The following are pre-publication drafts of articles from the Morbidity and Mortality Weekly Report dated June 30, 1995. Late-breaking articles, and final editorial revisions are not included; therefore, these articles should be considered preliminary, and not to be released to the public. --CDC -------------------------------------------------------------- Heat-Related Illnesses and Deaths -- United States, 1994-1995 Although heat-related illness and death are readily preventable, exposure to extreme temperatures causes at least 240 deaths* during years with no heat wave. A heat wave is defined by the National Weather Service as greater than or equal to 3 consecutive days of temperatures greater than or equal to 90.0 F (greater than or equal to 32.2 C). In 1980, 1983, and 1988 (recent years with prolonged heat waves), 1700, 556, and 454 deaths, respectively, were attributed to heat. This report describes four instances of heat-related illness and death that occurred in the United States during 1994 and 1995 and summarizes risk factors for heat-related illness and death. Case 1. On June 13, 1994, in Houston, Texas, a 29-year-old mentally impaired women was found lying on the floor of her garage. She was unresponsive when admitted to a local hospital and had a rectal temperature of 107.9 F (41.9 C). She died within 2 days of arrival at the hospital. The outdoor temperature and humidity had reached 92.0 F (33.3 C) and 91%, respectively. Her underlying cause of death was listed as hyperthermia**. Case 2. On June 18, 1994, in St. Louis, Missouri, a 68-year-old woman who weighed approximately 350 pounds complained of "feeling ill" at 11 p.m. Her spouse phoned paramedics, who found her unresponsive; cardiac rhythm was undetectable after she was placed in the ambulance. At 11:38 p.m., she was pronounced dead on arrival at the emergency department with a rectal temperature of 108.9 F (42.7 C). Her home air conditioning system was operational but had not been used. The outdoor temperature and humidity that day had reached 95.0 F (35.6 C) and 45%, respectively. Her cause of death was listed as hyperthermia, with morbid obesity listed as an "other condition." Case 3. On July 1, 1994, in Tucson, Arizona, a 44-year-old woman, her 53-year-old brother (both mentally retarded), and their 72-year-old mother were found dead in their home by neighbors after they had not been seen for several days. The coroner's report indicated that the mother died first, and the children had remained in the house until they also died. There was no air conditioner in the house, and all windows were closed. The outdoor temperature and humidity had reached 106.0 F (41.1 C) and 36%, respectively. The cause of death for all three was listed as hyperthermia due to heat exposure. Case 4. On June 26, 1995, in College Park, Georgia, a grocery store customer found a 6-year-old boy, a 4-year-old girl, and a 2-year-old boy in a locked car with the windows closed in the store parking lot. After unsuccessfully attempting to attract the children's attention, the customer called 911. Police and paramedics were able to get the 6-year-old to unlock the car door. Paramedics reported the children were unresponsive, disoriented, flushed, and profusely sweating and had delayed reflexes. The children were placed in the shade under a tree and given juice and water for rehydration; they regained alertness and began talking within 30 minutes. The children had been in the car for approximately 10-20 minutes. The outdoor temperature and humidity were 84.0 F (28.9 C) and 60%, respectively, and the estimated temperature inside the car was greater than or equal to 110.0 F (greater than or equal to 43.3 C). Paramedics reported that the children had classic signs of the onset of heatstroke that would have been life-threatening within 5-10 minutes. Reported by: C Anders, JA Jachimczyk, Forensic Center, Harris County Medical Examiner, Houston, Texas. R Green, Medical Examiner's Office, St. Louis, Missouri. B Parks, Forensic Science Center, Tucson, Arizona. D Miller, Western Regional Climate Center, Reno, Nevada. LB Harper, College Park Police Dept, CT Dillard, ER Evans, College Park Fire Dept, College Park, Georgia. Health Studies Br and Surveillance and Programs Br, Div of Environmental Hazards and Health Effects, National Center for Environmental Health, CDC. Editorial Note: Each year 148-1700 persons die in the United States because of excessive exposure to high temperatures. The highest age-adjusted death rates for heat-related illness have occurred in Alabama, Arkansas, Arizona, Georgia, Kansas, Mississippi, Missouri, Oklahoma, and South Carolina (from one to six per 1 million persons per year during 1979-1992). However, deaths listed with an underlying cause of hyperthermia represent only a portion of heat-related excess mortality because increased mortality from cardiovascular, cerebrovascular, and respiratory causes also occurs during heat waves (1-4). Heatstroke, the most serious heat-related illness, is a medical emergency characterized by a body temperature greater than or equal to 105.0 F (greater than or equal to 40.6 C) and may include symptoms such as disorientation, delirium, and coma. Onset of heatstroke can be rapid with progression to life-threatening illness within minutes. Heat exhaustion is a milder form of heat- related illness that can develop following exposure for several days to high ambient temperatures and inadequate or unbalanced replacement of fluids and electrolytes. Heat exhaustion is characterized by dizziness, weakness, and fatigue and may be sufficiently severe to require hospitalization. The cases described in this report underscore the increased risk for heat-related illness and death among the very young (particularly infants), the elderly (i.e., persons aged greater than or equal to 65 years) (Figure 1), and persons with impaired mobility (5). In addition, persons with chronic illness (e.g., cardiovascular disease) are at increased risk. Persons in these groups may be unable to obtain adequate fluids or to remove themselves from hot environments (e.g., closed automobiles). In extremely hot environments, the body is unable to cool itself through sweating. The risk for heat-related illness and death also may be higher among persons who use certain drugs (1), including neuroleptics (e.g., haloperidol or chlorpromazine), which impair thermoregulatory function; medications with anticholinergic effects (e.g., medication for Parkinson disease), which inhibit perspiration; and major tranquilizers (e.g., phenothiazines, butyrophenones, and thiozanthenes). In addition, excessive alcohol consumption can cause dehydration and may be a predisposing factor in heat-related illness (5). Salt tablets are not recommended and are potentially dangerous (1). Persons whose fluid consumption is restricted for medical reasons or who use diuretic medications should not alter their fluid intake patterns without the advice of their physicians. The risk for illness and death also may be increased in persons who are unacclimatized to the heat and who work or exercise vigorously outdoors, fail to rest frequently, or do not drink sufficient quantities of fluids; acclimatization to warm environments may require gradual exposure to high temperatures for 10-14 days (6). The use of an artificially cooled environment (e.g., air-conditioning or evaporative cooling units), even for a few hours each day, will reduce the risk for heat-related illness (5). Fans can be a source of relief in areas with low humidity. However, because increased air movement (e.g., fans) has been associated with increased heat stress when the ambient temperature exceeds approximately 100 F (37.8 C) and because fans are not protective at temperatures greater than 90 F (greater than 32.2 C) with humidity greater than 35% (the exact temperature varies with the humidity), fans should not be used for preventing heat-related illness in areas of high humidity (5,7). Persons without home air conditioners should be assisted in taking advantage of such environments in private or in public places, such as shopping malls. Immersion in cool water (59.0 F- 61.0 F [15.0 C-16.1 C]) also can be used for maintaining acceptable body temperature. References 1. Kilbourne EM. Heat waves. In: The public health consequences of disasters (CDC monograph). Atlanta: US Department of Health and Human Services, Public Health Service, CDC, 1989;51-61. 2. CDC. Heat-related deaths--Philadelphia and United States, 1993-1994. MMWR 1994;43:453-5. 3. Jones TS, Liang AP, Kilbourne EM, et al. Morbidity and mortality associated with the July 1980 heat wave in St. Louis and Kansas City, Mo. JAMA 1982;247:3327-31. 4. Buchanan S, Wainwright S, Robinson L, Potryzbowski P, Parrish R, Sinks T. Heat-related mortality in five metropolitan east coast counties, 1993 [Abstract]. In: Program and abstracts of the 1995 Epidemic Intelligence Service Conference. Atlanta: US Department of Health and Human Services, Public Health Service, CDC, 1995. 5. Kilbourne EM, Choi K, Jones TS, Thacker SB, and the Field Investigation Team. Risk factors for heatstroke: a case-control study. JAMA 1982;247:3332-6. 6. Williams CG, Bredell, GA, Wyndham CH, et al. Circulatory and metabolic reactions to work in the heat. J Appl Physiol 1962;17:625-38. 7. Lee DH. Seventy-five years of searching for a heat index. Environ Res 1980;22:331-56. *During 1979-1992, a total of 5379 deaths in the United States were attributed to excessive heat, classified according to the International Classification of Diseases, Ninth Revision (ICD-9), as E900.0, "due to weather conditions"; E900.1, "of man-made origin"; or E900.9, "of unspecified origin." These data were obtained from CDC's Compressed Mortality File (CMF), which contains information from death certificates filed in the 50 states and the District of Columbia that have been prepared in accordance with external cause codes. CDC's Wide-ranging ONline Data for Epidemiologic Research computerized information system was used to access CMF data. **Hyperthermia is the diagnostic term used for deaths resulting from core body temperature greater than or equal to 105 F (greater than or equal to 40.6 C). Update: Outbreak of Ebola Viral Hemorrhagic Fever -- Zaire, 1995 As of June 25, public health authorities have identified 296 persons with viral hemorrhagic fever (VHF) attributable to documented or suspected Ebola virus infection in an outbreak in the city of Kikwit and the surrounding Bandundu region of Zaire (1,2); 79% of the cases have been fatal, and 90 (32%) of 283 cases in persons for whom occupation was known occurred in health-care workers. This report summarizes characteristics of persons with VHF from an initial description of cases and preliminary findings of an assessment of risk factors for transmission. A case was defined as confirmed or suspected VHF in a resident of Kikwit or the surrounding Bandundu region identified since January 1. The median age of persons with VHF was 37 years (range: 1 month-71 years); 52% were female. Based on preliminary analysis of 66 cases for which data were available, the most frequent symptoms at onset were fever (94%), diarrhea (80%), and severe weakness (74%); other symptoms included dysphagia (41%) and hiccups (15%). Clinical signs of bleeding occurred in 38% of cases. Potential risk factors for intrafamilial transmission were evaluated for secondary cases within households of 27 primary household cases identified through May 10. A primary household case was defined as the first case of VHF in a household; household was defined as persons who shared a cooking fire at the onset of illness in the primary household case. Among 173 household members of the 27 primary household cases, there were 28 (16%) secondary case-patients. The risk for developing VHF was higher for spouses of the primary household case-patients than for other household members (10 [45%] of 22 compared with 18 [14%] of 151; rate ratio [RR]=3.8; 95% confidence interval [CI]=2.0-7.2) and for adults (aged greater than or equal to 18 years) than for children (24 [30%] of 81 compared with four [4%] of 92; RR=6.7; 95% CI=2.4-18.4). Needle sticks or surgical procedures during the 2 weeks before illness were reported for two of the 27 primary household case-patients and none of 28 secondary case-patients. Of the 28 secondary case-patients, 12 had direct contact with blood, vomitus, or stool of the ill person during hospitalization (i.e., later stages of illness), and 17 simultaneously shared the same hospital bed. Of 78 household members who had no direct physical contact with the person with the primary household case-patient during their clinical illness, none developed VHF (95% CI=0-4). Reported by: M Musong, MD, Minister of Health, Kinshasa; T Muyembe, MD, Univ of Kinshasa; Technical and Scientific International Coordinating Committee for Viral Hemorrhagic Fever, Kikwit, Zaire. World Health Organization Kinshasa, Zaire. World Health Organization, Brazzaville, Congo. World Health Organization, Geneva, Switzerland. Medecins Sans Frontieres, Belgium. Epicentre, Paris, France. Prince Leopold Institute of Tropical Medicine and Hygiene, Antwerp, Belgium. Div of Viral and Rickettsial Diseases, National Center for Infectious Diseases; International Health Program Office; Epidemiology Program Office, CDC. Editorial Note: The incidence of VHF related to Ebola virus in Kikwit has diminished following the institution of interventions including 1) training of medical and relief personnel on the proper use of protective equipment, 2) initiation of aggressive case-finding; and 3) educational measures in the community (e.g., pamphlets and public announcements) (1,2). However, cases continue to occur, and each case has the potential to be a source for additional infections. Therefore, ongoing measures including continued intensive surveillance, training activities, and public education are necessary to contain the epidemic. To maximize prevention and control measures, prompt laboratory diagnosis is an important component of surveillance. An enzyme-linked immunosorbent assay (ELISA) detected Ebola antigen in specimens initially submitted to CDC from 11 of 13 acutely infected persons (1). Ongoing testing of additional specimens will assess the utility of this ELISA as a rapid diagnostic test that could be used locally. In addition, Ebola antigen was detected in multiple formalin-fixed tissue samples (liver, lung, and skin) of seven case-patients by immunohistochemical (IHC) staining using a specific polyclonal antibody. These findings suggest that IHC staining of fixed tissue may assist in surveillance for hemorrhagic fevers in Africa and other countries. Other activities include ecologic studies to identify the natural reservoir of the virus; these studies are focusing especially on mammals, nonmammalian vertebrates, and arthropods. Transmission associated with health-care providers and caregivers has been a prominent feature of the current and previous VHF outbreaks in Africa attributable to Lassa, Marburg, Ebola, or Crimean-Congo hemorrhagic fever viruses (3). In some outbreaks, transmission from patient to patient within hospitals has been associated with the reuse of unsterile needles and syringes. As in previous outbreaks, high rates of transmission in this outbreak have occurred from patients to health-care workers and to family members who provided nursing care without appropriate barrier precautions to prevent exposure to blood, other body fluids, vomitus, urine, and stool. Based on findings in this report, the risk for transmitting infection from patients appears to be highest during the later stages of illness, which is characterized by vomiting, diarrhea, shock, and often hemorrhage. However, a small number of cases of VHF in Zaire have been reported in family members whose only contact with an infected person was in the domestic setting within a few days after onset of illness. Updated recommendations for the management of VHFs attributable to these viruses in the United States are presented in a Notice to Readers in this issue (4). References 1. CDC. Outbreak of Ebola viral hemorrhagic fever--Zaire, 1995. MMWR 1995;44:381-2. 2. CDC. Update: outbreak of Ebola viral hemorrhagic fever--Zaire, 1995. MMWR 1995;44:399. 3. CDC. Management of patients with suspected viral hemorrhagic fever. MMWR 1988;37(no. S-3):1-15. 4. CDC. Update: management of patients with suspected viral hemorrhagic fever--United States. MMWR 1995;44:475-79. Notice to Readers Update: Management of Patients with Suspected Viral Hemorrhagic Fever -- United States In 1988, CDC published guidelines for managing patients with suspected viral hemorrhagic fever (VHF) (1). Pending a comprehensive review of the 1988 guidelines, this notice provides interim recommendations that update the 1988 guidelines for health-care settings in the United States. This update applies to four viruses that cause syndromes of VHF: Lassa, Marburg, Ebola, and Congo-Crimean hemorrhagic fever viruses; although the risk and/or mode of nosocomial transmission differs for each of these viruses, the limited data do not permit clear distinctions. Background In Africa, transmission of VHF has been associated with reuse of unsterile needles and syringes and with provision of patient care without appropriate barrier precautions to prevent exposure to virus-containing blood and other body fluids (including vomitus, urine, and stool). The risks associated with various body fluids have not been well defined as most caregivers who acquired infection had multiple contacts with multiple fluids. Epidemiologic studies of VHF in humans indicate that infection is not readily transmitted from person to person by the airborne route (1,2). Airborne transmission involving humans has never been documented and is considered a possibility only in rare instances from persons with advanced stages of disease (e.g., one patient with Lassa fever who had extensive pulmonary involvement may have transmitted infection by the airborne route) (3). In contrast, investigation of VHF in nonhuman primates (i.e., monkeys) has suggested possible airborne spread among these species (4-7). Despite uncertainties regarding the applicability to humans of data regarding airborne transmission in nonhuman primates, such information must be considered in the development of infection-control precautions because information regarding exposure and transmission in humans is limited. The risk for person-to-person transmission of hemorrhagic fever viruses is highest during the latter stages of illness, which are characterized by vomiting, diarrhea, shock, and often hemorrhage. VHF infection has not been reported in persons whose contact with an infected patient occurred only during the incubation period (i.e., before the patient became febrile; the incubation period ranges from 2 days to 3 weeks, depending on the etiology of the VHF [1]). In the 1995 Zaire outbreak, some instances of Ebola virus transmission within a few days after onset of fever were reported; however, other symptoms in the source patients and the level of exposure to body fluids among these secondary cases were unknown (CDC, unpublished data, 1995). In studies involving three monkeys experimentally infected with Ebola virus (Reston strain), fever and other systemic signs of illness preceded detection of infectious virus in the pharynx by 2-4 days, in the nares by 5-10 days, in the conjunctivae by 5-6 days, and on anal swabs by 5-6 days (P. Jahrling, U.S. Army Medical Research Institute of Infectious Diseases, unpublished data, 1995). Reporting All suspected cases of infection with Ebola virus and other hemorrhagic fever viruses should be reported immediately to local and state health departments and to CDC (telephone [404] 639-1511; from 4:30 p.m. to 8 a.m., telephone [404] 639-2888). Specimens for virus-specific diagnostic tests should be sent to CDC as rapidly as possible according to instructions provided when contact is made. General information regarding Ebola virus infection is available through the CDC Ebola Hotline (telephone [800] 900-0681). Recommendations The following recommendations apply to patients who, within 3 weeks before onset of fever, have either 1) traveled in the specific local area of a country where VHF has recently occurred; 2) had direct contact with blood, other body fluids, secretions, or excretions of a person or animal with VHF; or 3) worked in a laboratory or animal facility that handles hemorrhagic fever viruses. The likelihood of acquiring VHF is considered extremely low in persons who do not meet any of these criteria. The cause of fever in persons who have traveled in areas where VHF is endemic is more likely to be a different infectious disease (e.g., malaria or typhoid fever); evaluation for and treatment of these other potentially serious infections should not be delayed. 1. Because most ill persons undergoing prehospital evaluation and transport are in the early stages of disease and would not be expected to have symptoms that increase the likelihood of contact with infectious body fluids (e.g., vomiting, diarrhea, or hemorrhage), universal precautions are generally sufficient (8). If a patient has respiratory symptoms (e.g., cough or rhinitis), face shields or surgical masks and eye protection (e.g., goggles or eyeglasses with side shields) should be worn by caregivers to prevent droplet contact (8). Blood, urine, feces, or vomitus, if present, should be handled as described in the following recommendations for hospitalized patients. 2. Patients in a hospital outpatient or inpatient setting should be placed in a private room. A negative pressure room is not required during the early stages of illness, but should be considered at the time of hospitalization to avoid the need for subsequent transfer of the patient. Nonessential staff and visitors should be restricted from entering the room. Caretakers should use barrier precautions to prevent skin or mucous membrane exposure to blood and other body fluids, secretions, and excretions. All persons entering the patient's room should wear gloves and gowns to prevent contact with items or environmental surfaces that may be soiled. In addition, face shields or surgical masks and eye protection (e.g., goggles or eyeglasses with side shields) should be worn by persons coming within approximately 3 feet of the patient to prevent contact with blood, other body fluids, secretions (including respiratory droplets), or excretions. The need for additional barriers depends on the potential for fluid contact, as determined by the procedure performed and the presence of clinical symptoms that increase the likelihood of contact with body fluids from the patient (8). For example, if copious amounts of blood, other body fluids, vomit, or feces are present in the environment, leg and shoe coverings also may be needed. Before entering the hallway, all protective barriers should be removed and shoes that are soiled with body fluids should be cleaned and disinfected as described below (see recommendation 6). An anteroom for putting on and removing protective barriers and for storing supplies would be useful, if available (1). 3. For patients with suspected VHF who have a prominent cough, vomiting, diarrhea, or hemorrhage, additional precautions are indicated to prevent possible exposure to airborne particles that may contain virus. Patients with these symptoms should be placed in a negative-pressure room (9). Persons entering the room should wear personal protective respirators as recommended for care of patients with active tuberculosis (high efficiency particulate air [HEPA] respirators or more protective respirators) (9). 4. Measures to prevent percutaneous injuries associated with the use and disposal of needles and other sharp instruments should be undertaken as outlined in recommendations for universal precautions (8). If surgical or obstetric procedures are necessary, the state health department and CDC's National Center for Infectious Diseases, Hospital Infections Program (telephone [404] 639-6425) and Division of Viral and Rickettsial Diseases (telephone [404] 639-1511; from 4:30 p.m. to 8 a.m., telephone [404] 639-2888) should be consulted regarding appropriate precautions for these procedures. 5. Because of the potential risks associated with handling infectious materials, laboratory testing should be the minimum necessary for diagnostic evaluation and patient care. Clinical laboratory specimens should be obtained using precautions outlined above (see recommendations 1-4 above), placed in plastic bags that are sealed, then transported in clearly labeled, durable, leakproof containers directly to the specimen handling area of the laboratory. Care should be taken not to contaminate the external surfaces of the container. Laboratory staff should be alerted to the nature of the specimens, which should remain in the custody of a designated person until testing is done. Specimens in clinical laboratories should be handled in a class II biological safety cabinet following biosafety level 3 practices (10). Serum used in laboratory tests should be pretreated with polyethylene glycol p-tert-octylphenyl ether (Triton(R) X-100)*; treatment with 10 uL of 10% Triton(R) X-100 per 1 mL of serum for 1 hour reduces the titer of hemorrhagic fever viruses in serum, although 100% efficacy in inactivating these viruses should not be assumed. Blood smears (e.g., for malaria) are not infectious after fixation in solvents. Routine procedures can be used for automated analyzers; analyzers should be disinfected as recommended by the manufacturer or with a 500 parts per million solution of sodium hypochlorite (1:100 dilution of household bleach: 1/4 cup to 1 gallon water) after use. Virus isolation or cultivation must be done at biosafety level 4 (10). The CDC mobile isolation laboratory is no longer available (1). 6. Environmental surfaces or inanimate objects contaminated with blood, other body fluids, secretions, or excretions should be cleaned and disinfected using standard procedures (8). Disinfection can be accomplished using a U.S. Environmental Protection Agency (EPA)-registered hospital disinfectant or a 1:100 dilution of household bleach. 7. Soiled linens should be placed in clearly labeled leak-proof bags at the site of use and transported directly to the decontamination area. Linens can be decontaminated in a gravity displacement autoclave or incinerated. Alternatively, linens can be laundered using a normal hot water cycle with bleach if universal precautions to prevent exposures are precisely followed (8) and linens are placed directly into washing machines without sorting. 8. There is no evidence for transmission of hemorrhagic fever viruses to humans or animals through exposure to contaminated sewage; the risk of such transmission would be expected to be extremely low with sewage treatment procedures in use in the United States. As an added precaution, however, measures should be taken to eliminate or reduce the infectivity of bulk blood, suctioned fluids, secretions, and excretions before disposal. These fluids should be either autoclaved, processed in a chemical toilet, or treated with several ounces of household bleach for greater than or equal to 5 minutes (e.g., in a bedpan or commode) before flushing or disposal in a drain connected to a sanitary sewer. Care should be taken to avoid splashing when disposing of these materials. Potentially infectious solid medical waste (e.g., contaminated needles, syringes, and tubing) should either be incinerated or be decontaminated by autoclaving or immersion in a suitable chemical germicide (i.e., an EPA-registered hospital disinfectant or a 1:100 dilution of household bleach), then handled according to existing local and state regulations for waste management. 9. If the patient dies, handling of the body should be minimal. The corpse should be wrapped in sealed leakproof material, not embalmed, and cremated or buried promptly in a sealed casket. If an autopsy is necessary, the state health department and CDC should be consulted regarding appropriate precautions (1). 10. Persons with percutaneous or mucocutaneous exposures to blood, body fluids, secretions, or excretions from a patient with suspected VHF should immediately wash the affected skin surfaces with soap and water. Application of an antiseptic solution or handwashing product may be considered also, although the efficacy of this supplemental measure is unknown. Mucous membranes (e.g., conjunctiva) should be irrigated with copious amounts of water or eyewash solution. Exposed persons should receive medical evaluation and follow-up management (1). Reported by: Hospital Infections Program, Div of Viral and Rickettsial Diseases, and Div of Quarantine, National Center for Infectious Diseases; Office of the Director, National Institute for Occupational Safety and Health; Office of Health and Safety, CDC. References 1. CDC. Management of patients with suspected viral hemorrhagic fever. MMWR 1988;37 (no. S-3):1-15. 2. Baron RC, McCormick JB, Zubeir OA. Ebola virus disease in southern Sudan: hospital dissemination and intrafamilial spread. Bull WHO 1983;61:997-1003. 3. Carey DE, Kemp GE, White HA, et al. Lassa fever: epidemiological aspects of the 1970 epidemic, Jos, Nigeria. Trans R Soc Trop Med Hyg 1972;66:402-8. 4. Dalgard DW, Hardy RJ, Pearson SL, et al. Combined simian hemorrhagic fever and Ebola virus infection in cynomolgus monkeys. Lab Anim Sci 1992;42:152-7. 5. CDC. Update: filovirus infections among persons with occupational exposure to nonhuman primates. MMWR 1990;39:266-7. 6. Johnson E, Jaax N, White, Jahrling P. Lethal experimental infection of rhesus monkeys by aerosolized Ebola virus. Int J Exp Pathol (in press). 7. Pokhodynev VA, Gonchar NI, Pshenichnov VA. Experimental study of Marburg virus contact transmission. Vopr Virusol 1991;36:506-8. 8. CDC. Guidelines for prevention of transmission of human immunodeficiency virus and hepatitis B virus to health-care and public safety workers. MMWR 1989;38:(no. S-6):1-37. 9. CDC. Guidelines for preventing the transmission of Mycobacterium tuberculosis in health-care facilities. MMWR 1994;43(no. RR-13):33-34, 71-81. 10. CDC/National Institutes of Health. Biosafety in microbiological and biomedical laboratories. 3rd ed. Atlanta, Georgia: US Department of Health and Human Services, Public Health Service, 1993; DHHS publication no. (CDC)93-8395. * Use of trade names and commercial sources is for identification only and does not imply endorsement by the Public Health Service or the U.S. Department of Health and Human Services. Notice to Readers Prevention 96 Conference: Prevention for All -- Challenges, Opportunities, and Strategies Prevention 96, the 13th annual national preventive medicine meeting, will be sponsored by the American College of Preventive Medicine and the Association of Teachers of Preventive Medicine in collaboration with CDC and other national health agencies in Dallas, Texas, March 23-26, 1996. The conference will explore challenges, opportunities, and strategies for preventive medicine in the health-care system. Information on registration and submission of abstracts is available from the Meetings Manager, Prevention 96, 1660 L Street, N.W., Suite 206, Washington, DC, 20036-5603; telephone (202) 466-2569. Erratum: Vol. 44, No. SS-2 In the CDC Surveillance Summaries, on page 29 of the report titled "Abortion Surveillance--United States, 1991," the ninth footnote to Table 3 should read: *** greater than 100 abortions per 1,000 women 15-44 years of age. Erratum: Vol. 44, No. 23 In the article "Implementation of Health Initiatives During a Cease Fire--Sudan, 1995" one of the areas in Figures 1 (page 434) and 2 (page 435) was mislabeled. In Figure 1, the area labeled "Red Sea" should have been labeled Red Sea state. In Figure 2, the area labeled "Red Sea" should not have been labeled.