Isolation of Ross River virus from mosquitoes and from horses with signs of musculo-skeletal disease.

OBJECTIVE: To report clinical and clinicopathological findings in horses naturally infected with Ross River virus (RRV) and identify likely mosquito arbovirus vector species. PROCEDURES: Veterinarians submitted serum samples from 750 horses because they suspected Ross River virus (RRV) infection. The samples were tested for the presence of IgM and IgG antibody to RRV and for the presence of virus. Mosquitoes were trapped, differentiated to species level and tested for the presence of RRV by virus isolation. RESULTS: RRV was isolated from six species of mosquitoes (Ochlerotatus camptorhyncus, Culex globocoxitus, Cx. australicus, Cx. annulirostris, Cx. quinquefasciatus, Anopheles annulipes) and from 13 horses with clinical signs of musculo-skeletal disease. Antibody to RRV was detected in 420 of the 750 serum samples; 307 contained IgG only; 76 contained both IgM and IgG and 37 contained only IgM antibody to RRV. Virus was isolated from horses with IgM antibody only. CONCLUSIONS: RRV can be isolated from infected horses during the short time period when there is an overlap of clinical signs, positive IgM serology and viraemia. Early spring infections of horses may occur if RRV infected mosquito vectors are present. RRV has not been shown to cause clinical disease in horses. This is the first report of isolation of RRV from Oc. camptorhyncus in the Murray region and indicates a potential for infection of humans and animals in autumn as well as in spring.

Competence of medical students in history taking during the clinical course.

Twelve students were selected from each of the three clinical undergraduate years, two from each year interviewing one of six simulated patients. The interviews were video recorded and scored by two clinicians on a rating system involving sixteen criteria. In addition to the expected differences between individual students, when the scores were placed in rank order a pattern of differences between years of study emerged. Students of the third clinical year performed better than those of first year and both were better than those of the intermediate second year. Junior students displayed more personal concern for the patients, while senior students tended to conduct a more controlled and structure interview.

Patterns of acquisition of interview skills by medical students.

The interviewing skills of six medical students were recorded on videotape annually during their years of clinical training. Many faults were identified, and an overall style of interview tended to persist through to the pre-registration year. However, individual students changed in different ways that could not be predicted from the results of the first interview.