Hypothermia-Related Deaths—Virginia, November 1996-April 1997 FREE

MMWR. 1997;46:1157-1159

1 figure omitted

HYPOTHERMIA is defined as a central or core body temperature of ≤95 F (≤35 C) and is a medical emergency.¹ Persons with hypothermia are at high risk for death.² Although hypothermia-related deaths are common during winter months in states characterized by cold winters (e.g., Alaska and North Dakota) and with mountainous or desert terrain (e.g., Arizona and New Mexico), hypothermia and associated deaths also occur in states with milder climates. For example, during November 1996-April 1997, the Chief Medical Examiner's Office in Virginia identified 20 deaths caused by hypothermia; of these, 11 (55%) were among men and decedents ranged in age from 22 to 86 years (mean: 63 years). This report describes selected cases of hypothermia-related deaths in Virginia during November 1996-April 1997 and summarizes hypothermia-related deaths in the United States during 1979-1994.

In December 1996, an 80-year-old woman was found lying dead in a ditch near the nursing home in which she resided. The decedent had Alzheimer disease, Parkinson disease, and congestive heart failure and had been reported missing from the nursing home approximately 12 hours earlier. She was fully clothed, and an autopsy indicated no evidence of life-threatening trauma, preexisting infection, or new intracranial hemorrhage. The outside temperature during the period she was presumed to be outside was approximately 40 F (4 C). There was no detectable blood alcohol. The cause of death was listed as hypothermia attributed to environmental exposure.

In January 1997, a motorist found a 45-year-old woman lying dead in a ditch on the side of a road. The body was fully clothed with the torso immersed in water; there were no signs of lethal trauma. The decedent had last been seen alive 3 days earlier, and temperatures during the intervening time had been below freezing. The decedent had a history of alcohol abuse, and an empty wine bottle was found nearby. Her blood alcohol concentration (BAC) was 0.19%; levels were higher in the vitreous humor, indicating that, before death, her BAC had been substantially higher. The cause of death was listed as hypothermia attributed to exposure to environmental cold.

In February 1997, an 83-year-old man was found dead in his home. He had no known history of medical problems. He was partially dressed, and there were no signs of traumatic injury. The temperatures during the preceding days had been below freezing, and there was no heat in the house. The cause of death was listed as exposure to cold.

M Fierro, MD, Office of the Chief Medical Examiner; SR Jenkins, VMD, State Epidemiologist, Virginia Dept of Health. Health Studies Br, Div of Environmental Hazards and Health Effects, National Center for Environmental Health, CDC.

From 1979 through 1994, a total of 11,817 deaths were reported in the United States for which hypothermia was the underlying cause (average annual number and rate: 739 and 0.3 per 100,000 population).* For an additional 9720 deaths, injury attributed to cold was listed as a contributing factor.† In nearly half (5769 [49%]) of deaths for which hypothermia was the underlying cause, decedents were aged ≥65 years. In every age group, the hypothermia-related death rate for males exceeded that for females; for persons aged ≥65 years, the rate for men was more than double that for women (1.8 versus 0.8). In addition, for persons aged ≥65 years, the death rate for men of black and other races was 6.4 and for white men was 1.4. For women of black and other races, the death rate was 2.5 compared with 0.7 for white women.‡ Race-specific differences may have reflected variations in socioeconomic determinants for factors such as access to protective clothing, shelter, and medical care.

In settings of cold exposure, the risk for developing hypothermia is greatest among the elderly, persons who are homeless or mentally ill, outdoor workers, trauma victims, and persons with serious medical conditions (e.g., cardiovascular disease, adrenal disease, and hypothyroidism).^1,2 Other risk factors include excessive alcohol use, exhaustion, poor nutrition, inadequate housing, and drug use (e.g., sedatives, anxiolytics, phenothiazines, and tricyclic antidepressants).^1-3 Hypothermia can occur when even moderately low ambient temperatures (e.g., as high as 60 F [15.5 C]) overcome a person's ability to conserve heat.²

The prognosis for hypothermia is improved by prompt recognition of the clinical presentation and initiation of treatment. Shivering is an early indication of hypothermia, and a decline in the core temperature can be accompanied by neurologic abnormalities (e.g., amnesia, dysarthria, ataxia, and confusion). Other problems may include hematologic, respiratory, renal, and endocrinologic abnormalities, and severe hypothermia may be characterized by coma, hypotension, apnea, and/or cardiac arrhythmias.^4,5 Because most standard thermometers do not record temperatures below 93 F (34 C), use of special equipment (e.g., cold-recording rectal thermometers) may be required for accurately determining core body temperature.

Public health strategies for reducing the risk for hypothermia include public education and programs targeting high-risk populations. Specific preventive measures include wearing adequate clothing (particularly headgear), maintaining fluid and caloric intake, avoiding fatigue, ensuring heated shelter, and refraining from alcohol consumption. In addition, outreach programs should include providing short-term, specialized emergency medical and social services during periods of extreme cold⁶ and providing shelter to homeless persons. Workers in cold weather should avoid heavy exertion and wear appropriate protective clothing. Because of the importance of adequate housing during winter months, elderly persons or persons with serious underlying medical conditions who live at home should be monitored by family, neighbors, or social service providers.

References: 6 available.

*Data obtained from the Compressed Mortality File maintained by CDC. Hypothermia was defined as the International Classification of Diseases, Ninth Revision (ICD-9), codes E901.0, E901.8, and E901.9 (excludes manmade cold-E901.1).

† Data obtained from CDC's Multiple Cause of Mortality file. Cases defined by ICD-9, codes E901.0, E901.8, and E901.9 and Nature of Injury code 991.

‡Data on race/ethnicity were collected only for white, black, and other races. In this analysis, black and other races are grouped together because rates for other races were too small for stable estimates.

MMWR. 1997;46:994-1000

1 table, 1 figure omitted

IN 1988, the World Health Assembly resolved to eradicate poliomyelitis by 2000; this goal was reaffirmed in 1989 by the World Health Organization (WHO) Regional Committee for Europe. Although most of the 51 member states of the European Region of WHO (EUR) (including Israel and the Central Asian Republics) have reported zero polio cases since at least the early 1980s, endemic transmission or outbreaks of polio continued to be reported through 1996 in some countries. This report updates progress of the EUR polio eradication initiative through September 1997,^1- 2 including progress in polio vaccination activities, interruption of wild poliovirus transmission, and the establishment of sensitive surveillance systems in the region.

In 1995 and 1996, a total of 41 EUR countries routinely used oral poliovirus vaccine (OPV) for infant vaccination, six used inactivated poliovirus vaccine (IPV), and four used sequential IPV-OPV schedules. In 1996, the provisional regional average for coverage with a primary series of polio vaccination by age 1 year was 92% (range: 77%-100%, with 26 countries reporting), compared with 83% in 1993 (range: 45%-100%, with 46 countries reporting); coverage levels in many of the Newly Independent States of the Former Soviet Union reached their lowest points during the economic transitions of the early 1990s.

The third year of an international mass vaccination activity—Operation MECACAR (Eastern Mediterranean, Caucasus, Central Asian Republics)—was completed in May 1997. Operation MECACAR consisted of coordinated National Immunization Days (NIDs)* in the bordering countries of the WHO Eastern Mediterranean and European regions with continuing endemic polio.¹ During each of these NIDs, 58-60 million children (95% of targeted children) received two supplementary doses of OPV. Nine countries of EUR (Armenia, Azerbaijan, Georgia, Kazakhstan, Kyrgyzstan, Tajikistan, Turkey, Turkmenistan, and Uzbekistan) participated in all 3 years of Operation MECACAR. The Russian Federation joined MECACAR in 1996 and 1997. Bulgaria also conducted NIDs in synchrony with Operation MECACAR in 1995. In addition to Operation MECACAR, five other EUR countries at high risk for polio conducted NIDs or sub-NIDs in 1996 (Albania, Republic of Moldova, Romania, Ukraine, and the Federal Republic of Yugoslavia).

Because of a polio outbreak following a wild poliovirus importation into the Balkan peninsula during 1996, extra emergency mass vaccination rounds were conducted during 1996 and/or 1997 in Albania, Bosnia, Croatia (Eastern Slavonia section), the Federal Republic of Yugoslavia, Herzegovina, and The Former Yugoslav Republic of Macedonia. Two rounds of targeted "catch-up" vaccination also were conducted in Greece in 1996 as a result of the epidemic.

By 1996, all 16 EUR member states that had reported epidemic or endemic polio since 1991 had established surveillance for acute flaccid paralysis (AFP), the surveillance strategy recommended by WHO for polio eradication. Fifteen EUR member states without endemic disease also had instituted such systems. A total of 33 member states will be conducting AFP surveillance by the end of 1997. During January 1996-September 30, 1997, six countries (Belarus, Israel, Kazakhstan, Romania, the Russian Federation, and Ukraine) achieved the minimum AFP reporting rate indicative of a sensitive surveillance system (at least one nonpolio AFP case per 100,000 children aged <15 years annually). The regional nonpolio AFP rate increased from 0.3 in 1995 to 0.7 (range: 0-2.2) in 1996; based on cases reported through September 1997, the annualized rate for 1997 was 1.1. The rate of collection of two adequate stool samples† from persons with reported AFP cases increased from 47% in 1995 to 68% in 1996; through September 1997, 78% of reported AFP cases had two adequate specimens. During 1996 and 1997, Armenia, Belarus, Kazakhstan, Kyrgyzstan, Romania, and Turkmenistan consistently achieved the WHO-recommended target of two adequate stool specimens collected from at least 80% of AFP cases.

The EUR polio laboratory network consists of 41 laboratories (34 national laboratories; two subregional reference laboratories; and five regional reference laboratories).³ Of the 33 EUR network laboratories that underwent proficiency testing during 1996, a total of 25 rated a passing score (at least 80%) compared with five of the 15 laboratories tested in 1995.

From 1991 through 1995, the number of confirmed cases of polio reported in EUR ranged from 177 to 221; 193 cases were reported in 1996. Of the 50 EUR member states that reported 1996 data to WHO, 42 reported zero cases, compared with 38 countries in 1994 before Operation MECACAR. Of the nine countries with endemic or recently endemic disease that participated in Operation MECACAR during 1995-1997, two (Turkey and Turkmenistan) reported 21 cases in 1996. During 1991-1994, these nine countries had reported 78-221 polio cases each year. Of the 50 EUR member states that have reported 1997 data to WHO, only Tajikistan has reported one confirmed polio case. In 1996, most reported polio cases in EUR occurred during an outbreak that followed an importation of wild poliovirus type 1 into the Balkan peninsula. As part of that outbreak, 138 cases were reported from Albania⁴; additional cases occurred in young, undervaccinated population subgroups: among Roma (gypsies) in Greece (five cases) and among ethnic Albanians in the Kosova and Metohija district of the Federal Republic of Yugoslavia (24 cases). The outbreak in Albania primarily affected persons aged 10-34 years because of historical problems with the transport, storage, and administration of vaccines. The outbreak ended following mass vaccination of the entire population through age 50 years with two doses of OPV, reaching >85% of the target group. Similarly, in the Federal Republic of Yugoslavia the outbreak was terminated by previously planned sub-NIDs. Wild poliovirus type 1 also was isolated in Turkmenistan in July 1996. The remaining cases reported in 1996 (in the Republic of Moldova, Russian Federation, Turkey, and Ukraine) and 1997 (in Tajikistan) were clinically confirmed. Wild poliovirus types 1 and 3 were last isolated in Turkey in 1994 and 1995, respectively.

Based on epidemiologic investigations and the genomic characterization of wild poliovirus isolates, approximately 52% of the 1335 polio cases reported in EUR member states during January 1991-September 1997 were associated with indigenous transmission of wild poliovirus of origin from outside the involved country, and sometimes apparently from outside the EUR, primarily affecting susceptible populations or subgroups. During 1991-1995, most outbreaks were associated with wild poliovirus originating from the Indian subcontinent.^5- 6

Communicable Disease and Immunization Unit, European Regional Office, Copenhagen, Denmark. Global Program for Vaccines and Immunization, World Health Organization, Geneva, Switzerland. Respiratory and Enteric Viruses Br, Div of Viral and Rickettsial Diseases, National Center for Infectious Diseases; Polio Eradication Activity, National Immunization Program, CDC

Improvements in routine vaccination coverage and in surveillance in the EUR member states and the successes of Operation MECACAR have resulted in substantial progress toward regional elimination of wild poliovirus transmission. In addition to most of western and central Europe, which have not reported polio in the 1990s, polio transmission has been interrupted in virtually all of those countries in which polio was endemic. However, the quality of surveillance in many areas of the region must continue to improve to ensure that endemic transmission has been interrupted and that any transmission secondary to imported poliovirus is promptly detected.

Tajikistan, Turkmenistan, and Uzbekistan remain at risk for polio because of recent cases and suspected ongoing poliovirus transmission in Afghanistan; however, transmission might not be detected because of weak surveillance and/or laboratory deficiencies. In addition, some areas of Turkey—particularly those adjacent to Iran and Iraq—remain at high risk for wild poliovirus transmission.⁷

Supplemental vaccination activities (i.e., NIDs, sub-NIDs, and "mopping-up" [intensive house-to-house supplemental vaccination in high-risk areas]) will continue to be organized through 2000 under Operation MECACAR Plus to interrupt any remaining chains of poliovirus transmission. Mopping-up activities will be conducted in nearly all MECACAR countries during October-November 1997, with particular emphasis on the high-risk areas that border countries of the Eastern Mediterranean Region with endemic disease.

Since the late 1980s, large polio outbreaks have occurred nearly every year in EUR among undervaccinated religious or ethnic population subgroups or in countries where vaccination coverage decreased for economic reasons.^4- 5,8 As progress has been made in the interruption of endemic transmission, the relative importance of indigenous transmission of virus introduced from outside the region has increased. Therefore, specific efforts are needed to identify and improve the vaccination status of hard-to-reach population subgroups in member states (e.g., ethnic minorities, migrants, and displaced persons).

EUR priorities for the eradication of polio by 2000 include (1) further strengthening AFP surveillance systems throughout the region (including accreditation of polio network laboratories by mid-1998); (2) ensuring that high-quality NIDs or sub-NIDs are conducted through Operation MECACAR Plus in selected countries with persistent high risk for wild poliovirus circulation resulting from low vaccination coverage, weak surveillance, and/or administrative problems; (3) implementing coordinated intensive supplemental vaccination activities among key border area populations; (4) maintaining and strengthening the political commitment of governments for polio eradication and certification; (5) consolidating the support of donor governments and partner agencies to ensure sufficient financial and human resources are available; and (6) progressing in the formal process of certification. External technical and financial support provided to achieve progress in the polio eradication initiative in EUR has been provided by an international coalition consisting of WHO; United Nations Children's Fund (UNICEF); and other partner agencies including Rotary International, US Agency for International Development, CDC, and the governments of Canada, Denmark, France, Germany, Italy, Japan, Luxembourg, the Netherlands, Norway, Switzerland, and the United Kingdom and the European Commission Humanitarian Office.

*Mass campaigns over a short period (days to weeks) in which two doses of oral poliovirus vaccine are adminstered to all children in the target age group (usually aged 0-4 years) regardless of previous vaccination history, with an interval of 4-6 weeks between doses.

†Two stool specimens collected at an interval of at least 24 hours within 14 days of onset of paralysis.

MMWR. 1997;46:1130-1133

2 figures omitted

MOTOR-VEHICLE-related injuries are the leading cause of death for persons aged 1-24 years in the United States.¹ Although the relation between alcohol use and motor-vehicle-related deaths involving teenagers is well established,² understanding of the role of alcohol in such deaths among younger children is limited. To characterize the involvement of alcohol in motor-vehicle-related deaths of U.S. children aged <15 years during 1985-1996, CDC analyzed data from the Fatality Analysis Reporting System (FARS) of the National Highway Traffic Safety Administration (NHTSA). This report summarizes the results of that analysis, which indicate that approximately one fourth of all traffic deaths among children aged <15 years involved alcohol and that in nearly two thirds of passenger deaths involving a legally drunk driver, the child was in the car driven by the legally drunk driver.

FARS is a census of police-reported traffic crashes on public roadways that result in the death of at least one occupant or nonmotorist within 30 days of the crash. NHTSA considers a fatal motor-vehicle crash to be alcohol related if either a driver or non-occupant (e.g., pedestrian) had a blood alcohol concentration (BAC) ≥0.01 g/dL. Because BACs are not available for all persons involved in fatal crashes, NHTSA estimates the number of alcohol-related traffic fatalities based on a discriminant analysis of information from all cases for which driver or nonoccupant BAC data are available.³ Age adjustment of rates was performed by the direct method using the 1970 U.S. population.

During 1985-1996, of the 35,547 children aged <15 years who died in motor-vehicle crashes, 8482 (24%) were killed in alcohol-related motor-vehicle crashes. From 1985 to 1996, the proportion of all motor-vehicle-related deaths that involved alcohol decreased from 25% (773 of 3126 deaths) to 21% (568 of 2761). The death rate per 100,000 population attributable to alcohol-related crashes declined among children aged 0-4, 5-9, and 10-14 years. Among all children aged <15 years, the average annual death rate from alcohol-involved crashes was 1.3 times greater for males than for females (1.47 compared with 1.11).

During 1985-1996, a total of 5771 children died while traveling as occupants in a motor vehicle involved in an alcohol-related crash, composing 68% of all alcohol-related traffic fatalities among persons aged <15 years; an additional 1854 (22%) children who died were pedestrians, and 719 (8%) were bicyclists (for 137 [2%] fatalities, the status was unknown). From 1985 to 1996, the age-adjusted death rate for children who were motor-vehicle occupants in alcohol-involved crashes declined 26% (from 0.95 to 0.70); for those who were pedestrians, the rate declined 51% (from 0.39 to 0.19). For bicyclists aged 5-14 years, the rate of involvement in alcohol-related motor-vehicle crashes declined 62% (from 0.24 to 0.09).

From 1985 through 1996, a total of 3830 children aged <15 years were killed as passengers in a motor-vehicle crash involving a driver whose BAC was ≥0.10 g/dL. Of these, 2280 (60%) died while riding in the same vehicle with the drunk driver. Only 16% (336 of 2094) of these children were restrained at the time of the crash (information on restraint use was unknown for 186 children). For each age group, the percentage of children restrained varied inversely with their driver's BAC. Restraint use was lowest (11%) for children aged 10-14 years whose drivers had BACs ≥0.10 g/dL.

Div of Unintentional Injury Prevention, National Center for Injury Prevention and Control, CDC.

The findings in this report indicate that approximately one fourth of all motor-vehicle-related deaths among children aged <15 years involved alcohol and that in nearly two thirds of passenger deaths involving a legally drunk driver, the child was in the car driven by the legally drunk driver. The decline in the death rate for alcohol-involved crashes among children aged <15 years is consistent with a recent decline in the proportion of alcohol-involved deaths among drivers of all age groups.⁴ This decline coincides with passage of stricter laws about drinking and driving. In 33 states, driving with a BAC of ≥0.10 g/dL is illegal, and in 15 states the limit has been lowered to 0.08 g/dL (six states with a legal limit of 0.08 g/dL have adopted this lower limit since 1993).⁵

The proportion of children killed in crashes while in the same car as a driver with a BAC ≥0.10 g/dL is consistent with findings at a state level: during a 4-year period in North Carolina, of 51 child passengers who died in alcohol-related crashes, 36 (70%) were killed as passengers in vehicles in which their driver had been drinking and driving.⁶ The legislatures of 21 states have enacted child-endangerment laws that create a separate violation for persons who drive while legally intoxicated with a child in the vehicle⁵ ; however, the effectiveness of these laws has not been evaluated.

Despite recent declines in rates for alcohol-related traffic deaths, U.S. drivers continue to drink and drive at a high rate. During 1993, approximately 123 million episodes of self-reported alcohol-impaired driving occurred in the United States.⁷ Further reduction in alcohol-involved motor-vehicle-related fatalities among children will require a variety of interventions designed to change drinking and driving behaviors of adults, including altering drivers' perceptions of risk to themselves and to others riding with them, increasing efforts to screen for alcoholism among persons convicted of driving while intoxicated, and changing public policy to deter adult drinking and driving, especially when adults are transporting young children. The proportion of children in this analysis who died while riding unrestrained in the same vehicle as the drunk driver underscores the need for continuing efforts to increase safety-belt and child safety-seat usage among all motor-vehicle occupants. Drivers with a BAC ≥0.10 g/dL are less likely than drivers with lower BACs to wear safety belts,⁸ and this analysis indicates that their young passengers are at increased risk for riding unrestrained. Rigorous enforcement of primary safety-belt and child safety-seat laws by police, in addition to reducing drinking and driving, can protect children and other passengers from the hazards of alcohol-impaired driving.

MMWR. 1997;46:1028

THE FIRST Annual Conference on Vaccine Research: Basic Science—Product Development—Clinical and Field Studies will be held May 30-June 1, 1998, in Washington, D.C. Cosponsors are CDC, the National Foundation for Infectious Diseases (NFID); the National Institute of Allergy and Infectious Disease, National Institutes of Health; and the International Society for Vaccines. This meeting will focus on current scientific data and issues in the diverse disciplines involved in the research and development of vaccines and associated technologies for disease control through vaccination.

Additional information about program announcements, registration, reservations, and abstract submission is available from Kip Kantelo, NFID, 4733 Bethesda Avenue, Suite 750, Bethesda, MD 20814-5228; telephone (301) 656-0003; fax (301) 907-0878; e-mail: kkantelo@aol.com.; or the World-Wide Web site, http://www.medscape.com/NFID/conferences/vaccine98/.