Evaluation of pathways for release of Rift Valley fever virus into domestic ruminant livestock, ruminant wildlife, and human populations in the continental United States.

OBJECTIVE: To evaluate the feasibility for Rift Valley fever virus (RVFV) to enter the continental United States by various routes as well as to identify states in which domestic and wild ruminant and human populations would be most vulnerable to exposure to RVFV. STUDY DESIGN: Pathways analysis. SAMPLE POPULATION: Animals, commodities, and humans transported from RVFV-endemic countries to the continental United States between 2000 and 2005. PROCEDURES: Initially, agent, host, and environmental factors important in the epidemiologic aspects of RVFV were used to develop a list of potential pathways for release of RVFV into the continental United States. Next, the feasibility of each pathway was evaluated by use of data contained in governmental and public domain sources. Finally, entry points into the continental United States for each feasible pathway were used to identify the domestic and wild ruminant and human populations at risk for exposure to RVFV. RESULTS: Feasible pathways for entry of RVFV into the continental United States were importation of RVFV-infected animals, entry of RVFV-infected people, mechanical transport of RVFV-infected insect vectors, and smuggling of live virus. CONCLUSIONS AND CLINICAL RELEVANCE: Domestic ruminant livestock, ruminant wildlife, and people in 14 states (Alabama, California, Florida, Georgia, Maine, Maryland, Massachusetts, Minnesota, New Jersey, New York, Pennsylvania, South Carolina, Texas, and Virginia) appeared to be most vulnerable to exposure to RVFV. Pathways analysis can provide the requisite information needed to construct an effective targeted surveillance plan for RVFV to enable rapid detection and response by animal health and public health officials.

Helicobacter pylori infection among non-Native educators in Alaska.

OBJECTIVES: To determine seroprevalence of H. pylori infection in non-Native educators residing in urban or rural settings in Alaska, and to determine potential risk factors associated with infection in this population. STUDY DESIGN: A cross-sectional survey of non-Native educators residing in urban or rural settings in Alaska. METHODS: Participants completed a questionnaire detailing aspects of residential life; H. pylori antibody status was determined by a commercial assay. RESULTS: Of the 203 non-Native participants, 49 (24%) had antibody to H. pylori. Univariate analysis demonstrated that the mean age of seropositive participants was higher than of seronegatives (48 vs. 42 years, respectively, p = .001). In addition, participants who had experienced childhood crowding were more likely to test seropositive for H. pylori (p = .058). On multivariate analysis, only age > or = 40 was associated with infection. No difference in median hemoglobin or ferritin levels were noted among seropositive and seronegative participants. There was no increased risk of seropositivity among participants who had lived in an Alaska Native village or in a developing country for > or = 6 months. CONCLUSIONS: Overall, 24% of non-Native educators residing in rural Alaska tested positive by serology for H. pylori. Age > or = 40 years was associated with infection. Median hemoglobin or ferritin levels did not differ significantly among seropositive and seronegative participants.

Public health evaluation of cadmium concentrations in liver and kidney of moose (Alces alces) from four areas of Alaska.

Liver and/or kidney samples were collected from 139 hunter-killed moose from four areas of Alaska during 1986. The concentration of cadmium in organ tissue was determined by direct-current plasma atomic emission spectrometry. All results are reported as mug/g wet weight. Concentrations of cadmium in liver ranged from 0.06 microg/g to 9.0 microg/g; in the kidney cortex they ranged from 0.10 microg/g to 65.7 microg/g. Cadmium levels were significantly associated with location and age. The highest geometric mean liver (2.11 microg/g) and kidney cortex (20.2 microg/g) cadmium concentrations were detected in moose harvested near Galena, Alaska. Limited dietary information from Alaska and Canada indicates that the intake of moose liver or kidney does not exceed, in most individuals, the World Health Organization recommendations for weekly cadmium consumption of 400 microg to 500 microg. Additionally, human biomonitoring data from Canada and Alaska indicate exposure to cadmium is low except for individuals who smoke cigarettes. Given the nutritional and cultural value of subsistence foods, the Alaska Division of Public Health continues to support the consumption of moose liver and kidney as part of a well-balanced diet. Human biomonitoring studies are needed in Alaska to determine actual cadmium exposure in populations with a lifelong history of moose liver and kidney consumption.

Human biomonitoring to optimize fish consumption advice: reducing uncertainty when evaluating benefits and risks.

National fish consumption advisories that are based solely on assessment of risk of exposure to contaminants without consideration of consumption benefits result in overly restrictive advice that discourages eating fish even in areas where such advice is unwarranted. In fact, generic fish advisories may have adverse public health consequences because of decreased fish consumption and substitution of foods that are less healthy. Public health is on the threshold of a new era for determining actual exposures to environmental contaminants, owing to technological advances in analytical chemistry. It is now possible to target fish consumption advice to specific at-risk populations by evaluating individual contaminant exposures and health risk factors. Because of the current epidemic of nutritionally linked disease, such as obesity, diabetes, and cardiovascular disease, general recommendations for limiting fish consumption are ill conceived and potentially dangerous.

Association of regulatory issues with an echovirus 18 meningitis outbreak at a children's summer camp in Alaska.

We document an echovirus 18 meningitis outbreak occurring at a remote overnight children's camp in Alaska. The outbreak involved 26% of 113 camp residents, was associated with building overcrowding and occurred in a camp with a contaminated drinking water source. Lack of specific children's camp regulations and failure to implement and enforce existing regulations may have contributed to the outbreak.

Incremental effectiveness of 2 doses of measles-containing vaccine compared with 1 dose among high school students during an outbreak.

A measles outbreak occurred among a highly vaccinated population in Alaska during 1998, providing an opportunity to determine the incremental efficacy of >or=2 doses of measles-containing vaccine (MCV) compared with 1 dose. Of 33 confirmed case patients identified, 31 had been vaccinated with 1 dose of MCV, 1 had received 2 doses, and vaccination status was unknown in 1 case. Seventy percent of cases were school-associated; 58% of cases occurred in 2 high schools. Of 3679 students attending the 2 schools, 50.4% and 45.5% had received >or=2 doses of MCV before measles introduction at the schools. The relative risk of developing measles among persons vaccinated with >or=2 doses of MCV compared with 1 dose was 0.06 (95% confidence interval, 0.01-0.44; P<.001), yielding an estimated incremental vaccine efficacy of 94.1% (95% confidence interval, 55.9%-99.2%; P<.001). Rapid implementation of a mandatory second-dose MCV requirement probably limited the extent of this outbreak.