influenza patients that visited the clinic per day were 21.4 and 50.6, respectively. But in the maximum phase where the average number of influenza patients soared to 275.3 per day, one out of three patients in the non-isolated group was clinically diagnosed as influenza. We were unable to separate influenza patients effectively in the maximum phase of pandemic.