State law and influenza vaccination of health care personnel

Mandatory vaccination for seasonal influenza: what are nurses' views?

BACKGROUND

Preventing seasonal influenza is a public health priority but, although the benefits of vaccinating healthcare workers (HCWs) are emphasised, seasonal influenza vaccine uptake rates remain low. Voluntary vaccination policies have been less successful in achieving high vaccine uptake when compared to mandatory policies and the persistently low vaccine uptake among HCWs has fuelled debate on whether mandatory vaccination programmes should be implemented in the interest of patient safety.

AIM

This study explored nurses' views on mandatory vaccination policy for seasonal influenza.

METHODS

A self-selected sample (n=35) of qualified nurses working in two large hospital sites in Ireland participated in five focus groups. Data were analysed using Braun and Clarke's framework.

FINDINGS

Two themes were identified: (1) mixed views on mandatory vaccination and (2) leave nurses to make their own choice on vaccination.

CONCLUSION

This study provides an understanding of nurses' views regarding mandatory vaccination policy for seasonal influenza and highlights that individual choice and autonomy are crucial for vaccine acceptance.

Increasing Vaccination: Putting Psychological Science Into Action

Vaccination is one of the great achievements of the 20th century, yet persistent public-health problems include inadequate, delayed, and unstable vaccination uptake. Psychology offers three general propositions for understanding and intervening to increase uptake where vaccines are available and affordable. The first proposition is that thoughts and feelings can motivate getting vaccinated. Hundreds of studies have shown that risk beliefs and anticipated regret about infectious disease correlate reliably with getting vaccinated; low confidence in vaccine effectiveness and concern about safety correlate reliably with not getting vaccinated. We were surprised to find that few randomized trials have successfully changed what people think and feel about vaccines, and those few that succeeded were minimally effective in increasing uptake. The second proposition is that social processes can motivate getting vaccinated. Substantial research has shown that social norms are associated with vaccination, but few interventions examined whether normative messages increase vaccination uptake. Many experimental studies have relied on hypothetical scenarios to demonstrate that altruism and free riding (i.e., taking advantage of the protection provided by others) can affect intended behavior, but few randomized trials have tested strategies to change social processes to increase vaccination uptake. The third proposition is that interventions can facilitate vaccination directly by leveraging, but not trying to change, what people think and feel. These interventions are by far the most plentiful and effective in the literature. To increase vaccine uptake, these interventions build on existing favorable intentions by facilitating action (through reminders, prompts, and primes) and reducing barriers (through logistics and healthy defaults); these interventions also shape behavior (through incentives, sanctions, and requirements). Although identification of principles for changing thoughts and feelings to motivate vaccination is a work in progress, psychological principles can now inform the design of systems and policies to directly facilitate action.

Protecting Healthcare Personnel in Outpatient Settings: The Influence of Mandatory Versus Nonmandatory Influenza Vaccination Policies on Workplace Absenteeism During Multiple Respiratory Virus Seasons

OBJECTIVE To determine the effect of mandatory and nonmandatory influenza vaccination policies on vaccination rates and symptomatic absenteeism among healthcare personnel (HCP). DESIGN Retrospective observational cohort study. SETTING This study took place at 3 university medical centers with mandatory influenza vaccination policies and 4 Veterans Affairs (VA) healthcare systems with nonmandatory influenza vaccination policies. PARTICIPANTS The study included 2,304 outpatient HCP at mandatory vaccination sites and 1,759 outpatient HCP at nonmandatory vaccination sites. METHODS To determine the incidence and duration of absenteeism in outpatient settings, HCP participating in the Respiratory Protection Effectiveness Clinical Trial at both mandatory and nonmandatory vaccination sites over 3 viral respiratory illness (VRI) seasons (2012-2015) reported their influenza vaccination status and symptomatic days absent from work weekly throughout a 12-week period during the peak VRI season each year. The adjusted effects of vaccination and other modulating factors on absenteeism rates were estimated using multivariable regression models. RESULTS The proportion of participants who received influenza vaccination was lower each year at nonmandatory than at mandatory vaccination sites (odds ratio [OR], 0.09; 95% confidence interval [CI], 0.07-0.11). Among HCP who reported at least 1 sick day, vaccinated HCP had lower symptomatic days absent compared to unvaccinated HCP (OR for 2012-2013 and 2013-2014, 0.82; 95% CI, 0.72-0.93; OR for 2014-2015, 0.81; 95% CI, 0.69-0.95). CONCLUSIONS These data suggest that mandatory HCP influenza vaccination policies increase influenza vaccination rates and that HCP symptomatic absenteeism diminishes as rates of influenza vaccination increase. These findings should be considered in formulating HCP influenza vaccination policies. Infect Control Hosp Epidemiol 2018;39:452-461.

Mandatory influenza vaccination for all healthcare personnel: a review on justification, implementation and effectiveness

PURPOSE OF REVIEW

As healthcare-associated influenza is a serious public health concern, this review examines legal and ethical arguments supporting mandatory influenza vaccination policies for healthcare personnel, implementation issues and evidence of effectiveness.

RECENT FINDINGS

Spread of influenza from healthcare personnel to patients can result in severe harm or death. Although most healthcare personnel believe that they should be vaccinated against seasonal influenza, the Centers for Disease Control and Prevention (CDC) report that only 79% of personnel were vaccinated during the 2015-2016 season. Vaccination rates were as low as 44.9% in institutions that did not promote or offer the vaccine, compared with rates of more than 90% in institutions with mandatory vaccination policies. Policies that mandate influenza vaccination for healthcare personnel have legal and ethical justifications. Implementing such policies require multipronged approaches that include education efforts, easy access to vaccines, vaccine promotion, leadership support and consistent communication emphasizing patient safety.

SUMMARY

Mandatory influenza vaccination for healthcare personnel is a necessary step in protecting patients. Patients who interact with healthcare personnel are often at an elevated risk of complications from influenza. Vaccination is the best available strategy for protecting against influenza and evidence shows that institutional policies and state laws can effectively increase healthcare personnel vaccination rates, decreasing the risk of transmission in healthcare settings. There are legal and ethical precedents for institutional mandatory influenza policies and state laws, although successful implementation requires addressing both administrative and attitudinal barriers.

Seasonal influenza vaccination coverage and its determinants among nursing homes personnel in western France

BACKGROUND

Influenza-associated deaths is an important risk for the elderly in nursing homes (NHs) worldwide. Vaccination coverage among residents is high but poorly effective due to immunosenescence. Hence, vaccination of personnel is an efficient way to protect residents. Our objective was to quantify the seasonal influenza vaccination (IV) coverage among NH for elderly workers and identify its determinants in France.

METHODS

We conducted a cross-sectional study in March 2016 in a randomized sample of NHs of the Ille-et-Vilaine department of Brittany, in western France. A standardized questionnaire was administered to a randomized sample of NH workers for face-to-face interviews. General data about the establishment was also collected.

RESULTS

Among the 33 NHs surveyed, IV coverage for the 2015-2016 season among permanent workers was estimated at 20% (95% Confidence Interval (CI) 15.3%-26.4%) ranging from 0% to 69% depending on the establishments surveyed. Moreover, IV was associated with having previously experienced a "severe" influenza episode in the past (Prevalence Ratio 1.48, 95% CI 1.01-2.17), and varied by professional categories (p < 0.004) with better coverage among administrative staff. Better knowledge about influenza prevention tools was also correlated (p < 0.001) with a higher IV coverage. Individual perceptions of vaccination benefits had a significant influence on the IV coverage (p < 0.001). Although IV coverage did not reach a high rate, our study showed that personnel considered themselves sufficiently informed about IV.

CONCLUSIONS

IV coverage remains low in the NH worker population in Ille-et-Vilaine and also possibly in France. Strong variations of IV coverage among NHs suggest that management and working environment play an important role. To overcome vaccine "hesitancy", specific communication tools may be required to be adapted to the various NH professionals to improve influenza prevention.

Using the 4 pillars™ practice transformation program to increase adult influenza vaccination and reduce missed opportunities in a randomized cluster trial

Background

An evidence-based, step-by-step guide, the 4 Pillars™ Practice Transformation Program, was the foundation of an intervention to increase adult immunizations in primary care and was tested in a randomized controlled cluster trial. The purpose of this study is to report changes in influenza immunization rates and on factors related to receipt of influenza vaccine.

Methods

Twenty five primary care practices were recruited in 2013, stratified by city (Houston, Pittsburgh), location (rural, urban, suburban) and type (family medicine, internal medicine), and randomized to the intervention (n = 13) or control (n = 12) in Year 1 (2013-14). A follow-up intervention occurred in Year 2 (2014-15). Demographic and vaccination data were derived from de-identified electronic medical record extractions.

Results

A cohort of 70,549 adults seen in their respective practices (n = 24 with 1 drop out) at least once each year was followed. Baseline mean age was 55.1 years, 35 % were men, 21 % were non-white and 35 % were Hispanic. After one year, both intervention and control arms significantly (P < 0.001) increased influenza vaccination, with average increases of 2.7 to 6.5 percentage points. In regression analyses, likelihood of influenza vaccination was significantly higher in sites with lower percentages of patients with missed opportunities (P < 0.001) and, after adjusting for missed opportunities, the intervention further improved vaccination rates in Houston (lower baseline rates) but not Pittsburgh (higher baseline rates). In the follow-up intervention, the likelihood of vaccination increased for both intervention sites and those that reduced missed opportunities (P < 0.005).

Conclusions

Reducing missed opportunities across the practice increases likelihood of influenza vaccination of adults. The 4 Pillars™ Practice Transformation Program provides strategies for reducing missed opportunities to vaccinate adults.

Trial registration

This study was registered as a clinical trial on 03/20/2013 at ClinicalTrials.gov, Clinical Trial Registry Number: NCT01868334, with a date of enrollment of the first participant to the trial of April 1, 2013.

Association of increased influenza vaccination in health care workers with a reduction in nosocomial influenza infections in cancer patients

BACKGROUND

Vaccination of health care workers (HCWs) remains a key strategy to reduce the burden of influenza infections in cancer patients.

METHODS

In this 8-year study, we evaluated the effect of a multifaceted approach, including a mandatory influenza vaccination program, on HCW vaccination rates and its effect on nosocomial influenza infections in cancer patients.

RESULTS

The influenza vaccination rate of all employees significantly increased from 56% (8,762/15,693) in 2006-2007 to 94% (17,927/19,114) in 2013-2014 (P < .0001). The 2009 mandatory participation program increased HCW vaccination rates in the targeted groups (P < .0001), and the addition of an institutional policy in 2012 requiring influenza vaccination or surgical mask use with each patient contact further increased vaccination rates by 10%-18% for all groups in 1 year. The proportion of nosocomial influenza infections significantly decreased (P = .045) during the study period and was significantly associated with increased HCW vaccination rates in the nursing staff (P = .043) and in personnel working in high-risk areas (P = .0497).

CONCLUSIONS

Multifaceted influenza vaccination programs supported by institutional policy effectively increased HCW vaccination rates. Increased HCW vaccination rates were associated with a reduction in the proportion of nosocomial influenza infections in immunocompromised cancer patients.

Influenza Immunization for All Health Care Personnel: Keep It Mandatory

The purpose of this statement is to reaffirm the American Academy of Pediatrics' support for a mandatory influenza immunization policy for all health care personnel. With an increasing number of organizations requiring influenza vaccination, coverage among health care personnel has risen to 75% in the 2013 to 2014 influenza season but still remains below the Healthy People 2020 objective of 90%. Mandatory influenza immunization for all health care personnel is ethical, just, and necessary to improve patient safety. It is a crucial step in efforts to reduce health care-associated influenza infections.

Immunization Update V

With all the new vaccines and strategies for prevention, the most important challenge that one continues to talk about globally and at home is the one presented by ongoing transmission of diseases for which excellent vaccines already exist. As pediatricians, this presents a constant reminder to keep the conversation about the importance of vaccine-preventable diseases with the patients and their families going at every possible opportunity possible. One needs to constantly remind oneself that every case of a vaccine-preventable disease is a missed opportunity for prevention. One must also have a broader perspective for global eradication of vaccine-preventable disease and advocate for availability of vaccines globally at affordable cost and encourage local vaccine development.

Evaluation of the impact of the 2012 Rhode Island health care worker influenza vaccination regulations: implementation process and vaccination coverage

CONTEXT

In October 2012, the Rhode Island Department of Health (HEALTH) amended its health care worker (HCW) vaccination regulations to require all HCWs to receive annual influenza vaccination or wear a surgical mask during direct patient contact when influenza is widespread. Unvaccinated HCWs failing to wear a mask are subject to a fine and disciplinary action.

OBJECTIVE

To describe the implementation of the 2012 Rhode Island HCW influenza vaccination regulations and examine their impact on vaccination coverage.

DESIGN

Two data sources were used: (1) a survey of all health care facilities subject to the HCW regulations and (2) HCW influenza vaccination coverage data reported to HEALTH by health care facilities. Descriptive statistics and paired t tests were performed using SAS Release 9.2.

SETTING AND PARTICIPANTS

For the 2012-2013 influenza season, 271 inpatient and outpatient health care facilities in Rhode Island were subject to the HCW regulations.

MAIN OUTCOME MEASURE

Increase in HCW influenza vaccination coverage.

RESULTS

Of the 271 facilities, 117 facilities completed the survey (43.2%) and 160 facilities reported vaccination data to HEALTH (59.0%). Between the 2011-2012 and 2012-2013 influenza seasons, the proportion of facilities having a masking policy, as required by the revised regulations, increased from 9.4% to 94.0% (P < .001). However, the proportion of facilities implementing Advisory Committee on Immunization Practices-recommended strategies to promote HCW influenza vaccination did not increase. The majority of facilities perceived benefits to collecting HCW influenza vaccination data, including strengthening infection prevention efforts (83.2%) and improving patient and coworker safety (75.2%). Concurrent with the new regulations, influenza vaccination coverage among employee HCWs in Rhode Island increased from 69.7% in the 2011-2012 influenza season to 87.2% in the 2012-2013 season.

CONCLUSION

Rhode Island's experience demonstrates that statewide HCW influenza vaccination requirements incorporating mask wearing and moderate penalties for noncompliance can be effective in improving influenza vaccination coverage among HCWs.

Nudges or mandates? The ethics of mandatory flu vaccination

According to the CDC report for the 2012-2013 influenza season, there was a modest increase in the vaccination coverage rate among healthcare workers from 67% in 2011-2012, to 72% in 2012-2013 to the current 75% coverage. This is still far from reaching the US National Healthy People 2020 goal of 90% hospitals vaccination rates. The reported increase in coverage is attributed to the growing number of healthcare facilities with vaccination requirements with average rates of 96.5%. However, a few other public health interventions stir so much controversy and debate as vaccination mandates. The opposition stems from the belief that a mandatory flu shot policy violates an individual right to refuse unwanted treatment. This article outlines the historic push to achieve higher vaccination rates among healthcare professionals and a number of ethical issues arising from attempts to implement vaccination mandates. It then turns to a review of cognitive biases relevant in the context of decisions about influenza vaccination (omission bias, ambiguity aversion, present bias etc.) The article suggests that a successful strategy for policy-makers and others hoping to increase vaccination rates is to design a "choice architecture" that influences behavior of healthcare professionals without foreclosing other options. Nudges incentivize vaccinations and help better align vaccination intentions with near-term actions.

A Successful Strategy for Increasing the Influenza Vaccination Rate of Healthcare Workers without a Mandatory Policy Outside of the United States: A Multifaceted Intervention in a Japanese Tertiary Care Center

Objective.

Although mandatory vaccination programs have been effective in improving the vaccination rate among healthcare workers, implementing this type of program can be challenging because of varied reasons for vaccine refusal. The purpose of our study is to measure improvement in the influenza vaccination rate from a multifaceted intervention at a Japanese tertiary care center where implementing a mandatory vaccination program is difficult.

Design.

Before-and-after trial.

Participants and Setting.

Healthcare workers at a 550-bed, tertiary care, academic medical center in Sapporo, Japan.

Interventions.

We performed a multifaceted intervention including (1) use of a declination form, (2) free vaccination, (3) hospital-wide announcements during the vaccination period, (4) prospective audit and real-time telephone interview for healthcare workers who did not receive the vaccine, (5) medical interview with the hospital executive for noncompliant (no vaccine, no declination form) healthcare workers during the vaccination period, and (6) mandatory submission of a vaccination document if vaccinated outside of the study institution.

Results.

With the new multifaceted intervention, the vaccination rate in the 2012-2013 season increased substantially, up to 97%. This rate is similar to that reported in studies with a mandatory vaccination program. Improved vaccination acceptance, particularly among physicians, likely contributed to the overall increase in the vaccination rate reported in the study.

Conclusions.

Implementation of comprehensive strategies with strong leadership can lead to substantial improvements in vaccine uptake among healthcare workers even without a mandatory vaccination policy. The concept is especially important for institutions where implementing mandatory vaccination programs is challenging.

Mandatory influenza vaccination for health care workers as the new standard of care: a matter of patient safety and nonmaleficent practice

A growing body of literature defends the efficacy of seasonal influenza vaccination for health care workers in reducing the mortality of hospitalized patients. I review the evidence concerning influenza vaccination, concluding that universal vaccination of health care workers against influenza should be considered standard patient care and that nonvaccination represents maleficent care. I further argue that the ethical responsibility to ensure universal vaccination of staff against seasonal influenza lies not only with individual health care providers but with each individual health care institution.

A qualitative analysis of the impact of healthcare personnel influenza vaccination requirements in California

OBJECTIVE

Using qualitative methods, we explored the implementation of California's 2007 influenza immunization requirements of hospital-based health care personnel (HCP).

METHODS

We conducted nine case studies of California hospitals with different HCP vaccination rates and policies. Case studies consisted of interviewing 13 hospital representatives and analyzing relevant hospital documents, including influenza policies. We also conducted 13 semi-structured phone interviews with key state and county public health officials, union representatives, and officials of various professional healthcare organizations.

RESULTS

Our qualitative results suggest that California's vaccination requirements likely did not increase influenza vaccination uptake among HCP. The law was not strong enough to compel hospitals with low and medium vaccination rates to improve their vaccination efforts, and hospitals with high vaccination rates were able to comply fully with the law by continuing to do what they were already doing - namely offering vaccinations to HCP, providing education about the risks of influenza and the benefits of vaccination, and obtaining signed declinations from those who refuse vaccination. Nonetheless, we found that by publicly raising the issue of influenza vaccination in the context of public safety and healthcare quality, California's law encouraged hospitals to develop and implement data systems to monitor the effectiveness of vaccination promotion efforts and prompted discussions, and, in some cases, adoption of stricter vaccination requirements at hospital or county levels.

CONCLUSIONS

Our findings generally support the literature that suggests that permissive influenza vaccination requirements, though politically feasible, provide little direct incentive for hospitals to focus efforts on increasing HCP vaccination rates.

Barriers and facilitators to influenza vaccination and vaccine coverage in a cohort of health care personnel

BACKGROUND

Annual influenza vaccination is recommended for health care personnel (HCP). We describe influenza vaccination coverage among HCP during the 2010-2011 season and present reported facilitators of and barriers to vaccination.

METHODS

We enrolled HCP 18 to 65 years of age, working full time, with direct patient contact. Participants completed an Internet-based survey at enrollment and the end of influenza season. In addition to self-reported data, we collected information about the 2010-2011 influenza vaccine from electronic employee health and medical records.

RESULTS

Vaccination coverage was 77% (1,307/1,701). Factors associated with higher vaccination coverage include older age, being married or partnered, working as a physician or dentist, prior history of influenza vaccination, more years in patient care, and higher job satisfaction. Personal protection was reported as the most important reason for vaccination followed closely by convenience, protection of patients, and protection of family and friends. Concerns about perceived vaccine safety and effectiveness and low perceived susceptibility to influenza were the most commonly reported barriers to vaccination. About half of the unvaccinated HCP said they would have been vaccinated if required by their employer.

CONCLUSION

Influenza vaccination in this cohort was relatively high but still fell short of the recommended target of 90% coverage for HCP. Addressing concerns about vaccine safety and effectiveness are possible areas for future education or intervention to improve coverage among HCP.

The impact of influenza vaccination requirements for hospital personnel in California: knowledge, attitudes, and vaccine uptake

BACKGROUND

Seasonal influenza infections are a leading cause of illness, death, and lost productivity. Vaccinating health care personnel (HCP) can reduce transmission of influenza virus to patients and reduce influenza-related absenteeism, enabling the health care system to meet elevated demand for care during influenza outbreaks.

OBJECTIVES

We evaluated the impact of California's 2006 influenza vaccination requirement for hospital workers (requiring vaccination or signed declinations) on uptake and vaccination-related attitudes, beliefs, and knowledge among hospital HCP.

METHODS

We used a causal difference-in-differences approach to compare changes over the prior 10 years in the self-reported frequency of influenza vaccination for California hospital HCP and those from other states without similar laws using data from a stratified sample (N = 3,529) of HCP drawn from online survey panels. We also examined cross-sectional differences in awareness of vaccination policies, promotion efforts, and attitudes toward influenza vaccination. All analyses used propensity score weighting to balance the observable characteristics of the 2 samples.

RESULTS

We found that compared with their counterparts in other states, California hospital HCP were (1) more likely to report working under a formal written policy for influenza vaccination, (2) no more likely to be vaccinated, and (3) less likely to report working for an employer who provided financial incentives for vaccination or rewarded or recognized employees for being vaccinated.

CONCLUSION

Our results suggest that state-level vaccination requirements such as those enacted by California, may not be sufficient to increase uptake among hospital HCP.

Employee influenza vaccination in residential care facilities

BACKGROUND

The organizational literature on infection control in residential care facilities is limited. Using a nationally representative dataset, we examined the organizational factors associated with implementing at least 1 influenza-related employee vaccination policy/program, as well as the effect of vaccination policies on health care worker (HCW) influenza vaccine uptake in residential care facilities.

METHODS

The study was a cross-sectional study using data from the 2010 National Survey of Residential Care Facilities. Multivariate logistic regression analysis was used to address the study's objectives.

RESULTS

Facility size, director's educational attainment, and having a written influenza pandemic preparedness plan were significantly associated with the implementation of at least 1 influenza-related employee vaccination policy/program, after controlling for other facility-level factors. Recommending vaccination to employees, providing vaccination on site, providing vaccinations to employees at no cost, and requiring vaccination as a condition of employment were associated with higher employee influenza vaccination rates.

CONCLUSION

Residential care facilities can improve vaccination rates among employees by adopting effective employee vaccination policies.

The issue of mandatory vaccination for healthcare workers in Europe

Mandatory policies have occasionally been implemented, targeting optimal vaccination uptake among healthcare workers (HCWs). Herein, we analyze the existing recommendations in European countries and discuss the feasibility of implementing mandatory vaccination for HCWs. As reflected by a survey among vaccine experts from 29 European countries, guidelines on HCW vaccination were issued in all countries, though with substantial differences in targeted diseases, HCW groups and type of recommendation. Mandatory policies were only exceptionally implemented. Results from a second survey suggested that such policies would not become easily adopted, and recommendations might work better if focusing on specific HCW groups and appropriate diseases such as hepatitis B, influenza and measles. In conclusion, guidelines for HCW vaccination, but not mandatory policies, are widely adopted in Europe. Recommendations targeting specific HCW groups and diseases might be better accepted and facilitate higher vaccine uptake than policies vaguely targeting all HCW groups.

Impact of hospital policies on health care workers' influenza vaccination rates

BACKGROUND

Overall annual influenza vaccination rate has slowly increased among health care workers but still remains below the national goal of 90%.

METHODS

To compare hospitals that mandate annual health care worker (HCW) influenza vaccination with and without consequences for noncompliance, a 34-item survey was mailed to an infection control professional in 964 hospitals across the United States in 4 waves. Respondents were grouped by presence of a hospital policy that required annual influenza vaccination of HCWs with and without consequences for noncompliance. Combined with hospital characteristics from the American Hospital Association, data were analyzed using χ(2) or Fisher exact tests for categorical variables and t tests for continuous variables.

RESULTS

One hundred fifty hospitals required influenza vaccination, 84 with consequences (wear a mask, termination, education, restriction from patient care duties, unpaid leave) and 66 without consequences for noncompliance. Hospitals whose mandates have consequences for noncompliance included a broader range of personnel, were less likely to allow personal belief exemptions, or to require formal declination. The change in vaccination rates in hospitals with mandates with consequences (19.5%) was nearly double that of the hospitals with mandates without consequences (11%; P=.002). Presence of a state law regulating HCW influenza vaccination was associated with an increase in rates for mandates with consequences nearly 3 times the increase for mandates without consequences.

CONCLUSION

Hospital mandates for HCW influenza vaccination with consequences for noncompliance are associated with larger increases in HCW influenza vaccination rates than mandates without such consequences.

Induction of innate immunity in lungs with virus-like nanoparticles leads to protection against influenza and Streptococcus pneumoniae challenge

Nanoparticles composed of the coat protein of a plant virus (papaya mosaic virus; PapMV) and a single-stranded RNA (ssRNA) trigger a strong innate immune stimulation in the lungs of the animals a few hours following instillation. A rapid recruitment of neutrophils, monocytes/macrophages and lymphocytes follows. This treatment was able to provide protection to an influenza challenge that lasts at least 5 days. Protection could be recalled for longer periods by repeating the instillations once per week for more than 10 weeks. The treatment also conferred protection to a lethal challenge with Streptococcus pneumoniae--the major cause of bacterial pneumonia. Finally, we also showed that the nanoparticles could be used to treat mice infected with influenza and significantly decrease morbidity. These data strengthen the potential for using PapMV nanoparticles as non-specific inducers of the innate immune response in lungs during viral pandemics or to combat bioterrorist attack.

FROM THE CLINICAL EDITOR

In this study, virus-like nanoparticles were utilized to induce innate immune responses in a mouse model. They were also demonstrated to provide enhanced immune responses during actual pneumonia and ongoing viral infection. Strategies like this may become very helpful in human applications, including bioterrorism countermeasures.