Preparing for pandemic influenza: the need for enhanced surveillance

The ethical dilemmas of risky decisions

Even in a pandemic there seem to be inherent conflicts of interest between the individual and societal consequences of remedial actions and strategies. Actions taken in the sole interests of patients, as required by the Hippocratic oath, can have broadly inconvenient economic implications for the State. ("Average" benefits for a population can impose individual inconveniences for the vulnerable.). Understandably these decisions are not normally made explicitly and transparently by governments. This leads to seemingly illogical and inhumane strategies which are not understood and hence mistrusted and often ignored by the public. Vaccination sentiments on social media are often an unwanted symptom of this dilemma. This article outlines and discusses a number of examples of such situations with a focus on ethical aspects. It concludes that each case must be considered individually as to the issues that need to be weighed in these difficult decisions; and that there are no clear and universally acceptable ethical solutions. What can be learned from the COVID-19 crisis is that short term utilitarianism has consequences that in the eyes of the population are unacceptable. This lesson seems equally valid for cost benefit evaluations regarding other risks, such as from hazardous industries, flood defenses, and air transport. Decisionmakers and politicians can learn that persuasion only goes so far. In the end the people appear to prioritize in terms of deontology.

Framework for creating an incident command center during crises

The Hospital Incident Command System (HICS) is an incident management system specific to hospitals based on the principles of Incident Command System (ICS), and it includes prevention, protection, mitigation, response, and recovery. It plays a crucial role in effective and timely response during the periods of disasters, mass casualties, and public health emergencies. In recent times, hospitals have used a customized HICS structure to coordinate effective responses to public health problems such as the Ebola outbreak in the US and SARS epidemic in Taiwan.

The current COVID-19 pandemic has placed unprecedented challenges on the healthcare system, necessitating the creation of HICS that can help in the proper allocation of resources and ineffective utilization of healthcare personnel. The key elements in managing a response to this pandemic include screening and early diagnosis, quarantining affected individuals, monitoring disease progression, delivering appropriate treatment, and ensuring an adequate supply of personal protective equipment (PPE) to healthcare staff.

Influenza virus surveillance in Pakistan during 2008-2011

Background

There is little information about influenza among the Pakistani population. In order to assess the trends of Influenza-like-Illness (ILI) and to monitor the predominant circulating strains of influenza viruses, a country-wide lab-based surveillance system for ILI and Severe Acute Respiratory Illness (SARI) with weekly sampling and reporting was established in 2008. This system was necessary for early detection of emerging novel influenza subtypes and timely response for influenza prevention and control.

Methods

Five sentinel sites at tertiary care hospitals across Pakistan collected epidemiological data and respiratory samples from Influenza-like illness (ILI) and severe acute respiratory illness (SARI) cases from January 2008 to December 2011. Samples were typed and sub-typed by Real-Time RT-PCR assay.

Results

A total of 6258 specimens were analyzed; influenza virus was detected in 1489 (24%) samples, including 1066 (72%) Influenza type A and 423 (28%) influenza type B viruses. Amongst influenza A viruses, 25 (2%) were seasonal A/H1N1, 169 (16%) were A/H3N2 and 872 (82 %) were A(H1N1)pdm09. Influenza B virus circulation was detected throughout the year along with few cases of seasonal A/H1N1 virus during late winter and spring. Influenza A/H3N2 virus circulation was mainly observed during summer months (August-October).

Conclusions

The findings of this study emphasize the need for continuous and comprehensive influenza surveillance. Prospective data from multiple years is needed to predict seasonal trends for vaccine development and to further fortify pandemic preparedness.

Pandemic influenza planning, United States, 1978-2008

During the past century, 4 influenza pandemics occurred. After the emergence of a novel influenza virus of swine origin in 1976, national, state, and local US public health authorities began planning efforts to respond to future pandemics. Several events have since stimulated progress in public health emergency planning: the 1997 avian influenza A(H5N1) outbreak in Hong Kong, China; the 2001 anthrax attacks in the United States; the 2003 outbreak of severe acute respiratory syndrome; and the 2003 reemergence of influenza A(H5N1) virus infection in humans. We outline the evolution of US pandemic planning since the late 1970s, summarize planning accomplishments, and explain their ongoing importance. The public health community's response to the 2009 influenza A(H1N1)pdm09 pandemic demonstrated the value of planning and provided insights into improving future plans and response efforts. Preparedness planning will enhance the collective, multilevel response to future public health crises.

The securitisation of pandemic influenza: framing, security and public policy

This article examines how pandemic influenza has been framed as a security issue, threatening the functioning of both state and society, and the policy responses to this framing. Pandemic influenza has long been recognised as a threat to human health. Despite this, for much of the twentieth century it was not recognised as a security threat. In the decade surrounding the new millennium, however, the disease was successfully securitised with profound implications for public policy. This article addresses the construction of pandemic influenza as a threat. Drawing on the work of the Copenhagen School, it examines how it was successfully securitised at the turn of the millennium and with what consequences for public policy.

Rapid detection of pandemic influenza in the presence of seasonal influenza

BACKGROUND

Key to the control of pandemic influenza are surveillance systems that raise alarms rapidly and sensitively. In addition, they must minimise false alarms during a normal influenza season. We develop a method that uses historical syndromic influenza data from the existing surveillance system 'SERVIS' (Scottish Enhanced Respiratory Virus Infection Surveillance) for influenza-like illness (ILI) in Scotland.

METHODS

We develop an algorithm based on the weekly case ratio (WCR) of reported ILI cases to generate an alarm for pandemic influenza. From the seasonal influenza data from 13 Scottish health boards, we estimate the joint probability distribution of the country-level WCR and the number of health boards showing synchronous increases in reported influenza cases over the previous week. Pandemic cases are sampled with various case reporting rates from simulated pandemic influenza infections and overlaid with seasonal SERVIS data from 2001 to 2007. Using this combined time series we test our method for speed of detection, sensitivity and specificity. Also, the 2008-09 SERVIS ILI cases are used for testing detection performances of the three methods with a real pandemic data.

RESULTS

We compare our method, based on our simulation study, to the moving-average Cumulative Sums (Mov-Avg Cusum) and ILI rate threshold methods and find it to be more sensitive and rapid. For 1% case reporting and detection specificity of 95%, our method is 100% sensitive and has median detection time (MDT) of 4 weeks while the Mov-Avg Cusum and ILI rate threshold methods are, respectively, 97% and 100% sensitive with MDT of 5 weeks. At 99% specificity, our method remains 100% sensitive with MDT of 5 weeks. Although the threshold method maintains its sensitivity of 100% with MDT of 5 weeks, sensitivity of Mov-Avg Cusum declines to 92% with increased MDT of 6 weeks. For a two-fold decrease in the case reporting rate (0.5%) and 99% specificity, the WCR and threshold methods, respectively, have MDT of 5 and 6 weeks with both having sensitivity close to 100% while the Mov-Avg Cusum method can only manage sensitivity of 77% with MDT of 6 weeks. However, the WCR and Mov-Avg Cusum methods outperform the ILI threshold method by 1 week in retrospective detection of the 2009 pandemic in Scotland.

CONCLUSIONS

While computationally and statistically simple to implement, the WCR algorithm is capable of raising alarms, rapidly and sensitively, for influenza pandemics against a background of seasonal influenza. Although the algorithm was developed using the SERVIS data, it has the capacity to be used at other geographic scales and for different disease systems where buying some early extra time is critical.

Influenza pandemics: past, present and future challenges

Influenza epidemics occur regularly and prediction of their conversion to pandemics and their impact is difficult. Coordination of efforts on a global scale to control or reduce the impact is fraught with potential for under and overreaction. In light of the 1956 pandemic and more recently the SARS and H1N1 pandemics, the public health community took steps toward strengthening global surveillance and a coordinated response in keeping with the continuing memory of the tragedy seen in 1918. The scientific, professional, and technical resources of the 21st century are now advanced far beyond those then available. The H1N1 pandemic which commenced in 2009 progressed differently than predicted; its course was difficult to predict with any degree of certainty. Public responses to national immunization programs against the H1N1 virus have been weak. International movement of diseases can lead to creation of new endemic areas and continuous spread such as that which happened with West Nile Fever and Chikungunya. The lessons learned and the public and political responses to each actual or threatened pandemic will serve public health well in dealing with future challenges.

Pandemic influenza and community preparedness

OBJECTIVES

We aimed to examine community knowledge about and attitudes toward the threat of pandemic influenza and assess the community acceptability of strategies to reduce its effect.

METHODS

We conducted computer-aided telephone interviews in 2007 with a cross-sectional sample of rural and metropolitan residents of South Australia.

RESULTS

Of 1975 households interviewed, half (50.2%) had never heard of pandemic influenza or were unaware of its meaning. Only 10% of respondents were extremely concerned about the threat of pandemic influenza. Respondents identified children as the highest priority for vaccination, if supplies were limited; they ranked politicians and teachers as the lowest priority. Although only 61.7% of respondents agreed with a policy of home isolation, 98.2% agreed if it was part of a national strategy. Respondents considered television to be the best means of educating the community.

CONCLUSION

s. Community knowledge about pandemic influenza is poor despite widespread concern. Public education about pandemic influenza is essential if strategies to reduce the impact of the disease are to be effective.

Enhancement of influenza surveillance with aggregate rapid influenza test results: New Mexico, 2003-2007

OBJECTIVES

We sought to determine whether monitoring rapid influenza laboratory tests improved the influenza-like illness surveillance already in place in New Mexico.

METHODS

For the past 3 influenza seasons, the New Mexico Department of Health examined influenza-like illness visits and positive rapid influenza test results.

RESULTS

The proportion of positive rapid influenza test results started to rise earlier than did the percentage of clinical visits because of influenza-like illness in each of the past 3 influenza seasons: 5 weeks earlier during the 2004-2005 season; 3 weeks earlier in 2005-2006; and 2 weeks earlier in 2006-2007. In addition, rapid influenza tests showed a spike in influenza B activity late in the 2005-2006 season that influenza-like illness syndrome surveillance did not.

CONCLUSIONS

Laboratory-based rapid influenza test surveillance required relatively few resources to implement and offered a sensitive mechanism to detect the onset of influenza activity while allowing for the distinction of influenza types.

Strategies to improve global influenza surveillance: a decision tool for policymakers

BACKGROUND

Global pandemic influenza preparedness relies heavily on public health surveillance, but it is unclear that current surveillance fully meets pandemic preparedness needs.

METHODS

We first developed a conceptual framework to help systematically identify strategies to improve the detection of an early case or cluster of novel human influenza disease during the pre-pandemic period. We then developed a process model (flow diagram) depicting nine major pathways through which a case in the community could be detected and confirmed, and mapped the improvement strategies onto this model. Finally, we developed an interactive decision tool by building quantitative measures of probability and time into each step of the process model and programming it to calculate the net probability and time required for case detection through each detection pathway. Input values for each step can be varied by users to assess the effects of different improvement strategies, alone or in combination. We illustrate application of the tool using hypothetical input data reflecting baseline and 12-month follow-up scenarios, following concurrent implementation of multiple improvement strategies.

RESULTS

We compared outputs from the tool across detection pathways and across time, at baseline and 12-month follow up. The process model and outputs from the tool suggest that traditional efforts to build epidemiology and laboratory capacity are efficient strategies, as are more focused strategies within these, such as targeted laboratory testing; expedited specimen transport; use of technologies to streamline data flow; and improved reporting compliance. Other promising strategies stem from community detection - better harnessing of electronic data mining and establishment of community-based monitoring.

CONCLUSION

Our practical tool allows policymakers to use their own realistic baseline values and program projections to assess the relative impact of different interventions to improve the probability and timeliness of detecting early human cases or clusters caused by a novel influenza virus, a possible harbinger of a new pandemic. Policymakers can use results to target investments to improve their surveillance infrastructure. Multi-national planners can also use the tool to help guide directions in surveillance system improvements more globally. Finally, our systematic approach can also be tailored to help improve surveillance for other diseases.

Active influenza surveillance at the local level: a model for local health agencies

Laboratory-supported, community-based local surveillance systems for influenza can act as early warning systems in identifying the initial entry points of different influenza strains into the community. Unfortunately, local health departments often have limited resources to implement this type of surveillance. We developed and evaluated an active, local influenza surveillance system in 3 metropolitan Denver, Colo, counties that enabled timely case ascertainment and strain identification at little cost. When compared with Colorado's surveillance system, our system detected cases 7 to 8 weeks earlier than the state's electronic disease reporting system.

Avian influenza outbreak in Turkey through health personnel's views: a qualitative study

Background

Avian influenza threatens public health worldwide because it is usually associated with severe illness and, consequently, a higher risk of death. During the first months of 2006, Turkey experienced its first human avian influenza epidemic. A total of 21 human cases were identified, 12 of which were confirmed by the National Institute for Medical Research. Nine of the cases, including the four fatal ones, were from the Dogubeyazit-Van region. This study aims to evaluate the efforts at the avian influenza outbreak control in the Van-Dogubeyazit region in 2006 through the experiences of health personnel.

Methods

We conducted in-depth interviews with seventeen key informants who took active roles during the avian influenza outbreak in East Turkey during the first months of 2006. We gathered information about the initial responses, the progress and management of the outbreak control, and the reactions of the health professionals and the public. The findings of the study are reported according to the topics that appeared through thematic analysis of the interview transcripts.

Results

Following the first suspected avian influenza cases, a Van Crisis Coordination Committee was formed as the coordinating and decision-making body and played an important role in the appropriate timing of decisions. The health and agriculture services could not be well coordinated owing to the lack of integrated planning in preparation for outbreak and of integrated surveillance programs. Traditional poultry practice together with the low socio-economic status of the people and the lack of health care access in the region seemed to be a major risk for animal to animal and animal to human transmission. The strengths and weaknesses of the present health system – primary health care services, national surveillance and notification systems, human resource and management – affected the inter organizational coordination during the outbreak. Open communication between the government and the public played an important part in overcoming difficulties.

Conclusion

Although there were problems during the avian influenza outbreak in Turkey, the rapid responses of the central and regional health authorities and the performance of the health workers were the key points in controlling the epidemic. The lessons from this outbreak should provide an opportunity for integrating the preparation plans of the health and agricultural organizations, and for revising the surveillance system and enhancing the role of the primary health care services in controlling epidemic disease. Developing successful strategies based on knowledge and experience may play a valuable role in delaying an avian influenza pandemic.

The origin and virulence of the 1918 "Spanish" influenza virus

The "Spanish" influenza pandemic of 1918-19 caused acute illness in 25-30 percent of the world's population and resulted in the death of up to an estimated 40 million people. Using fixed and frozen lung tissue of 1918 influenza victims, the complete genomic sequence of the 1918 influenza virus has been deduced. Sequence and phylogenetic analysis of the completed 1918 influenza virus genes shows them to be the most avian-like among the mammalian-adapted viruses. This finding supports the hypotheses that (1) the pandemic virus contains genes derived from avian-like influenza virus strains and that (2) the 1918 virus is the common ancestor of human and classical swine H1N1 influenza viruses. The relationship of the 1918 virus with avian influenza viruses is further supported by recent work in which the 1918 hemagglutinin (HA) protein crystal structure was resolved. Neither the 1918 hemagglutinin (HA) nor the neuraminidase (NA) genes possess mutations known to increase tissue tropicity that account for the virulence of other influenza virus strains like A/WSN/33 or the highly pathogenic avian influenza H5 or H7 viruses. Using reverse genetics approaches, influenza virus constructs containing the 1918 HA and NA on a modern human influenza virus background were lethal in mice. The complete 1918 virus was even more virulent in mice. The genotypic basis of this virulence has not yet been elucidated. The complete sequence of the non-structural (NS) gene segment of the 1918 virus was deduced and also tested for the hypothesis that enhanced virulence in 1918 could have been due to type I interferon inhibition by the NS1 protein. Results from these experiments suggest that in human cells the 1918 NS1 is a very effective interferon antagonist, but the 1918 NS1 gene does not have the amino acid change that correlates with virulence in the H5N1 virus strains identified in 1997 in Hong Kong. Sequence analysis of the 1918 pandemic influenza virus is allowing us to test hypotheses as to the origin and virulence of this strain. This information should help elucidate how pandemic influenza virus strains emerge and what genetic features contribute to virulence in humans.

Whole-genome analysis of human influenza A virus reveals multiple persistent lineages and reassortment among recent H3N2 viruses

Understanding the evolution of influenza A viruses in humans is important for surveillance and vaccine strain selection. We performed a phylogenetic analysis of 156 complete genomes of human H3N2 influenza A viruses collected between 1999 and 2004 from New York State, United States, and observed multiple co-circulating clades with different population frequencies. Strikingly, phylogenies inferred for individual gene segments revealed that multiple reassortment events had occurred among these clades, such that one clade of H3N2 viruses present at least since 2000 had provided the hemagglutinin gene for all those H3N2 viruses sampled after the 2002–2003 influenza season. This reassortment event was the likely progenitor of the antigenically variant influenza strains that caused the A/Fujian/411/2002-like epidemic of the 2003–2004 influenza season. However, despite sharing the same hemagglutinin, these phylogenetically distinct lineages of viruses continue to co-circulate in the same population. These data, derived from the first large-scale analysis of H3N2 viruses, convincingly demonstrate that multiple lineages can co-circulate, persist, and reassort in epidemiologically significant ways, and underscore the importance of genomic analyses for future influenza surveillance.

Evolution of the flu virus is analyzed via genomic phylogeny; humans are found to provide a reservoir of antigenic variability implicit in flu adaptation and virulence.

Influenza a common viral infection among Hajj pilgrims: time for routine surveillance and vaccination

BACKGROUND

The annual Hajj pilgrimage to Mecca, Saudi Arabia brings over two million people to a small confined area. Respiratory tract infection is the most common disease transmitted during this period. For most of the etiologic agents of upper respiratory tract infections, no vaccine or prophylaxis is available, except for influenza. Yearly influenza vaccination of high-risk groups is recommended, but no special recommendations are available for those performing the Hajj or other similar large congregational activities. Viral surveillance studies are being carried out through more than 100 centers around the world to identify newly emerging viruses. Saudi Arabia is not one of those centers and no routine surveillance takes place.

METHODS

Five hundred Hajj pilgrims presenting with upper respiratory tract symptoms from different parts of the world were screened by way of a throat swab for viral culture, including influenza A and B, parainfluenza, respiratory syncytial virus (RSV), adenovirus, herpes simplex virus (HSV), and enteroviruses. Information was collected on age, sex, nationality, smoking habits and upper respiratory tract symptoms. Vaccination status for influenza and meningococcus was obtained by self-declaration, since most pilgrims did not have their vaccination cards with them. Only those with symptoms including at least fever, reported by the patient to be >38.3 degrees C, and/or sore throat were included. Pilgrims with any other symptoms, especially myalgia and fatigue alone, were excluded, since many of the physical chores during the pilgrimage may contribute to such symptoms.

RESULTS

Fifty-four patients (10.8%) had positive viral throat cultures. Of these, 27 (50%) were influenza B, 13 (24.1%) were HSV, 7 (12.9%) were RSV, 4 (7.4%) were parainfluenza, and 3 (5.6%) were influenza A. No enteroviruses or adenoviruses were detected, and no multiple infections were detected. Only 22 (4.7%) pilgrims received the influenza vaccine. When the results are applied to the total number of pilgrims in 2003, an estimate of 24,000 cases of influenza is obtained.

CONCLUSION

The findings from this study suggest a high incidence of influenza as a cause of upper respiratory tract infection among pilgrims, estimated to be 24,000 cases per Hajj season, excluding those becoming ill from contact with Hajj pilgrims returning home. They also indicate a very low vaccination rate for the influenza vaccine; as well as poor knowledge of its existence. Continued surveillance during the Hajj pilgrimage is necessary. The influenza vaccine should be a priority for those attending the Hajj pilgrimage, and should also be considered for antiviral prophylaxis.

The role of risk analysis in understanding bioterrorism

Recent events have made the domestic risk from bioterrorism more tangible. The risk management process so far, however, has not benefited from many of the contributions that analysts, communicators, and managers can make to the public discourse. Risk professionals can contribute much to the understanding of and solutions to bioterrorist events and threats. This article will provide an overview of the bioterrorism problem and outline a number of areas to which members of the Society for Risk Analysis, and other risk practitioners, could usefully contribute.

Enhancing public health surveillance for influenza virus by incorporating newly available rapid diagnostic tests

Beginning with the 1999-2000 influenza season, physicians throughout Hawaii ordering a viral culture for patients with suspected influenza were also offered influenza rapid testing. We compared the number of viral respiratory cultures sent to the Hawaii Department of Health and the number of providers who participated in influenza surveillance over consecutive influenza seasons. The number of viral respiratory cultures rose from 396 to 2,169 between the 1998-1999 and 2000-2001 influenza seasons, and the number of providers submitting >1 influenza culture increased from 34 to 327, respectively. The number of influenza isolates obtained each season also increased (from 64 to 491). The available data suggest that the changes observed in Hawaii's influenza surveillance were not secondary to differences in influenza activity between seasons. This is the first evaluation of integrating influenza rapid testing into public health surveillance. Coupling rapid tests with cultures appears to be an effective means of improving influenza surveillance.

The mercury concentration in saliva: correlation to number and extension of dental amalgam restorations

Beginning with the 1999-2000 influenza season, physicians throughout Hawaii ordering a viral culture for patients with suspected influenza were also offered influenza rapid testing. We compared the number of viral respiratory cultures sent to the Hawaii Department of Health and the number of providers who participated in influenza surveillance over consecutive influenza seasons. The number of viral respiratory cultures rose from 396 to 2,169 between the 1998-1999 and 2000-2001 influenza seasons, and the number of providers submitting >1 influenza culture increased from 34 to 327, respectively. The number of influenza isolates obtained each season also increased (from 64 to 491). The available data suggest that the changes observed in Hawaii’s influenza surveillance were not secondary to differences in influenza activity between seasons. This is the first evaluation of integrating influenza rapid testing into public health surveillance. Coupling rapid tests with cultures appears to be an effective means of improving influenza surveillance.

Integrating historical, clinical and molecular genetic data in order to explain the origin and virulence of the 1918 Spanish influenza virus

The Spanish influenza pandemic of 1918-1919 caused acute illness in 25-30% of the world's population and resulted in the death of 40 million people. The complete genomic sequence of the 1918 influenza virus will be deduced using fixed and frozen tissues of 1918 influenza victims. Sequence and phylogenetic analyses of the complete 1918 haemagglutinin (HA) and neuraminidase (NA) genes show them to be the most avian-like of mammalian sequences and support the hypothesis that the pandemic virus contained surface protein-encoding genes derived from an avian influenza strain and that the 1918 virus is very similar to the common ancestor of human and classical swine H1N1 influenza strains. Neither the 1918 HA genes nor the NA genes possessed mutations that are known to increase tissue tropicity, which accounts for the virulence of other influenza strains such as A/WSN/33 or fowl plague viruses. The complete sequence of the nonstructural (NS) gene segment of the 1918 virus was deduced and tested for the hypothesis that the enhanced virulence in 1918 could have been due to type I interferon inhibition by the NS1 protein. The results from these experiments were inconclusive. Sequence analysis of the 1918 pandemic influenza virus is allowing us to test hypotheses as to the origin and virulence of this strain. This information should help to elucidate how pandemic influenza strains emerge and what genetic features contribute to their virulence.