Are You Ready for the Next Influenza Outbreak?

Conflicting reports in the media have healthcare professionals wondering exactly what this year’s influenza season will bring – a pandemic of novel H1N1 flu or a mild seasonal outbreak. In late August, the media seized upon a presidential advisory panel report that indicated as many as 90,000 U.S. deaths could be attributable to novel H1N1 influenza, that up to 50 percent of U.S. population could be infected this fall and winter, and that flu illnesses could trigger as many as 1.8 million U.S. hospital admissions.

The report issued by the President’s Council of Advisors on Science and Technology¹ suggests that 30,000 to 90,000 deaths are projected as part of a “plausible scenario” involving large outbreaks at schools, inadequate antiviral supplies and the virus peaking before vaccinations have time to be effective. To keep this number in perspective, experts add that seasonal influenza can claim as many as 40,000 lives annually. Every year in the U.S., on average, up to 20 percent of the population is infected with seasonal flu. On average, more than 200,000 hospitalizations occurred each year from 1979 to 2001 as a result of flu and its complications. In addition, on average, approximately 36,000 persons died each year from 1990 to 1999 from the flu and its related complications; more than 90 percent of these deaths occurred among persons 65 years of age or older.

The world first learned of H1N1 influenza in late April, and on June 11, the World Health Organization (WHO) declared the H1N1 virus a global pandemic. More than 1,490 people around the world have died from the virus since it emerged this spring.

Public health officials are unsure of what the fall will bring. CNN has quoted Thomas Frieden, director of the Centers for Disease Control and Prevention (CDC), as remarking, “Even with the best efforts, this will cause some illness, some severe illness and unfortunately, some deaths... But a lot so far has gone remarkably right. There’s a vaccine well on its way to being distributed, diagnostic tests available in well over 100 laboratories, treatments pre-positioned around the country ... and guidance issued for healthcare providers, schools, businesses and other communities.”²

The report caused CDC officials to retreat from some of the grim scenarios the statistics suggested and instead advised people to proceed carefully, lest a panic ensue. The New York Times quoted Anne Schuchat, MD, director of the National Center for Immunization and Respiratory Diseases, as saying, “We don’t necessarily see this as a likely scenario.” Times reporter Donald G. McNeil Jr. also reported, “A press officer for the disease centers, speaking carefully to avoid a feud with the White House press office, said, ‘Look, if the virus keeps behaving the way it is now, I don’t think anyone here expects anything like 90,000 deaths.’”²

While some believe that H1N1 fears are fading, others are concerned that the U.S. will be hard hit if complacency is allowed to undermine preparedness efforts.

“We definitely have to be on guard and prepared,” says William Schaffner, MD, chairman of the Department of Preventive Medicine and professor of infectious diseases at Vanderbilt University School of Medicine. “It’s a convergence, with the reopening of schools and colleges, so I think we will see an early H1N1 influenza season. What that means to all of us in healthcare, of course, is that we must be prepared to manage increased patient loads in hospitals’ emergency, outpatient and inpatient departments.“

Hospital capacity in a potential pandemic scenario is a concern. “This infection has sought out children and young adults, so by and large, when those people get ill it’s a relatively minor illness and they get over it,” Schaffner says. “However, if a vast number are infected — even though the proportion of serious illness is low — if there are many, many people infected, that means there is going to be a substantial number of people who are seriously ill who will be showing up at healthcare facilities. Older persons are much less affected, probably because they have seen a relative of this virus 40 or 50 years ago and they have some residual protection. So I think that’s where this concept of a ‘mild’ flu season comes in, but nonetheless, there will be some turbulence in our society — there will be some school closings and that means parents have to stay home, and hospitals will have workers who are sick or who will have to take care of their children, etc.”

Hospital Flu Readiness

Some healthcare professionals are nervous about hospitals’ readiness for another, potentially more serious outbreak.

A survey of 190 U.S. hospitals compiled by registered nurses in eight states finds that a number of healthcare facilities are not prepared for a potential novel H1N1 flu pandemic, according to survey results released in late August by the California Nurses Association/National Nurses Organizing Committee. The data reflects a survey conducted over the past four weeks by RNs in hospitals in Arizona, California, Florida, Illinois, Maine, Minnesota, Nevada, Pennsylvania and Texas.

What the RNs reported are wide gaps in safety gear, infection prevention and control training, and post-exposure procedures. Among key findings:

At more than one-fourth of the hospitals, nurses cite inadequate isolation of swine flu patients, increasing the risk of infection to others.

Nurses at 15 percent of hospitals do not have access to the proper respirator masks, exposing nurses and patients to infection; at up to 40 percent of the hospitals, nurses are expected to re-use masks, in violation of Centers for Disease Control and Prevention (CDC) guidelines.

At 18 percent of the hospitals, RNs report that nurses have become infected; one Sacramento, Calif. RN has already died.

CNA/NNOC is calling on all hospitals to adhere to the highest standard of protection for patients and nurses to combat the expected onslaught of new cases this fall and winter, and urging legislators to strengthen public protections.

“These continuing problems increase the risk that many hospitals will become vectors for infection, with inadequate patient protections leading to a spread of the pandemic among other patients, their friends, family, and caregivers, and the surrounding community,” warns Deborah Burger, RN, CNA/NNOC co-president. “What we’re hearing from around the country is dangerous to patient health and safety, but with smart and clinically appropriate leadership we can fix policies in time for the upcoming pandemic.”

Among other findings:

At 19 percent of the hospitals all or some appropriate N95 respirator masks were not “fitted” to ensure their effectiveness against the virus.

More than 1 in 5 (22 percent of the facilities) do not have enough masks, say nurses.

Nurses at fewer than half of facilities report that they have been adequately trained on H1N1 issues, including identification of infected patients, and procedures for caring for these patients.

To help combat these problems, CNA/NNOC has called for:

Minimizing infection of hospital patients and workers by strict adherence to the highest standard of infection control procedures, including identification and isolation with appropriate ventilation of infected patients.

All hospital workers and visitors must be provided with appropriate protection gear at the highest government standards, including N95 respirator masks or better for all who enter the isolation room of a confirmed or suspected H1N1 patient.

Any RN who is unable to work due to contracting a communicable or infectious disease identified or treated in his or her hospital/clinic shall be guaranteed sick leave, not face disciplinary action, and shall be presumptively eligible for workers’ compensation.

Implement a moratorium on any closures of emergency rooms, layoffs of direct healthcare personnel and reductions of hospital beds.

Federal guidelines for protection must be developed that are consistent across agencies.

Disposable respirator masks must not be re-used. In the event of a demonstrated national mask shortage, facilities should adhere to government recommendations on mask conservation.

Influenza Vaccination

Every flu season has the potential to cause significant illness, hospitalizations and deaths, and the novel H1N1 flu virus could result in a particularly severe 2009-2010 flu season. Public health officials believe that vaccination is the best tool with which to prevent influenza. While the seasonal flu vaccine is unlikely to provide protection against novel H1N1 influenza, an H1N1 vaccine is currently in production and may be ready for the public this fall. The novel H1N1 vaccine is intended to be used in conjunction with the seasonal flu vaccine.

“I think we’re in for it, and I think we could actually have a double-barrel influenza season – we could have H1N1 followed by regular flu, because the two viruses don’t protect against each other,” Schaffner says. “So that’s why it’s very important that we take advantage of the regular influenza vaccine that will be available early and in abundance. I think vaccinating healthcare workers is probably the single most important preventive step that healthcare institutions could take. We don’t do a good enough job of that.”

Due to some uncertainty about what influenza season might bring, in late July, CDC’s Advisory Committee on Immunization Practices (ACIP) announced who should receive the novel H1N1 vaccine when it becomes available. The ACIP considered current disease patterns, populations most at-risk for severe illness based on current trends in illness, hospitalizations and deaths, how much vaccine is expected to be available, and the timing of vaccine availability in recommending these groups receive the novel H1N1 influenza vaccine:

Pregnant women

Household contacts and caregivers for children younger than 6 months of age

Healthcare and emergency medical services personnel

All people from 6 months through 24 years of age

Persons aged 25 through 64 years who have health conditions associated with higher risk of medical complications from influenza

Once the demand for vaccine for the prioritized groups has been met at the local level, providers can begin vaccinating everyone from the ages of 25 through 64 years. Current studies indicate that the risk for infection among persons age 65 or older is less than the risk for younger age groups. However, once vaccine demand among younger age groups has been met, programs and providers should offer vaccination to people 65 or older.

In mid-August, the government announced that instead of the anticipated 120 million doses of influenza vaccine to be available on or around Oct. 15, there would be approximately 45 million initial doses due to a manufacturing shortfall. The HHS says that about 20 million more doses will be shipped weekly until the government reaches the full 195 million doses ordered.

“I am a little worried about that,” Schaffner says. “That’s a big step down. So that will increase, I think, our work in trying to deliver this vaccine because it will stretch out the immunization period. It will mean we will have to work harder and the person who wishes to receive the vaccine will have to pay more attention to when it’s their turn to go and find it, if it is even available.”

Vaccination of Healthcare Workers

Although the CDC says that vaccination of healthcare workers is a critical step in preventing the spread of influenza, vaccination rates have traditionally hovered around 40 percent. One program designed to help increase flu vaccination among this population is the Joint Commission Resources (JCR)’s first-ever Flu Vaccination Challenge, a program launched just prior to the 2008/2009 flu season. During the program’s inaugural year, JCR challenged hospitals across the country to achieve a seasonal flu vaccination rate of 43 percent or higher. The goal was based on results from a 2005/2006 national survey of healthcare worker seasonal flu vaccination rates.

With help from the Flu Vaccination Challenge, about 1.1 million healthcare workers were vaccinated against the seasonal flu, and 94 percent of participating hospitals met this challenge. More than 1,700 hospitals participated in the Flu Vaccination Challenge, and approximately 78 percent of participating hospitals increased their healthcare workers’ flu vaccination rate from the previous year. On average, the total number of healthcare workers vaccinated against seasonal flu among participating hospitals increased by 14 percent.

“We are thrilled with the level of participation and enthusiasm from the hundreds of hospitals across the country that participated in ‘the Challenge’; however, we believe organizations can do better,” says Barbara M. Soule, RN, MPA, CIC, practice leader for infection prevention and control services at JCR. “Despite the encouraging results, nearly 40 percent of healthcare workers among the participating hospitals were not vaccinated and remained unprotected against the flu. Influenza occurs in healthcare settings and studies have shown that healthcare workers are a potential source of these infections.”

“All individuals who work in a healthcare facility should be vaccinated against the flu,” says Schaffner. “When we talk about whom to vaccinate, we have to change our mindset. Vaccination shouldn’t be limited to doctors and nurses; it should be encouraged for everyone who works in a healthcare facility. The flu is a highly contagious disease; therefore if you work in a healthcare setting, you may be needlessly putting patients at risk if you are not vaccinated against this preventable disease.”

JCR is introducing a tiered approach to setting this year’s seasonal flu vaccination goals. Healthcare facilities will be challenged to reach a 65 percent, 75 percent or 90 percent vaccination rate. The goals were determined by evaluating last year’s results and recognizing that most participating hospitals surpassed the national flu vaccination rate. JCR is also broadening the challenge to include healthcare workers in ambulatory and long-term care facilities, emphasizing the importance of flu vaccination and patient safety beyond the hospital setting. The 2009 Flu Vaccination Challenge began in late August and will continue until March 2010. For additional information regarding how healthcare facilities can help improve their flu vaccination rates, visit www.FluVaccinationChallenge.com.

Schaffner says that vaccination compliance among healthcare workers is in direct proportion to the importance healthcare institution leadership places upon it. “They can be the big motivators,” Schaffner says. “If you look at the hospitals that have had very high acceptance rates of immunization, it has been because of a committed senior leadership. It’s as though the leadership ‘gets religion’ about influenza immunization and its importance as a patient safety issue and they just determine they’re not going to do it half-heartedly anymore. They align the entire institution behind that goal and put internal controls in place so that if people are laggards, folks get after them and say, ‘This list says you have not been vaccinated, please take care of it.’ I think an institution that is sincerely committed can get to over 90 percent. And some institutions have gone so far as to make it mandatory. I think we are going to see what I might dub as ‘mandatory creep.’ Increasingly, institutions will get impatient with their own healthcare workers and say, ‘OK, you to work here, so it’s mandatory.’ I think people are going to get grumpy at healthcare workers and say, ‘Is that what it takes, we have to put a gun to your head before you do what you are supposed to do?’”

Schaffner says that vaccination, like other key infection prevention measures, will be an issue that needs continual focus. “My suspicion is that we have improved but we are far from perfect. I usually look at the glass half full but this is an occasion when I look at the empty half of the glass and I am dismayed at my professional colleagues who don’t get vaccinated against influenza and do not adhere to appropriate handwashing and PPE-related precautions. It’s dumbfounding.”

Antivirals for Influenza

Antiviral drugs can prevent viral replication and thus prevent serious flu complications. This fall, antivirals may be prioritized for persons with severe illness or those at higher risk for flu complications. In August, the World Health Organization (WHO) issued guidelines for the use of antivirals in the management of patients infected with the H1N1 pandemic virus. Emphasis was placed on the use of oseltamivir and zanamivir to prevent severe illness and deaths, reduce the need for hospitalization, and reduce the duration of hospital stays. The pandemic virus is currently susceptible to both of these drugs (known as neuraminidase inhibitors), but resistant to a second class of antivirals (the M2 inhibitors).

The WHO says that on an individual patient basis, initial treatment decisions should be based on clinical assessment and knowledge about the presence of the virus in the community. In areas where the virus is circulating widely in the community, clinicians seeing patients with influenza-like illness should assume that the pandemic virus is the cause. Treatment decisions should not wait for laboratory confirmation of H1N1 infection. A WHO panel indicated that oseltamivir, when properly prescribed, can significantly reduce the risk of pneumonia (a leading cause of death for both pandemic and seasonal influenza) and the need for hospitalization. Where oseltamivir is unavailable or cannot be used for any reason, zanamivir may be given.

Clinicians, patients and those providing home-based care need to be alert to warning signals that indicate progression to a more severe form of illness, and take urgent action, which should include treatment with oseltamivir. In cases of severe or deteriorating illness, clinicians may consider using higher doses of oseltamivir, and for a longer duration, than is normally prescribed.

Outside of hoarding during a pandemic, a primary concern relating to antivirals is cultivating resistance. Good antiviral stewardship is necessary to prevent novel H1N1 influenza or other strains from becoming resistant to drugs. Over the summer, several instances of resistance to Tamiflu have popped up, thus triggering concern among experts that antivirals could be misused. The WHO advises physicians not to provide Tamiflu or Relenza to individuals with mild or moderate illness and who are not in a high-risk group such as children under 5, pregnant women and those with certain existing health conditions.

During the height of the avian influenza scare in October 2005, Tamiflu hoarding became so prevalent that its manufacturer, Roche, temporarily suspended additional deliveries to the U.S. According to a study by the CDC and Medco Health Solutions, Inc., Tamiflu prescriptions jumped more than 300 percent during the fall of 2005, despite little or no influenza activity in the U.S. At that time, the Society for Healthcare Epidemiology of America (SHEA) and the Infectious Diseases Society of America (IDSA) developed a position statement on antiviral stockpiling for influenza preparedness that said, in part: “We advocate healthcare institutional reserves to improve local access for treatment of affected populations, but not prophylaxis of healthcare workers given the current shortage of antiviral drugs. We discourage personal stockpiles. We want to remind the public that there are a number of other steps that individuals can take to protect themselves against seasonal or pandemic influenza, including cough etiquette, handwashing and annual influenza vaccination.”

Personal Protective Equipment

Personal protective equipment (PPE) is the backbone of any influenza-prevention strategy, yet it’s alarming that healthcare professionals are choosing to forego this essential protection from droplet and airborne transmission.

As documented in the CDC’s MMWR Weekly, the CDC had received 48 reports of confirmed or probable infections with novel influenza A (H1N1) virus; of these, 26 reports included detailed case reports with information regarding risk factors that might have led to infection. Although the CDC provided interim recommendations to reduce the risk for transmission in healthcare settings soon after identification of novel influenza A (H1N1) virus infections in the United States in mid-April, it was discovered that many healthcare professionals were not observing these guidelines in practice. These CDC recommendations included the use of PPE, management of healthcare workers after unprotected exposures, and instruction of ill healthcare workers not to report to work.

To better understand the risk for acquiring infection with the virus among healthcare workers and the impact of infection-control recommendations, CDC solicited reports of infected healthcare workers from state health departments. Of the 26 cases, 13 healthcare workers were deemed to have acquired infection in a healthcare setting, including one instance of probable healthcare worker-to-healthcare worker transmission and 12 instances of probable or possible patient-to-healthcare worker transmission. Eleven healthcare workers had probable or possible acquisition in the community, and two had no reported exposures in either healthcare or community settings. Among 11 healthcare workers with probable or possible patient-to-healthcare worker acquisition and available information on PPE use, only three reported always using either a surgical mask or an N95 respirator. These findings suggest that transmission of novel influenza A (H1N1) virus to healthcare workers is occurring in healthcare and community settings and that additional messages aimed at reinforcing current infection-control recommendations are needed.

“I understand that all of us working on hospital wards and in the ED are very busy, but to not take those extra steps in compliance, is puzzling,” says Schaffner. “It has everything to do with not only our safety, but patient safety, and I don’t know what it’s going to take to achieve absolute compliance with PPE usage.”

The Institute of Medicine (IOM), the same agency that created a stir with its landmark “To Err is Human” report that put medical errors on everyone’s radar in 1999, is turning its attention to the issue of PPE and the H1N1 influenza outbreak. In response to a request from the CDC and the Occupational Safety & Health Administration (OSHA), an ad hoc committee of the IOM was to conduct a study on PPE and issue a report to the CDC director and assistant secretary for occupational safety and health by Sept. 1, 2009.  

The committee’s goal was to provide recommendations regarding the necessary PPE for healthcare workers in their workplace against the novel influenza A (H1N1) virus. Issues to be addressed included the potential for exposure to the nH1N1 virus among healthcare workers, which groups of workers are at risk, which patient care activities pose a risk of exposure and what degree of risk, and what is known and what is unknown about transmissibility, severity and virulence of the current virus and how transmissibility might change.

The committee based its recommendations on the available current state of scientific and empirical evidence about nH1N1 virus, as well its expert judgment. Economic and logistical considerations regarding PPE equipment will not be addressed in this letter report. In determining the appropriate PPE for the U.S. healthcare workforce, attention will be given to the current PPE guidance documents offered by the CDC and by the World Health Organization for novel H1N1 influenza and for seasonal influenza.

A workshop was held in mid-August to examine the emerging science and clinical experience base associated with nH1N1; to discuss criteria used to delineate infection control guidelines; to discuss criteria used to assess risk to the healthcare workforce; and to examine what is known about the effectiveness of medical masks, respirators, gowns, gloves and eye protection in preventing nH1N1 and seasonal influenza transmission.

Taking great interest in this IOM-spearheaded endeavor is the Society for Healthcare Epidemiology of America (SHEA) and the Infectious Diseases Society of America (IDSA). Just shortly before the IOM’s announcement of the PPE study, SHEA had released a joint position statement, endorsed by the IDSA, the Association for Professionals in Infection Control and Epidemiology (APIC), and the Council of State and Territorial Epidemiologists (CSTE), calling for revision of the CDC’s Interim Guidance on Infection Control Precautions for Novel Swine-Origin Influenza A H1N1 in Healthcare Facilities.

In a letter to the IOM from SHEA and the IDSA in August, Lisa Maragakis, MD, MPH, from Johns Hopkins, explained that in an official statement, SHEA and IDSA had “endorsed the CDC’s initial recommendations on H1N1 as being consistent with evidence available as the virus emerged and was reflective of an appropriately cautious approach to containment at a time of ambiguity regarding transmission characteristics and severity of illness in the initial weeks of the outbreak.” However, Maragakis explained, “the statement called for amendment of the infection prevention and control guidance in light of additional knowledge and experience concerning the transmission dynamics and severity of the H1N1 outbreak. Available data and clinical experiences suggest that novel H1N1 transmission occurs, like seasonal influenza, via droplet spread. Therefore, it is our expert conclusion that current evidence supports handling H1N1 on the basis of droplet transmission consistent with recommended precautions for seasonal influenza.”

SHEA and IDSA endorse the following precautions for suspected or confirmed cases of novel H1N1 influenza:

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 healthcare worker’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 cohorting them with other patients infected with influenza

Strict adherence to hand hygiene, respiratory hygiene and cough etiquette

Restricting visitors and healthcare workers with febrile respiratory illnesses

SHEA and IDSA say that because they recognize that “certain medical procedures characterized by the potential for intensive cough induction and the immediately proximity of the operator’s face to the source of the cough (such as intubation or bronchoscopy) might produce concentrated aerosols of influenza or other viruses,” they support the CDC’s recommendation for the use of higher levels of respiratory protection, such as fitted respirators, under these limited circumstances. The groups explain that “These recommendations recognize that patient care includes a wide range of possible scenarios, and appropriately distinguishes standard care activities from procedures where a possible risk of airborne transmission may exist due to the nature of the procedure.”

However, SHEA and IDSA emphasize that PPE overkill should be avoided: “Beyond the types of procedures and close contacts noted in the previous statement, the marginal incremental and theoretical benefits of higher levels of respiratory protection for most routine clinical contacts in the healthcare environment do not justify the additional cost, time, discomfort, and burden of widespread N95 respirator use for an infection which all scientific authorities agree is primarily transmitted in the community by non-airborne routes.”

SHEA and IDSA reiterate that, “Universal adherence to basic infection prevention practices is the critical foundation to ensure healthcare worker safety. In addition to appropriate use of personal protective equipment, healthcare workers 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.”

Other important control measures embraced by SHEA and the IDSA are early recognition and isolation of suspected nH1N1-infected patients upon presentation to a healthcare facility and restriction of visitors and healthcare workers with febrile respiratory illnesses. The organizations state, “Without consistent application of these infection prevention measures in our healthcare institutions, no level of respiratory protection will offer adequate prevention of influenza transmission.”

Essentially, SHEA and IDSA stress that the current strain of novel H1N1 has the same transmission dynamics as seasonal influenza and should be managed as such based on the currently available scientific evidence.

Facemasks and Respirators

In its “Interim Recommendations for Facemask and Respirator Use to Reduce Novel Influenza A (H1N1) Virus Transmission,” and in ”Interim Guidance on Planning for the Use of Surgical Masks and Respirators in Health Care Settings during an Influenza Pandemic,” the CDC outlines guidance for the use of these key pieces of PPE.

The CDC emphasizes the differences between facemasks and respirators: “Facemasks do not seal tightly to the face and are used to block large droplets from coming into contact with the wearer’s mouth or nose. Most respirators (N95) are designed to seal tightly to the wearer’s face and filter out very small particles that can be breathed in by the user. For both facemasks and respirators, however, limited data is available on their effectiveness in preventing transmission of H1N1 (or seasonal influenza) in various settings. However, the use of a facemask or respirator is likely to be of most benefit if used as early as possible when exposed to an ill person and when the facemask or respirator is used consistently.”

Facemasks

Unless otherwise specified, the term ”facemasks” refers to disposable facemasks cleared by the U.S. Food and Drug Administration (FDA) for use as medical devices. This includes facemasks labeled as surgical, dental, medical procedure, isolation, or laser masks. Such facemasks have several designs. One type is affixed to the head with two ties, conforms to the face with the aid of a flexible adjustment for the nose bridge, and may be flat/pleated or duck-billed in shape. Another type of facemask is pre-molded, adheres to the head with a single elastic band, and has a flexible adjustment for the nose bridge. A third type is flat/pleated and affixes to the head with ear loops. Facemasks cleared by the FDA for use as medical devices have been determined to have specific levels of protection from penetration of blood and body fluids. Facemasks help stop droplets from being spread by the person wearing them. They also keep splashes or sprays from reaching the mouth and nose of the person wearing the facemask. They are not designed to protect against breathing in very small particle aerosols that may contain viruses. Facemasks should be used once and then thrown away in the trash.

Respirators

Unless otherwise specified, “respirator” refers to an N95 or higher filtering face piece respirator certified by the CDC/National Institute for Occupational Safety and Health (NIOSH). A respirator is designed to protect the person wearing the respirator against breathing in very small particle aerosols that may contain viruses. A respirator that fits snugly on the face can filter out virus-containing small particle aerosols that can be generated by an infected person, but compared with a facemask it is harder to breathe through a respirator for long periods of time.

Where respirators are used in a non-occupational setting, fit-testing, medical evaluation and training are recommended for optimal effectiveness. When respiratory protection is required in an occupational setting, respirators must be used in the context of a comprehensive respiratory protection program as required under OSHA’s Respiratory Protection standard (29 CFR 1910.134). This includes fit-testing, medical evaluation and training of the worker. When required in the occupational setting, tight-fitting respirators cannot be used by people with facial hair that interferes with the face seal.

Employers should continue to evaluate workplace hazards related to the novel H1N1 influenza A situation in accordance with CDC and OSHA guidance. Mandatory use of respiratory protection may be required when work activities in occupational settings confer risk that is task/function based, and risk analyses conducted by the employer could identify hazardous work activities. For example, performing activities which generate large amounts of aerosols require respiratory protection regardless of the setting in which it is performed (i.e., in a hospital or in an outpatient setting).

The CDC says that the prioritization of respirator use during a pandemic remains unchanged: N95 (or higher) respirators should be worn during medical activities that have a high likelihood of generating infectious respiratory aerosols, for which respirators (not surgical masks) offer the most appropriate protection for healthcare personnel. Use of N95 respirators is also prudent for healthcare personnel during other direct patient care activities (e.g., examination, bathing, feeding) and for support staff who may have direct contact with pandemic influenza patients. If N95 or other types of respirators are not available, surgical masks provide benefit against large-droplet exposure and should be worn for all health care activities involving patients with confirmed or suspected pandemic influenza. Measures should be employed to minimize the number of personnel required to come in contact with suspected or confirmed pandemic influenza patients.

PPE and the Mechanics of Influenza Transmission

Influenza is transmitted from person to person through close contact. Transmission occurs through multiple routes, including large droplets; direct and indirect contact; and fine droplet inhalational transmission. According to the CDC, the epidemiologic pattern observed is consistent with transmission through close contact (i.e., exposure to large respiratory droplets, direct contact transfer of virus from contaminated hands to the nose or eyes, or exposure to small-particle aerosols in the immediate vicinity of the infectious individual [known as “short-range exposure to aerosols”]). The relative contributions and clinical importance of the different modes of influenza transmission are unknown. While some studies acknowledge the possibility of short-range airborne transmission through small-particle aerosols, evidence of airborne transmission of influenza viruses from person to person over long distances (e.g., through air-handling systems, or beyond a single room) has not been demonstrated.

Droplet Transmission

Droplet transmission involves contact of the mucous membranes of the nose or mouth or the conjunctivae of a susceptible person with large-particle droplets containing microorganisms generated by an infected person during coughing, sneezing or talking. Transmission via large-particle droplets requires close contact between source and recipient persons because these larger droplets do not remain suspended in the air and generally travel only short distances. Three feet has often been used by infection control professionals as a guide for “short distance” and is based on studies of respiratory infections); however, for practical purposes, this distance may range from 3 to 6 feet. Special air handling and ventilation are not required to prevent droplet transmission. On the basis of epidemiologic patterns of disease transmission, large droplet transmission—via coughing and sneezing—has traditionally been considered a major route of seasonal influenza transmission.

Airborne Transmission

Airborne transmission occurs by dissemination of small particles or droplet nuclei through the air. Some organisms such as Mycobacterium tuberculosis can remain infectious while dispersed over long distances by air currents, causing infection in susceptible individuals who have not had face-to-face contact with the infectious individual. Special air handling and ventilation systems (e.g., negative-pressure rooms or airborne isolation rooms) are used in health care settings to assist in preventing spread of agents that may be dispersed over long distances. In contrast to tuberculosis, the pattern of disease spread for seasonal influenza does not suggest transmission across long distances (e.g., through ventilation systems); therefore, negative pressure rooms are not needed for patients with seasonal influenza. However, localized airborne transmission may occur over short distances (3 to 6 feet) via droplet nuclei or particles that are small enough to be inhaled.

Contact Transmission (Direct and via Fomites)

Contact transmission of influenza may occur through direct contact with contaminated hands, skin, or fomites followed by auto-inoculation of the respiratory mucosa. Influenza transmission via contaminated hands and fomites has been suggested as a contributing factor in some studies. There are insufficient data to determine the proportion of influenza transmission that is attributable to direct or indirect contact. However, it is prudent to reinforce recommendations for thorough and frequent handwashing, which is known to reduce the likelihood of contamination of the environment and to reduce transmission of respiratory infections. Surgical mask or respirator use may provide an additional benefit by discouraging facial contact and subsequent autoinoculation.

Use of appropriate barrier precautions such as masks, gloves and gowns during patient care, as recommended for Standard and Droplet Precautions, can be critical in fighting seasonal influenza and preventing further transmission. However, the CDC says, “the relative contributions of each of the interventions remain unknown, and their specific impact during a pandemic is difficult to predict.”

The CDC’s interim guidance for H1N1 influenza makes PPE recommendations for healthcare settings.

Use of Surgical Masks and Respirators in Healthcare Settings

Surgical mask and respirator use is one component of a system of infection control practices to prevent the spread of infection between infected and non-infected persons where pandemic influenza patients receive healthcare services. During an influenza pandemic, surgical masks and respirators—along with other forms of personal protective equipment (gloves, gowns and goggles)—should be used by personnel in healthcare settings in conjunction with Standard and Droplet Precautions, respiratory hygiene, cough etiquette, vaccination, and early diagnosis and treatment. Recommendations are:

NIOSH-certified respirators (N95 or higher) are recommended for use during activities that have a high likelihood of generating infectious respiratory aerosols

Use of N95 respirators for other direct care activities involving patients with confirmed or suspected pandemic influenza is also prudent. Hospital planners should take this into consideration during planning and preparation in their facilities when ordering supplies. The CDC guidance acknowledges that shortages of respirators are likely in a sustained pandemic. Therefore, in the event of an actual or anticipated shortage, the CDC says that hospital planners must ensure that sufficient numbers of respirators are prioritized for use during high-risk procedures. This will require real-time supply monitoring to ensure that excess respirators are not held in reserve while healthcare personnel are conducting activities for which they would otherwise be provided respiratory protection. Conversely, excessive use of respirators could result in their unavailability for high-risk procedures. Decision guidance for determining respirator wear should consider factors such as duration, frequency, proximity, and degree of contact with the patient. For example, a nurse entering a room with a suspected or confirmed pandemic influenza patient to obtain vital signs should wear an N95 respirator. A housekeeper entering multiple rooms of confirmed or suspected influenza patients to mop floors or clean patient equipment should be similarly protected. Work activities such as those performed by a receptionist at the entrance of a hospital should be designed to prevent exposure of the worker to large numbers of potentially infected patients. In such situations, the use of transparent barriers or enclosures is preferable to the use of respirators. If supplies of N95 (or higher) respirators are not available, surgical masks can provide benefits against large droplet exposure, and should be worn for all care activities for patients with confirmed or suspected pandemic influenza.

Negative-pressure isolation is not required for routine patient care of individuals with pandemic influenza. If possible, airborne infection isolation rooms should be used when performing high-risk aerosol-generating procedures. If work flow, timing, resources, availability, or other factors prevent the use of airborne infection isolation rooms, it is prudent to conduct these activities in a private room or other enclosed area, if possible, and to limit personnel in the room to the minimum number necessary to perform the procedure properly.

Guidance for Correct Use

Respirator use should be in the context of a complete respiratory protection program in accordance with Occupational Safety and Health Administration (OSHA) regulations. Staff with responsibility for direct patient care should be medically cleared, trained, and fit-tested for respirator use on these topics: Proper fit-testing, wearing, and use of respirators; safe removal and disposal of respirators; and medical contraindications to respirator use. If a respirator that provides protection from splashes of blood or body fluids is needed, NIOSH-certified, FDA-cleared surgical N95 (or higher) respirators should be selected.

Persons who wear surgical masks or respirators should be advised that:

Surgical mask or respirator use should not take the place of preventive interventions, such as respiratory etiquette and hand hygiene.

To offer protection, surgical masks and respirators must be worn correctly and consistently throughout the time they are used.

Wearing a surgical mask or respirator incorrectly, or removing or disposing of it improperly, could allow contamination of the hands or mucous membranes of the wearer or others, possibly resulting in disease transmission.

Proper surgical mask or respirator use and removal include the following:

Prior to putting on a respirator or surgical mask, wash hands thoroughly with soap and water or use an alcohol-based hand sanitizer to reduce the possibility of inadvertent contact between contaminated hands and mucous membranes.

If worn in the presence of infectious persons, a respirator or surgical mask may become contaminated with infectious material; therefore, avoid touching the outside of the device to help prevent contamination of hands.

Once worn in the presence of a patient with patient with pandemic influenza, the surgical mask or disposable N95 respirator should be removed and appropriately discarded.

After the surgical mask or respirator has been removed and discarded, wash hands thoroughly with soap and water, or use an alcohol-based hand sanitizer.

Recognition of Flu and Containment in a Pandemic Scenario

According to the WHO, “The success of a strategy for containing an emerging pandemic virus is strictly time dependent... The feasibility of early detection, rapid response and containment depends on several assumptions:

The emerging virus causes moderate to severe acute respiratory illness, thus making the event visible and increasing the likelihood that it will be detected.

The detection of clusters of such cases immediately triggers the appropriate clinical, epidemiological and laboratory investigations.

Notification and assessment of the event occur rapidly, moving from the local, to the intermediate, to the national level.

External assistance for investigation and response is quickly requested when needed.

WHO emphasizes that routine control measures aimed at reducing opportunities for further transmission to occur should be initiated as soon as preliminary investigations of the detected clusters of cases confirm an existing epidemic. These measures should be strengthened and intensified concurrently as the risk assessment is being conducted in order not to lose time.

WHO recommends the following interventions be used during outbreak control:

Isolation of clinical cases of moderate-to-severe respiratory disease in respiratory isolation rooms or single rooms.

Identification and voluntary home quarantine of persons who have had close contact with a case, and their daily monitoring for symptom onset.

Administration of antiviral drugs for the treatment of cases and, if domestic supplies permit, for the targeted prophylaxis of close contacts.

Strict infection control and the use of personal protective equipment during the delivery of health are in healthcare facilities managing cases.

Intensive promotion of hand and cough hygiene.

Surface cleaning to reduce transmission via fomites and from infectious respiratory secretions on surfaces.

Appropriate waste management and disposal.

Informing the public of the outbreak and initiating social mobilization measures.

Surge Capacity and Isolation Issues

The SARS and avian influenza outbreaks jolted U.S. hospitals into re-examining their disaster and surge capacity preparedness. In June 2006, funding from the Department of Health and Human Services was intended to help states strengthen their ability to respond to public health emergencies and acts of terrorism. The Health Resources and Services Administration (HRSA) within the HHS had earmarked $450 million for states to cultivate their medical surge capacity, including the development of isolation capacity. HRSA’s surge/isolation capacity minimum expectation of states is to ensure that all participating hospitals have the capacity to maintain, in negative pressure isolation, at least one suspected case of a highly infectious disease, and that funding recipients must identify at least one regional healthcare facility that is able to support the initial evaluation and treatment of at least 10 adult and pediatric patients at a time in negative pressure isolation within three hours post-event.

Surge capacity is a healthcare institution’s ability to meet an increased demand for healthcare services in the event of a public health emergency or other natural or man-made disaster, while isolation capacity refers to the ability for healthcare facilities to segregate patients with an infections disease from the rest of the patient population to prevent further transmission of infectious microorganisms.

The CDC recommends the use of isolation precautions to manage known and suspected cases of influenza in a pandemic scenario, which means placing the patient in an airborne isolation room (AIR). An AIR is defined as a patient room meeting the following AIA criteria: is a private room; has negative directional airflow from common areas into the room; has a minimum of six to 12 air exchanges per hour [supplement with high efficiency particulate air (HEPA) filtration system or ultraviolet germicidal irradiation (UV), if insufficient dilutional ventilation]; and has direct exhaust to the outside of the building more than 25 feet from an air intake or exhaust through a HEPA filtration system. An airborne infection isolation unit (AII Unit) is defined as a separate, dedicated area to care for patients suspected or confirmed to have an infection capable of being transmitted via airborne droplet nuclei.

The New York State Department of Health, in its guidance document, “Environmental Control Measures for Airborne Infection Isolation Surge Capacity Planning in Health Care Facilities for Smallpox, SARS or Other Infections Potentially Transmitted via Airborne Droplet Nuclei,” recommends that facilities develop contingency plans for increasing numbers of patients requiring isolation. They should identify areas that can be quickly converted to cohort patients with the same infectious agent. If the infectious agent has the potential to be transmitted by airborne droplet nuclei, the areas for cohorting need to have negative directional airflow relative to other areas and air should be directly exhausted to the outside and not re-circulated to other areas.

In the event of a pandemic influenza scenario, hospitals must prepare their main patient-receiving areas, such as emergency departments (EDs), including directing patients with febrile rash or febrile respiratory conditions to don masks and report their symptoms immediately to triage staff. EDs and other receiving areas of the hospital should ensure that surgical masks, tissues, waste containers and alcohol-based handrubs are readily available for symptomatic patients. Waiting areas should have increased air exchanges and air-flow patterns that will minimize exposure to airborne infectious pathogens, if possible, such as a directional/downward airflow. If air is re-circulated, facilities should consider supplemental HEPA or enhanced filtration to decrease airborne contaminants. HEPA filtration in the healthcare environment has many purposes, including cleaning the air, increasing ventilation rates and increasing or creating negative pressure in a room. For infection prevention and control applications, the CDC recommends that only HEPA filters with a minimum removal efficiency of 99.97 percent of particles for particles 0.3 microns in diameter should be used. Supplemental ultraviolet germicidal irradiation (UVGI) can also be effective for air disinfection.

If the number or location of AIIRs is not sufficient or appropriate, facilities should cohort patients with the same infectious agent in a designated unit, floor, wing or building. Temporary negative-pressure isolation structures and decontamination shelters/anterooms for surge capacity also can help with an emergency response to hundreds of patients flooding a facility in an influenza pandemic situation. These flexible structures can be easy to set up and are cost-effective alternatives to more permanent surge capacity/isolation room solutions.

References:

1. President’s Council of Advisors on Science and Technology. Report to the President on U.S. Preparations for 2009 H1N1 Influenza. August 2009.

2. CNN. Report: Swine flu could cause up to 90,000 U.S. deaths. Aug. 24, 2009.