Nosocomial influenza in children

Influenza immunization of healthcare personnel in the post-COVID-19 pandemic era: Still a lot to do!

Healthcare-associated influenza is frequently encountered in healthcare settings with significant morbidity and mortality among vulnerable patients, absenteeism among healthcare personnel (HCP), and interruption of healthcare services. Numerous investigations indicate that nosocomial outbreaks are often traced to HCP. Despite the international and national endorsements, seasonal influenza vaccine acceptance among HCP continues suboptimal worldwide. Infection control is the major objective for healthcare risk management in order to guarantee patient safety, limit the cost of hospitalization and assurance health management in controlling influenza seasons. Vigilance and anticipation are required as globally we are moving from a reactive COVID-19 pandemic response phase to one of planning for the co-circulation of viral respiratory infections. Declining to understand HCP perception of influenza risk and acceptance of vaccination might have impact patient safety as well as healthcare services.

Nosocomial influenza in a pediatric general ward: Effects of isolation and cohort placement of children with influenza

OBJECTIVE

Many studies have described nosocomial outbreaks of influenza in specialized wards. We evaluated nosocomial transmission of influenza in a pediatric general ward.

DESIGN

Retrospective observational study.

SETTING

Single secondary hospital.

PATIENTS

The study included 814 hospitalized children with influenza between September 2015 and August 2020.

METHODS

The medical records of the included children were retrospectively reviewed, and clinical characteristics of children with community-acquired (CA) influenza and hospital-acquired (HA) influenza were determined. The room of each included child during hospitalization was traced to identify the children exposed to them.

RESULTS

CA influenza and HA influenza were diagnosed in 789 (96.9%) and 25 (3.1%) children, respectively. Among children with CA influenza, 691 (87.6%) were isolated or place in a cohort on admission. In total, 98 children (12.4%) admitted to multibed rooms exposed 307 children with noninfluenza diseases to influenza during 772 patient days; 3 exposed children (1.0%) were diagnosed with HA influenza. Including these 3 children, 25 children (19 without definite in-hospital exposure to influenza and 3 exposed to other children with HA influenza) were diagnosed with HA influenza, and 11 (44.0%) exposed 31 children with noninfluenza diseases to influenza for 85 patient days. Also, 3 exposed children (9.7%) were diagnosed with HA influenza, a significantly higher rate than that for CA influenza (P = .005). The clinical characteristics were comparable between children with HA influenza and those with CA influenza.

CONCLUSIONS

Cohort placement of children with influenza in a pediatric general ward can be effective in controlling nosocomial transmission of influenza. However, control measures for children with HA influenza should be emphasized.

Influenza Vaccination Programs for Healthcare Personnel: Organizational Issues and Beyond

Healthcare personnel (HCP) are a high priority group for influenza vaccination aiming to protect them but also to protect vulnerable patients and healthcare services from healthcare-associated influenza and HCP absenteeism. Multi-component influenza vaccination programs targeting behavioral, organizational, and administrative barriers are critical, if influenza vaccination rates among HCP are to be raised on a sustained basis. Mandatory influenza vaccination policy is the only single intervention that can achieve high and sustainable vaccination rates in HCP in short term. In this article, we provide an overview of issues pertaining to influenza vaccination of HCP, with an emphasis on organizational issues of influenza vaccination programs.

The epidemiological and clinical characteristics of the hospital-acquired influenza infections: A systematic review and meta-analysis

BACKGROUND

The hospital-acquired influenza (HAI) were usually contributed to severe outcomes among the inpatients. Here, we performed a meta-analysis to summarize and quantify the epidemiological and clinical characteristics of HAI.

METHODS

We performed a literature search thorough PubMed, Web of Science, Cochrane Library, Embase, Scopus and China National Knowledge Infrastructure (CNKI), and Wanfang databases for observational studies. Random/fix-effects models were used to obtain pooled proportion, odds ratio (OR), and weighted mean difference (WMD).

RESULTS

A total of 14 studies involving 1483 HAI and 71849 non-hospital-acquired influenza infections (NHAI) cases were included.The proportion of the HAI among the influenza cases was 11.38% (95% confidence interval [CI]: 5.19%-19.55%) and it was increased after 2012 (6.15% vs 12.72%). The HAI cases were significantly older (WMD = 9.51, 95% CI: 0.04-18.98) and the patients with chronic medical diseases were at increased risk of HAI (OR = 1.85, 95% CI: 1.57-2.19). Among them, metabolic disorders (OR = 8.10, 95% CI: 2.46-26.64) ranked the highest danger, followed by malignancy (OR = 3.18, 95% CI: 2.12-4.76), any chronic diseases (OR = 2.81, 95% CI: 1.08-9.31), immunosuppression (OR = 2.13, 95% CI: 1.25-3.64), renal diseases (OR = 1.72, 95% CI:1.40-2.10), heart diseases (OR = 1.52, 95% CI: 1.03-1.44), and diabetes (OR = 1.22, 95% CI: 1.03-1.44). The HAI cases were more likely to experience longer hospital stay (WMD = 10.23, 95% CI: 4.60-15.85) and longer intensive care unit (ICU) stay (WMD = 2.99, 95% CI: 1.50-4.48). In the outcomes within 30 days, those population was still more likely to receive hospitalization (OR = 6.55, 95% CI: 5.19-8.27), death in hospital (OR = 1.99, 95% CI: 1.65-2.40) but less likely to discharged (OR = 0.20, 95% CI: 0.16-0.24).

CONCLUSION

The proportion of the HAI among the influenza cases was relatively high. Reinforcement of the surveillance systems and vaccination of the high-risk patients and their contacts are necessary for the HAI control.

Self-reported immunity and opinions on vaccination of hospital personnel among paediatric healthcare workers in Denmark

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Vaccination of healthcare workers prevents the spread of infections in hospitals.

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A forth of healthcare workers reported to be non-immune to vaccine-preventable diseases.

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Nine out of 10 employees supported vaccination of non-immune healthcare workers.

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National recommendations for vaccination of healthcare workers in Denmark are needed.

Background

Denmark has no general recommendations for vaccination of healthcare workers (HCWs). We explored the self-reported immunity to varicella, measles, mumps, and rubella, reasons for receiving the influenza vaccine or not, and opinions on vaccination of HCWs against varicella, MMR, pertussis, diphtheria, and influenza among staff from departments with a high risk of exposure to infectious agents.

Methods

From May 2019 to August 2019, a structured questionnaire was distributed to clinical and non-clinical HCWs at a tertiary and a general paediatric department in Denmark. Self-reported immunity was defined as either previous infection or vaccination against the disease.

Results

Of 619 employed HCWs, 555 (90%) were included. A large proportion were unsure of or denied previous vaccination or infection with measles (20.1%), mumps (30.2%), rubella (21.4%), varicella (12.1%), pertussis (44.1%), and diphtheria (32.1%). Non-clinical personnel and employees born in 1974–1983 had the lowest level of self-reported immunity. Mandatory vaccination of non-immune HCWs was approved by 54–68.9% of participants, and any kind of vaccination (mandatory or as an offer at hospitals) was approved of up to 95.3% of all participants depending on the disease. During the season 2018/19, 214 (38.6%) HCWs received the influenza vaccine, including 20.3% of non-clinical staff, 34.8% of nurses and 56.5% of doctors (P < 0.001). Reasons for lack of vaccine uptake were mainly employees considering themselves rarely sick, the vaccine was not regarded as necessary, forgetfulness or lack of time. Only 37.8% was in favour of mandatory influenza vaccination.

Conclusions

A large proportion of paediatric HCWs were not aware of their immune status against important vaccine-preventable diseases. >90% supported vaccination of HCWs, with two out of three supporting mandatory MMR, pertussis and diphtheria vaccination. Better information and an official immunisation policy of non-immune HCWs in Denmark is warranted.

Underdetection of laboratory-confirmed influenza-associated hospital admissions among infants: a multicentre, prospective study

BACKGROUND

Since influenza often presents non-specifically in infancy, we aimed to assess the extent to which existing respiratory surveillance platforms might underestimate the frequency of severe influenza disease among infants.

METHODS

The Influenza and Respiratory Syncytial Virus in Infants (IRIS) study was a prospective observational study done at four hospitals in Albania, Jordan, Nicaragua, and the Philippines. We included acutely ill infants aged younger than 1 year admitted to hospital within 10 days or less of illness onset during two influenza seasons (2015-16 and 2016-17) in Albania, Jordan, and Nicaragua, and over a continuous 34 week period (2015-16) in the Philippines. We assessed the frequency of influenza virus infections by real-time RT-PCR (rRT-PCR) and serology. The main study outcome was seroconversion, defined as convalescent antibody titres more than or equal to four-fold higher than acute sera antibody titres, and convalescent antibody titres of 40 or higher. Seroconverison was confirmed by haemagglutination inhibition assay for influenza A viruses, and by hemagglutination inhibition assay and microneutralisation for influenza B viruses.

FINDINGS

Between June 27, 2015, and April 21, 2017, 3634 acutely ill infants were enrolled, of whom 1943 were enrolled during influenza seasons and had complete acute-convalescent pairs and thus were included in the final analytical sample. Of the 1943 infants, 94 (5%) were influenza-positive by both rRT-PCR and serology, 58 (3%) were positive by rRT-PCR-only, and 102 (5%) were positive by serology only. Seroconversion to at least one of the influenza A or B viruses was observed among 196 (77%) of 254 influenza-positive infants. Of the 254 infants with influenza virus, 84 (33%) only had non-respiratory clinical discharge diagnoses (eg, sepsis, febrile seizures, dehydration, or other non-respiratory viral illness). A focus on respiratory diagnoses and rRT-PCR-confirmed influenza underdetects influenza-associated hospital admissions among infants by a factor of 2·6 (95% CI 2·0-3·6). Findings were unchanged when syndromic severe acute respiratory infection criteria were applied instead of clinical diagnosis.

INTERPRETATION

If the true incidence of laboratory-confirmed influenza-associated hospital admissions among infants is at least twice that of previous estimates, this substantially increases the global burden of severe influenza and expands our estimates of the preventive value of maternal and infant influenza vaccination programmes.

FUNDING

US Centers for Disease Control and Prevention.

The role of healthcare providers in HPV vaccination programs - A meeting report

The Human Papillomavirus (HPV) Prevention and Control Board convened a meeting in Bucharest, Romania (May 2018), to discuss the role of healthcare providers (HCPs) in prevention programs, with a focus on HPV vaccination and cervical cancer screening. International and local experts discussed the role that HCPs can play to increase the uptake of HPV vaccine and screening. Experts recommended: 1) increasing HCP norms of getting vaccinated; 2) training providers to make effective recommendations; 3) making culturally appropriate materials available, in local languages; and 4) centralizing and coordinating education and information material, to direct both HCPs and the general public to the best material available.

Molecular characterization of a nosocomial outbreak of influenza B virus in an acute care hospital setting

Aim

To describe a hospital outbreak of influenza B virus (InfB) infection during season 2015/2016 by combining clinical and epidemiological data with molecular methods.

Methods

Twenty patients diagnosed with InfB from a hospital outbreak over a four-week-period were included. Nasopharyngeal samples (NPS) positive for InfB by multiplex real-time polymerase chain reaction were sent for lineage typing and whole genome sequencing (WGS). Medical records were reviewed retrospectively for data regarding patient characteristics, localization, exposure and outcome, and assembled into a timeline. In order to find possible connections to the hospital outbreak, all patients with a positive NPS for influenza from the region over an extended time period were also reviewed.

Findings

All 20 cases of InfB were of subtype B/Yamagata, and 17 of 20 patients could be linked to each other by either shared room or shared ward. WGS was successful or partially successful for 15 of the 17 viral isolates, and corroborated the epidemiological link supporting a close relationship. In the main affected ward, 19 of 75 inpatients were infected with InfB during the outbreak period, resulting in an attack rate of 25%. One probable case of influenza-related death was identified.

Conclusion

InfB may spread within an acute care hospital, and advanced molecular methods may facilitate assessment of the source and extent of the outbreak. A multi-faceted approach, including rapid diagnosis, early recognition of outbreak situations, simple rules for patient management and the use of regular infection control measures, may prevent nosocomial transmission of influenza virus.

Isolation Precautions for Visitors to Healthcare Settings

Visitors may be involved in infection transmission within healthcare settings; however, there is currently limited published data on this subject. This chapter describes situations in which visitor-associated infection transmission occurred and highlights the potential role of visitors in the transmission of pathogenic organisms that can lead to outbreaks in healthcare settings. Infection prevention measures, including isolation precautions and visitor restriction, may be utilized and potentially adapted in order to protect patients and their visitors as well as healthcare personnel. The practical and ethical challenges regarding the use of isolation precautions among visitors to healthcare facilities are discussed.

Immunization of Health-Care Providers: Necessity and Public Health Policies

Health-care providers (HCPs) are at increased risk for exposure to vaccine-preventable diseases (VPDs) in the workplace. The rationale for immunization of HCPs relies on the need to protect them and, indirectly, their patients from health-care-associated VPDs. Published evidence indicates significant immunity gaps for VPDs of HCPs globally. Deficits in knowledge and false perceptions about VPDs and vaccines are the most common barriers for vaccine uptake and may also influence communication about vaccines between HCPs and their patients. Most countries have immunization recommendations for HCPs; however, there are no universal policies and significant heterogeneity exists between countries in terms of vaccines, schedules, frame of implementation (recommendation or mandatory), and target categories of HCPs. Mandatory influenza immunization policies for HCPs have been implemented with high vaccine uptake rates. Stronger recommendations for HCP immunization and commitment at the level of the health-care facility are critical in order to achieve high vaccine coverage rates. Given the importance to health, mandatory immunization policies for VPDs that can cause serious morbidity and mortality to vulnerable patients should be considered.

Influenza Vaccination of Healthcare Workers in the United States, 1989-2002

Objectives.

We sought to estimate influenza vaccination coverage among healthcare workers (HCWs) in the United States during 1989-2002 and to identify factors associated with vaccination in this group. The Advisory Committee on Immunization Practices (ACIP) recommends annual influenza vaccination for HCWs to reduce transmission of influenza to patients at high risk for serious complications of influenza.

Design.

Analysis of cross-sectional data from 1989-2002 surveys conducted by the National Health Interview Survey (NHIS). The outcome measure was self-reported influenza vaccination in the past 12 months. Bivariate and multivariate analysis of 2002 NHIS data.

Setting.

Household interviews conducted during 1989-2002, weighted to reflect the noninstitutionalized, civilian US population.

Participants.

Adults aged 18 years or older participated in the study. A total of 2,089 were employed in healthcare occupations or settings in 2002, and 17,160 were employed in nonhealthcare occupations or settings.

Results.

The influenza vaccination rate among US HCWs increased from 10.0% in 1989 to 38.4% in 2002, with no significant change since 1997. In a multivariate model that included data from the 2002 NHIS, factors associated with a higher rate of influenza vaccination among HCWs aged 18-64 years included age of 50 years or older (odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.1), hospital employee status (OR, 1.5; 95% CI, 1.2-1.9), 1 or more visits to the office of a healthcare professional in the past 12 months (OR, 1.5; 95% CI, 1.1-2.2), receipt of employer-provided health insurance (OR, 1.5; 95% CI, 1.1-2.1), a history of pneumococcal vaccination (OR, 3.9; 95% CI, 2.5-6.1), and history of hepatitis B vaccination (OR, 1.9; 95% CI, 1.4-2.4). Non-Hispanic black persons were less likely to be vaccinated (OR, 0.6; 95% CI, 0.5-0.9) than non-Hispanic white persons. There were no significant differences in vaccination levels according to HCW occupation category.

Conclusions.

Influenza immunization among HCWs reached a plateau during 1997-2002. New strategies are needed to encourage US HCWs to receive influenza vaccination to prevent influenza illness in themselves and transmission of influenza to vulnerable patients.

Influenza Vaccination of Healthcare Workers and Vaccine Allocation for Healthcare Workers During Vaccine Shortages

Influenza causes substantial morbidity and mortality annually, particularly in high-risk groups such as the elderly, young children, immunosuppressed individuals, and individuals with chronic illnesses. Healthcare-associated transmission of influenza contributes to this burden but is often under-recognized except in the setting of large outbreaks. The Centers for Disease Control and Prevention has recommended annual influenza vaccination for healthcare workers (HCWs) with direct patient contact since 1984 and for all HCWs since 1993. The rationale for these recommendations is to reduce the chance that HCWs serve as vectors for healthcare-associated influenza due to their close contact with high-risk patients and to enhance both HCW and patient safety. Despite these recommendations as well as the effectiveness of interventions designed to increase HCW vaccination rates, the percentage of HCWs vaccinated annually remains unacceptably low. Ironically, at the same time that campaigns have sought to increase HCW vaccination rates, vaccine shortages, such as the shortage during the 2004-2005 influenza season, present challenges regarding allocation of available vaccine supplies to both patients and HCWs. This two-part document outlines the position of the Society for Healthcare Epidemiology of America on influenza vaccination for HCWs and provides guidance for the allocation of influenza vaccine to HCWs during a vaccine shortage based on influenza transmission routes and the essential need for a practical and adaptive strategy for allocation. These recommendations apply to all types of healthcare facilities, including acute care hospitals, long-term-care facilities, and ambulatory care settings.

Potential Ceiling Effect of Healthcare Worker Influenza Vaccination on the Incidence of Nosocomial Influenza Infection

OBJECTIVE To evaluate the effect of healthcare worker (HCW) influenza vaccination on the incidence of nosocomial influenza DESIGN Retrospective cross-sectional study SETTING A 550-bed tertiary-care academic medical center METHODS All admitted patients with a direct fluorescent antibody (DFA) or polymerase chain reaction (PCR) assay positive for influenza ordered between October 1 and May 31 from 2010 to 2015 were eligible for inclusion. Nosocomial influenza was defined as a positive influenza test collected ≥48 hours after admission in patients without influenza-like illness present within 24 hours of admission. Relative nosocomial influenza frequency was calculated by dividing the number of nosocomial cases by the total number of admitted patients with influenza for each season. A univariate logistic regression was used to determine the association between HCW influenza vaccination coverage and nosocomial influenza. RESULTS Over 5 seasons, 533 patients had positive influenza tests during their hospitalization; 29 of these patients (5.4%) acquired influenza during their hospitalization. HCW vaccination coverage increased over the 5 seasons from 47% to 90% (P<.001). Despite an initial decrease in relative nosocomial influenza frequency during the first year (9% to 4.9%), subsequent seasons failed to show an additional decrease in nosocomial infections (4.3%, 5.2%, and 4.8%, respectively); the overall decrease in nosocomial influenza from the first season to the final season was not significant (P=.282). No association was detected between HCW vaccination coverage and nosocomial influenza (odds ratio [OR], 0.990; 95% confidence interval [CI], 0.970-1.011). CONCLUSION HCW vaccination >50% may not have a significant effect on nosocomial influenza. Infect Control Hosp Epidemiol 2016;37:840-844.

Should professionals caring for children be vaccinated? Community perspectives on health care and child care worker immunisation

OBJECTIVE

Several immunisations including influenza and pertussis are specifically recommended for healthcare workers (HCW) and childcare workers (CCW). This study aimed to assess community attitudes to HCW and CCW immunisation recommendations for pertussis and seasonal influenza.

METHODS

A cross-sectional study was conducted by Computer Assisted Telephone Interviewing (CATI) from April to May 2011. Statistical analyses used data weighted to the South Australian population by probability of selection, age, gender and geographical location using benchmarks derived from the 2009 Census population figures.

RESULTS

Almost all respondents supported vaccination of HCWs and CCWs against pertussis and influenza. For pertussis, 95.3% agreed nurses, 94.9% agreed doctors and 94.7% agreed CCWs have an obligation to be vaccinated. For influenza, 91.4% agreed nurses, 90.7% agreed doctors and 89.9% agreed CCWs have an obligation to be vaccinated. We identified higher support for protection against pertussis compared to influenza for all three groups of workers (p<0.001). There were higher concerns if CCWs compared to HCWs were not vaccinated against pertussis (OR=2.78) and influenza (OR=1.99). Young (18-30 years) and older age (60+ years) and lower educational attainment were predictors of support for HCWs and CCWs to be vaccinated against influenza. For pertussis, lower educational attainment was a predictor of support for HCWs immunisation.

CONCLUSIONS

Community support for CCW and HCW immunisation is strong with CCW immunisation was considered a priority. Pertussis immunisation was considered a higher priority than influenza immunisation for HCWs and CCWs. CCW immunisation should be considered for inclusion in public health immunisation programmes.

Comparative acceptance of pertussis and influenza immunization among health-care personnel

BACKGROUND

Pertussis and influenza immunization in health-care professionals (HCP) has been shown to lead to significant reduction of nosocomial infections. Parallel campaigns of pertussis and seasonal influenza immunization gave us a unique opportunity to compare attitudes towards influenza and pertussis immunization among HCP and to determine acceptance rates for both or either one of the two immunizations or refusal of both.

METHODS

A questionnaire was sent to HCP to anonymously obtain demographic data, profession, numbers of previous influenza immunizations, acceptance of influenza immunization in the current 2012/13 season, pertussis immunization currently or within the last 10 years, and reasons for acceptance or decline of pertussis and influenza vaccination.

RESULTS

Of 638 HCP with patient contact, 314 (49%) responded and 303 (47%) were included in the analysis. Immunization acceptance rates were 33% for influenza, 57% for pertussis; 24% accepted both immunizations and 34% none of both. Acceptance of influenza immunization was significantly higher in those with one or more previous influenza vaccinations (p<0.005). Among 130 HCP who declined pertussis immunization, missed opportunity (28%) was the dominant reason. Of 204 HCP who declined influenza immunization, the most frequently stated reason was "lack of influenza immunization is not considered an issue" (36%).

CONCLUSIONS

Misconceptions about the efficacy and necessity of pertussis and especially influenza immunization continue to prevail among HCP. Active promotion, personal encouragement, providing more immunization opportunities and other incentives are measures that should be considered to increase the rate of immunization among HCP.

Influenza among afebrile and vaccinated healthcare workers

Background. To prevent transmission of influenza from healthcare workers (HCWs) to patients, many hospitals exclude febrile HCWs from working, but allow afebrile HCWs with respiratory symptoms to have contact with patients. During the 2013–2014 influenza season at our hospital, an influenza-positive HCW with respiratory symptoms but no fever was linked to a case of possible healthcare-associated influenza in a patient. Therefore, we implemented a temporary policy of mandatory influenza testing for HCWs with respiratory symptoms.

Methods. From 3 January through 28 February 2014, we tested HCWs with respiratory symptoms for influenza and other respiratory pathogens by polymerase chain reaction of flocked nasopharyngeal swabs. HCWs also reported symptoms and influenza vaccination status, and underwent temperature measurement. We calculated the proportion of influenza-positive HCWs with fever and prior influenza vaccination.

Results. Of 449 HCWs, 243 (54%) had a positive test for any respiratory pathogen; 34 (7.6%) HCWs tested positive for influenza. An additional 7 HCWs were diagnosed with influenza by outside physicians. Twenty-one (51.2%) employees with influenza had fever. Among influenza-infected HCWs, 20 had previously received influenza vaccination, 18 had declined the vaccine, and 3 had unknown vaccination status. There was no significant difference in febrile disease among influenza-infected employees who had received the influenza vaccine and those who had not received the vaccine (45% vs 61%; P = .32).

Conclusions. Nearly half of HCWs with influenza were afebrile prior to their diagnosis. HCWs with respiratory symptoms but no fever may pose a risk of influenza transmission to patients and coworkers.

Influenza Vaccination Rates and Motivators Among Healthcare Worker Groups

Background.

The rate of influenza vaccination among healthcare workers (HCWs) is approximately 40%. Differences in vaccination rates among HCW groups and reasons for accepting or rejecting vaccination are poorly understood.

Objectives.

To determine vaccination rates and motivators among different HCW groups during the 2004-2005 influenza season.

Design.

Cross-sectional survey conducted between July 10 and September 30, 2005.

Setting.

Two tertiary care teaching hospitals in an urban center.

Participants.

Physicians, nurses, nursing aides, and other staff. Surveys were collected from 1,042 HCWs (response rate, 42%).

Results.

Sixty-nine percent of physicians (n = 282) and 63% of medical students (n = 145) were vaccinated, compared with 46% of nurses (n = 336), 42% of nursing aides (n = 135), and 29% of administrative personnel (n = 144). Physicians and medical students were significantly more likely to be vaccinated than all other groups (P < .0001). Pediatricians (84%) were more likely than internists (69%) and surgeons (43%) to be vaccinated (P < .0001). Among the HCWs who were vaccinated, 33.4% received the live attenuated influenza vaccine (LAIV) and 66.6% received trivalent inactivated influenza vaccine (TIV). Vaccinated HCWs were less likely than unvaccinated HCWs to report an influenza-like illness (P = .03). Vaccination with LAIV resulted in fewer episodes of influenza-like illness than did receiving no vaccine (P = .03). The most common reason for rejecting vaccination was a concern about availability. Understanding that HCWs may transmit the virus to patients correlated with vaccine acceptance (P = .0004).

Conclusions.

Significant differences in vaccination exist among physician specialties and employee groups, and there are inadequate vaccination rates among those with the greatest amount of patient contact, potentially providing a basis for group-specific interventions.

Healthcare providers as sources of vaccine-preventable diseases

Vaccine-preventable infectious diseases may be introduced into the healthcare setting and pose a serious risk to vulnerable populations including immunocompromised patients. Healthcare providers (HCPs) are exposed to these pathogens through their daily tasks and may serve as a reservoir for ongoing disease transmission in the healthcare setting. The primary method of protection from work-related infection risk is vaccination that protects not only an individual HCP from disease, but also subsequent patients in contact with that HCP. Individual HCPs and healthcare institutions must balance the ethical and professional responsibility to protect their patients from nosocomial transmission of preventable infections with HCP autonomy. This article reviews known cases of HCP-to-patient transmission of the most common vaccine-preventable infections encountered in the healthcare setting including hepatitis B virus, influenza virus, Bordetella pertussis, varicella-zoster virus, measles, mumps and rubella virus. The impact of HCP vaccination on patient care and current recommendations for HCP vaccination against vaccine-preventable infectious diseases are also reviewed.

Hospital-onset influenza hospitalizations--United States, 2010-2011

BACKGROUND

Seasonal influenza is responsible for more than 200,000 hospitalizations each year in the United States. Although hospital-onset (HO) influenza contributes to morbidity and mortality among these patients, little is known about its overall epidemiology.

OBJECTIVE

We describe patients with HO influenza in the United States during the 2010-2011 influenza season and compare them with community-onset (CO) cases to better understand factors associated with illness.

METHODS

We identified laboratory-confirmed, influenza-related hospitalizations using the Influenza Hospitalization Surveillance Network (FluSurv-NET), a network that conducts population-based surveillance in 16 states. CO cases had laboratory confirmation ≤ 3 days after hospital admission; HO cases had laboratory confirmation > 3 days after admission.

RESULTS

We identified 172 (2.8%) HO cases among a total of 6,171 influenza-positive hospitalizations. HO and CO cases did not differ by age (P = .22), sex (P = .29), or race (P = .25). Chronic medical conditions were more common in HO cases (89%) compared with CO cases (78%) (P < .01), and a greater proportion of HO cases (42%) than CO cases (17%) were admitted to the intensive care unit (P < .01). The median length of stay after influenza diagnosis of HO cases (7.5 days) was greater than that of CO cases (3 days) (P < .01).

CONCLUSION

HO cases had greater length of stay and were more likely to be admitted to the intensive care unit or die compared with CO cases. HO influenza may play a role in the clinical outcome of hospitalized patients, particularly among those with chronic medical conditions.

Vaccination policies for healthcare workers in Europe

Health-care workers (HCWs) are at increased risk for acquisition of vaccine-preventable diseases (VPDs) and vaccination is justified in order to protect them from occupational exposure and to prevent the spread of VPDs that pose a threat to susceptible patients. Review of European vaccination policies for HCWs revealed significant differences between countries in terms of recommended vaccines, implementation frame (mandatory or recommendation), target HCW groups and health-care settings. Further, the few published studies available identified indicate significant immunity gaps among HCWs against VPDs in Europe. In order to achieve higher vaccination coverage against VPDs stronger recommendations are needed. The issue of mandatory vaccination should be considered for diseases that can be transmitted to susceptible patients (influenza, measles, mumps, rubella, hepatitis B, pertussis, varicella). The acceptance of vaccinations and of mandatory vaccinations by HCWs is a challenge and appears to be VPD-specific.

Seroepidemiological study of influenza A (H1N1) pdm09 virus following the 2009-2010 wave in Shandong Province, China

INTRODUCTION

The aims of this study were to understand the geographic extent, risk factors, and attack rate of influenza A (H1N1) pdm09 virus (pH1N1) infection in Shandong Province China and to elucidate influencing factors.

METHODS

In January and March 2010, a cross-sectional seroprevalence survey of pH1N1 was carried out. Serum samples from 9022 participants in the survey were subjected to the hemagglutination inhibition assay.

RESULTS

Among the 9022 participants, the overall rate of seropositivity against pH1N1 was 22.6%. The weighted rate, adjusted for gender, age, and region, was estimated to be 18.7%. Among 8340 subjects who did not report previous vaccination, the rate was 16.7%, as compared to 50.9% among 682 subjects reporting previous vaccination (p < 0.001). Within the unvaccinated population, the rate of seropositivity among 16-24 and 6-15 y-old subjects was 31.8% and 29.9%, respectively, as compared to 9.6% among subjects aged ≥ 60 y (p < 0.001) and 23% in the 0-5 y age group (p < 0.001). Those aged 6-15 y and aged 16-24 y had higher odds of seropositivity than those aged 0-5 y (odds ratio 1.53 and 1.48, respectively).

CONCLUSIONS

These study findings help enhance our understanding of pH1N1 epidemiology and provide valuable information for the vaccination strategy for the influenza season.

Assessing parents' knowledge and attitudes towards seasonal influenza vaccination of children before and after a seasonal influenza vaccination effectiveness study in low-income urban and rural Kenya, 2010-2011

Background

Influenza vaccine is rarely used in Kenya, and little is known about attitudes towards the vaccine. From June-September 2010, free seasonal influenza vaccine was offered to children between 6 months and 10 years old in two Population-Based Infectious Disease Surveillance (PBIDS) sites. This survey assessed attitudes about influenza, uptake of the vaccine and experiences with childhood influenza vaccination.

Methods

We administered a questionnaire and held focus group discussions with parents of children of enrollment age in the two sites before and after first year of the vaccine campaign. For pre-vaccination focus group discussions, we randomly selected mothers and fathers who had an eligible child from the PBIDS database to participate. For the post-vaccination focus group discussions we stratified parents whose children were eligible for vaccination into fully vaccinated, partially vaccinated and non-vaccinated groups.

Results

Overall, 5284 and 5755 people completed pre and post-vaccination questionnaires, respectively, in Kibera and Lwak. From pre-vaccination questionnaire results, among parents who were planning on vaccinating their children, 2219 (77.6%) in Kibera and 1780 (89.6%) in Lwak said the main reason was to protect the children from seasonal influenza. In the pre-vaccination discussions, no parent had heard of the seasonal influenza vaccine. At the end of the vaccine campaign, of 18,652 eligible children, 5,817 (31.2%) were fully vaccinated, 2,073 (11.1%) were partially vaccinated and, 10,762 (57.7%) were not vaccinated. In focus group discussions, parents who declined vaccine were concerned about vaccine safety or believed seasonal influenza illness was not severe enough to warrant vaccination. Parents who declined the vaccine were mainly too busy [251(25%) in Kibera and 95 (10.5%) in Lwak], or their child was away during the vaccination period [199(19.8%) in Kibera; 94(10.4%) in Lwak].

Conclusion

If influenza vaccine were to be introduced more broadly in Kenya, effective health messaging will be needed on vaccine side effects and frequency and potential severity of influenza infection.

Prospects for molecular point-of-care diagnosis of lower respiratory infections at the hospital’s doorstep

Now that molecular assays have been simplified, they can be performed at the point of care (POC). As we aimed to evaluate POC detection of respiratory viruses, we have collected studies on the molecular detection of viruses in children and adults with a well-characterized diagnosis, made in hospital settings, of community-acquired acute bronchiolitis (AB) or pneumonia (CAP). We then present the epidemiological issues for each disease. The prevalence of 18 virus species and types was determined separately for each disease, virus by virus. Overall, the median detection rate of viruses was 90% (interquartile range [IQR]: 69.25–93.5%) and 71.8% (IQR: 69.25–74.25%) in children with AB and CAP, respectively, and 24.5% (IQR: 20–30%) in adults with CAP. The observations on the relationship between virological findings and severity of disease were conflicting in AB, while those for influenza-related CAP were significantly associated with high morbidity/mortality. There is evidence supporting the suggestion that molecular POC detection of targeted pathogens could optimize bed management in emergency departments, guide anti-infective therapies and prevent nosocomial outbreaks. However, further investigations are required to determine when the detection of a large panel of viruses should be processed in clinical practice.

Postexposure prophylaxis for influenza in pediatric wards oseltamivir or zanamivir after rapid antigen detection

BACKGROUND

Postexposure prophylaxis (PEP) using neuraminidase inhibitors against exposure to influenza virus has been well studied in household settings but not in nosocomial settings in pediatric wards.

METHODS

We used oseltamivir or zanamivir as PEP in our pediatric wards. All influenza cases were diagnosed by the influenza rapid diagnostic test.

RESULTS

Between 2003 and 2011, there were 20 nosocomial introductions of influenza (10 were A, 9 were B and 1 was undetermined). The index cases consisted of 17 inpatients, 2 parents and 1 medical staff member. The 17 inpatients had been admitted to the hospital for reasons other than infectious disease and they developed influenza after hospitalization. Among the 81 contacts, 28 (35%) were exposed to influenza A, and 52 (64%) were exposed to influenza B. The rate of secondary infection among contacts not given PEP was 29% (5/17), and the rate among contacts given PEP was significantly lower, 3% (2/63; P = 0.004). The 2 infected contacts who had been given PEP were both influenza B cases, and both had received oseltamivir. The contacts who received PEP within 24 hours (59), for influenza A (23) and those who received zanamivir (15) did not develop influenza. No adverse events were reported.

CONCLUSIONS

PEP using oseltamivir or zanamivir for unexpected occurrences of nosocomial influenza in pediatric wards is safe and effective. The influenza rapid diagnostic test that we used was helpful for detecting nosocomial influenza in children.

The impact of infection control upon hospital-acquired influenza and respiratory syncytial virus

BACKGROUND

Respiratory syncytial virus (RSV) and influenza are important pediatric community-acquired (CA) and hospital-acquired (HA) pathogens. The occurrence of pandemic (H1N1) 2009 influenza resulted in additional efforts to intensify infection control (IC) strategies. We detail the impact of IC strategies between 2003 and 2010 on influenza and RSV.

METHODS

We assessed the rates of CA infections per 100 admissions and HA infections per 1000 patient-days for both RSV and influenza at Children's Memorial Hospital during the winter seasons (September through May) 2003-2010. The season of 2009, however, was extended through June due to ongoing admissions as a result of pandemic (H1N1) 2009 influenza. IC strategies implemented in response to pandemic (H1N1) 2009 influenza are described. The transmission ratio (HA cases/CA cases) was determined and correlated with IC efforts.

RESULTS

Substantial season- to-season variability exists for CA RSV and CA influenza rates. The rates of HA RSV and HA influenza and the transmission ratios for these viruses remained unchanged in 2009-10 in comparison to the prior year (at 0.02 and 0.01, respectively) despite implementation of multiple IC strategies. In contrast, since 2005 an inverse association was noted between hand hygiene compliance and the transmission ratio of both RSV and influenza, with Spearman correlation coefficients of -0.84 (p = 0.051) and -0.89 (p = 0.008), respectively.

CONCLUSIONS

We observed that improvements in hand hygiene compliance correlated with less transmission of RSV and influenza in the hospital. The important role of hand hygiene in preventing transmission of RSV and influenza to hospitalized children should be emphasized.

Large epidemiological influenza a outbreak in a teaching hospital from guatemala city

Objective. To describe the characteristics and interventions to control a large epidemiological Influenza A Outbreak. Methods. During the months of February to April 2006, a large outbreak of Influenza A was detected, which affected Health Care Workers and hospitalized patients in a large teaching Hospital in Guatemala City. Interventions to interrupt transmission were implemented and included barrier methods (N95 masks, respiratory isolation measures, etc.) and enhanced hand hygiene, vaccination of healthy Health Care Workers (HCW), restrictions for patient visits. Results. From February to April 2006, 59 hospitalized patients diagnosed with Influenza A. 19 AIDS patients (mortality: 71%) and 5/40 (12.5%) in other diseases: cancer (3), severe cardiac failure (1) and severe malnutrition (1). The attack rate at day 20 in doctors and medical students was 21% while in other HCW it was 10.5%. Within 3 weeks of the beginning of the plan, deaths were stopped and no more cases in HCW were detected after 3 additional weeks. Conclusion. A rapid, comprehensive plan for the control of nosocomial epidemic Influenza A outbreaks is essential to limit severe morbidity and mortality in hospitals who attend large immunocompromised populations, including AIDS patients. HCW regular vaccinations programs are mandatory.

Should lower respiratory tract secretions from intensive care patients be systematically screened for influenza virus during the influenza season?

Introduction

Influenza is easily overlooked in intensive care units (ICUs), particularly in patients with alternative causes of respiratory failure or in those who acquire influenza during their ICU stay.

Methods

We performed a prospective study of patients admitted to three adult ICUs of our hospital from December 2010 to February 2011. All tracheal aspirate (TA) samples sent to the microbiology department were systematically screened for influenza. We defined influenza as unsuspected if testing was not requested and the patient was not receiving empirical antiviral therapy after sample collection.

Results

We received TA samples from 105 patients. Influenza was detected in 31 patients and was classified as unsuspected in 15 (48.4%) patients, and as hospital acquired in 13 (42%) patients. Suspected and unsuspected cases were compared, and significant differences were found for age (53 versus 69 median years), severe respiratory failure (68.8% versus 20%), surgery (6.3% versus 60%), median days of ICU stay before diagnosis (1 versus 4), nosocomial infection (18.8% versus 66.7%), cough (93.8% versus 53.3%), localized infiltrate on chest radiograph (6.3% versus 40%), median days to antiviral treatment (2 versus 9), pneumonia (93.8% versus 53.3%), and acute respiratory distress syndrome (75% versus 26.7%). Multivariate analysis showed admission to the surgical ICU (odds ratio (OR), 37.1; 95% confidence interval (CI), 2.1 to 666.6; P = 0.01) and localized infiltrate on chest radiograph (OR, 27.8; 95% CI, 1.3 to 584.1; P = 0.03) to be independent risk factors for unsuspected influenza. Overall mortality at 30 days was 29%. ICU admission for severe respiratory failure was an independent risk factor for poor outcome.

Conclusion

During the influenza season, almost one third of critical patients with suspected lower respiratory tract infection had influenza, and in 48.4%, the influenza was unsuspected. Lower respiratory samples from adult ICUs should be systematically screened for influenza during seasonal epidemics.

Epidemiology and clinical characteristics of parainfluenza virus 3 outbreak in a Haemato-oncology unit

OBJECTIVES

We describe molecular investigations of a large hospital outbreak of parainfluenza virus type 3 (PIV3), in which 32 patients became infected. We outline infection control measures that successfully limited further spread of PIV3 in a Haemato-oncology unit.

METHODS

Clinical retrospective review of infected haemato-oncology patients was undertaken. PIV3 haemagglutinin sequences from each case (n = 32) and local epidemiologically unlinked controls (n = 53) were compared to identify potential linkage.

RESULTS

PIV3-infected patients presented with upper (n = 18) and lower (n = 11) respiratory tract infections, 3 showed pyrexia only and one was asymptomatic. All symptomatic patients received antibiotics; bacterial co-infection was confirmed in eleven patients. PIV3 infections were associated with lower mortality than documented previously; three of the PIV3-infected patients died (3/32; 9%). All deaths were associated with relapsed malignancies, and PIV3 was not believed to be the primary cause of death in any of these patients. Sequences from 27 cases clustered closely together, consistent with nosocomial infections from PIV3 circulating within the ward. Factors favouring transmission were high patient turnaround between the day treatment unit and in-patient ward, and limited isolation facilities for immunocompromised and infected patients, especially within the day treatment unit. New infections reduced to baseline levels three days after enhanced infection control interventions were introduced.

CONCLUSIONS

Molecular epidemiological analysis provided evidence for nosocomial transmission of PIV3 infection that facilitated effective implementation of infection control measures. These were instrumental in restricting further spread of the virus among high-risk patients.

Influenza A/H1N1/2009 outbreak in a neonatal intensive care unit

BACKGROUND

Outbreaks of influenza A/H1N1/2009 in neonatal intensive care units (NICUs) have been reported only rarely. Annual vaccination of all healthcare workers (HCWs) against seasonal influenza is recommended but compliance is low and exposure to infected staff as the source of nosocomial outbreaks has been described.

AIM

To report an outbreak of influenza A/H1N1/2009 in a tertiary level NICU that resulted in considerable morbidity.

METHODS

When the first influenza case was identified, a prospective study was conducted and control measures were implemented to reduce the spread of infection throughout the NICU. Neonates who developed influenza were treated with oseltamivir, and exposed neonates were given prophylaxis with oseltamivir.

FINDINGS

Two infected infants who were immature by gestational age and birth weight developed pneumonitis requiring respiratory support, and a third full-term neonate had a mild uncomplicated illness. No significant adverse effects were noted during antiviral treatment or prophylaxis. The investigation identified infected HCWs as the likely source of the outbreak. There was a very low influenza vaccination rate of 15% among nursing staff.

CONCLUSION

Nosocomial influenza can cause considerable morbidity, especially in high risk neonates, and is readily transmissible in the NICU setting by unvaccinated staff members who contract influenza. To prevent outbreaks, in addition to infection control measures, the implementation of HCW vaccination is very important. Oseltamivir treatment was well-tolerated even among premature infants and appeared to be effective, because neonates with influenza had complete recovery and only one of those who received prophylaxis developed the infection.

Extremely low risk for acquisition of a respiratory viral infection in the emergency room of a large pediatric hospital during the winter season

Please cite this paper as: Maltezou et al. (2012). Extremely low risk for acquisition of a respiratory viral infection in the emergency room of a large pediatric hospital during the winter season. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00355.x.

The aim of this study was to investigate the rate of transmission of respiratory viral infections to children visiting the emergency room of a large pediatric hospital during winter. A total of 615 children were prospectively studied. Twenty‐two (3·6%) children developed at least one symptom compatible with a respiratory viral infection within 1–7 days after the visit, including cough (12 children), fever (8), rhinorrhea (7), and/or respiratory distress (1). Three children (0·49%) developed an influenza‐like illness. These findings indicate that transmission of respiratory viral infections to children visiting an emergency room during the winter season is extremely low.

Nosocomial pandemic (H1N1) 2009, United Kingdom, 2009-2010

To determine clinical characteristics of patients hospitalized in the United Kingdom with pandemic (H1N1) 2009, we studied 1,520 patients in 75 National Health Service hospitals. We characterized patients who acquired influenza nosocomially during the pandemic (H1N1) 2009 outbreak. Of 30 patients, 12 (80%) of 15 adults and 14 (93%) of 15 children had serious underlying illnesses. Only 12 (57%) of 21 patients who received antiviral therapy did so within 48 hours after symptom onset, but 53% needed escalated care or mechanical ventilation; 8 (27%) of 30 died. Despite national guidelines and standardized infection control procedures, nosocomial transmission remains a problem when influenza is prevalent. Health care workers should be routinely offered influenza vaccine, and vaccination should be prioritized for all patients at high risk. Staff should remain alert to the possibility of influenza in patients with complex clinical problems and be ready to institute antiviral therapy while awaiting diagnosis during influenza outbreaks.

Seroepidemiological study of pandemic influenza H1N1 following the 2009-2010 wave in Greece

Knowledge of seroprevalence rates against 2009 pandemic H1N1 virus will assist vaccination recommendations and the preparation of the health-care system during subsequent years. This study was conducted in Greece during June-August 2010 to estimate the seroprevalence rate against pandemic H1N1 virus. Persons presenting in 29 health-care facilities across the country were studied. Seroprevalence was estimated employing a virus-free ELISA that specifically recognizes 2009 H1N1 virus antibodies in human sera. Sera collected from 2005 to April 2009 were also used to estimate pre-pandemic seroprevalence rates. A total of 954 persons were studied. The overall seroprevalence rate was 28.5% (95% confidence interval=25.6-31.3%). Age-specific rates were 34.2% in persons 0-4 years, 36.3% in persons 5-19 years, 25.0% in persons 20-39 years, 23.4% in persons 40-59 years, and 31.8% in persons ≥ 60 years. The highest rates were recorded in the Regions of Ionian Islands (67%) and Epirus (42.9%), while the lowest (8.4%) in the Region of Thessaly. Age-specific attack rates of infection during 2009-2010 were 28.8% in persons 0-4 years, 32.5% in persons 5-19 years, 14.3% in persons 20-39 years, 19.1% in persons 40-59 years, and 14.4% in persons ≥ 60 years. Multivariate analysis revealed that Region of residence and caring for children <5 years were associated with increased risk for seropositivity. Urbanity, personal and family characteristics, working in a health-care facility or in a school, history of pandemic H1N1 vaccination or history of influenza-like illness during 2009-2010 were not associated with increased risk for seropositivity.

Severe cases of pandemic (H1N1) 2009 in children, Germany

In a hospital-based observational study in Germany, we investigated children admitted to pediatric intensive care units and deaths caused by confirmed pandemic (H1N1) 2009 to identify risk factors and outcomes in critically ill children. Ninety-three children were eligible for our study, including 9 with hospital-acquired infections. Seventy-five percent had underlying chronic medical conditions; neurodevelopmental disorders were most prevalent (57%). The proportion of patients having >1 risk factor increased with age in years (odds ratio 1.21, p = 0.007). Of 15 deaths, 11 occurred in a pediatric intensive care unit (case-fatality rate 12%, 95% confidence interval 6%–21%). Only 9% of the children had been vaccinated against pandemic (H1N1) 2009; all survived. Our results stress the role of underlying risk factors, especially neurodevelopmental disorders, and the need for improving preventive measures to reduce severe disease and adverse outcomes of pandemic (H1N1) 2009 in children.

Nosocomial transmission of parainfluenza 3 virus in hematological patients characterized by molecular epidemiology

We report an outbreak of parainfluenza 3 virus involving 17 hematology-oncology patients on 2 hospital wards. Sequence analysis of clinical samples confirmed homology of strains for 16/17 patients and 1 healthcare worker. Epidemiological analysis of the outbreak supported the molecular data with nosocomial transmission of the same genetic strain as the cause of the outbreak.

Vaccination of health-care workers against influenza: our obligation to protect patients

Please cite this paper as: Maltezou and Tsakris. (2011) Vaccination of health‐care workers against influenza: our obligation to protect patients. Influenza and Other Respiratory Viruses 5(6), 382–388.

Nosocomial influenza poses a threat for specific groups of patients and is associated not only with the disruption of health‐care services but also excess costs. Although vaccination of health‐care workers (HCWs) has been recommended for almost three decades and constitutes the most convenient and effective means to prevent nosocomial transmission, vaccine uptake within this group remains unacceptably low worldwide. In regard to the pandemic influenza A H1N1, HCWs constitute a priority group for immunization. Nevertheless, low vaccination rates have been documented regarding the influenza pandemic and associated with the onset of nosocomial cases and outbreaks. HCWs, health‐care institutions, and public health bodies have the moral obligation to protect vulnerable patients and therefore weigh the benefits of mandatory vaccination. Key effective interventions, such as the education of HCWs concerning the benefits and safety of influenza vaccination, the reinforcement of on‐site, free of charge vaccinations, and the use of mobile vaccination teams in conjunction with incentives, should be widely implemented.

Are Kenyan healthcare workers willing to receive the pandemic influenza vaccine? Results from a cross-sectional survey of healthcare workers in Kenya about knowledge, attitudes and practices concerning infection with and vaccination against 2009 pandemic influenza A (H1N1), 2010

Over 1200 cases of 2009 pandemic influenza A H1N1 (pH1N1) have been identified in Kenya since the first case in June 2009. In April 2010 the Kenyan government launched a program to immunize high-risk groups and healthcare workers (HCWs) with pH1N1 vaccines donated by the World Health Organization. To characterize HCWs' knowledge, attitudes and practices regarding pH1N1 vaccination, we conducted a quantitative and qualitative survey in 20 healthcare facilities across Kenya between January 11 and 26, 2010. Of 659 HCWs interviewed, 55% thought there was a vaccine against pH1N1, and 89% indicated that they would receive pH1N1 vaccine if it became available. In focus group discussions, many HCWs said that pH1N1 virus infection did not cause severe disease in Kenyans and questioned the need for vaccination. However, most were willing to accept vaccination if they had adequate information on safety and efficacy. In order for the influenza vaccination campaign to be successful, HCWs must understand that pH1N1 can cause severe disease in Kenyans, that pH1N1 vaccination can prevent HCWs from transmitting influenza to their patients, and that the vaccine has been widely used globally with few recognized adverse events.

Hospital epidemiology and infection control in acute-care settings

Health care-associated infections (HAIs) have become more common as medical care has grown more complex and patients have become more complicated. HAIs are associated with significant morbidity, mortality, and cost. Growing rates of HAIs alongside evidence suggesting that active surveillance and infection control practices can prevent HAIs led to the development of hospital epidemiology and infection control programs. The role for infection control programs has grown and continues to grow as rates of antimicrobial resistance rise and HAIs lead to increasing risks to patients and expanding health care costs. In this review, we summarize the history of the development of hospital epidemiology and infection control, common HAIs and the pathogens causing them, and the structure and role of a hospital epidemiology and infection control program.

Reflections on the influenza vaccination of healthcare workers

Despite all that is known about the dangers of nosocomial transmission of influenza to the vulnerable patient populations in our healthcare facilities, and the benefits of the influenza vaccination, the low rates of influenza vaccination among healthcare workers (HCWs) internationally shows no sign of significant improvement. With the current voluntary 'opt-in' programmes clearly failing to adequately address this issue, the time has undoubtedly come for a new approach to vaccination to be implemented. Two different approaches to vaccination delivery have been suggested to rectify this situation, mandatory vaccination and 'opt-out' declination forms. It is suggested, however, that these two approaches are inadequate when used by themselves. In order to protect the most vulnerable patients in our healthcare facilities as best we can from serious harm or death caused by nosocomial transmission of influenza, while at the same time respecting HCWs autonomy, and in many jurisdictions, the related legal right to refuse medical treatment, it is recommended that 'op-out' declination forms should be used in conjunction with restricted mandatory vaccination. This 'combined' approach would allow any HCW to refuse the influenza vaccination, but would make the influenza vaccination a mandatory requirement for working in areas where the most vulnerable patients are cared for. Those HCWs not willing to be vaccinated should be required to work in other areas of healthcare.