Epidemiology of equine upper respiratory tract disease on standardbred racetracks.

The outbreaks of upper respiratory tract infections in horses at Standardbred racetracks were investigated over a three year period. The most serious epidemics of respiratory disease occurred in the winter and spring seasons. Both influenza viruses and equine herpesvirus 1 were shown to be present in the horse population. The herpesvirus was associated with respiratory disease particularly in the winter but the equine influenza viruses apparently were responsible for the major epidemics of respiratory disease at these tracks. Younger horses, two or three years of age, were particularly susceptible to upper respiratory disease and showed the greatest rate of seroconversion to influenza viruses. Major outbreaks of respiratory disease occurred when the proportion of young horses which had not previously been exposed to epidemics of respiratory disease reached 30 to 40% of the population at the track. Most horses over four years of age appeared to develop resistance to the infections.     

Somatosensory potentials, CSF creatine kinase BB activity, and awakening after cardiac arrest

OBJECTIVE: To examine the utility of somatosensory evoked potential (SEP) peaks and CSF creatine kinase BB isoenzyme activity (CKBB) in predicting nonawakening from coma due to cardiac arrest. BACKGROUND: Accurate predictors of neurologic outcome in patients comatose after cardiac arrest are needed to improve medical decision making. METHODS: A total of 72 comatose patients had bilateral median SEPs, and of these, 52 had CSF and CKBB. Awakening was defined as following commands or having comprehensible speech. Both short (N1) and long (N3) latency SEP peaks were analyzed. Nonparametric analyses were used. RESULTS: For patients who had both tests, CKBB > or = 205 U/L predicted nonawakening with a sensitivity of 49% and a specificity of 100%. Bilateral absence of the N1 peak predicted nonawakening with a sensitivity of 53% and a specificity of 100%. Using CKBB > or = 205 U/L, bilaterally absent SEP N1 peaks, or both predicted nonawakening with a sensitivity of 69% and a specificity of 100%. Using CKBB > or = 205 U/L, bilaterally absent N1 peaks, bilateral N3 > or = 176 msec or absent, or some combination predicted nonawakening with a sensitivity of 78% and a specificity of 100%. CONCLUSION: The combination of an absent N1 peak and elevated CKBB performs better than either alone in predicting nonawakening after cardiac arrest. Prolonged or absent N3 latency may increase sensitivity. These results should be interpreted with caution given the small number of patients and the possibility of a self-fulfilling prophecy.     

Effect of depression on neuropsychological functioning in head injury: measurable but minimal

The goals of the study were to determine how neuropsychological functioning is related to depressive status in persons with head injury, and to quantify this relationship from a clinically relevant standpoint. Participants were 175 adults involved in litigation, referred for evaluation of suspected head injury. Depression status was measured using the Depression Content (Dep) scale of the MMPI-2. Depression status was related to measures of visual attention and psychomotor skills, but not to other neuropsychological domains such as verbal ability, visual-spatial reasoning, or encoding/organization. However, differences between low Dep and high Dep groups were minimal from a clinical standpoint. Depression appeared to contribute to an increased risk of impaired neuropsychological performance across domains, but only in persons not severely compromised by neuropsychological deficits. Overall, the results indicated a small effect of depression on neuropsychological functioning that is likely only detectable in persons whose neuropsychological compromise is relatively minimal.     

Direct and indirect acquisition of syringes from syringe exchange programmes in Baltimore, Maryland, USA

Syringe exchange programmes (SEPs) are a fundamental source of sterile syringes and other health services for injection drug users (IDUs). However, various obstacles prevent many individuals from obtaining syringes from this source. As a result, some IDUs acquire syringes from “secondary exchangers”. The current study assessed the acquisition of syringes from the Baltimore City Needle Exchange Program (BNEP) as well as factors associated with obtaining syringes from the BNEP. Participants were asked to identify the colour of the cap of the most recently obtained syringe (red or grey cap suggested BNEP origins). In addition, support and risk network variables were examined. Although 38% reported using a syringe with a grey or red cap, only 7% reported that the BNEP was their primary source of syringes. Multivariate analyses showed that reporting the most recent syringe cap as red or grey was associated with obtaining syringes from the BNEP, obtaining syringes from a spouse, obtaining syringes from friends/neighbours, and number of drug users in their network. Based on these findings, encouraging secondary exchange is an effective method of providing injectors with syringes.     

Seroreactivity to human papillomavirus (HPV) types 16, 18, or 31 and risk of subsequent HPV infection: results from a population-based study in Costa Rica.

Whether antibodies to human papillomavirus (HPV) capsids, elicited by natural infection, are protective is unknown. This question was addressed in a population-based cohort of 7046 women in Costa Rica by examining the association between baseline seroreactivity to HPV-16, HPV-18, or HPV-31 virus-like particles and the risk of subsequent HPV infection at a follow-up visit 5-7 years after enrollment. Seropositivity to HPV-16, HPV-18, or HPV-31 was not associated with a statistically significant decreased risk of infection with the homologous HPV type [relative risk (RR) and [95% confidence interval (CI)], 0.74 (0.45-1.2), 1.5 (0.83-2.7), and 0.94 (0.48-1.8), respectively]. Seropositivity to HPV-16 or HPV-31 was not associated with a decreased risk of infection with HPV-16 or its genetically related types [RR (95% CI), 0.82 (0.61-1.1) and 0.93 (0.68-1.2), respectively]. Seropositivity to HPV-18 was not associated with a decreased risk of infection with HPV-18 or its genetically related types (RR 1.3; 95% CI 1.0-1.8). Thus, we did not observe immunity, although a protective effect from natural infection cannot be excluded because of the limits of available assays and study designs.