Pertussis vaccine research

The mechanisms of infection and immunity in pertussis are not well understood, and as a result, the development of a new, improved vaccine is difficult. This paper describes the limitations of currently available vaccines, and outlines the problems associated with the introduction of new prophylactics, such as defining the bases of toxicity and efficacy and organizing meaningful clinical trials. Until these problems are resolved, efforts are needed to improve currently available whole-cell vaccines. The possible role of passive immunity in the control of the disease is also discussed.     

What to think if the results of the National Institutes of Health randomized trial of methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococcus control measures are negative (and other advice to young epidemiologists): a review and an au revoir.

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) infections continues to rise in National Nosocomial Infections Surveillance system hospitals, and these pathogens are reportedly causing more than 100,000 infections and many deaths each year in US healthcare facilities. This has led some to insist that control measures are now urgently needed, but several recent articles have suggested that isolation of patients does not work, is not needed, or is unsafe, or that a single cluster-randomized trial could be used to decide such matters. At least 101 studies have reported controlling MRSA infection and 38 have reported controlling VRE infection by means of active detection by surveillance culture and use of isolation for all colonized patients in healthcare settings where the pathogens are epidemic or endemic, in academic and nonacademic hospitals, and in acute care, intensive care, and long-term care settings. MRSA colonization and infection have been controlled to exceedingly low levels in multiple nations and in the state of Western Australia for decades by use of active detection and isolation. Studies suggesting problems with using such data to control MRSA colonization and infection have their own problems, which are discussed. Randomized trials are epidemiologic tools that can sometimes provide erroneous results, and they have not been considered necessary for studying isolation before it is used to control other important infections, such as tuberculosis, smallpox, and severe acute respiratory syndrome. No single epidemiologic study should be considered definitive. One should always weigh all available evidence. Infection with antibiotic-resistant pathogens such as MRSA and VRE is controllable to a low level by active detection and isolation of colonized and infected patients. Effective measures should be used to minimize the morbidity and mortality attributable to these largely preventable infections.     

Risky business: using necessarily imprecise casualty counts to estimate occupational risks for HIV-1 infection

Although the genesis of healthcare worker anxiety regarding occupational risks of HIV-1 infection is clear, the reasons for continued insistence on a meticulous "casualty count" become less clear with time. One could, in fact, argue that the precise number of such infections has become virtually meaningless, because the routes of occupational/nosocomial transmission of HIV-1 and the magnitude of risk for infection following an adverse exposure in the healthcare setting have been well-characterized. Nevertheless, with the substantial limitations of these data clearly in mind, we have summarized the numbers of healthcare workers reported to have HIV-1 infection in each of the above categories in Table 2. The likelihood that an individual case represents true occupational infection decreases as one moves down the table. Having waded through the depths of this literature, we have reached the conclusion that, of the available data, the magnitude of risk for occupational HIV-1 infection remains the single most useful and instructive statistic available. Longitudinal cohort studies of HCWs involved in the day-to-day care of HIV-1-infected patients and in the handling and processing of specimens from such patients provide the best available evidence regarding the magnitude of risk for transmission of this virus in the healthcare setting. Fourteen prospective studies are currently in progress, with approximately 2,000 HCWs enrolled (Table 4). Six HCWs enrolled in these studies have developed serologic evidence of HIV-1 infection following percutaneous exposures, yielding an infection rate per participant of 0.32% and an infection rate per exposure of 0.31%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Vaccination strategies to protect children against seasonal and pandemic influenza

To protect children against infection with seasonal influenza viruses, this age group is vaccinated annually in some countries. However, currently used inactivated seasonal influenza vaccines do not protect well against antigenically distinct pandemic influenza virus strains. Furthermore, annual vaccination may prevent infection with seasonal influenza viruses and subsequently the induction of heterosubtypic immunity. Therefore, the development of influenza vaccines that induce broad protective immunity should be considered a priority. In the absence of such vaccines children that are vaccinated annually against seasonal influenza should in a pandemic scenario also receive pandemic vaccines as soon as these become available. In order to protect young infant under six months of age for which no vaccines are registered at present, vaccination of pregnant women should be considered. This would afford protection through maternally derived antibodies. In addition, vaccination of close family members of young infants is recommended, to prevent transmission within the household.     

Pediatric AIDS: The professional responsibilities of child caregivers to children and families

Information about the nature and control of AIDS is now available to the general public. Policies regarding the physical care of AIDS victims are also available to health care professionals. Unfortunately, information about professional issues like acceptance of AIDS victims, confidentiality, and family support is less available. One audience in particular need of such information is child caregivers who, in the years ahead, can expect to see an increasing number of children who are infected with the HIV virus. In this paper, the author addresses the professional responsibilities of child caregivers who care for children with AIDS or HIV infection.     

Optimizing delivery of care for patients with MRSA infection: focus on transitions of care

Staphylococcus aureus is among the most prevalent pathogens isolated from hospitalized patients; those infected with methicillin-resistant strains have longer hospital stays and higher total costs compared with those infected by methicillin-susceptible strains. A multidisciplinary team of health care providers, including hospitalists and other hospital-based physicians, clinical pharmacists, infectious disease specialists, infection control professionals, and case managers, is key to improving treatment and outcomes in these patients. Optimizing transitions of care for hospitalized patients with S aureus infections can improve quality and reduce total costs of care. Hospital length of stay can be shortened by initiating timely, appropriate empiric therapy and by transitioning suitable patients to outpatient antimicrobial therapy. The number of hospitalizations can be reduced by identifying patients who are suitable candidates for initial outpatient antimicrobial therapy. Consistent with good antimicrobial stewardship, the risk of resistance can be minimized by de-escalating empiric therapy to a more narrow-spectrum agent once culture and susceptibility testing results are known. There are several antimicrobial agents available for the management of S aureus infections, including methicillin-resistant S aureus. Consideration of these agents' characteristics may facilitate optimal transition of patients through health care settings.     

EURIDIKI,a backward glance – or: how theory and practice came together

The advent of intensive care medicine dates back some 40 years. The rising number of immunoincompetent patients who had to undergo intensive care treatment highlighted the need to focus on the serious problem of nosocomial infections. At that time not only did the majority of intensive care physicians have a lack of knowledge of the fundamentals of infectiology, but also there was also no behavioral guideline available. There were no recommendations available for infection prevention, or if they were they contradicted, in some cases to a considerable and confusing extent, existing guidelines.EURIDIKI, founded in 1979 by H.-J. Molitor in Vienna, was one of the first initiatives aimed at bringing together experts from the field of hospital hygiene and intensive care medicine. The declared goal was to formulate implementable behavioral rules for correct hygiene practices in intensive care units and to give doctors and nurses a sense of confidence when discharging their everyday duties. To assure effective prophylaxis against hospital infections, EURIDIKI believes that, based on its experiences, it is not only of clinical treatment principles that adequate knowledge is needed but also of the infection risks they pose. Doctors as well as assistant personnel must be conversant with disinfection and sterilization methods and indications. Likewise, experience is needed in diagnosis and differential diagnosis of infections, with associated immunological implications, microbiology, proper collection and transport of clinical samples (such as body secretions), including interpretation of microbiological and infection/immunological results. Of paramount importance is precise knowledge of antimicrobial chemotherapy, of dosages tailored to the respective case, of potential development of resistance and of other adverse side effects. On the other hand, the external infection control experts who are consulted by hospitals should be conversant with not only the priorities governing infection control rules, but must also know how to implement these. This means they must be familiar with the diagnostic and therapeutic principles and procedures underlying medical and nursing measures, bearing in mind the existing structural conditions and human resources availability.     

Risks associated with hepatitis infection in patients with hepatitis C and opportunities for prophylaxis

Patients with chronic hepatitis C remain at risk of acquiring hepatitis A infection and additional liver injury. The estimated risk of HAV infection in HCV patients is similar to that in general population but may be higher in anti-HCV positive drug users. Despite some controversies available data indicate that hepatitis A infection is associated with much higher incidence of hepatitis fulminans and mortality rate in individuals with pre-existing liver disease. In Poland about 60% of all HCV-infected adults have natural immunity to HAV, however majority of those under 35 years majority remains unprotected. Currently available inactivated HAV vaccine proved to be highly immunogenic and safe in patients with hepatitis C. The vaccination should be administered in each unprotected patient upon diagnosis of HCV infection.     

Management of oral antiretroviral administration in patients with swallowing disorders or with an enteral feeding tube

HIV infection has evolved into a chronic disease with comorbidities since the combination antiretroviral therapy era. Complications still occur and patients may need to be admitted to an intensive care unit. Acute respiratory failure is the first cause of these admissions, questioning the administration of solid oral dosage formulations. This issue is also observed in geriatric units where the prevalence of dysphagia is high and underestimated. The problem of antiretroviral administration is critical: altered solid oral dosage formulations and/or administration via enteral feeding tubes are sometimes the only option. The aim is to help manage antiretroviral treatment in unconscious or intubated patients and those with swallowing disorders who are hospitalized in intensive care units or geriatric units. This review provides information on the main antiretroviral regimens and on practical and legal aspects of manipulating solid oral dosage formulations and administration via enteral feeding tubes. Alternatives to the solid formulation are available for most of the 27 oral antiretrovirals available, or manufacturers provide recommendations for patients who are unable to swallow. Manipulation of solid oral dosage formulations such as crushing tablets or opening capsules and administration via feeding tubes are frequently reported but should be the last option for safety and liability issues. Before any off-label administration of a drug, physicians should consider alternatives to the solid oral dosage formulation and check whether the drug can be altered. Therapeutic monitoring is important in this particular setting as the pharmacokinetic profile of drugs is difficult to predict.     

Risk of transmission associated with live attenuated vaccines given to healthy persons caring for or residing with an immunocompromised patient.

OBJECTIVE: Persons who receive live attenuated vaccine may occasionally transmit the vaccine strain to others. The risk of such transmission is a concern, especially for persons who provide care to immunocompromised patients (ie, family and healthcare workers [HCWs]). Since the Advisory Committee on Immunization Practices released guidelines 10 years ago, several new live attenuated products have been introduced, and additional information on older vaccines has become available. To better define the risk of transmission associated with live vaccines, we reviewed the currently available literature. RESULTS: A review of the medical literature revealed no major risk of transmission associated with any live attenuated vaccine. A theoretical risk continues to exist for the live attenuated intranasal influenza vaccine and the smallpox vaccine. CONCLUSIONS: The available data support routine vaccination with live attenuated vaccines for all household contacts of immunocompromised patients and for HCWs caring for such patients. The benefit for immunocompromised patients of providing herd immunity against this group of potentially devastating pathogens outweighs the risk, if any, of secondary transmission.     

粒细胞缺乏患者入住无菌病房医院感染危险因素分析及护理对策

目的探讨粒细胞缺乏患者入住无菌病房行保护性隔离期间发生医院感染的环节、相关因素及护理对策方法采用前瞻性和回顾性调查的方法,对2010年1月～2011年7月我院血液科入住无菌病房的106例粒细胞缺乏患者入住无茵病房期间发生的医院感染的相关危险因素进行统计分析结果106例入住无菌病房的粒细胞缺乏患者发生院内感染77例次,医院感染发病率为72.6%,其中主要以呼吸道感染为主,占41.6%,入住无菌病房期间:患者自身免疫力低下、不同患者交叉感染、自我防护知识欠缺、未严格遵守无菌病房操作规范、医护人员手卫生不达标等是粒细胞缺乏患者院内感染的高危因素。结论粒细胞缺乏入住无菌病房的患者相关宣教效果及其遵医行为的养成、医护人员严格执行无菌操作、执行手卫生等在预防粒细胞缺乏患者入住无菌病房期间发生院内感染有重要作用。     

Towards immunotherapy for chronic hepatitis B virus infections

Chronic liver disease and hepatocellular carcinoma associated with chronic hepatitis B virus (HBV) infection are among the most serious human health problems in highly endemic regions. Although, effective vaccines against HBV have been available for many years, over 350 million people still remain persistently infected with HBV. Current therapies fail to provide long-term control of viral replication in most patients. Viral persistence has been associated with a defect in the development of HBV-specific cell-mediated immunity. Vaccine-based strategies to boost or to broaden the weak virus-specific T cell response of patients with chronic hepatitis B are proposed as a means of terminating this persistent infection.     

Glycine as an inherent component of bacterial lipopolysaccharides

The amino-acylation of bacterial polysaccharide antigens and the biological role of this phenomenon are poorly understood, although it might be relevant in the processes of the infection and immunity. Due to the lability of ester linked substituents on glyco-conjugate antigens, usually such groups escaped detection during routine structural investigation. Among the only few data available, these on the occurrence of glycine in endotoxic lipopolysaccharides of Gram-negative bacteria are well documented. This work summarises these data on glycine as an integral constituent of bacterial LPS and also on some other amino acid esters in teichoic acids and phosphatidylglycerol of Gram-positive bacteria. The possible functions are discussed of such noncarbohydrate ester linked substituents in bacterial antigens.     

Incidence and clinical implication of nosocomial infections associated with implantable biomaterials - catheters, ventilator-associated pneumonia, urinary tract infections

Health care associated infections, the fourth leading cause of disease in industrialised countries, are a major health issue. One part of this condition is based on the increasing insertion and implantation of prosthetic medical devices, since presence of a foreign body significantly reduces the number of bacteria required to produce infection. The most significant hospital-acquired infections, based on frequency and potential severity, are those related to procedures e.g. surgical site infections and medical devices, including urinary tract infection in catheterized patients, pneumonia in patients intubated on a ventilator and bacteraemia related to intravascular catheter use. At least half of all cases of nosocomial infections are associated with medical devices.Modern medical and surgical practices have increasingly utilized implantable medical devices of various kinds. Such devices may be utilized only short-time or intermittently, for months, years or permanently. They improve the therapeutic outcome, save human lives and greatly enhance the quality of life of these patients. However, plastic devices are easily colonized with bacteria and fungi, able to be colonized by microorganisms at a rate of 0.5 cm per hour. A thick biofilm is formed within 24 hours on the entire surface of these plastic devices once inoculated even with a small initial number of bacteria.The aim of the present work is to review the current literature on causes, frequency and preventive measures against infections associated with intravascular devices, catheter-related urinary tract infection, ventilator-associated infection, and infections of other implantable medical devices. Raising awareness for infection associated with implanted medical devices, teaching and training skills of staff, and establishment of surveillance systems monitoring device-related infection seem to be the principal strategies used to achieve reduction and prevention of such infections. The intelligent use of suitable antiseptics in combination with medical devices may further support reduction and prevention of such infections. In addition to reducing the adverse clinical outcomes related with these infections, such reduction may substantially decrease the economic burden caused by device-related infection for health care systems.     

Enteral nutrition in the cardiothoracic intensive care unit: challenges and considerations

Cardiovascular disease is a common preexisting condition among hospitalized patients. Acute myocardial infarction and cardiac surgery account for 2 of the most common reasons patients are admitted to the intensive care unit. Determining how and when to feed these patients is a constant challenge presented to nutrition support practitioners. Enteral nutrition has emerged as the preferred route of feeding particularly in critical illness. By providing enteral nutrition instead of parenteral nutrition, the natural physiologic pathway is being followed and gut immunity preserved. However, obstacles such as upper gastrointestinal intolerance, hypoperfusion vasopressor support, and glycemic control make the task of initiating feeds a challenge. Once a patient has successfully tolerated feeds, the nutrition support clinician must still determine how much to feed and if specialty formulas such as those containing omega-3 fatty acids are beneficial for their patient. The purpose of this review is to present recent research on the feeding challenges in the critical care population with a focus on the cardiothoracic population and an emphasis on improving patient outcomes.     

How useful are microbial filters in respiratory apparatus?

Following an outbreak of hepatitis C in surgical patients in Australia, it has been suggested that transmission can take place as a result of contaminated anaesthetic circuits. It has therefore been recommended that filters should be placed between patients and breathing systems with a new filter being used for each patient. Although nosocomial pneumonia is a major manifestation of hospital-acquired infection, it is unclear whether contamination of ventilator circuits is implicated in the aetiology of this condition. Some data suggest that bacteria cannot survive well in anaesthetic circuits and several studies have failed to demonstrate significant contamination of circuits in clinical situation. Several outbreaks of pneumonia related to contaminated anaesthetic equipment have been described, but many of these were controlled by appropriate decontamination of the respiratory equipment. Although ventilator filters are used by the majority of intensive care units and filters do have the ability to filter bacteria and viruses, there are few data suggesting that the use of filters reduce the rate of pulmonary infections in long-term ventilated patients. Furthermore, to change filters between operations would have significant financial implications, and there is no conclusive evidence that they would reduce cross infection. Until more data are available on the role of filters in both long-term ventilated patients and operations, standard hygienic measures such as appropriate disinfection protocols are still the most effective way of reducing ventilator-associated infections.     

Medicare's First Half Year

Abstract

Staphylococcus aureus is among the most prevalent pathogens isolated from hospitalized patients; those infected with methicillin-resistant strains have longer hospital stays and higher total costs compared with those infected by methicillin-susceptible strains. A multidisciplinary team of health care providers, including hospitalists and other hospital-based physicians, clinical pharmacists, infectious disease specialists, infection control professionals, and case managers, is key to improving treatment and outcomes in these patients. Optimizing transitions of care for hospitalized patients with S aureus infections can improve quality and reduce total costs of care. Hospital length of stay can be shortened by initiating timely, appropriate empiric therapy and by transitioning suitable patients to outpatient antimicrobial therapy. The number of hospitalizations can be reduced by identifying patients who are suitable candidates for initial outpatient antimicrobial therapy. Consistent with good antimicrobial stewardship, the risk of resistance can be minimized by de-escalating empiric therapy to a more narrow-spectrum agent once culture and susceptibility testing results are known. There are several antimicrobial agents available for the management of S aureus infections, including methicillin-resistant S aureus. Consideration of these agents' characteristics may facilitate optimal transition of patients through health care settings.     

Cell-mediated protection in influenza infection

Current vaccine strategies against influenza focus on generating robust antibody responses. Because of the high degree of antigenic drift among circulating influenza strains over the course of a year, vaccine strains must be reformulated specifically for each influenza season. The time delay from isolating the pandemic strain to large-scale vaccine production would be detrimental in a pandemic situation. A vaccine approach based on cell-mediated immunity that avoids some of these drawbacks is discussed here. Specifically, cell-mediated responses typically focus on peptides from internal influenza proteins, which are far less susceptible to antigenic variation. We review the literature on the role of CD4+ and CD8+ T cell-mediated immunity in influenza infection and the available data on the role of these responses in protection from highly pathogenic influenza infection. We discuss the advantages of developing a vaccine based on cell-mediated immune responses toward highly pathogenic influenza virus and potential problems arising from immune pressure.     

Approach to fecal incontinence and constipation in older hospitalized patients

Although constipation and fecal incontinence are commonly encountered in older hospitalized patients, there is a paucity of clinical studies in this field. In this article we discuss the approach to and management of patients with these problems based on evidence and studies performed on patients in the ambulatory care setting, nursing home setting, and our experience. Our recommendations are applicable to older hospitalized patients. Successful management of these patients depends on identifying and treating underlying cause(s), such as infection, dietary factors, medication, or immobility-induced incontinence, constipation, or fecal impaction. For a hospitalized patient, a digital rectal examination should be performed to rule out fecal impaction and overflow incontinence. If there is no impaction but a weak anal sphincter, stool softeners or laxatives should be discontinued, as they cause diarrhea/fecal incontinence. In a patient with diarrhea/incontinence and suspected infection, management includes checking stool for Clostridium difficile toxin, E0157, ova and parasites, and culture. If the patient is on enteral nutrition, osmotic diarrhea-induced incontinence should be considered. Nursing care includes use of absorbent pads, special undergarments, anal hygiene, and skin care. Medications such as loperamide or diphenoxylate/atropine are useful for diarrhea with incontinence. Laxatives (eg, polyethylene glycol, lactulose), secretagogues (eg, lubiprostone), enemas, suppositories, and timed toileting assistance may be effective for constipation. Despite appropriate management, older hospitalized patients may remain incontinent because of dementia, immobility, or comorbid issues. Treatment should be tailored to the underlying mechanism(s) and needs of each patient.