H1N1 influenza pneumonia and bacterial coinfection

The model described by Bewick et al seems to be able to distinguish between H1N1 influenza-related pneumonia and non-H1N1 community acquired pneumonia (CAP) based on five criteria. However, bacterial infection in the influenza group has not been accurately excluded. Therefore, this model could misidentify these patients and lead to an inappropriate treatment. We conducted a prospective observational study to compare mixed pneumonia vs viral pneumonia. In the mixed pneumonia group patients were older, had higher levels of procalcitonine and higher scores of severity. In our cohort the model proposed by Bewick et al would not identify patients with coinfection.     

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.     

Pregnancy and H1N1 influenza: lessons to learn

Pregnancy, with or without additional complications, constitutes a high-risk condition for complications of influenza infection and warrants early intervention with neuraminidase inhibitors such as oseltamivir, if influenza is suspected. Treatment should not be delayed for laboratory confirmation. In South Africa, the high burden of HIV infection is a further complication.     

H1N1 influenza A presenting as bacterial tracheitis

Six cases of bacterial tracheitis (BT) occurring early in the 2009 flu season have been isolated in conjunction with the H1N1 strain of influenza A (H1N1). No previous H1N1 cases have presented as BT in the literature to date. We would like to discuss viral coinfection in BT patients and how this new strain may affect the rate and type of presentation encountered. The life-threatening potential of BT and the pandemic proportion of H1N1 highlight a possibly dangerous combination that should be recognized by the otolaryngology community. In hospitalized patients with presumed BT, consideration should be given to routine H1N1 testing and the addition of antiviral medication when indicated as this entity is further investigated.     

H1N1 vaccination in pediatric renal transplant patients

Background

Solid organ transplant recipients undergoing immunosuppressive therapy are considered to be at high risk of serious infectious complications. In 2009, a new influenza pandemic caused serious infections and deaths, especially among children and immunocompromised patients. Herein we have reported the safety and efficacy of a single-shot monovalent whole-virus vaccine against H1N1 infection in the pediatric renal transplant population.

Methods

In November and December 2009, we vaccinated 37 renal transplant children and adolescents and measured their antibody responses. Seroprotection, seroconversion, and seroconversion factors were analyzed at 21 days after vaccination.

Results

None of the vaccinated patients experienced vaccine-related side effects. None of the patients had an H1N1 influenza infection after vaccination. All of the patients showed elevations in antibody titer at 21 days after vaccination. In contrast, only 29.72% of the patients achieved a safe seroprotection level and only 18.75% a safe seroconversion rate. More intense immunosuppressive treatment displayed negative effect on seroprotection and seroconversion, and antibody production significantly increased with age. No other factor was observed to influence seroprotection.

Conclusions

We recommend vaccination of children and adolescent renal transplant recipients against H1N1 virus. However, a single shot of vaccine may not be sufficient; to achieve seroprotection, a booster vaccination and measurement of the antibody response are needed to assure protection of our patients.     

Swine H1N1 infection in a renal transplant recipient

Influenza pandemics have been observed in several periods throughout history. The first influenza pandemic of the 21st century began in Mexico in 2009 and has spread rapidly all over the world. Swine H1N1 has been officially declared a pandemic by the World Health Organization in June 2009. As has been observed in previous pandemics, pregnant women, adolescents, and immunosuppressed individuals are affected more severely in this pandemic. Despite several reports about the pandemic, there have not been any reports of swine H1N1 infection in individuals who underwent renal transplant. The aim of the current study was to present oseltamivir therapy in a swine H1N1-infected patient who underwent renal transplant 10 months earlier, and was thus under immunosuppressive treatment. To the best of our knowledge, this is the first case report of a swine H1N1 infection in a renal transplant recipient.     

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。     

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.