Doenças emergentes e condições de trabalho de enfermagem: um estudo de caso durante a pandemia de H1N1 no Rio de Janeiro

As doenças infecto-parasitárias, ainda hoje, em pleno século XXI são responsáveis por uma quantidade generosa de morbidade e mortalidade no Brasil e no mundo. Muitas delas são amplamente influenciadas pelas mudanças climáticas que estão ocorrendo em todo o planeta fazendo com que sua incidência e distribuição geográfica aumentem. A dengue é considerada a principal doença reemergente nos países tropicais e subtropicais. A malária tem forte incidência nos países ao sul do deserto do Saara na África, ocorrendo também em vários países da América do Sul que possuem parte da região Amazônica em seu território. Várias doenças voltam a assolar a população de vários locais como as leishmanioses, a Doença de Lyme, erlichioses entre outras. Em março de 2009 começam a ocorrer os primeiros casos de uma nova doença inicialmente denominada Influenza suína, a qual, levou alguns indivíduos a óbito em Oaxaca, uma cidade mexicana localizada a 400 quilômetros da capital. Rapidamente, a doença se espalhou pelo país e posteriormente, no começo do mês de abril de 2009 já, existiam relatos de casos em vários países. O objetivo geral desta pesquisa é verificar em que medida o cuidado de enfermagem realizado expressou um maior ou menor grau de controle do enfermeiro sobre seu trabalho, apontando para os potenciais riscos (biológicos) de adoecimento e impactos negativos na saúde deste trabalhador. O presente estudo foi desenvolvido por meio de uma abordagem quantitativa com desenho longitudinal e observacional, delineamento de pesquisa não experimental e caráter descritivo. Foi feita a análise observacional nas tendas quanto a sua infraestrutura e posteriormente foi passado um questionário aos enfermeiros pautado em questões sobre o risco biológico que estes estavam sendo submetidos. Faz-se necessário que a cultura do improviso acabe e comece a se pensar em uma nova realidade: as doenças transmissíveis são uma realidade, elas existem e há de ser feito um adequamento de tudo que esteja ligado à área de saúde pensando em um novo contexto. É imperioso que tanto as autoridades como os profissionais revejam e reflitam sobre o que aconteceu, para que os erros do passado possam ficar para trás e não se repitam.

Mutations in H5N1 influenza virus hemagglutinin that confer binding to human tracheal airway epithelium

The emergence in 2009 of a swine-origin H1N1 influenza virus as the first pandemic of the 21st Century is a timely reminder of the international public health impact of influenza viruses, even those associated with mild disease. The widespread distribution of highly pathogenic H5N1 influenza virus in the avian population has spawned concern that it may give rise to a human influenza pandemic. The mortality rate associated with occasional human infection by H5N1 virus approximates 60%, suggesting that an H5N1 pandemic would be devastating to global health and economy. To date, the H5N1 virus has not acquired the propensity to transmit efficiently between humans. The reasons behind this are unclear, especially given the high mutation rate associated with influenza virus replication. Here we used a panel of recombinant H5 hemagglutinin (HA) variants to demonstrate the potential for H5 HA to bind human airway epithelium, the predominant target tissue for influenza virus infection and spread. While parental H5 HA exhibited limited binding to human tracheal epithelium, introduction of selected mutations converted the binding profile to that of a current human influenza strain HA. Strikingly, these amino-acid changes required multiple simultaneous mutations in the genomes of naturally occurring H5 isolates. Moreover, H5 HAs bearing intermediate sequences failed to bind airway tissues and likely represent mutations that are an evolutionary "dead end." We conclude that, although genetic changes that adapt H5 to human airways can be demonstrated, they may not readily arise during natural virus replication. This genetic barrier limits the likelihood that current H5 viruses will originate a human pandemic.

Generation of candidate human influenza vaccine strains in cell culture: rehearsing the European response to an H7N1 pandemic threat

Background: Although H5N1 avian influenza viruses pose the most obvious imminent pandemic threat, there have been several recent zoonotic incidents involving transmission of H7 viruses to humans. Vaccines are the primary public health defense against pandemics, but reliance on embryonated chickens eggs to propagate vaccine and logistic problems posed by the use of new technology may slow our ability to respond rapidly in a pandemic situation. Objectives: We sought to generate an H7 candidate vaccine virus suitable for administration to humans whose generation and amplification avoided the use of eggs. Methods: We generated a suitable H7 vaccine virus by reverse genetics. This virus, known as RD3, comprises the internal genes of A/Puerto Rico/8/34 with surface antigens of the highly pathogenic avian strain A/Chicken/Italy/13474/99 (H7N1). The multi-basic amino acid site in the HA gene, associated with high pathogenicity in chickens, was removed. Results: The HA modification did not alter the antigenicity of the virus and the resultant single basic motif was stably retained following several passages in Vero and PER. C6 cells. RD3 was attenuated for growth in embryonated eggs, chickens, and ferrets. RD3 induced an antibody response in infected animals reactive against both the homologous virus and other H7 influenza viruses associated with recent infection by H7 viruses in humans. Conclusions: This is the first report of a candidate H7 vaccine virus for use in humans generated by reverse genetics and propagated entirely in mammalian tissue culture. The vaccine has potential use against a wide range of H7 strains.

A single amino acid in the HA of pH1N1 2009 influenza virus affects cell tropism in human airway epithelium, but not transmission in ferrets

The first pandemic of the 21(st) century, pandemic H1N1 2009 (pH1N1 2009), emerged from a swine-origin source. Although human infections with swine-origin influenza have been reported previously, none went on to cause a pandemic or indeed any sustained human transmission. In previous pandemics, specific residues in the receptor binding site of the haemagglutinin (HA) protein of influenza have been associated with the ability of the virus to transmit between humans. In the present study we investigated the effect of residue 227 in HA on cell tropism and transmission of pH1N1 2009. In pH1N1 2009 and recent seasonal H1N1 viruses this residue is glutamic acid, whereas in swine influenza it is alanine. Using human airway epithelium, we show a differential cell tropism of pH1N1 2009 compared to pH1N1 2009 E227A and swine influenza suggesting this residue may alter the sialic acid conformer binding preference of the HA. Furthermore, both pH1N1 2009 E227A and swine influenza multi-cycle viral growth was found to be attenuated in comparison to pH1N1 2009 in human airway epithelium. However this altered tropism and viral growth in human airway epithelium did not abrogate respiratory droplet transmission of pH1N1 2009 E227A in ferrets. Thus, acquisition of E at residue 227 was not solely responsible for the ability of pH1N1 2009 to transmit between humans.

Receptor binding profiles of avian influenza virus hemagglutinin subtypes on human cells as a predictor of pandemic potential

The host adaptation of influenza virus is partly dependent on the sialic acid (SA) isoform bound by the viral hemagglutinin (HA). Avian influenza viruses preferentially bind the α-2,3 SA and human influenza viruses the α-2,6 isoform. Each isoform is predominantly associated with different surface epithelial cell types of the human upper airway. Using recombinant HAs and human tracheal airway epithelial cells in vitro and ex vivo, we show that many avian HA subtypes do not adhere to this canonical view of SA specificity. The propensity of avian viruses to adapt to human receptors may thus be more widespread than previously supposed.

Knowledge and attitudes of health care workers from intensive care units regarding nosocomial transmission of influenza: a study on the immediate pre-pandemic period

The transmission of influenza in health care settings is a major threat to patients, especially those with severe diseases. The attitude of health care workers (HCWs) may influence the transmission of countless infections. The current study aimed to quantify knowledge and identify attitudes of HCWs involved in intensive care units (ICUs) regarding the risk of nosocomial influenza transmission. A questionnaire was applied through interviews to HCWs who worked in one of the five ICUs from a teaching hospital. Questions about influenza were deliberately dispersed among others that assessed several infectious agents. Forty-two HCWs were interviewed: nine physicians, ten nurses and 23 nursing technicians or auxiliaries. Among the 42 HCWs, 98% were aware of the potential transmission of influenza virus in the ICUs, but only 31% would indicate droplet precautions for patients with suspected infection. Moreover, only 31% of them had been vaccinated against influenza in the last campaign (2008). Nursing technicians or auxiliaries were more likely to have been vaccinated, both by univariate and multivariable analysis. When asked about absenteeism, only 10% of the study subjects stated that they would not go to work if they had an influenza-like illness. Those findings suggest that, in non-pandemic periods, influenza control in hospitals requires strategies that combine continuous education with changes in organizational culture.

H1N1 outbreak in a Swiss military boot camp--observations and suggestions

The A(H1N1)pdm09 influenza virus is a highly contagious pathogen which caused the 2009 influenza pandemic. The virus is known to affect mainly younger people and may be a problem in crowded living conditions. The aim of the study was to describe a major A(H1N1)pdm09 outbreak in a Swiss military boot camp and to develop suggestions for similar future situations.

Influenza Tipo A (H1N1)

Fil: Attorri, Silvia. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas

Attitudes to living and working in pandemic conditions among emergency prehospital medical care personnel

Introduction: Little is known about the risk perceptions and attitudes of healthcare personnel, especially of emergency prehospital medical care personnel, regarding the possibility of an outbreak or epidemic event. Problem: This study was designed to investigate pre-event knowledge and attitudes of a national sample of the emergency prehospital medical care providers in relation to a potential human influenza pandemic, and to determine predictors of these attitudes. Methods: Surveys were distributed to a random, cross-sectional sample of 20% of the Australian emergency prehospital medical care workforce (n = 2,929), stratified by the nine services operating in Australia, as well as by gender and location. The surveys included: (1) demographic information; (2) knowledge of influenza; and (3) attitudes and perceptions related to working during influenza pandemic conditions. Multiple logistic regression models were constructed to identify predictors of pandemic-related risk perceptions. Results: Among the 725 Australian emergency prehospital medical care personnel who responded, 89% were very anxious about working during pandemic conditions, and 85% perceived a high personal risk associated with working in such conditions. In general, respondents demonstrated poor knowledge in relation to avian influenza, influenza generally, and infection transmission methods. Less than 5% of respondents perceived that they had adequate education/training about avian influenza. Logistic regression analyses indicate that, in managing the attitudes and risk perceptions of emergency prehospital medical care staff, particular attention should be directed toward the paid, male workforce (as opposed to volunteers), and on personnel whose relationship partners do not work in the health industry. Conclusions: These results highlight the potentially crucial role of education and training in pandemic preparedness. Organizations that provide emergency prehospital medical care must address this apparent lack of knowledge regarding infection transmission, and procedures for protection and decontamination. Careful management of the perceptions of emergency prehospital medical care personnel during a pandemic is likely to be critical in achieving an effective response to a widespread outbreak of infectious disease.

Setting up a platform for plant-based influenza virus vaccine production in South Africa

Background During a global influenza pandemic, the vaccine requirements of developing countries can surpass their supply capabilities, if these exist at all, compelling them to rely on developed countries for stocks that may not be available in time. There is thus a need for developing countries in general to produce their own pandemic and possibly seasonal influenza vaccines. Here we describe the development of a plant-based platform for producing influenza vaccines locally, in South Africa. Plant-produced influenza vaccine candidates are quicker to develop and potentially cheaper than egg-produced influenza vaccines, and their production can be rapidly upscaled. In this study, we investigated the feasibility of producing a vaccine to the highly pathogenic avian influenza A subtype H5N1 virus, the most generally virulent influenza virus identified to date. Two variants of the haemagglutinin (HA) surface glycoprotein gene were synthesised for optimum expression in plants: these were the full-length HA gene (H5) and a truncated form lacking the transmembrane domain (H5tr). The genes were cloned into a panel of Agrobacterium tumefaciens binary plant expression vectors in order to test HA accumulation in different cell compartments. The constructs were transiently expressed in tobacco by means of agroinfiltration. Stable transgenic tobacco plants were also generated to provide seed for stable storage of the material as a pre-pandemic strategy. Results For both transient and transgenic expression systems the highest accumulation of full-length H5 protein occurred in the apoplastic spaces, while the highest accumulation of H5tr was in the endoplasmic reticulum. The H5 proteins were produced at relatively high concentrations in both systems. Following partial purification, haemagglutination and haemagglutination inhibition tests indicated that the conformation of the plant-produced HA variants was correct and the proteins were functional. The immunisation of chickens and mice with the candidate vaccines elicited HA-specific antibody responses. Conclusions We managed, after synthesis of two versions of a single gene, to produce by transient and transgenic expression in plants, two variants of a highly pathogenic avian influenza virus HA protein which could have vaccine potential. This is a proof of principle of the potential of plant-produced influenza vaccines as a feasible pandemic response strategy for South Africa and other developing countries.

Vulnerability : an issue for law and policy in pandemic planning?

The 2009 H!Nl 'swine flu' pandemic was the first influenza pandemic of the twenty-first centmy. Unlike the first influenza pandemic of the twentieth century, the so-called 'Spanish flu' which killed millions of people worldwide, the 2009 pandemic was relatively mild. While the mildness of the 2009 pandemic meant that the 'Yorld was spared from the impact of a high-mortality event that would cause widespread social and economic disruption, the 2009 pandemic did provide an opportunity to road-test pandemic readiness. In other work we have assessed Australia's pandemic plans and emergency management legislation, finding that both provide flexible and adaptive forms of regulation that are capable of adapting to the scale and severity of a pandemic or other public health emergency. 1 In this chapter we consider whether pandemic planning adequately addresses the needs of vulnerable individuals and groups, both within countries and between them. Central to this is the question of whether vulnerability is itself a useful concept for both law and policy, and if so, the implications of expressly incorporating the concept of vulnerability into pandemic planning.