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Biological emergencies are caused by bacteria, viruses, and poisons made by bacteria. They can be spread into the air, used to contaminate food and drinking water, and be spread by person- to person contact. A biological emergency involves the release of a toxic substance via ventilation system, food or water supply, the mail, explosive device, or aerosol device during an accident or attack. A biological emergency may not be noticed until health care providers find a pattern. The progress of a disease is influenced by the epidemiological triangle, which consists of the disease-producing agent, the affected host, and the environment. Epidemiologists with information about the cause of disease can identify populations at risk and employ levels of prevention to develop strategies that prevent, diagnose, and manage the occurrence. Analysis of current epidemics and future predictions are dependent on accurate data gathered through descriptive studies, analytical studies (cross-sectional, case-control or retrospective studies, and cohort studies), and experimental studies.
An epidemic can be defined as a disease affecting a significantly large number of people at the same time, over a large area. A disease that spreads rapidly through a demographic part of the human population, such as everyone in a given geographic area, a military base, or similar population unit, the children or women of a region, or a disease or event whose incidences is beyond what is expected. A few cases of very rare disease may be classified as an epidemic, while many cases of a common disease (common colds) would not
A pandemic of a disease is occurrence throughout the population of a country, a people, or the world. The outbreak and spread of infectious diseases depends upon pre-existing levels of the disease, ecological changes resulting from disaster, population displacement, changes in density of population, interruption of basic health services, disruption of public utilities, and compromises to sanitation and hygiene (American Public Health Association, 2005, 1).
Prevention is any action directed to preventing disease and promoting health to eliminate the need for secondary and tertiary health care. Prevention includes such nursing actions as assessment, immunization, health teaching, screening, and recognition of disability limitations and rehabilitation potential. In emergency care nursing, many interventions are simultaneously preventive and therapeutic.
Vaccination is used as an important part in the control of epidemics. A suspension of attenuated or killed microorganisms are administered intradermally, intramuscularly, orally, or subcutaneously to induce active immunity or to reduce the effects of associated infectious diseases, such as smallpox, typhoid, measles, mumps, polio, pneumococcal and influenza vaccines. Immunization of elderly patients against influenza is especially important because of their increased risk for severe complications.
The risk for panic reactions to epidemics increases during disaster situations, and it is very important that correct information is spread as soon as possible. Listen for reports on the television, radio or internet (by sms). These messages should include accurate information about:
The general hygiene is of significant importance for the spread of an epidemic (access to clean water and sewage system). Epidemics may be person- to person diseases (contact and respiratory spread), vector-born diseases, water and/or food-born diseases, and complications from wounds. Disinfection and sterilization of re-used material is probably in a disaster situation. Isolation precautions for preventing the transmission of infection may be accomplished; but many facilities do not have enough rooms appropriately designed and ventilated for isolation. Quarantine (in schools, retirement homes) is reserved for isolation of people with the same communicable disease or those exposed to communicable diseases during the contagious period in an attempt to prevent spread of illness, or for the practice of detaining travelers or vessels coming from places of epidemic disease, for the purpose of inspection or disinfection.
Vaccination (immune prophylaxis). At certain epidemics, it is possible to limit the outbreak by vaccination. Sometimes due to lack of vaccine, one must prioritize the immunization based on risk groups; medical risk groups (those with pre-existing cardiovascular or lung diseases and/or old age), and epidemiological risk groups (for example, police and health care workers). Certain vaccines that can be present at disaster situations are vaccines against hepatitis A, hepatitis B, influenza A, cholera, meningococcus, and typhoid. Antibiotic prophylaxis may be used in cases of anthrax, and when epidemics of streptococcus or meningococcus occur in a closed population, such as a military base.
Wound infections probably increase during disasters; emergency wound management are common interventions. Resistant microorganisms, such as Methicillin-Resistant Staphylococcus Aureus (MRSA), and gas gangrene, caused by Clostridium perfringens may occur. MRSA requires expensive and toxic antibiotics, for example vancomycin. Gas gangrene, necrosis accompanied by gas bubbles in soft tissue, pain, swelling and tenderness of the wound area, moderate fever, tachycardia, hypotension, and toxic delirium. Prompt treatment, including excision of gangrenous tissue (amputation) and penicillin G, save 80% of patients (Anderson, Anderson, & Glanze, 1998). The disease is prevented by proper wound care.
Airway infections. Three main strains of influenza has been recognized; type A, type B, and type C. Influenza type A (Asian flu) causes global epidemics while type B causes smaller, local outbreaks; type C is of little importance. Yearly vaccination with the currently prevalent strain of influenza A virus is recommended for debilitated or elderly persons and health care providers. Treatment or prophylaxis in high-risk patients may be achieved with amantadine (within 24 hours after onset). Streptococcal infections (streptococcus pyogenes) cause suppurative diseases, such as scarlet fever, wound infection, and strep throat. This bacteria tends to spread rapidly within schools and military bases. During war -and disaster situations large outbreaks can be expected; antibiotic prophylaxis. Air way infections caused by mycoplasma pneumonia or chlamydia pneumonia also occurs. Clinical symptoms are dry cough, fever, and headache.
Gastrointestinal infections and food poisonings often increases during disasters, due to incorrect food keeping (improperly canned or cooked foods). Botulism is an often fatal form of food poisoning caused by endotoxin produced by the bacillus Clostridium botulinum. The symptoms are lassitude, fatigue, headache, and visual disturbances. Muscles may become weak, and dysphagia often develops, from 18 hours after the contaminated food has been ingested. Antitoxins are administered. The fatality is high, usually as a result of delayed diagnosis and respiratory complications.
Acute gastroenteritis may result from an enterotoxin produced by certain species of Staphylococci aureus in contaminated food; violent diarrheas and vomits about 2 to 6 hours after the contaminated food has been ingested. Toxins from Clostridium perfringens is also a common cause of food poisoning (beef stew and casseroles). The patients get sick with abdominal pain and diarrhea but no vomits, 8-24 hours after the contaminated food has been ingested. Even Bacillus cereus, found in the soil, can cause food poisoning (an emetic type and a diarrheal type) by the formation of an enterotoxin in contaminated foods.
Cholera is spread by water and food that have been contaminated with feces of persons previously infected. It is an acute bacterial infection of the small intestine, characterized by severe watery diarrhea, muscular cramps, dehydration and depletion of electrolytes. Complications include circulation collapse, cyanosis, destruction of kidney tissue, and metabolic acidosis. Treatment includes the administration of antibiotics and the restoration of normal amounts of fluids and electrolytes with intravenous solutions. A cholera vaccine is available; other preventive measures include drinking only boiled or bottled water (decontaminated as by iodine), and eating only cooked food.
Salmonella infections, are caused by a genus of motile gram-negative rod-shaped bacteria that includes species causing typhoid fever, paratyphoid fever (spread from person- to person) and some forms of gastroenteritis (food-born diseases). The clinical picture of typhoid and paratyphoid is serious, and the patients should always have antibiotics. Salmonellosis, a form of gastroentiritis, caused by ingestion of food contaminated with a species of Salmonella is characterized by an incubation period of 6 to 48 hours followed by sudden colicky abdominal pain, bloody watery diarrhea, fever, nausea and vomiting. Antibiotics may prolong the excretion of Salmonella in stools and are usually not indicated. Adequate cooking, good refrigeration, and careful hand washing may reduce the frequency of outbreaks. The source of contamination must be traced, and those who are infected, especially if these persons work with food handling or within the healthcare.
Shigella dysenteriae, caused by shigella flexneri, shigella sonnei, and shigella boydii, is an infection that classically increases during disaster conditions. It is characterized by exudative colonic hemorrhagic diarrhea, abdominal pain, and fever. It is transmitted by hand-to-mouth contact with the feces of persons infected with bacteria of a pathogenic species of the genus shigella (incubation period 6 hours to 9 days). Supportive care, the major goal is prevention of dehydration; antibiotics shorten course (TMP/SMX (trimetoprim/sulfamethoxozole), norfloxacin, ciprofloxacin, ofloxacin).
Campylobacter move in a characteristic coil like motion and require little or no oxygen for growth. The symptoms are diarrhea, stomachache, and fever; require usually no treatment.
Viral enteritis, enterovirus is common in large epidemic outbreaks and is very contagious (contact- and respiratory (droplet) spread). Rotavirus replicates in the epithelial cells of the intestine and is a cause of acute gastroenteritis with diarrhea, particularly in infants (grandfathers- and grandmothers).
Calicivirus causes large outbreaks in institutions, for example, hospitals of vomiting, fever, and diarrhea. Transmission of caliciviruses is generally by the fecal-oral route, but they can also be transmitted via the respiratory route. There is no treatment or prophylaxis available.
Hepatitis A (HAV), acute infective hepatitis, is a virus infection with a fecal-oral (fecal contamination and oral ingestion) mode of transmission. Sources of infection and spread of disease during disaster situations are crowded conditions, poor personal hygiene and sanitation, contaminated food, milk, water and shellfish; persons with subclinical infections, infected food handlers, sexual contact. Prophylaxis with vaccine or immunoglobulin.
Blood products are usually controlled in regard to presence of blood borne diseases, such as hepatitis A, hepatitis B, HIV, HTLV-I, and HTLV-II (human T-cell lymphotropic virus- I and 2), this might not be possible during disasters and mass casualty situations, when the need of blood products can increase dramatically.
Hepatitis B (HBV), serum hepatitis, a form of viral hepatitis, where the virus is transmitted in contaminated serum in blood transfusion, by sexual contact with an infected person, or by the use of contaminated needles and instruments. A vaccine is available and recommended for infants, teenagers, and adults at risk for exposure.
Hepatitis E is the most common cause of non-A, non-B hepatitis worldwide. The most common group affected is young to middle-aged adults.
Sexually transmitted diseases (STI) are among the most common communicable diseases, and the incidence has risen in recent years despite improved methods of diagnosis and treatment. Cases of gonorrhea and chlamydia infections should be treated with antibiotics. There is an increased risk for STD at disasters; condoms are a good protection.
Meningococcal meningitis, caused by a bacterium frequently found in the nasopharynx of asymptomatic carriers. The onset is usually sudden and characterized by severe headache, high fever and meningitis symptoms, and hemorrhagic skin lesions. Early treatment with an appropriate antibiotic such as penicillin G is essential for cure. Several meningococcal vaccines are available. Increased frequencies of viral meningitis can be expected during disasters. Many of these diseases are benign and self-limited, such as meningitis caused by strains of coxsackievirus or echovirus. Others are more severe, such as arboviruses, herpesviruses, or poliomyelitis viruses.
Bioterrorism is the threatened or intentional release of disease-producing living organisms or biologically active substances derived from organisms to harm, kill, incapacitate people (even animals, or plants), or to cause economic damage or fear. The threat of bioterrorism, a biological attack, against a civilian population is recognized as a real danger. Biological agents are bacteria, viruses, fungi, and toxins; genetically altered or enhanced infectious agents, vaccine and multi-drug resistant organisms; including smallpox, anthrax, botulism, plaque, tularemia, Staphylococcal Enterotoxin B Intoxication, and viral hemorrhagic fever (the Ebola and Marburg Viruses). It is essential to identify the mode of transmission and clinical characteristics of biological agents, and to identify infection control methods to prevent disease transmission. Response plans, implementation of decontamination procedures, as well as ways to preparing, documenting, reporting, and responding to a bioterrorist attack needs extra skills and training. There are many national, international and worldwide surveillance systems that provide a description or assessment of disease patterns in the population, and enhance timely detection of the event. Only adequate preparation can ensure low morbidity and mortality from intentional use of biological agents even in the future.
Terrorist attacks are often totally unexpected and unpredictable. After the terrorist attack on September 11, 2001 against World Trade Center in New York and Washington D.C., it was established for the first time signs of bioterrorism with Anthrax. The events of September-October 2001 involving the deliberate delivery of anthrax spores through the US postal system are an example from the intentional use of biologic agents as weapons and tools of fear. After the anthrax attacks in the US 2001, the EU Council launched measures to prepare for bioterrorism and to improve cooperation among the member states and the EU Commission in Brussels (Sundelius, & Gronvall, 2004).
Despite international agreements that biological weapon should not be used in wars, such as the 1972 Biological and Toxic Weapons Convention, the facts remain that lethal and highly noxious biological agents are relatively inexpensive, are easy to obtain, are relatively easy to produce, are easy to conceal, and are becoming increasingly easily to deliver (Relman, & Olson, 2001). Continuing political and military instability focuses sharp attention on the known capabilities of nations such as Iraq, Iran, Syria, and Korea. Developed missile warheads, bombs and rockets armed with botulinum toxin, anthrax, and aflatoxin; were released for use by forward-deployed commandos during the 1990-91 Persian Gulf War. Of even more concern is the history of massive biologic weapons development in Russia; the agents purportedly stockpiled included Bacillus anthracis, variola virus (smallpox), various viral hemorrhagic fever agents; and a variety of nontraditional agents.
The variola virus causing smallpox was considered eradicated in 1981. It is now stored in two laboratories, one in the United States and one in Russia. This virus is extremely infectious by aerosol route, is readily transmissible from person to person, is stable, and produces relatively high mortality. As a result of waning or nonexistent human immunity to the virus, the inadequacy of current vaccine stockpiles; the variola virus is considered as possible biowarfare and bioterrorism agent. There is a pressing need to be prepared against the possibility of a bio-terrorist attack; but making the decision to be vaccinated is difficult and should not be made without a full understanding of the potential risks involved in receiving the smallpox vaccine.
In an unannounced attack, the detection and identification of the agents would not take place until after the patients begin to present in the emergency department and physician offices. Many health care providers lack clinical experience with most of the agents that could be used as weapons. If terrorists are using the unknown agents or are not limited to use of a single agent, clusters of patients may present in the emergency room with similar symptoms, but different illnesses (Veenema, & Toke, 2006).
Smallpox is a highly contagious viral disease, characterized by fever, malaise, rigors, vomiting, headache, backache, and a vesicular, pastular rash. Patients, in whom smallpox is suspected, as well as close contacts, must be placed in strict quarantine with respiratory isolation for 17 days. PCR and ELISA are the most useful assays.
Anthrax is a zoonatic disease that most often affects cattle, sheep, goats, pigs and horses, caused by the bacterium Bacillus anthracis. Humans most often acquire it cutaneous (a break in the skin), gastrointestinal and by pulmonary inhalations (wool sorter’s disease). The cutaneous form begins with a reddish brown lesion that ulcerates and then forms a dark scab. The signs and symptoms that follow include internal hemorrhage, muscle pain, headache, fever, malaise and fatigue, nausea and vomiting. The pulmonary form is often fatal unless treated early. Treatment is fluoroquinolones and doxycycline. A vaccine is available. PCR and ELISA assay for anthrax are available from natural reference laboratories.
Plaque caused by Yersinia pestis, is a zoonotic disease, and rodents are the primary reservoir. Plaque can present a bubonic, pneumonic, or primary septemic disease. Pneumonic plaque is characterized by acute onset of malaise, high fever, chills, and cough, with initially watery and then bloody sputum. The disease progresses rapidly, producing dyspnea, stridor, and cyanosis, and septic shock; the time from clinical onset to death are usually 4 to 5 days. Streptomycin, gentamycin, tetracycline, fluoroquinolones, and chloramphenicol may be effective; all persons entering the patient’s room should wear a surgical-style mask, as should the patient whenever leaving the room.
Tularemia (deer fly fever, rabbit fever) is an infectious disease of animals caused by the bacillus Francisella (Pasturella) tularensis, which may be transmitted by insect vectors, infected rabbits or direct contact. It is characterized in humans by fever, headache, ulceroglandular and typhoidal disease, or by eye infection, gastrointestinal ulcerations, or pneumonia, depending on the site of entry, virulence of the particular organism, and the response of the host. Treatment includes streptomycin and gentamycin. Recovery produces lifelong immunity and a vaccine is available.
Ricin is a potent toxin from castor beans (Ricinus communis) that produces agglutination of red blood cells and inflammation and hemorrhage of the respiratory and gastrointestinal mucosa. The aerosol route is most hazardous. Symptoms include fever, tightness in the chest, cough, dyspnea, nausea, and arthralgias. In contrast to anthrax respiratory syndrome, ricin toxicity does not produce mediastinitis. The rapidly progressing pulmonary syndrome is not responsive to antibiotics. Gastrointestinal decontamination is warranted in cases of ricin ingestion; most cases occur in children.
Viral hemorrhagic fever is a group of viral aerosol infections, that often occur in specific geographic areas. Ebola virus disease is an infection caused by a species of ribonucleic acid viruses of the Filovirus genus. The usually lethal disease is characterized by hemorrhage and fever. Initial symptoms include fever, headache, chills, myalgia, and malaise; later symptoms include severe abdominal pain, vomiting and diarrhea; maculopapular rash may also occur; bleeding from the nose, eyes and ears. Destruction of internal organs quickly follows. There is no known treatment, and a very high fatality. The Ebola virus is related to the Marburg virus. Marburg virus disease, caused by the Marburg virus, is a severe febrile disease characterized by rash, hepatitis, pancreatitis, and severe gastrointestinal hemorrhage. The disease may be transmitted to hospital personnel by improper handling of contaminated needles or from hemorrhagic lesions of patients; there is no effective treatment.
Emerging infectious diseases is a global phenomenon. During the last decades a large number of new infectious agents and species have been identified and even older previously known viruses have been detected in parts of the globe far from where they originated. Examples are HIV (AIDS), A Streptococcus infection (toxic shock syndrome), Helicopter pylori (peptic ulcer), Borrelia burgdoferii (Lyme disease), the coronavirus SARS, West Nile virus, Hantavirus and Ebola hemorrhagic fever. There are many causes, including evolution and adaptation, an increase in international travel, legal and illegal human transportation and emigration, illegal shipment of potentially infected animals and birds; the incubation of some of these viruses may be longer than it takes to fly from one part of the world to another.
Acquired immune deficiency syndrome (AIDS), recognized by CDC in 1981, is a disease of the human immune system caused by the human immunodeficiency virus (HIV), and now a pandemic. In 2009, it was estimated that there are 33.3 million people worldwide living with HIV/AIDS, with 2.6 million new HIV infections each year and 1.8 million annual deaths due to AIDS (Worldwide Aids & HIV Statistics, 2009). Although antiretroviral treatments can slow the course of the disease, there is no known cure or vaccine.
Severe acute respiratory syndrome (SARS), recognized between the months of November 2002 and July 2003, is a respiratory disease in humans which is caused by the SARS associated coronavirus. The outbreak began in the Guandong province of China, and then SARS spread from the Hong Kong province of China to about 37 countries around the world. There were approximately 8,400 cases, and a reported case-fatality rate of 11%, the elderly and those with pre-existing diseases had higher mortality.
Swine influenza (swine flu), outbreak in 2009, is an infection by any one of the several types of swine influenza virus, for example a new strain of influenza A, H1N1 influenza virus. Both seasonal and H1N1 swine flu continue to infect as in 2010-2011, despite the fact that many believe that there is not much flu activity. In severe cases, patients generally begin to deteriorate around three to four days after symptom onset.
Hantavirus is the cause of several different forms of hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome (caused by Sin Nombre virus). The infection begins with flulike symptoms and may be mistaken for other diseases. Most cases have been reported in the western United States, but cases have also been found in New York City suburbs.
West Nile virus is a single-stranded RNA flavivirus. The infection mostly occur by the bite of an infected mosquito, especially Culex mosquitoes, but may also occur through blood transfusion, transplantation, transplacentally from mother to child, probably through breast feeding, and direct inoculation. Clinically, there are no discernable symptoms in about 80% of those infected, and development of West Nile fever, a mild illness with flu-like symptoms (self-limited in immunocompetent individuals) in approximately 20% of those infected. Development of central nervous system infection (usually encephalitis or meningitis) manifesting neurological signs and symptoms, occurs in less than 1% of the infected. No specific treatment for West Nile virus is available, but health care providers should be able to inform and educate about protective measures (Lashley, 2006).
Microbial evolution resulting in a change of virulence or other characteristics, for example Escherichia coli by O157:H7 having the ability to cause severe illness and hemolytic uremic syndrome (HUS). An outbreak of enterohemorrhagic Escherichia coli (EHEC) in Germany in May 2011, linked to the consumption of locally-grown bean sprouts, that has killed 50 people and made ill nearly 4,050 across Europe, and even in the United States and Canada raises questions about what risks the infection continues to pose and what fallout it will cause. For the first time, on June 28, 2011, a Swede with no connections to Germany has been infected with the virulent E. coli bacteria.
Known diseases that have markedly increased in incidence are, for example diphtheria and pertussis especially in nations with deteriorating public health infrastructure. Organisms have also been deliberately altered to cause intentional harm such as weaponised Bacillus anthracis, in 2001. The appearance of a growing number of multidrug-resistant organisms is of great concern. Microorganisms found to be resistant to antimicrobial agents, including multidrug-resistant tuberculosis (MDR-TB), vancomycin-resistant enterococci (VRE), and methicillin-resistant Staphylococcus aureus (MRSA). Surveillance studies to carefully monitoring increased risk and changing trends for colonization with multidrug-resistant pathogens are mandatory.
Potential exposure to biological agents occurs through, for example, direct contact with a hazardous substance, liquid (droplets or aerosols), inhalation of vapors and aerosols, and ingestion. Health care providers can avoid exposure to biological hazardous agents, by establishing isolation precautions, wearing personnel protective equipment when treating and caring for potentially infected patients (for example, total encapsulating, chemical-resistant suit with self-contained breathing apparatus, gloves, and boots; airtight protection, mask, latex gloves (mouth and eye protection is used as necessary).
Biological terrorism (biological hazardous agents) should be addressed according to the usual HAZMAT protocols in terms of command and control. They are also crime scenes that must be investigated by police or security agencies. Casualty management include: mass medication (exposure management, prophylaxis when indicated); mass treatment by providing various levels of medical and nursing care for those affected by the agent (infection control, laboratory testing); medical transportation; and casualty coordination. Place clothing from suspected victims in airtight plastic bags and save for law authorities (FBI, SBI).
Infection control measures of patients with multidrug-resistant organisms: Place patients in single rooms or groups with other infected patients. Wear a gown and gloves. Dedicate equipment to individual patients. Consider the need for focused culturing (environment and staff); and perform surveillance culturing of patients who were roommates before the infection was detected. Isolation until negative culture from multiple sites. Be careful with transfers and flag the permanent medical records, so patients can be identified and promptly isolated if readmitted. Implement surveillance of multidrug-resistant organisms to promote early detection, incidence rates, and asymptomatic colonization. Implement contact precautions for patients infected or colonized with a multidrug-resistant organism (gown, gloves, a private room is preferred, dedicated equipment, and enhanced environmental cleaning).
If you suspect a release of an unknown biological substance: Leave the area right away, cover your mouth and nose (allow breathing). Take off your clothes; seal them tightly in a plastic bag. Take a shower or wash your skin and hair well with soap and water, put on clean clothes, seek medical care, and call the police if they are not aware of the biological emergency, as they will take steps to help people avoid getting sick. Information to the public: Risk factors and contributing factors for gastroenteritis include ingestion of contaminated food and water; bacteria, viruses, or parasites; allergy or intolerance of specific food; drug reactions; direct or indirect fecal-oral transmission from an infected person; poor sanitation conditions; crowded living conditions; and travel to a foreign country.
Report identified cases or events to the public health system to facilitate surveillance and investigation (using the established protocols). Acknowledge the patient’s concerns, allow the patient to express feelings about the accident, explain hospital procedures, give emotional support and clear concise explanations and repeat them often. Encourage the patient and close ones to ask questions.