The successful use of extra-corporeal membrane oxygenation in the management of a pregnant woman with severe H1N1 2009 influenza complicated by pneumonitis and adult respiratory distress syndrome

We report a case of H1N1 2009 influenza A, in a previously fit woman at 24 weeks of gestation, who presented atypically with abdominal pain. The infection was complicated by severe respiratory failure and acute respiratory distress syndrome, requiring ventilatory support, including extra-corporeal membrane oxygenation (ECMO). This was one of the first cases of severe H1N1 disease presenting in the UK. Use of extra-corporeal membrane oxygenation for the complications of H1N1 resulted in full maternal recovery and subsequent delivery of a healthy infant.     

The antibody response to pandemic H1N1 2009 influenza vaccine in adult organ transplant patients

Limited data are available regarding antibody response and the safety of the monovalent influenza A H1N1/09 vaccine for immunocompromised patients. In this study, the humoral response to this vaccine in solid organ transplant (SOT) recipients and healthy individuals was evaluated. Eighty‐two SOT recipients and 28 healthy individuals received two doses of the influenza A H1N1/09 AS03 adjuvanted vaccine containing 3.75 mg of haemagglutinin at a 3‐ to 4‐week interval. Serum samples were drawn at baseline and 3–4 weeks after the first and second vaccine doses. Seroprotective titres were measured with a haemagglutination inhibition. After the first dose seroprotective titres were observed in 69% of the SOT patients and in 96% of the healthy controls (P = 0.006), and increased after the second dose to 80% and 100%, respectively (P = 0.003). All controls and 77% of the SOT recipients achieved a ≥4‐fold titre rise after the first immunisation (P = 0.005). The vaccine was well tolerated and no acute rejection was observed. Influenza A H1N1/09 vaccine elicited a protective antibody response in the majority of SOT recipients, but the response was lower when compared with controls. A second dose significantly improved vaccine immunogenicity in SOT recipients. (ClinicalTrials.gov number: NCT01254955)     

Impact of the A (H1N1) pandemic influenza (season 2009–2010) on patients with cystic fibrosis

Background

Influenza, like other respiratory viral infections, can cause acute deterioration of lung function in patients with cystic fibrosis (CF). Previous studies on a small number of patients reported that most people with CF infected with A (H1N1) influenza experienced a mild course of disease.

Aim

To characterise the impact of A (H1N1) infection on CF in a large number of patients from different centres and countries.

Methods

CF centres accessing the web-site of the European Cystic Fibrosis Society (ECFS) were asked to report clinical data on patients with an ascertained diagnosis of influenza caused by the A (H1N1) virus. The study was web-based and data were collected through an electronic data sheet on the ECFS website.

Results

Twenty-five centres from 10 countries caring for 4698 patients with CF reported data on 110 patients (2.3%), median age 13 years (range 1–39 years). The prevalence of infection in each centre ranged from 0% to 9.4%. Only 8.8% of the patients had been vaccinated. The main symptoms were fever and respiratory exacerbation requiring IV antibiotics in 53% of the patients; 48% of the patients were hospitalised for an average of 12.9 days (range 2–56) and 31% required oxygen treatment during the time of the infection. Most of the patients recovered and FEV₁ 1 month after the infection was similar to that before the infection. However, 6 patients were admitted to ICU, 5 with mechanical ventilation. Three patients with severe respiratory disease died.

Conclusions

A (H1N1) influenza infection caused transient but significant morbidity in most of the patients with CF. However, in a small number of patients with severe lung disease, A (H1N1) influenza was associated with respiratory deterioration, mechanical ventilation and even death.     

Pandemic 2009 influenza H1N1 virus vaccination: compliance and safety in a single hemodialysis center

Background: Acceptance of vaccination against pandemic 2009 H1N1 influenza virus has been poor in some countries, perhaps because of concerns about safety of the new vaccine. Subjects and methods: We prospectively examined vaccination compliance and reasons for nonvaccination in the dialysis patients and the staff of a single hemodialysis unit, after on-site vaccination with a monovalent inactivated adjuvanted H1N1 vaccine. Safety profile was evaluated and compared to that of a control group without chronic kidney disease (CKD). Results: Vaccination acceptance among dialysis patients in our unit was 68% (110/161). Dialysis patients vaccinated against H1N1 had significantly higher compliance with vaccination for seasonal influenza and pneumococcus than those unvaccinated. Three out of 34 (9%) of the unit's staff received the vaccine. Fear of side effects was the main reason for not vaccinating in both groups, while several participants did not consider pandemic influenza a serious disease. At least one adverse reaction was observed in 37/110 (33.6%) of the vaccinated dialysis patients and in 22/42 (52.4%) of the non-CKD control group, p = 0.034. Local mild pain at injection site was the most common side effect of vaccination in both groups. All side effects were of short duration and no serious adverse reactions related to the vaccine or reactions of special interest occurred during the follow-up period. Conclusions: Our findings indicate that immunization against H1N1 virus in dialysis patients is safe and do not support the concerns about safety of the vaccine that was the main reason for nonvaccination in our study.     

Transplantation of solid organs procured from influenza A H1N1 infected donors

Following the influenza A H1N1 (swine flu) pandemic, there remains little evidence informing the safety of transplanting organs from donors suspected or diagnosed with H1N1. Limited guidelines from the major transplant societies leave the use of such organs at the discretion of individual transplant centres, and practice varies considerably both nationally and internationally. We present the largest published series of outcome following transplantation of organs from H1N1 positive donors and demonstrate that these organs can be transplanted safely and with good short-term outcome. We discuss our local policy for treatment of recipients with Oseltamivir.     

Factors Associated With H1N1 Influenza Vaccine Receipt in a High-Risk Population During the 2009-2010 H1N1 Influenza Pandemic

Background:

Persons with spinal cord injuries and disorders (SCI/D) are at high risk for respiratory complications from influenza. During pandemic situations, where resources may be scarce, uncertainties may arise in veterans with SCI/D.

Objective:

To describe concerns, knowledge, and perceptions of information received during the 2009-2010 H1N1 influenza pandemic and to examine variables associated with H1N1 vaccine receipt.

Methods:

In August 2010, a cross-sectional survey was mailed to a national sample of veterans with traumatic and nontraumatic SCI/D.

Results:

During the pandemic, 58% of veterans with SCI/D received the H1N1 vaccine. Less than two-thirds of non-H1N1 vaccine recipients indicated intentions to get the next season’s influenza vaccine. Being ≥50 years of age and depressed were significantly associated with higher odds of H1N1 vaccination. Being worried about vaccine side effects was associated with lower odds of H1N1 receipt. Compared to individuals who reported receiving an adequate amount of information about the pandemic, those who received too little information had significantly lower odds of receiving the H1N1 vaccine. Those who received accurate/clear information (vs confusing/conflicting) had 2 times greater odds of H1N1 vaccine receipt.

Conclusions:

H1N1 influenza vaccination was low in veterans with SCI/D. Of H1N1 vaccine nonrecipients, only 63% intend to get a seasonal vaccine next season. Providing an adequate amount of accurate and clear information is vital during uncertain times, as was demonstrated by the positive associations with H1N1 vaccination. Information-sharing efforts are needed, so that carry-over effects from the pandemic do not avert future healthy infection prevention behaviors.     

甲型H11感危重症患者机械通气治疗后发生气压伤的相关危险因素分析

目的：分析甲型H1N1流感危重症患者在机械通气时发生气压伤的危险因素.方法：对2009年11月-2010年2月山东省胸科医院ICU收治的15例行机械通气的甲型H1N1流感危重症患者按有无发生气压伤分成两组,对患者性别、年龄、28 d在院病死率、急性生理学和慢性健康状况评分、肺损伤评分、氧合指数及呼吸支持时肺部静态顺应性、呼吸频率、呼气末正压、最大吸气压力、潮气量和氧浓度指标进行回顾分析.结果：气压伤组患者的肺损伤评分、吸入氧浓度明显高于无气压伤组患者（P=0.001,P=0.008）,肺部静态顺应性（Cstat）要明显低于未出现气压伤的患者（P=0.024）,两组之间差异具有统计学意义.两组患者的年龄、性别、APACHEⅡ评分、呼气末正压、最大吸气压力、潮气量和呼吸频率之间差异无统计学意义（P均〉0.05）.结论：甲型H1N1流感病毒对肺组织的严重损害及其导致的肺静态顺应性下降可能是导致危重症患者机械通气时发生气压伤的重要因素.     

Experimental infection of clade 1.1.2 (H5N1), clade 2.3.2.1c (H5N1) and clade 2.3.4.4 (H5N6) highly pathogenic avian influenza viruses in dogs

Since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in Asia, the haemagglutinin (HA) gene of this virus lineage has continued to evolve in avian populations, and H5N1 lineage viruses now circulate concurrently worldwide. Dogs may act as an intermediate host, increasing the potential for zoonotic transmission of influenza viruses. Virus transmission and pathologic changes in HPAI clade 1.1.2 (H5N1)‐, 2.3.2.1c (H5N1)‐ and 2.3.4.4 (H5N6)‐infected dogs were investigated. Mild respiratory signs and antibody response were shown in dogs intranasally infected with the viruses. Lung histopathology showed lesions that were associated with moderate interstitial pneumonia in the infected dogs. In this study, HPAI H5N6 virus replication in dogs was demonstrated for the first time. Dogs have been suspected as a “mixing vessel” for reassortments between avian and human influenza viruses to occur. The replication of these three subtypes of the H5 lineage of HPAI viruses in dogs suggests that dogs could serve as intermediate hosts for avian–human influenza virus reassortment if they are also co‐infected with human influenza viruses.     

危重症甲型H1N1死亡1例

患者男,25岁,主因“发热、咳嗽、气短5天”于2009年11月20日下午18：40留我院观察。患者否认流行病学史,1周内未接触发热患者,周围密切接触者亦无发热。入院查体：体型肥胖,体温39℃,脉搏130次／分,呼吸50次／分,血压117／57mmHg;神清,查体合作,咽部充血。双扁桃体未见增大,双肺可及湿性啰音。采用Siemens床旁X线机摄胸部正位片示双侧肺炎（图1）;     

H1N1 infection in emergency surgery: A cautionary tale

Pandemic 2009 influenza A H1N1 has spread rapidly since its first report in Mexico in March 2009. This is the first influenza pandemic in over 40 years and it atypically affects previously healthy young adults, with higher rates of morbidity and mortality. The medical literature has been inundated with reports of H1N1 infection, the majority found in critical care and internal medicine journals with a relative paucity in the surgical literature. Despite this, it remains an important entity that can impact greatly on acute surgical emergencies. We present a case of previously healthy 31-year-old male who underwent open appendectomy. His post-operative recovery was complicated by acute respiratory distress syndrome secondary to H1N1 infection. This case report highlights the impact that H1N1 virus can have on acute surgical emergencies and how it can complicate the post-operative course.     

The Impact of Pandemic Influenza A H1N1 2009 on Australian Lung Transplant Recipients

Influenza A H1N1 2009 led to 189 deaths during the Australian pandemic. Community‐acquired respiratory viruses not only can cause prolonged allograft dysfunction in lung transplant recipients but have also been linked to bronchiolitis obliterans syndrome (BOS). We report the impact of the 2009 H1N1 pandemic on Australian lung transplant recipients. An observational study of confirmed H1N1 cases was conducted across five Australian lung transplant programs during the pandemic. An electronic database collected patient demographics, clinical presentation, management and outcomes up to a year follow‐up. Twenty‐four H1N1 cases (mean age 43 ± 14 years, eight females) were identified, incidence of 3%. Illness severity varied from upper respiratory tract symptoms only in 29% to lung allograft dysfunction (≥10% decline FEV1) in 75% to death in 5 (21%) cases (pre‐existing BOS grade 3, n = 4). Treatment with oseltamivir occurred in all but one case confirmed after death, reduced immunosuppression, n = 1, augmented corticosteroid therapy, n = 16, and mechanical/noninvasive ventilation, n = 4. There was BOS grade decline within a year in six cases (32%). In conclusion, Australian lung transplant recipients were variably affected by the H1N1 pandemic mirroring the broader community with significant morbidity and mortality. After initial recovery, a considerable proportion of survivors have demonstrated BOS progression.     

A Meta‐Analysis of the Prevalence of Influenza A H5N1 and H7N9 Infection in Birds

Despite a much higher rate of human influenza A (H7N9) infection compared to influenza A (H5N1), and the assumption that birds are the source of human infection, detection rates of H7N9 in birds are lower than those of H5N1. This raises a question about the role of birds in the spread and transmission of H7N9 to humans. We conducted a meta‐analysis of overall prevalence of H5N1 and H7N9 in different bird populations (domestic poultry, wild birds) and different environments (live bird markets, commercial poultry farms, wild habitats). The electronic database, Scopus, was searched for published papers, and Google was searched for country surveillance reports. A random effect meta‐analysis model was used to produce pooled estimates of the prevalence of H5N1 and H7N9 for various subcategories. A random effects logistic regression model was used to compare prevalence rates between H5N1 and H7N9. Both viruses have low prevalence across all bird populations. Significant differences in prevalence rates were observed in domestic birds, farm settings, for pathogen and antibody testing, and during routine surveillance. Random effects logistic regression analyses show that among domestic birds, the prevalence of H5N1 is 47.48 (95% CI: 17.15–133.13, P < 0.001) times higher than H7N9. In routine surveillance (where surveillance was not conducted in response to human infections or bird outbreaks), the prevalence of H5N1 is still higher than H7N9 with an OR of 43.02 (95% CI: 16.60–111.53, P < 0.001). H7N9 in humans has occurred at a rate approximately four times higher than H5N1, and for both infections, birds are postulated to be the source. Much lower rates of H7N9 in birds compared to H5N1 raise doubts about birds as the sole source of high rates of human H7N9 infection. Other sources of transmission of H7N9 need to be considered and explored.     

Infection Dynamics of Pandemic 2009 H1N1 Influenza Virus in a Two‐Site Swine Herd

Influenza A viruses are common causes of respiratory disease in pigs and can be transmitted among multiple host species, including humans. The current lack of published information on infection dynamics of influenza viruses within swine herds hinders the ability to make informed animal health, biosecurity and surveillance programme decisions. The objectives of this serial cross‐sectional study were to describe the infection dynamics of influenza virus in a two‐site swine system by estimating the prevalence of influenza virus in animal subpopulations at the swine breeding herd and describing the temporal pattern of infection in a selected cohort of growing pigs weaned from the breeding herd. Nasal swab and blood samples were collected at approximately 30‐day intervals from the swine breeding herd (Site 1) known to be infected with pandemic 2009 H1N1 influenza virus. Sows, gilts and neonatal pigs were sampled at each sampling event, and samples were tested for influenza virus genome using matrix gene RRT‐PCR. Influenza virus was detected in neonatal pigs, but was not detected in sow or gilt populations via RRT‐PCR. A virus genetically similar to that detected in the neonatal pig population at Site 1 was also detected at the wean‐to‐finish site (Site 2), presumably following transportation of infected weaned pigs. Longitudinal sampling of nasal swabs and oral fluids revealed that influenza virus persisted in the growing pigs at Site 2 for at least 69 days. The occurrence of influenza virus in neonatal pigs, but not breeding females, at Site 1 emphasizes the potential for virus maintenance in this dynamic subpopulation, the importance of including this subpopulation in surveillance programmes and the potential transport of influenza virus between sites via the movement of weaned pigs.     

Experimental infection of H5N1 and H5N8 highly pathogenic avian influenza viruses in Northern Pintail (Anas acuta)

The wide geographic spread of Eurasian Goose/Guangdong lineage highly pathogenic avian influenza (HPAI) clade 2.3.4.4 viruses by wild birds is of great concern. In December 2014, an H5N8 HPAI clade 2.3.4.4 Group A (2.3.4.4A) virus was introduced to North America. Long‐distance migratory wild aquatic birds between East Asia and North America, such as Northern Pintail (Anas acuta ), were strongly suspected of being a source of intercontinental transmission. In this study, we evaluated the pathogenicity, infectivity and transmissibility of an H5N8 HPAI clade 2.3.4.4A virus in Northern Pintails and compared the results to that of an H5N1 HPAI clade 2.3.2.1 virus. All of Northern Pintails infected with either H5N1 or H5N8 virus lacked clinical signs and mortality, but the H5N8 clade 2.3.4.4 virus was more efficient at replicating within and transmitting between Northern Pintails than the H5N1 clade 2.3.2.1 virus. The H5N8‐infected birds shed high titre of viruses from oropharynx and cloaca, which in the field supported virus transmission and spread. This study highlights the role of wild waterfowl in the intercontinental spread of some HPAI viruses. Migratory aquatic birds should be carefully monitored for the early detection of H5 clade 2.3.4.4 and other HPAI viruses.     

Complete genome sequence of a novel influenza A H1N2 virus circulating in swine from Central Bajio region,Mexico

The aim of this study was to perform the complete genome sequence of a swine influenza A H1N2 virus strain isolated from a pig in Guanajuato, México (A/swine/Mexico/GtoDMZC01/2014) and to report its seroprevalence in 86 counties at the Central Bajio zone. To understand the evolutionary dynamics of the isolate, we undertook a phylogenetic analysis of the eight gene segments. These data revealed that the isolated virus is a reassortant H1N2 subtype, as its genes are derived from human (HA, NP, PA) and swine (M, NA, PB1, PB2 and NS) influenza viruses. Pig serum samples were analysed by the hemagglutination inhibition test, using wild H1N2 and H3N2 strains (A/swine/México/Mex51/2010 [H3N2]) as antigen sources. Positive samples to the H1N2 subtype were processed using the field‐isolated H1N1 subtype (A/swine/México/Ver37/2010 [H1N1]). Seroprevalence to the H1N2 subtype was 26.74% in the sampled counties, being Jalisco the state with highest seroprevalence to this subtype (35.30%). The results herein reported demonstrate that this new, previously unregistered influenza virus subtype in México that shows internal genes from other swine viral subtypes isolated in the past 5 years, along with human virus‐originated genes, is widely distributed in this area of the country.     

甲型H1N1流感临床特征及流行病学分析

甲型H1N1流感在世界范围内的暴发已被广泛报道。截至7月27日22时,WHO确认甲型H1N1流感病毒已在全球160个国家感染,已有816例患者死亡。目前,仍不断有新发病例出现。为尽快了解其相关特性,总结防治经验,现对温州市收治的27例甲型H1N1流感确诊病例进行了回顾性分析。