Pandemic influenza and the role of Infection Control Professionals

1. How do the contributions of PI&ICP impact infection control currently?

Three influenza A pandemics have occurred during the 1900s: H1N1/A strain pandemic was ongoing in 2009-2010 and other pandemic influenzas will inevitably occur in the future. This is baseline knowledge that every infection control professional needs to know and accept as he/she faces a sense of impotence in front of such event. The 1918-9 H1N1 “Spanish flu” outbreak was the most devastating pandemic, killing between 50 million and 100 million people. Records from an “open-air” hospital in Boston, Massachusetts, suggest that health care workers (HCWS) were spared the worst of the outbreak. A combination of fresh air, sunlight, scrupulous standards of hygiene, and reusable face masks appear to have substantially reduced deaths among some patients, and infections among HCWs. Considering such encouraging results based on infection control policy only, the contributions of infection-control professionals (ICP) are due in various aspects of prevention, such as early diagnosis and control of flu pandemic outbreak to reduce the risk of spreading the flu in the hospital setting, thereby protecting patients, employees, healthcare students and visitors.

2. What elements of PI&ICP need to be adhered to for prevention and control?

Since the re-emergence of TB infection in high-income countries, the SARS 2003 outbreak, the 2014-5 Ebola Virus Disease (EVD) outbreak in West Africa and the increasing rate of health-care associated infections (HCAI), ICPs have been recognized as having a priority role in the preparedness response. Talented ICPs are essential for operating an infection-control program. These individuals are usually registered nurses with clinical experience or medical technologists with experience in microbiology. The effective ICP must have a working knowledge of epidemiologic principles, basic microbiology and a clinically sound understanding of the operations of the health care institution. During the 1980s, the CDC recommended that hospitals have one ICP for every 250 beds. Since that time, the number of hospital beds has decreased, the severity of illness of hospitalized patients has markedly increased (with a corresponding increase in the number of beds in critical care unit), infection control issues in the out-patient setting have increased, and many new duties have been assumed by ICPs. In response, the Society for Healthcare Epidemiology of America (SHEA) has assessed that the CDC ratio is no longer valid or adequate. In a survey of University Health System Consortium hospitals, a median of one ICP full-time equivalent per 137 occupied beds was documented.

A survey using the Delphi method determined that the optimal ratio in acute care hospitals is one ICP per 100 to 125 beds. Recently, a survey in 152 Australian hospitals, the mean number of ICPs was 0.66 per 100 overnight beds (95% CI, 0.55-0.77). Infection control advice should be provided at different levels of the health care system, from the policy maker strategy up to the specific recommendations at hospital and district levels. Basic infection control measures are the cornerstone of disease management and need to be the focus of ICP and HCWs practice management of respiratory outbreaks, and particularly of pandemic influenza. Simple measures such as adequate hand washing and restricting the spread of respiratory secretion, to more involved measures such as personal protective equipment (PPE) are needed at different levels according to the infection risk assessment. Finally, ICPs should cover areas of communication and patient flow including triage, respiratory hygiene (hand hygiene and cough etiquette) of the patients, occupational health and safety, environmental hygiene, isolation of individuals, visitor restrictions, and immunization for at- risk people (i.e., vaccine for influenza and other respiratory infections).

3. What are the key conclusions from the available clinical trials or meta-analyses related to PI&ICP which guide infection control practice and policies?

Key infection control measures are detailed as follows:

• Placing surgical masks on patients with suspected or confirmed novel H1N1 influenza infection at the point of entry into any healthcare setting.

Only one author performed a RCT to assess the in vivo efficacy of correctly worn surgical and N95 respirator masks to filter reverse transcription-polymerase chain reaction (RT-PCR)–detectable virus in nine patients with laboratory-confirmed acute influenza. Surgical and N95 masks were equally effective in preventing the spread of PCR-detectable influenza.

• 2.

  Using surgical masks to cover the healthcare worker’s nose and mouth to prevent transmission of the influenza virus by droplets or hand contact during routine patient care activities.

Few studies have been conducted in healthcare settings, and there is limited evidence to support the effectiveness of either surgical masks or N95 respirators to protect healthcare personnel. One recent large trial in nurses found no difference in effectiveness between surgical masks and N95 respirators, although the confidence intervals were wide enough to include moderate effect sizes. Larger studies are needed to confirm the non-inferiority of surgical masks versus N95 respirators. Guidance provided by WHO for protection of HCWs against pandemic H1N1/A infection recommends the use of standard and droplet precautions (including surgical masks or a face shield) during most patient interactions, while N95 or equivalent respirators are recommended for aerosol-generating procedures.

• 3.

  Placing such patients in a single room, if available, or with other patients infected with influenza with strict adherence to hand hygiene, respiratory hygiene and cough etiquette.

In a longitudinal cohort in Singapore, increased surveillance for febrile symptoms, segregation in small working units and strict application of PPE, including the N95 mask, significantly reduced the Ab seroconversion to 2009 influenza AH1N1 of military HCWs compared to the general military personnel in which individuals were provided with general health education on respiratory and hand hygiene only (11% versus 44%, respectively, p<0.01).

• 4.

  Healthcare workers vaccination for influenza.

In November, 2000 the U.S. Department of Health & Human Services published a health promotion and disease prevention initiative, Healthy People 2010, establishing a goal of reaching a HCW influenza vaccination rate of 60% by 2010. Yet, the U.S. national vaccination rate for HCWs remained at unacceptably low levels for the following influenza seasons: 38% in 1999–2000, 42% in 2005–2006, 44% in 2006–2007, and 49% in 2007–2008. In 2006, in an attempt to address the failure to improve HCW vaccination rates, the U.S. Centers for Disease Control and Prevention (CDC) published recommendations which focused on three strategies: educating HCWs about the benefits of vaccination; providing annual, free on-site vaccinations; and obtaining signed declination forms for vaccine refusers. Recently, in September, 2008, a two-week HCW vaccination program based on such recommendations was launched using a sequential “push/pull” point-of-dispensing vaccination model in the Flushing Hospital Medical Center in New York. Using this innovative model to drill and exercise the emergency preparedness plans for infectious disease outbreaks, in 48 hrs, 72% of the employees were reached, with 54% of those accepting vaccination. This approach could serve as a dual platform for other institutions to improve their HCW vaccination rates and emergency preparedness planning. Mandatory influenza vaccination of HCWs would clearly have the most significant impact on improving acceptance rates as high as 98.4% but would still not obviate the need to regularly exercise emergency preparedness plans in preparation for other potential infectious disease threats. However, considering the more recent New York State regulations requiring HCWs who have direct contact with patients or who may expose patients to disease to be vaccinated against influenza, in September, 2009 the New York State Health Commissioner Richard Daines argued about the limits of a state’s power to compel individuals to engage in particular activities in order to protect the public.

In Virginia, at the BJC HealthCare, a large Midwestern health care organization with ∼26,000 employees, a 2008-9 mandatory influenza vaccination campaign successfully increased vaccination rates (98.4%). Ninety employees (0.3%) received religious exemptions, and 321 (1.2%) received medical exemptions. Reasons for medical exemption included allergy to eggs (33%), prior allergic reaction or allergy to other vaccine components (26%), history of Guillan-Barre´ syndrome (5%), and others (36%), including 14 because of pregnancy. Similarly, at Virginia Mason Medical Centre, WA, USA, a program for mandatory immunization of healthcare workers achieved a 98•5% uptake. Nurses who were members of a union were exempted, following a successful legal challenge by the Washington State Nurses Association; nevertheless, 90% of them voluntarily accepted immunization in support of colleagues who were not members of a union, and for whom it remained mandatory. The Committee on Infectious Diseases of the American Academy of Pediatrics recommended a mandatory influenza immunization for all HCWs. In Europe, the influenza vaccination in HCWs is generally low. In October 2012, in a Paediatric Hospital, in Madrid, Spain, an educational programme was implemented before the influenza season with a significant but still unsatisfactory increase in vaccination rates (from 30% to 40%, P = 0·007) mainly among physicians. Finally, in healthcare settings, the autonomy of healthcare workers must be balanced against patients’ rights to protection from avoidable harm and the moral obligations of HCWs not to place others at risk. The ethical discourse has run its course and it is time to introduce policies that introduce the appropriate precautions, and that monitor their effect to ensure benefits and minimize adverse effects. There is now a clear window of opportunity to resolve the disparities between policy and scientific evidence.

• 5.

  What are the consequences of ignoring key concepts related to PI&ICP?

“First, do no harm.” The edict reminds physicians that they must consider the possible harm that might be caused by any intervention or by ignoring the key concepts related to infection control. Among physicians, this phrase has been an expression of hope, intention, humility, and recognition of the fact that acting with good intentions only, and not on evidence -based literature may produce unwanted consequences.

• 6.

  What other information supports the key conclusions of studies of or advice from PI&ICP e.g., case control studies and case series?

In the London Imperial College, the role of droplet dispersion during non-invasive respiratory procedures of patients with flu-like symptoms was assessed compared to control patients: non-invasive ventilation and chest physiotherapy were droplet (not aerosol)-generating procedures, producing large droplets of > 10 mm in size. Due to their large mass, most fall out onto local surfaces within 1 m. The only device producing an aerosol was the nebulizer and the output profile is consistent with nebulizer characteristics rather than dissemination of large droplets from patients. These findings suggest that HCWs providing NIV and chest physiotherapy, working within 1 m of an infected patient should have a higher level of respiratory protection, but that infection control measures designed to limit aerosol spread may have less relevance for these procedures. To assess the triage methods needed in emergency departments to provide clinicians with a reliable method for determining a patient’s risk of adverse clinical outcome during pandemic influenza, a prospective cohort study was undertaken of patients with suspected pandemic flu presented at 3 hospitals in Manchester and Sheffield, UK during the second wave of the 2009 H1N1 pandemic. A standardized assessment form that included the CURB-65 score, PMEWS and a locally developed score system-the swine flu hospital pathway- was performed. Five adult patients (2 deaths and 3 patients requiring respiratory support) were identified among 481 H1N1 cases. The CURB-65 score and swine flu hospital pathway did not reliably detect these cases. The PMEWS score identified four out of five cases with a poor outcome and low specificity (See Table I). Further research is required to evaluate existing triage methods and develop new triage tools for suspected pandemic influenza.

Table I.n

• 7.

  Summarize current controversies regarding the p.i and the icp.

• The wide debate on mandatory vaccination is already detailed

• The false link between the high H1N1 infectivity rate and the poor outcome in the general population.

The controversy on H1N1 influenza infectivity and clinical outcome is mainly based on the different definition criteria to declare the pandemic phases that WHO released in previous years. In 1999, the definition included the occurrence of several outbreaks in at least one country and the spread to other countries jointly with the diagnosis of serious clinical conditions. In 2005, the WHO definition only describes the spread of secondary human cases in different geographic areas. The likely relationship between risk of a pandemic and severe clinical outcome is described in a footnote only, but it is cited five times throughout the text. In the current 2009 WHO definition, the declaration of pandemic phases is only based on the sustained human-to-human transmission, with no prediction of clinical outcome. At the time of declaration of the H1N1 pandemic phase in June, 2009, a major emphasis should have been used to provide reliable information on the risk, clinical severity and progression of the pandemic.

• What is the role or impact of PI&ICP relative to the rules or impact of other aspects of infection control? (See previous sections.).

• Please summarize the important clinical trials, meta-analyses, case control studies, cases series and individual case reports related to infection control and PI&ICP in separate tables.

Clinical trials related to infection control and PI&ICP

See Table II for N95 respirator and surgical mask use in comparative trials in influenza and SARS infection.

Table II.n

• Current controversies related to PI&ICP

Considering the high mortality rate of the novel H1N1 cases during the first outbreak wave in Mexico and the uncertainty regarding the viral transmission dynamics, suspected H1N1 patients were initially attended to in negative pressure rooms with the higher available safety standard operating procedure including the N95 mask or more, as was recommended by CDC. Now, despite a wide consensus on the implementation of the same practices recommended to prevent the transmission of seasonal influenza for the novel H1N1 virus, the CDC guideline still continues to have a different approach for pandemic and seasonal influenza. Only during seasonal influenza should HCWs don a facemask when entering the room of a patient with suspected or confirmed influenza. Transmission of influenza in acute care hospitals is a risk many magnitudes lower than the risk of community transmission. Strategies that place excessive focus on preventing influenza transmission within healthcare facilities are of limited utility in an outbreak and divert attention from important community control strategies. Finally, describing different behavior when facing pandemic or seasonal influenza viral strains can be misunderstood and induce confusion in the ICPs.

• 2.

  What existing national and international guidelines relate to PI&ICP? How do they differ?

There has been a relatively low incidence of nosocomial transmission among critically ill patients during the recent H1N1 flu outbreak, which may be due to following the robust infection control recommendations (hand washing, wearing gloves and gowns, and the use of surgical mask or N95 respirators) which reduced the risks of transmission of respiratory virus in the SARS outbreak. Finally, IDSA & SHEA and different national and international guidelines, agree and recognize that HCWs must employ rigorous and consistent application of basic infection control and personal hygiene practices at all times, including adherence to hand hygiene and cough etiquette to reduce the influenza viral transmission in the hospital setting. In particular, implementing the same practices recommended to prevent the transmission of seasonal influenza for the novel pandemic virus is a reliable option. IDSA & SHEA specifically endorse the following precautions for suspected or confirmed cases of H1N1:

• Early recognition and identification of suspected novel H1N1 influenza-infected patients upon presentation to a healthcare setting;

• Placing surgical masks on patients with suspected or confirmed novel H1N1 influenza infection at the point of entry into any healthcare setting;

• Using surgical masks to cover the HCW’s nose and mouth to prevent transmission of the influenza virus by droplets or hand contact during routine patient care activities;

• Placing such patients in a single room, if available, or with other patients infected with influenza;

• Strict adherence to hand and respiratory hygiene, cough etiquette and;

• Restricting visitors and healthcare workers with febrile respiratory illnesses.

The main controversial issue is based on the recommendation by CDC of the universal use of N95 particulate respirators for respiratory protection during routine patient care activities in case of pandemic influenza: the inappropriate and widespread use of N95 respirators for all novel H1N1 patient care activities does not provide increased protection against the virus and may have an adverse impact on patient and healthcare worker safety. IDSA & SHEA support the recommendation for enhanced respiratory protection only when performing certain aerosol-generating procedures on patients with suspected or confirmed pandemic influenza. Recently, the Australian government commissioned an evidence-based algorithm for inclusion in the 2008 revision of the Australian Health and Management Plan for Pandemic Influenza. The use of surgical mask to protect HCWs in case of non-aerosol generating procedures was recommended in both sustain and contain phases but divergent opinions were collected by panel’s members and were detailed in the algorithm. Finally, a recent systematic review and a meta-analysis showed that there were insufficient data to determine definitively whether N95 respirators were superior to surgical masks in protecting health care workers against transmissible acute respiratory infections in clinical settings.

• What other consensus group statements exist and what do key leaders advise?

The European Society of Intensive Care Medicine’s Task Force for Intensive Care Unit Triage during an Influenza Epidemic or Mass Disaster throughout a Delphi process identified a wide range of potential risks to patients, relatives and staff not only from ICU that may arise during a pandemic. Some of these risks may have clinical implications separate from primary viral risks and are detailed as follows:

• Infection-related.

  Risks of work-acquired infection or contamination as a result of caring for patients;

  Concerns about transmission of infection to family members;

  Risks of community-acquired infection in potentially crowded public transport.

• Work-related

  Inability to deliver normal standards of care because of limited resources or excess demands;

  Necessity to decrease patient admissions or limit escalation of care;

  Limitation of care interventions that would be continued in normal circumstances;

  Excessive workload and prolonged working hours;

  Potential disagreements with colleagues over treatment restriction decisions;

  Pressure to work or provide interventions outside of the employee’s normal working domain;

• Personal or psychologically-related

  Anxiety about personal or family risks;

  Distress relating to patient treatment restrictions: treatment limitation decision & avoidable deaths;

  Death of family members, friends or colleagues;

  Potential errors and failings from working outside areas of normal expertise;

  Antisocial or antagonistic interactions by family members;

  Fatigue-related anxiety;

  Lack of confidence in management infrastructures or support

• Personal or professional criticism and litigation-related

  Treatment limitation decisions;

  Standards for patient outcomes and increased complication rates as a consequence of care being provided by staff outside of their normal expertise;

  Death or serious complications occurring as a result of excessive workload or inability to supervise normally.

All these items should receive adequate consideration in the hospital-based preparedness and response plan to pandemic influenza. Those with managerial responsibilities for HCWs from general wards and ICU should be fully aware of the potential safety implications to staff and be involved in advanced planning to minimize the potential risks related to the occurrence of a pandemic influenza.

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