Effects of temperature on viral load, inclusion body formation, and host response in Pacific Herring with viral erythrocytic necrosis (VEN).

OBJECTIVE: The primary objective of this study was to determine the effects of temperature on viral erythrocytic necrosis (VEN) progression under controlled conditions. Secondarily, this study was intended to evaluate the combined effects of temperature and VEN on the Pacific Herring Clupea palasii transcriptome. METHODS: The effects of temperature on VEN progression were assessed by waterborne exposure of laboratory-reared, specific-pathogen-free Pacific Herring to tissues homogenates containing erythrocytic necrosis virus (ENV) at 6.9, 9.0, or 13.5°C. RESULT: Exposure of Pacific Herring to ENV resulted in the establishment of infections characterized by high infection prevalence (89%; 40/45) and mean viral loads (5.5 log10 [gene copies/µg genomic DNA]) in kidney tissues at 44 days postexposure. Mean viral loads were significantly higher in fish from the ambient (mean = 9.0°C) and warm (mean = 13.5°C) treatments (6.1-6.2 log10 [gene copies/total genomic DNA]) than in fish from the cool (mean = 6.9°C) treatment (4.3 log10 [gene copies/µg genomic DNA]). Similarly, the peak proportion of diseased fish was directly related to temperature, with cytoplasmic inclusion bodies detected in 21% of fish from the cool treatment, 52% of fish from the ambient treatment, and 60% of fish from the warm treatment. The mean VEN load in each fish (enumerated as the percentage of erythrocytes with cytoplasmic inclusions) at 44 days postexposure increased with temperature from 15% in the cool treatment to 36% in the ambient treatment and 32% in the warm treatment. Transcriptional analysis indicated that the number of differentially expressed genes among ENV-exposed Pacific Herring increased with temperature, time postexposure, and viral load. Correlation network analysis of transcriptomic data showed robust activation of interferon and viral immune responses in the hepatic tissue of infected individuals independent of other experimental variables. CONCLUSION: Results from this controlled laboratory study, combined with previous observations of natural epizootics in wild populations, support the conclusion that temperature is an important disease cofactor for VEN in Pacific Herring.

An evaluation of a plastic strip thermometer.

The Clinitemp Fever Detector (a registered trademark for the Clinitemp Co, Indianapolis) is a plastic strip thermometer designed to be placed on the forehead and to detect body temperature by changing color. In a sample of 613 patients, we evaluated the ability of the Clinitemp to detect fevers detected by traditional mercury/glass thermometers. When a Clinitemp reading of 37.8 degrees C (100 degrees F) was used to demark fever, the Clinitemp detected 34% of the clinically significant fevers detected by the mercury/glass thermometers. The sensitivity of the Clinitemp rose to .81 when a Clinitemp reading of 37.2 degrees C (99 degrees F) was used to demark fever. The accuracy of the Clinitemp was affected by variations in ambient air temperature. A reassessment of previously published evaluations of plastic strip thermometers suggest that our results are consistent with other experimental findings. We conclude that the Clinitemp is unacceptable as a substitute for the mercury/glass thermometer.

A multidisciplinary clerkship in emergency medicine.

An obligatory, multidisciplinary, fourth-year emergency medicine clerkship is described and the particular problems of multidisciplinary courses discussed. The course is designed to produce medical students who adequately demonstrate: knowledge of emergency care and facility in specified skills, familiarity with the appropriate use of an emergency room, and conversance with treatment of nonemergency cases. Students are required to complete successfully an advanced cardiac life support providers course, serve on ambulance duty, rotate through a community hospital emergency room, and participate in the more traditional clinical experiences. The course offers the fourth-year student an opportunity to synthesize prior knowledge within the context of a multidisciplinary patient care experience.

The use of cable television as a tool in health education of the elderly: screening.

A cable television channel was used to inform residents in a housing project for the elderly about a series of preventive health services. Screening and referral services for common health problems were offered to this group. The televised communications included a series of brief, informal advertising-style and direct teaching-style messages developed for each of five screening areas. An evaluation found that the televised messages had both direct and indirect effects on participation in the screening programs; overall attendance was about 8% of the estimated potential attendance. Knowledge and health attitude effects of the messages were also assessed.