Tracking viral evolution during a disease outbreak: the rapid and complete selective sweep of a circovirus in the endangered Echo parakeet.

Circoviruses are among the smallest and simplest of all viruses, but they are relatively poorly characterized. Here, we intensively sampled two sympatric parrot populations from Mauritius over a period of 11 years and screened for the circovirus Beak and feather disease virus (BFDV). During the sampling period, a severe outbreak of psittacine beak and feather disease, which is caused by BFDV, occurred in Echo parakeets. Consequently, this data set presents an ideal system for studying the evolution of a pathogen in a natural population and to understand the adaptive changes that cause outbreaks. Unexpectedly, we discovered that the outbreak was most likely caused by changes in functionally important regions of the normally conserved replication-associated protein gene and not the immunogenic capsid. Moreover, these mutations were completely fixed in the Echo parakeet host population very shortly after the outbreak. Several capsid alleles were linked to the replication-associated protein outbreak allele, suggesting that whereas the key changes occurred in the latter, the scope of the outbreak and the selective sweep may have been influenced by positive selection in the capsid. We found evidence for viral transmission between the two host populations though evidence for the invasive species as the source of the outbreak was equivocal. Finally, the high evolutionary rate that we estimated shows how rapidly new variation can arise in BFDV and is consistent with recent results from other small single-stranded DNA viruses.

A quantitative survey of intern's knowledge of communication skills: an Iranian exploration.

BACKGROUND: It is a high priority that health care providers have effective communication skills. It has been well documented that the doctor-patient relationship is central to the delivery of high quality medical care, and it has been shown to affect patient satisfaction, to decrease the use of pain killers, to shorten hospital stays, to improve recovery from surgery and a variety of other biological, psychological and social outcomes. This study sought to quantify the current knowledge of interns in Iran about communication skills. METHODS: A cross-sectional study using a self-report questionnaire was conducted among interns. Data analysis was based on 223 questionnaires. The internal consistency of the items was 0.8979. RESULTS: Overall, knowledge levels were unsatisfactory. Results indicated that interns had a limited knowledge of communication skills, including identification of communication skills. In addition, there was a significant difference between the mean scores of interns on breaking bad news and sex education. The confidence of males about their communication skills was significantly higher than for females. Analysis of the total scores by age and sex showed that there was a statistically significant main effect for sex and the interaction with age was statistically significant. Free response comments of the interns are also discussed. CONCLUSIONS: It is argued that there is a real need for integrating a communication skills course, which is linked to the various different ethnic and religious backgrounds of interns, into Iranian medical curricula. Some recommendations are made and the limitations of the study are discussed.

Optimal vaccination policies for stochastic epidemics among a population of households.

This paper considers stochastic epidemics among a population partitioned into households, with mixing locally within households and globally throughout the population. The two levels of mixing have important implications for the threshold behaviour of the epidemic and consequently for the form and construction of optimal vaccination policies. Optimality is considered in terms of the cost of the vaccination program, the form of which is general enough to include costs of the vaccine itself, its administration, travel to and/or contact with the households. New explicit results are obtained by a constructive method which explain the form of optimal vaccination policies. Numerical studies are presented which exemplify the results discussed.