It's been a busy night. You feel like you have seen every headache and cough on the East Coast, and you just want to go home. As you hand your paperwork to your shift supervisor, you notice two new signs posted on the door. The first is a message from the Centers for Disease Control and Prevention (CDC) warning healthcare providers about a new virus being seen in a number of large cities in neighboring states. The virus is thought to be transmitted mainly via airborne particles and has been shown to be highly contagious, as well as fatal to a high percentage of elderly, young and immunocompromised patients. Initial symptoms being reported include intense headaches, overall body pain and coughing, with some patients experiencing acute onset of hemi/paraplegia. In addition to urging the use of PPE for contact, and respiratory and eye protection when dealing with suspected patients, 24/7 contact information for the CDC and local health authorities is prominently displayed at the bottom of the announcement.
Next to the CDC letter is a memorandum from the local health department announcing that a possible case of this new virus may have been identified in the greater metropolitan area yesterday. After reading both notices, you and your partner exchange alarmed looks and begin to review the chief complaints of all the runs your unit completed in the last 12 hours.
Smallpox. Tuberculosis. Polio. All of these were once classified as emerging infections that ravaged populations in the U.S. and abroad. Development of vaccines and treatment modalities worked to erase them from Western health concerns, but lack of healthcare in third world countries, lax security at bio-stocks in the former Soviet Union and the appearance of new drug-resistant infections are breathing new life into old threats.
Monkeypox. Ebola virus. Severe Acute Respiratory Syndrome (SARS). As travel and commerce circles continue to make our world an ever-closer community, previously isolated illnesses are being carried across oceans and continents within days of outbreak, often without warning. Aside from business as usual, does EMS have any true, distinct responsibilities regarding emerging infections? If so, what are they?
Infectious diseases have emerged, disappeared and reemerged over the course of the millennia, causing death and disability among unprotected populations all over the globe. There are numerous explanations for the ebb and flow of these biological enemies, including ecological factors (such as climate and weather), presence of animal populations, changes in travel patterns, microbial evolution and adaptation, as well as sociological aspects like sanitation and housing.
Whatever the reason for these past scourges, in the 21st century, emerging infections still pose unique challenges to the full spectrum of healthcare, EMS providers included. However, rarely do public health and other government officials recognize the prehospital arena as being in the line of fire when waging a fight against these threats. Published papers recording this acknowledgment are scarce, although the National Association of EMTs recently promulgated two policy papers specific to EMS providers regarding emerging infections, threatened or realized. The first, released in 2002, was a well-researched position statement on the proposals for smallpox vaccination of healthcare workers, with particular focus on the issues facing EMS providers.1 The second policy, issued in 2003, sought to address the Severe Acute Respiratory Syndrome (SARS) outbreak ravaging cities in Asia and Canada, providing important accounts of the specific impact of SARS to EMS systems. The policy also included updates from the CDC and the World Health Organization (WHO) regarding patient clinical presentation and recommended protective measures for providers rendering care to SARS patients.2 In its September 2004 edition, the CDC's Journal of Emerging Infectious Diseases published an overview letter from several emergency physicians in the Toronto area regarding the effect of SARS on the overall functioning of Toronto EMS and the concessions-operational, clinical and otherwise-that were necessary for the system to adequately handle the infection.3
But other than these examples, EMS systems have been largely ignored in the onslaught of information, both provided and collected, in regard to increased awareness, protection and reporting of emerging infectious disease.
So what exactly is an emerging infectious disease? A good, inclusive definition is offered by the University of Washington School of Public Health: "a new, reemerging or drug-resistant infection whose incidence in humans has increased within the past two decades or threatens to increase in the near future."4 Immediately, this definition encompasses the disease alluded to in the opening and brings to mind some other, better-known infections such as multi-drug-resistant tuberculosis (MDR-TB) and HIV/AIDS. Another recent classification from Columbia University in New York City refers to three circumstances: 1. A new, previously unknown infectious agent or disease; 2. A previously described infectious agent in a new geographic location, as a new syndrome, in a new type of host or with an increased drug-resistant pattern or other new genetic characteristic; 3. New or previously described infectious agents used as bioweapons.5
Our Own Worst Enemy
According to CDC statistics, Western healthcare is not only part of the solution to battling emerging disease, but is unfortunately often a key part of the problem. Failure to follow well-established personal and patient-protective protocols as simple as handwashing and use of respiratory PPE has led to increasing healthcare-associated infections in North America. As a result, 1.8 million hospitalized patients are infected and 88,000 die annually in the U.S. alone. Five main pathogens are associated with 50% of all reported infections: Staphylococcus aureus, enterococcus, Candida, Escherichia coli and Klebsiella pneumoniae. The 2003 SARS epidemic, both in Asia and Canada, demonstrated how one emerging pathogen can have a profound impact as a healthcare-associated infection. In addition to poor communication between the various public health entities and front-line medical care, healthcare-associated transmission of SARS was a primary accelerator of the disease in Toronto and Taiwan.6
The SARS experience represents the confluence of both emerging infection issues and patient safety issues. A report created by the Public Health Agency of Canada in 2004 noted that SARS was contained not through modern high-tech drugs or advances in microbiology, but by "old-fashioned public health measures like handwashing, infection control procedures, isolation of cases, and tracing and quarantine of contacts."7 Maintaining vigilance for the presence of healthcare-associated infections is a vital component of both preventing emerging infectious diseases and improving patient safety.
To highlight how important following standardized PPE can be, following are three examples of current emerging infections by mode of transmission:
Airborne-Avian Influenza (H5N1) Although there are at least 15 different types of avian influenza that routinely infect birds around the world, the strain known as H5N1 is highly contagious among current avian populations, is rapidly fatal and, most important, can be transmitted to humans. While symptomatically similar to SARS, influenzas are caused by a completely different virus that is more contagious, highly unstable and has the ability to mutate rapidly.
One of the most recent zoonotic pathogens to cross from animal populations to humans, H5N1 packs the potential for a lethal punch: Roughly 50 people have died in the past year in Asia due to exposure to this strain of influenza; the CDC puts the mortality rate of those infected at 72%. Where H5N1 is currently found mostly in rural and farm communities where animal-human contact is the greatest, a real fear is that it could evolve into a form that is more easily spread between people. In order to become a pandemic strain, the avian virus would need to adapt on its own, or mix its genetic material with a human virus. If someone already infected with the human flu were to become infected with H5N1, the two viruses could recombine inside the victim's body, producing a hybrid that could readily spread from person to person. The resulting virus would likely be something humans would have no immune defense against. It is predicted that such an infection could cause devastating illness not seen since the 1918-19 Spanish flu pandemic, which killed an estimated 40 million-50 million worldwide. Recent reports that H5N1 has been found in swine populations in Indonesia-and that human cases have appeared there and in Cambodia-make these possibilities even more frighteningly probable.8-12
Blood-/fluid-borne-Marburg Virus. The second of only two known natural outbreaks of this rare, severe type of hemorrhagic fever appeared in Angola in October 2004. Caused by a genetically unique zoonotic disease fever that affects both humans and primates, Marburg is the only known relative of the Ebola viruses. Spread to humans through direct contact with body fluids (e.g., blood, saliva and urine) of an infected person or animal, including corpses, the virus has been reported to survive for as long as several days on contaminated surfaces.
According to the CDC, Marburg presents as an acute febrile illness with chills, headache and myalgia after an incubation period of 5-10 days. Approximately the fifth day after onset of symptoms, a raised rash, nausea, vomiting, chest pain, sore throat, abdominal pain and diarrhea might appear. Increasing in severity over time, the disease leads to severe weight loss, delirium, shock, liver failure, massive hemorrhaging, multi-organ dysfunction and usually death. There is no cure or vaccine, and supportive treatment is the only care available for those infected.
So far, the only outbreaks have occurred in sub-Saharan Africa, but there has already been an escalation in the morbidity and mortality numbers from the 1998-2000 outbreak seen in the Congo, where 149 cases were identified with 123 fatalities. In Angola, from October 1, 2004, to March 29, 2005, a total of 124 cases were identified; of these, 117 were fatal. The number of cases attributed to the Marburg virus then doubled from just March to May of this year, jumping to 337, with a death rate of 92% among those infected. National and international health organizations are waging a war not only against a virus that is deadly and virulent, but also an indigenous population that has lost faith in its healthcare system to contain the disease as new cases continue to be identified even among hospital and other health workers.13-16
A naturally occurring bacteria, Staphylococcus aureus ("staph") has long been the bane of healthcare providers. Lack of consistent observation of simple infection-control procedures, such as handwashing and use of contact PPE, has made staph infections the most common problem found among hospitalized patients. With the widespread use-and abuse-of antibiotics, methicillin-resistant Staphylococcus aureus (MRSA) has also become an established pathogen in most Western healthcare facilities. Resistant to methicillin-related antibiotics like penicillin, as well as new antimicrobial drugs developed for penicillin-resistant infections (e.g., oxacillin, nafcillin), MRSA most commonly causes skin infections that, if left untreated, can become abscessed and spread into the bloodstream. In recent years, however, infections due to MRSA have been documented in children and adults who lack the traditional risk factors, such as premature birth/low birth weight, chronic underlying diseases, prolonged hospitalization, invasive or surgical procedures, indwelling catheters or prolonged use of antimicrobial agents. Without this higher index of suspicion, the resulting soft tissue infections are therefore not immediately seen as life-threatening. In some parts of the southern and southwestern United States, it has been reported that the lesions are often thought to be spider bites and are not treated as serious until they reach an advanced stage. Commonly called the "flesh-eating disease," serious infections have also been known to cause pneumonia, sepsis and organ failure.
Because CA-MRSA is passed by close physical contact, either with somebody who is infected or contaminated material-including clothing or bedding-those in close social and living environments, like school sports teams, children in daycare and residents of nursing homes, are more likely to be exposed. A recent study published by the New England Journal of Medicine analyzed the prevalence of MRSA in three U.S. communities and determined that almost 20% of these cases were CA-MRSA in origin-much higher than the authors thought they would find. Studies have also found that while the CA-MRSA is related to the hospital-based strains, it is usually more virulent. Without the development of new antimicrobial drugs, it is feared that the incidence of what would otherwise be a relatively benign infection will only continue to increase unabated with no tools to combat its spread.17-22
Weaponization of Biologicals
No discussion on emerging infections and their various implications on healthcare systems in general, and EMS systems in particular, would be complete without a brief overview of the applicable history of the use of infectious disease as a weapon, as well as some current measures proposed to mitigate their consequences.
The earliest documented attempt to use a disease to cause harm was in 1346, as the black plague was moving across Crimea and the Middle East at the same time the Mongols were attacking ports along eastern trading routes. According to a local notary of the time, during a siege of Caffa, a port in what is present-day Ukraine, a Mongol force catapulted bodies of dead plague victims into the city.23 Although this first written account of the use of a deadly infectious disease as a weapon is certainly impressive in its barbarity, if not its creativity, the overall effectiveness of the attack is still questionable. Both sides were impacted by the exposures, and the plague was already being widely disseminated by the travels of sailors and other traders using those routes.
Later, in the colonial periods of the Americas, disease was both allowed to do its damage and purposefully introduced into populations. Following contact with Europeans, Native Americans suffered 80%-90% population losses with influenza, typhoid, measles and smallpox taking the greatest toll in devastating epidemics. However, as was seen in Caffa, these methods did not ensure selectivity, and the non-native African and European populations were also dramatically affected by the explosion of both epidemic and endemic diseases.24
In comparison to the "hit-and-miss" application of biological agents in the past, according to the World Health Organization (WHO), present-day biological weapons are specifically developed to achieve an intended target through the infectivity of disease-causing microorganisms and other such entities, like viruses. However, most biological agents that have been weaponized are used for the toxic substances that they generate. Since the toxins themselves are isolated and used to cause harm, the effect of these types of bioweapons are actually not as a result of infectivity but of toxicity. The WHO also recognizes that the intentional use of a biological agent would not be announced and that index cases would present at healthcare facilities for diagnosis and treatment. Because recognized clusters/cases would be investigated as suspected natural outbreaks until an unusual pathogen was confirmed and/or unusual epidemiological patterns were detected, diligence on the part of all public health partners is vital to early detection and mitigation.25
Reviewing the WHO recommendations to its member states concerned about the implementation of bioweapons, one finds directives that are easily adoptable to the needs of prehospital preparedness. On the whole, EMS systems should:
Strengthen ties to local public health surveillance and response activities
Monitor national/state/local surveillance of outbreaks of illness
Create better communication between responsible agencies (public health, public safety, emergency management) to better coordinate and prepare for responses
Improve assessments of vulnerability and effective communication about risks to both providers and patients
Prepare to handle the psychosocial consequences of the deliberate use of pathogens to cause harm
Develop contingency plans for an enhanced response capacity to support public health, law-enforcement authorities and other emergency management bodies.
As has been suggested by the WHO, an emerging infection will most likely not be recognized as such immediately. This is why EMS systems should endeavor to participate in public health and emergency management monitoring activities like those mentioned above. A rapidly improving technology being used for this monitoring is syndromic surveillance. Defined by the CDC as "using health-related data that precede diagnosis and signal a sufficient probability of a case or an outbreak to warrant further public health response," syndromic surveillance applied to EMS involves live analysis of data (e.g., 9-1-1 calls and dispatch logs) to identify patterns and trends as they emerge, rather than waiting days or weeks for conventional detection methods (e.g., patient chart review). The variables or triggers for a natural epidemic or artificially induced disease threat would include any cluster of predetermined key symptoms, such as breathing difficulties, abdominal pain, fever with rash or unconscious persons. Early detection allows appropriate action to be taken quickly, saving lives and protecting healthcare infrastructures. Unlike conventional syndromic surveillance data sources used in public health monitoring, such as reports from private physician visits or patterning of community pharmaceutical purchases, emergency medical services dispatch data is exceptionally time-sensitive, with systematically gathered information linking medical symptoms and accurate geographic locations of incidents.
A growing number of cities across the United States have already begun to utilize this technology for notification on various clusters of patients with specific illnesses or injuries, and, thus far, the system has performed above expectations.26 With these successes, the future holds the possibility of nationwide syndromic surveillance.
EMS Provider Protection
What can EMS providers actually do about emerging infections? Following the suspicion of the SARS outbreak, government authorities overseas immediately instituted certain policies (including the use of full personal protection for each EMS provider), as well as specific training (in infection control techniques) and frequent updates on the general situation to protect emergency medical services personnel.27
The importance of personal awareness and preparedness cannot be overstated. This means everything from paying attention to any public health updates provided around your station or medical control facility to knowing where the PPE is on your unit and using it, and considering chief complaints and symptoms of your patients in total. An important, yet constantly overlooked, component of an EMS provider's assessment is reconciling pertinent signs and symptoms with the patient's recent travel history (which countries and when), as well as other events (contact with certain animals, etc.) that should raise suspicion of an infectious disease. If you begin to see an unusual number of patients with common complaints, especially when they come from different groups (male vs. female, old vs. young, etc.), ask yourself why. Speak to the nurses and doctors at the emergency departments in your response area and ask if they have been seeing the same clustering of symptoms.
The list of protection to-dos for EMS must also include attention to basic rules of medical hygiene. Many of these commonsense practices are included in guidelines recommended by the CDC and required by OSHA:
Use appropriate PPE. This means gloves, gowns and a mask with eye protection (preferably with a face shield) if indicated by patient presentation and the need to conduct invasive procedures (e.g., IV catheterization and ET intubation). Also, after use, these items must be treated as medical waste and disposed of properly.
Use appropriate PPE on your patient. If concerned about a possible airborne contagion, place these patients on a non-rebreather mask or have them wear a surgical mask (depending on their oxygenation/ventilation needs). Contact with skin lesions can be minimized by wrapping the body part with loose gauze, or the entire patient with a clean sheet.
Clean your ambulance after every call. This must be done with suitable disinfectants, addressing all nondisposable equipment that was used for patient assessment/treatment, as well as vehicle surfaces.
Wash your hands after every patient contact. Glove use does not eliminate the need for hand hygiene. Using alcohol-based disinfectants offers an efficient and effective way to clean before and after each patient contact. If a glove layer is breached and hands become visibly dirty, wash them thoroughly with soap and tepid water, remembering to clean under the nails and on the backs of your hands.
Protection for the EMS provider, however, goes beyond the proper application of PPE when warranted. Preplanning and prevention are also half the battle. Despite OSHA requirements, many departments still do not have basics in place: comprehensive exposure control plans, trained personnel designated to function as exposure-control officers, or expanded and regularly updated education and training on infectious diseases. How many services reach out to local public health agencies to participate in annual flu vaccine programs? Unless you are about to be inspected by your local or state oversight body, does your department make sure all your employees' immunizations are up to date? The most important resource any EMS agency has is its personnel. The responsibility to protect that resource belongs to the entire organization.
Previously unseen and metamorphosized infections are making themselves known with alarming frequency. On February 18, 2005, two separate disease outbreaks were reported in the New York Times. One involved more than 400 people near Amsterdam who tested positive for TB following contact with an infectious supermarket cashier. More frightening was the report that an additional 21,000 people might have come in contact with the 400 already identified. The other report focused on an outbreak of rare pneumonic plague in the Congo, which killed more than 60 people and had the possibility of infecting hundreds more. Several thousand workers self-evacuated the area without any follow-up with medical authorities, fleeing "into the forests to escape the highly contagious disease."
At the opposite end of the public health experience are examples of how vigilance in identification and prevention of disease can and does make a difference. In August 2004, a man presented at a New Jersey hospital with Lassa fever, a highly contagious disease spread by rodents that is rarely seen outside of those areas in Africa where the disease is endemic. The patient, who had become symptomatic shortly before his return home from there, died before a treatment regimen could be started. The importance of this particular case is that the healthcare providers quickly reconciled the patient's symptoms and travel history to correctly identify a non-native disease. Proper PPE was immediately instituted, and public health tracking and testing of all possible contacts during the man's travel to the U.S. and in New Jersey were completed. Although 188 persons both within and outside the healthcare system were in contact with this person during the infectious stages, none had reported Lassa-like symptoms 30 days later.28 Likewise, cases of diphtheria being seen in the U.S. due to an ongoing epidemic in the former Soviet Union and endemic presentations in developing countries have been stalled from spreading due to continued requirements for early childhood vaccinations against the disease.29
EMS systems, and the providers who operate in them, cannot afford to live in the proverbial vacuum. Prehospital opera-tors-clinicians, administrators and medical directors-need real-time information about emerging infections, consistent communication with relevant healthcare authorities and constant updating of policies and procedures to reflect realities like those outlined in this article. What this translates to for EMS providers is the need to stay vigilant in regard to our preparedness (both as a group and individually) and our assessments, and not be lulled into thinking "it's just the flu." n
r 6. Jernigan D. Emerging Infections in Healthcare Delivery: Roles for HL7 in Applied Public Health. Division of Healthcare Quality Promotion, National Center for Infectious Diseases. CDC. Presented 2003.