Nosocomial pertussis in neonatal units

Diphtheria, tetanus, and pertussis immunity among healthcare professionals and pregnant women in the Moscow region, Russian federation: A preliminary cross-sectional study

Despite more than 50 years of primary immunization against diphtheria, pertussis, and tetanus in Russia, complicated illnesses, including fatal ones, still occur. The goal of this preliminary cross-sectional study is to see how well pregnant women and healthcare workers are protected against diphtheria, pertussis, and tetanus. The required sample size (pregnant women and healthcare professionals, as well as pregnant women of two age categories) for this preliminary cross-sectional study was calculated using a confidence value of 0.95 and a probability of 0.05. The required number of participants in each group calculated sample size must be at least 59 people. In the Moscow region (Solnechnogorsk city, Russia), a cross-sectional study of pregnant patients and healthcare professionals interacting with children regularly as part of their job from numerous medical organizations was conducted in the year 2021 (n = 655). Antibodies to diphtheria, tetanus, and pertussis toxoids and microorganisms were measured using an enzyme-linked immunosorbent assay (ELISA). The STATISTICA and IBM SPSS Statistics 26.0 were used to process the study results statistically. Descriptive statistics methods, the Mann-Whitney U-test, discriminant analysis with the stepwise selection and analysis of ROC-curves were applied. IgG against diphtheria was found in 99.5% of pregnant women, tetanus in 91.5%, and pertussis in only 36.5%. According to the results of the discriminant analysis, the value of IgG to pertussis is linked to the value of IgA to pertussis and the gestational periods. Immunity to diphtheria was discovered in 99.1% of medical personnel, tetanus in 96.9%, and pertussis in 43.9%, no significant variations with age. When comparing the levels of immunity of pregnant women and healthcare professionals, it was shown that healthcare workers have greater levels of immunity against diphtheria and tetanus. The novel contribution of this study is that it will reveal the proportion of those vulnerable to pertussis, diphtheria, and tetanus among health workers and pregnant women in all age groups under the current national immunization program in Russia. Considering the data obtained from the preliminary cross-sectional study, we believe that it is necessary to conduct a full-scale study on a larger sample and, based on that, make certain changes to the national immunization program in Russia.

Vaccination policies for healthcare personnel: Current challenges and future perspectives

Healthcare personnel (HCP) are at occupational risk for acquisition of several vaccine-preventable diseases and transmission to patients. Vaccinations of HCP are justified to confer them immunity but also to protect susceptible patients and healthcare services from outbreaks, HCP absenteeism and presenteeism. Mandatory vaccination policies for HCP are increasingly adopted and achieve high and sustainable vaccination rates in short term. In this article we review the scientific evidence for HCP vaccination. We also address issues pertaining to vaccination policies for HCP and present the challenges of implementation of mandatory versus voluntary vaccination policies. Finally, we discuss the issue of mandatory vaccination of HCP against COVID-19.

Vaccination coverage rates and attitudes towards mandatory vaccinations among healthcare personnel in tertiary-care hospitals in Greece

OBJECTIVES

: Our aim was to estimate vaccination and susceptibility rates against vaccine-preventable diseases among healthcare personnel (HCP) in eight hospitals.

METHODS

This study was a cross-sectional survey.

RESULTS

A total of 1284 HCP participated (physicians: 31.3%, nursing personnel: 36.6%, paramedical personnel: 11.1%, administrative personnel: 13.2%, supportive personnel: 7.3%). Vaccination rates were 32.9% against measles and mumps, 38.1% against rubella, 5.7% against varicella, 9.2% against hepatitis A, 65.8% against hepatitis B, 31.8% against tetanus-diphtheria, 7.1% against pertussis, 60.2% against influenza, and 80.1% against COVID-19. Susceptibility rates were: 27.8% for measles, 39.6% for mumps, 33.4% for rubella, 22.2% for varicella, 86.3% for hepatitis A, 34.2% for hepatitis B, 68.2% for tetanus-diphtheria, and 92.9% for pertussis. Older HCP had higher susceptibility rates against mumps, rubella, varicella, hepatitis A, hepatitis B, tetanus-diphtheria, and pertussis (p-values <0.001 for all). Mandatory vaccinations were supported by 81.85% of HCP.

CONCLUSIONS

Although most HCP supported mandatory vaccinations, significant vaccination gaps and susceptibility rates were recorded. The proportion of susceptible HCP to measles, mumps, rubella, and varicella increased the past decade, mostly because of reduction of acquired cases of natural illness. Vaccination programs for HCP should be developed. A national registry to follow HCP' vaccination rates is urgently needed.

Outbreaks in Health Care Settings

Outbreaks and pseudo-outbreaks in health care settings are complex and should be evaluated systematically using epidemiologic and molecular tools. Outbreaks result from failures of infection prevention practices, inadequate staffing, and undertrained or overcommitted health care personnel. Contaminated hands, equipment, supplies, water, ventilation systems, and environment may also contribute. Neonatal intensive care, endoscopy, oncology, and transplant units are areas at particular risk. Procedures, such as bronchoscopy and endoscopy, are sources of infection when cleaning and disinfection processes are inadequate. New types of equipment can be introduced and lead to contamination or equipment and medications can be contaminated at the manufacturing source.

Immunity to vaccine-preventable diseases among paediatric healthcare workers in Denmark, 2019

Background

Healthcare workers (HCW) have been identified as index cases in disease outbreaks of vaccine-preventable diseases (VPD) in hospitals.

Aim

We investigated whether Danish paediatric HCW were protected against selected serious VPD.

Methods

We included 90% of staff members from two paediatric departments. All 555 HCW (496 women) supplied a blood sample for serology and filled in a questionnaire. Antibodies were measured with enzyme immunoassay against measles, mumps, rubella (MMR), varicella zoster, pertussis toxin and diphtheria toxin.

Results

Protective levels of IgG were found for measles (90.3%), mumps (86.5%), rubella (92.3%), varicella (98.6%) and diphtheria (80.5%). We found seropositivity for all three MMR components in 421 (75.9%) HCW, lowest in those younger than 36 years (63.3%). Only 28 (5%) HCW had measurable IgG to pertussis. HCW with self-reported immunity defined as previous infection or vaccination, had protective levels of IgG against measles, mumps, rubella and varicella in 87.4–98.8% of cases, not significantly higher than in those not reporting immunity. Previous history of disease had a high positive predictive value (PPV) of 96.8–98.8%. The PPV for previous vaccination ranged from 82.5% to 90.3%. In contrast, negative predictive values of self-reported history of disease and vaccination were remarkably low for all diseases.

Conclusion

The immunity gaps found primarily in young HCW indicate a need for a screening and vaccination strategy for this group. Considering the poor correlation between self-reported immunity and seropositivity, efforts should be made to check HCW’s immune status in order to identify those who would benefit from vaccination.

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.

Vaccination of healthcare personnel in Europe: Update to current policies

We investigated and compared current national vaccination policies for health-care personnel (HCP) in Europe with results from our previous survey. Data from 36 European countries were collected using the same methodology as in 2011. National policies for HCP immunization were in place in all countries. There were significant differences in terms of number of vaccinations, target HCP and healthcare settings, and implementation regulations (recommended or mandatory vaccinations). Vaccination policies against hepatitis B and seasonal influenza were present in 35 countries each. Policies for vaccination of HCP against measles, mumps, rubella and varicella existed in 28, 24, 25 and 19 countries, respectively; and against tetanus, diphtheria, pertussis and poliomyelitis in 21, 20, 19, and 18 countries, respectively. Recommendations for hepatitis A immunization existed in 17 countries, and against meningococcus B, meningococcus C, meningococcus A, C, W, Y, and tuberculosis in 10, 8, 17, and 7 countries, respectively. Mandatory vaccination policies were found in 13 countries and were a pre-requisite for employment in ten. Comparing the vaccination programs of the 30 European countries that participated in the 2011 survey, we found that more countries had national vaccination policies against measles, mumps, rubella, hepatitis A, diphtheria, tetanus, poliomyelitis, pertussis, meningococcus C and/or meningococcus A, C, W, Y; and more of these implemented mandatory vaccination policies for HCP. In conclusion, European countries now have more comprehensive national vaccination programs for HCP, however there are still gaps. Given the recent large outbreaks of vaccine-preventable diseases in Europe and the occupational risk for HCP, vaccination policies need to be expanded and strengthened in several European countries. Overall, vaccination policies for HCP in Europe should be periodically re-evaluated in order to provide optimal protection against vaccine-preventable diseases and infection control within healthcare facilities for HCP and patients.

Vaccines for Health Care Personnel

Medical Center Occupational Health (MCOH) programs must protect health care personnel (HCP) against the occupational risk of vaccine-preventable diseases. This thematic review outlines the rationale for the use of recommended vaccines in HCP; summarizes the available evidence regarding vaccine effectiveness, administration, and assessment of immunity; and provides guidance for MCOH programs navigating challenging situations.

Do previously held vaccine attitudes dictate the extent and influence of vaccine information-seeking behavior during pregnancy?

Pregnancy represents a high information need state, where uncertainty around medical intervention is common. As such, the pertussis vaccination given during pregnancy presents a unique opportunity to study the interaction between vaccine attitudes and vaccine information-seeking behavior.

We surveyed a sample of pregnant women (N = 182) during early pregnancy and again during late pregnancy. The variables of vaccine confidence and risk perception of vaccination during pregnancy were measured across two questionnaires. Additional variables of decision conflict and intention to vaccinate were recorded during early pregnancy, while vaccine information-seeking behavior and vaccine uptake were recorded during late pregnancy.

88.8% of participants reported seeking additional information about the pertussis vaccine during pregnancy. Women that had a lower confidence in vaccination (p = .004) and those that saw the risk of pertussis disease as high compared to the risk of side effects from the pertussis vaccination during pregnancy (p = .004) spent significantly more time seeking information about the pertussis vaccination.

Women’s perception of risk related to vaccination during pregnancy significantly changed throughout the pregnancy (t(182) = 4.685 p< .001), with women perceiving the risk of pertussis disease higher as compared to the risk of side effects from the vaccine as the pregnancy progresses.

The strength and influence of information found through seeking was predicted by intention to vaccinate (p = .011). As such, we suggest that intention to vaccinate during early pregnancy plays a role in whether the information found through seeking influences women towards or away from vaccination.

Vaccine-preventable diseases and vaccination among Italian healthcare workers: a review of current literature

Protection of healthcare workers (HCWs) from biological hazards in the workplace has the added benefit of contributing to the quality of patient care and patient safety. Vaccinated HCWs act as a barrier against the spread of infections and maintain essential healthcare delivery during outbreaks. In Italy, specific recommendations for vaccination of HCWs are issued by the Ministry of Health within the framework of the National Immunization Prevention Plan. These recommendations provide advice regarding HCW vaccination for hepatitis B, influenza, pertussis, measles, mumps, rubella, varicella and tuberculosis. This paper summarizes the current literature on vaccine-preventable diseases and vaccination among Italian HCWs.

Systematic review found that there was moderate evidence that vaccinating healthcare workers prevented pertussis in infants

This systematic review investigated the effectiveness of vaccinating healthcare workers against pertussis on the occurrence of nosocomial pertussis outbreaks or infections among unprotected infants. We focused on eight studies, with five different study designs, that involved 39,129 healthy adolescents and adults, 115 healthcare workers, 2000 simulated healthcare workers and a simulated population of 200,000 people.

CONCLUSION

There was moderate evidence that tetanus-diphtheria acellular pertussis vaccinations for healthcare workers were effective in preventing pertussis in all age groups and specifically in infants. The results must be interpreted with caution due to the low quality and heterogeneity of the studies.

Healthcare-associated infections: potential for prevention through vaccination

The challenge of healthcare-associated infections is compounded by the higher incidence of resistant organisms and the decreasing utility of antimicrobial agents. Historic and current vaccines have already contributed to reductions in healthcare-associated infections, and future vaccines have the potential to reduce these infections further. Through examples of bacterial and viral vaccines, this review will attempt to chart the way forward.

Les vaccins dans la prévention des infections associées aux soins

Les infections associées aux soins (IAS) constituent un véritable problème de santé publique. Escherichia coli, Staphylococcus aureus, Clostridium difficile sont les plus souvent à l’origine des IAS. L’antibiorésistance fréquente complique encore la prise en charge et des impasses thérapeutiques existent à présent. Les mesures d’hygiène hospitalière bien qu’essentielles sont insuffisantes pour diminuer drastiquement les IAS. Ainsi, des stratégies alternatives à l’antibiothérapie s’avèrent nécessaires pour prévenir et traiter les IAS. Parmi celles-ci, la vaccination et l’immunisation passive sont probablement les plus prometteuses. Nous avons fait une mise au point sur les vaccins disponibles et en développement clinique pour lutter contre les IAS, chez les patients à risque d’IAS et les soignants. L’intérêt de la vaccination grippale et rotavirus chez les patients pour prévenir ces IAS virales a été examiné. Le développement d’un vaccin anti-S. aureus, déjà émaillé de 2 échecs est complexe. Toutefois, ces échecs ont permis d’améliorer les connaissances sur l’immunité anti-S. aureus. La mise à disposition d’un vaccin préventif anti-C. difficile semble plus proche. Pour les autres bactéries gram négatif responsables d’IAS, le développement est moins avancé. La vaccination des patients à risques d’IAS pose également des problèmes de réponse vaccinale qu’il faudra résoudre pour utiliser cette stratégie. Ainsi, la vaccination des soignants, de par l’effet de groupe permet également de prévenir les IAS. Nous faisons ici le point sur l’intérêt de la vaccination des soignants contre la rougeole, la coqueluche, la grippe, la varicelle, l’hépatite B pour réduire les IAS avec des vaccins déjà disponibles.

Tdap Vaccination Among Healthcare Personnel, Internet Panel Survey, 2012-2014

INTRODUCTION

Healthcare personnel (HCP) are at risk for pertussis infection exposure or transmitting the disease to patients in their work settings. The Advisory Committee on Immunization Practices recommends tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) vaccination for HCP to minimize these risks. This study assessed Tdap vaccination coverage among U.S. HCP by sociodemographic and occupation-related characteristics.

METHODS

The 2012, 2013, and 2014 Internet Panel Surveys were analyzed in 2015 to assess HCP Tdap vaccination. Effective sample sizes for 2012, 2013, and 2014 survey years were 2,038, 1613, and 1633, respectively. Missing values were assigned using multiple imputation. Multivariable logistic regression identified factors independently associated with HCP Tdap vaccination. Statistical measures were calculated with an assumption of random sampling.

RESULTS

Overall, Tdap vaccination coverage among HCP was 34.8% (95% CI=30.6%, 39.0%); 40.2% (95% CI=36.1%, 44.4%); and 42.4% (95% CI=38.7%, 46.0%) in 2012, 2013, and 2014, respectively. Nurse practitioners/physician's assistants, physicians, nurses, and HCP working in hospitals and ambulatory care settings had higher Tdap coverage. Having contact with an infant aged ≤6 months and influenza vaccination receipt were associated with increased Tdap vaccination. Non-Hispanic black race/ethnicity, having an associate/bachelor's degree, being below poverty, non-clinical personnel status, and working in a long-term care setting were associated with decreased Tdap vaccination.

CONCLUSIONS

HCP Tdap vaccination coverage increased during 2012-2014; however, coverage remains low. Vaccination coverage varied widely by healthcare occupation, occupational setting, and sociodemographic characteristics. Evidence-based employer strategies used to increase HCP influenza vaccination, if applied to Tdap, may increase Tdap coverage.

Lack of Pertussis Protective Antibodies in Healthcare Providers Taking Care of Neonates and Infants in a Children's Hospital

Contact tracing and seroepidemiologic studies were done after a premature baby contracted pertussis in a children's hospital. No infection source was confirmed. Four (3.5%) healthcare providers were positive for anti-pertussis IgM, while only 23% (26/113) were positive for IgG in a following survey. Pertussis vaccination for healthcare providers is needed.

Vaccination of healthcare workers: A review

Vaccine-preventable diseases are a significant cause of morbidity and mortality. As new vaccines are proving to be effective and as the incidence of some infections decreases, vaccination practices are changing. Healthcare workers (HCWs) are particularly exposed to and play a role in nosocomial transmission, which makes them an important target group for vaccination. Most vaccine-preventable diseases still carry a significant risk of resurgence and have caused outbreaks in recent years. While many professional societies favor vaccination of HCWs as well as the general population, recommendations differ from country to country. In turn, vaccination coverage varies widely for each microorganism and for each country, making hospitals and clinics vulnerable to outbreaks. Vaccine mandates and non-mandatory strategies are the subject of ongoing research and controversies. Optimal approaches to increase coverage and turn the healthcare workforce into an efficient barrier against infectious diseases are still being debated.

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.

Pertussis: Microbiology, Disease, Treatment, and Prevention

Pertussis is a severe respiratory infection caused by Bordetella pertussis, and in 2008, pertussis was associated with an estimated 16 million cases and 195,000 deaths globally. Sizeable outbreaks of pertussis have been reported over the past 5 years, and disease reemergence has been the focus of international attention to develop a deeper understanding of pathogen virulence and genetic evolution of B. pertussis strains. During the past 20 years, the scientific community has recognized pertussis among adults as well as infants and children. Increased recognition that older children and adolescents are at risk for disease and may transmit B. pertussis to younger siblings has underscored the need to better understand the role of innate, humoral, and cell-mediated immunity, including the role of waning immunity. Although recognition of adult pertussis has increased in tandem with a better understanding of B. pertussis pathogenesis, pertussis in neonates and adults can manifest with atypical clinical presentations. Such disease patterns make pertussis recognition difficult and lead to delays in treatment. Ongoing research using newer tools for molecular analysis holds promise for improved understanding of pertussis epidemiology, bacterial pathogenesis, bioinformatics, and immunology. Together, these advances provide a foundation for the development of new-generation diagnostics, therapeutics, and vaccines.

The pregnant healthcare worker: fact and fiction

PURPOSE OF REVIEW

A pregnant healthcare worker (HCW) may be at risk of occupational exposure to pathogens associated with increased maternal morbidity and mortality as well as perinatal complications. In this article, we review recent literature on infectious diseases commonly encountered in the healthcare setting and of highest concern for a pregnant HCW, focusing on prevention and management of exposures.

RECENT FINDINGS

Pregnancy does not seem to be an independent risk factor for occupationally acquired infectious diseases. Vaccination and standard precautions continue to be the most effective means of preventing transmission to HCWs. Pandemic 2009 influenza A (H1N1) is associated with increased risk of fetal death, highlighting the importance of influenza vaccination. A recent meta-analysis highlights the safety of influenza vaccination during pregnancy. New treatments for hepatitis C have not been studied in pregnancy but pose an important area for research and advancement. Cytomegalovirus immunoglobulin may play a role in postexposure prophylaxis but recent results are inconclusive.

SUMMARY

Primary prevention with vaccination and use of appropriate infection control precautions is imperative for prevention of occupationally acquired infectious diseases. Pregnant HCWs with occupational exposure to communicable diseases should be evaluated immediately for appropriate postexposure prophylaxis and followed for development of active infection.

Protecting Newborns Against Pertussis: Treatment and Prevention Strategies

Pertussis is a potentially severe respiratory disease, which affects all age groups from young infants to older adults and is responsible for an estimated 195,000 deaths occurred globally in 2008. Active research is ongoing to better understand the pathogenesis, immunology, and diagnosis of pertussis. For diagnosis, molecular assays (e.g., polymerase chain reaction) for detection of Bordetella pertussis have become more widely available and support improved outbreak detection. In children, pertussis vaccines have been incorporated into routine immunization schedules and deployed for pertussis outbreak control. Lower levels of vaccine coverage are now being observed in communities where vaccine hesitancy is rising. Additionally, recognition that newborn babies are at risk of pertussis in the USA and UK has led to recommendations to immunize pregnant women. Among adolescents and older adults in the USA, Tetanus Toxoid, Reduced Diphtheria Toxoid and Acellular pertussis (Tdap) Vaccines are recommended, but substantial individual- and system-level barriers exist that will make achieving national Healthy People 2020 targets for immunization challenging. Current antimicrobial regimens for pertussis are focused on reducing the severity of disease, reducing rates of sequelae, and minimizing transmission of infection to susceptible individuals. Continued surveillance for pertussis will be important to identify opportunities for reducing young infants' exposure and reducing the impact of outbreaks among school-aged children. Laboratory-based surveillance for newly emerging strains of B. pertussis will be important to identify strains that may evade protection elicited by currently available vaccines. Efforts to develop new-generation pertussis vaccines should be considered now in anticipation of vaccine development programs, which may require ten or more years to deliver a licensed vaccine.

Management and prevention of pertussis infection in neonates

Despite the fact that universal immunization against pertussis led to a dramatic decrease in the incidence and mortality in high-income countries, it has left a window of vulnerability for newborns. Although specific guidelines concerning management of neonatal whooping cough have not yet been developed, the present review summarizes the main available recommendations on diagnostic work-up and treatment of neonatal pertussis. Additionally, new prevention strategies are explored, including the use of an additional booster dose of vaccine to adolescents and adults, vaccination of healthcare workers, immunization of household contacts and caregivers (cocooning strategy), vaccination of pregnant women and, finally, neonatal immunization with novel vaccines. These strategies are analyzed and discussed in terms of efficacy, safety and cost-effectiveness.

Vaccination of healthcare personnel: spotlight on groups with underlying conditions

Healthcare personnel (HCP) are at increased risk of acquiring vaccine-preventable diseases (VPDs). Vaccination protects HCP and their patients from nosocomial transmission of VPDs. HCP who have underlying diseases (e.g., immunocompromised, HIV-infected, or those with chronic diseases) and HCP in particular phases of life (e.g., pregnant, elderly) require special consideration in regards the provision of vaccines. On the one hand, live virus vaccines may be contraindicated (e.g., pregnant HCP, immunocompromised HCP), while on the other hand, vaccines not routinely recommended (e.g., pneumococcal) may be indicated (e.g., elderly or immunocompromised HCP). It is not known how many HCP with underlying conditions require special consideration in the healthcare setting. This is an important issue, because the risk for serious morbidity, complications and mortality for HCP with underlying conditions will only increase. The prevention of nosocomial infections requires comprehensive occupational safety programs. The healthcare system must engage HCP and occupational physicians to ensure sufficient vaccination rates as part of an effective nosocomial infection prevention and HCP safety strategy.

Healthcare workers as vectors of infectious diseases

Nosocomial infections cause considerable morbidity and mortality. Healthcare workers (HCWs) may serve as vectors of many infectious diseases, many of which are not often primarily considered as healthcare-associated. The probability of pathogen transmission to patients depends on several factors, such as the characteristics of a pathogen, HCW and patient. Pathogens with high transmission potential from HCWs to patients include norovirus, respiratory infections, measles and influenza. In contrast, human immunodeficiency virus (HIV) and viral hepatitis are unlikely to be transferred. The prevention of HCW-associated transmission of pathogens include systematic vaccinations towards preventable diseases, continuous education, hand hygiene surveillance, active feedback and adequate staff resources.