Human coronavirus OC43 causes influenza-like illness in residents and staff of aged-care facilities in Melbourne, Australia.

Three outbreaks of respiratory illness associated with human coronavirus HCoV-OC43 infection occurred in geographically unrelated aged-care facilities in Melbourne, Australia during August and September 2002. On clinical and epidemiological grounds the outbreaks were first thought to be caused by influenza virus. HCoV-OC43 was detected by RT-PCR in 16 out of 27 (59%) specimens and was the only virus detected at the time of sampling. Common clinical manifestations were cough (74%), rhinorrhoea (59%) and sore throat (53%). Attack rates and symptoms were similar in residents and staff across the facilities. HCoV-OC43 was also detected in surveillance and diagnostic respiratory samples in the same months. These outbreaks establish this virus as a cause of morbidity in aged-care facilities and add to increasing evidence of the significance of coronavirus infections.

Changing epidemiology of genital herpes simplex virus infection in Melbourne, Australia, between 1980 and 2003.

OBJECTIVE: To investigate changes in the proportions of patients infected with genital herpes simplex virus (HSV) types 1 and 2 from 1980 to 2003 in Melbourne, Australia. METHODS: A total of 25 372 patients were studied retrospectively. The proportions of HSV-1 and HSV-2 detected in these individuals were analysed by age, sex, and genital site. RESULTS: In 1980 only 15.8% of HSV positive genital specimens were HSV-1 compared to 34.9% in 2003. In 2003 HSV-1 was detected in 77% of patients aged less than 20 years. Females were more likely to be infected with HSV-1, although the rate of increased detection was more pronounced in males. Except for females over the age of 40, the trend for the increase in HSV-1 was detected in all age groups. No specific genital site in either sex was associated with the increase. CONCLUSIONS: The proportion of genital HSV-1 has increased in Australian patients, although HSV-2 is still the most common cause of genital infection. Confirmation of HSV type is necessary for optimal patient management.

Detection of varicella zoster virus in genital specimens using a multiplex polymerase chain reaction.

OBJECTIVE: To compare the relative proportions of varicella zoster virus (VZV) and herpes simplex viruses in specimens obtained from the genital lesions of adults presenting with presumed genital herpes infection. METHODS: Swabs of genital lesions from 6210 patients attending general practices, infectious diseases clinics within hospitals, or sexual health centres for treatment of their genital lesions were tested using polymerase chain reaction (PCR) technology. The multiplexed PCR was capable of detecting herpes simplex virus types 1 and 2 (HSV-1, HSV-2), VZV, and cytomegalovirus in a single sample. RESULTS: A total of 2225 patients had viruses detected by PCR. HSV-1 was detected in 36%, HSV-2 in 61%, and VZV in 2.9% of PCR positive samples. Of the 65 patients with VZV genital infection, many were thought to have HSV infection before laboratory testing. CONCLUSIONS: The finding of VZV in nearly 3% of virus positive genital specimens demonstrates that this virus needs to be considered as a differential diagnosis for genital herpetic lesions. Advice provided to patients with VZV genital infection regarding the source of infection, likelihood of recurrence, and potential for transmission of the virus will be different from that given to patients with HSV infection.

Enhanced measles surveillance during an interepidemic period in Victoria.

OBJECTIVE: To describe results of the first two years of enhanced measles surveillance in Victoria. DESIGN: Case series identified through enhanced measles surveillance. PARTICIPANTS AND SETTING: All measles cases notified to the Disease Control Section, Department of Human Services, Victoria, in 1997 and 1998. MAIN OUTCOME MEASURES: Proportion of notified cases laboratory confirmed as measles, rubella, or human parvovirus infection; identification of clusters (two or more linked cases of measles); and utility of the National Health and Medical Research Council clinical case definition for suspected measles. RESULTS: Rates of laboratory testing of notified cases improved after introduction of a paediatric phlebotomy service in July 1997, from 21 of 90 notified patients (23%) in the preceding six months, to 258 of 317 notified patients (81%) between July 1997 and December 1998. Of the 317, only 19 (6%) were laboratory confirmed with measles, while a further 26 (8%) were laboratory confirmed with human parvovirus infection (18) or rubella (8). Three clusters of measles, involving 11 cases, were identified during 1998. Use of the NHMRC case definition did not greatly improve the positive predictive value for diagnosis of measles above that of notification alone (14% versus 8%). CONCLUSIONS: Circulation of measles virus in Victoria in 1997 and 1998 appeared minimal. In this interepidemic period most notified cases of measles were not measles; to identify true cases, surveillance during an interepidemic period must include laboratory testing of notified cases.

Measles outbreak in young adults in Victoria, 1999.

OBJECTIVES: To describe an outbreak of measles in Victoria. DESIGN: Case series with cases identified through enhanced passive surveillance and outbreak-related active surveillance. SETTING: State of Victoria, 1999. MAIN OUTCOME MEASURES: Number of cases; epidemiological links and patterns of transmission; patient demographic features and vaccination status; complications. RESULTS: 75 cases were identified (74 laboratory-confirmed; and one epidemiologically linked to a laboratory-confirmed case), with onset between 11 February and 2 May 1999. The first case was in a 21-year-old woman who had recently holidayed in Bali and worked at a large cinema complex in Melbourne. Sixteen cases occurred in people who had contact with the index case at the cinema on one evening. The outbreak spread to regional Victoria and South Australia. Median age of patients was 22 years; 64 (85%) were born between 1968 and 1981, with only one patient in the age group targeted by the primary school component of the 1998 Australian Measles Control Campaign; this child had not been vaccinated. More than a third of patients (28) were hospitalised (total, 97 inpatient days), and five were healthcare workers. CONCLUSIONS: This outbreak was caused by international importation of measles virus. It highlights the change in epidemiology of measles in Australia, from a disease of childhood to one predominantly affecting young adults. A strong two-dose childhood vaccination program, vigilant surveillance, and rapid response to outbreaks will continue to be the basis of measles control, but better protection for young adults should be considered.