Australian bat lyssavirus: implications for public health.

Australian bat lyssavirus (ABLV) infection in humans is rare but fatal, with no proven effective therapy. ABLV infection can be prevented by administration of a post-exposure prophylaxis regimen of human rabies immunoglobulin and rabies vaccine. All Australian bats (flying foxes and microbats) should be considered to be carrying ABLV unless proven otherwise. Any bat-related injury (bite, scratch or mucosal exposure to bat saliva or neural tissue) should be notified immediately to the relevant public health unit - no matter how small the injury or how long ago it occurred. Human-to-human transmission of ABLV has not been reported but is theoretically possible. Standard infection control precautions should be employed when managing patients with suspected or confirmed ABLV infection.

Acellular pertussis vaccine effectiveness for children during the 2009-2010 pertussis epidemic in Queensland.

UNLABELLED: OBJECTIVES To assess the effectiveness of three, four and five doses of acellular pertussis vaccine against pertussis notification for children aged 1 - < 4 years and 5 - < 12 years, and the effectiveness of three doses of acellular pertussis vaccine against pertussis hospitalisation for children aged 1 - < 4 years. DESIGN, SETTING AND PARTICIPANTS: A population-based retrospective study of children aged 1 - < 12 years residing in Queensland, Australia, during 2009 and 2010. Routinely collected notification, hospitalisation, testing and vaccination data were used to describe notification rates and testing patterns and to assess vaccine effectiveness (VE) by the screening method. MAIN OUTCOME MEASURES: VE against pertussis notification for children aged 1 - < 4 years and 5 - < 12 years, by birth year, and VE against pertussis hospitalisation for children aged 1 - < 4 years. RESULTS: 1961 notifications and 29 hospitalisations were included in the VE calculations. VE point estimates against pertussis notification and hospitalisation in children aged 1 - < 4 years were similar in 2009 and 2010, and ranged between 83.5% and 89.4%. VE point estimates against notification among children aged 5 - < 12 years were between 71.2% and 87.7% in 2009, and between 34.7% and 70.3% in 2010. The numbers of pertussis tests performed for children, particularly polymerase chain reaction (PCR) tests, increased between 2009 and 2010. CONCLUSIONS: Acellular pertussis vaccine provided good protection within the first years of priming, but this waned as age increased. Changes in pertussis testing behaviour, because of increases in PCR use and awareness, may have contributed to increased pertussis notification rates and lower estimates of VE against notification owing to identification of milder disease.

Preventing Australian bat lyssavirus: community knowledge and risk perception of bats in South East Queensland.

OBJECTIVES: Ongoing potential exposure of members of the public to Australian bat lyssavirus (ABLV) in South East Queensland, Australia, prompted investigation of community knowledge, risk perception, and intention to handle bats to inform future prevention efforts. METHODS: After pilot testing, a computer-assisted telephone survey of a representative sample of 700 adults without previous potential exposure to ABLV was undertaken in the defined geographic region. RESULTS: Twenty-four percent of eligible contacted individuals participated. Basic knowledge of bats and ABLV was generally high, with 65% of participants answering nine or more of 12 knowledge questions correctly. The perceived risk that bats pose to human health was also high, with 93% indicating some degree of risk. Although 88% of participants indicated they would handle bats in one or more of the scripted situations, overall intention to handle bats was low, with 59% indicating they would handle a bat in four or less of the 12 scenarios. Younger males with lower risk perception of bats most frequently indicated intention to handle bats in varying situations. Knowledge score was not associated with intention to handle bats on multivariate modeling. CONCLUSIONS: Future public health prevention efforts, both in Australia and overseas, should focus further on conveying the risk to humans and to bats when nontrained, nonvaccinated people attempt to handle bats rather than attempting to purely convey knowledge about bats and ABLV or rabies. Suitable alternative measures to handling should be included. Younger adult males are a particular target group for prevention efforts.

Potential exposure to Australian bat lyssavirus in south east Queensland: what has changed in 12 years?

Public health measures have been targeting potential exposure to Australian bat lyssavirus (ABLV) since the first recognised human cases, more than a decade ago. The effect of these measures on the epidemiology of notifications of potential exposure has not been investigated since 2003. Trends in notifications of potential exposure to ABLV reported to the Brisbane Southside Public Health Unit between November 1996 and October 2008 were examined. During the study period notification rates declined among all population groups and potential exposures were notified more promptly. The proportion of female notifications and the proportion of notifications from volunteer bat carers and their families and professional groups decreased over time. These changes over 12 years may indicate success of public health measures, under-reporting of potential exposure or both. Intentional handling of bats by untrained members of the public continues to be an important source of potential exposure to ABLV and requires a sustained public health response.

The impact of pre-departure screening and treatment on notifications of malaria in refugees in south-east Queensland.

This study aimed to investigate changes in the notification rate of malaria in refugees over a period of national policy change on pre-departure screening. Notifying clinicians were interviewed to complete a standardised enhanced surveillance form. A decline in refugee malaria notifications occurred after implementation of a national policy to offer pre-departure malaria screening and treatment as necessary to refugees. Surveillance data support the benefit of offering pre-departure screening and treatment as necessary to refugees.

An outbreak of shiga toxin-producing Escherichia coli infection associated with a school camp.

In November 2008, a case of Shiga toxin-producing Escherichia coli (STEC) infection was reported to the Brisbane Southside Public Health Unit. The case had participated in a school camp. Subsequent investigations confirmed 5 other asymptomatic cases among camp attendees or visitors. Examination of the camp water supply identified that most water sources had high levels of E. coli and did not meet the Australian Drinking Water Guidelines with STEC isolated from 2 water sources. This outbreak highlights the emerging issue of asymptomatic carriage of STEC and the importance of thorough maintenance and attention to drinking water supplies in the rural and school camp setting.

Outbreaks of Salmonella Typhimurium phage type 197 of multiple genotypes linked to an egg producer.

This paper describes outbreaks of Salmonella Typhimurium phage type 197 (STm197) linked to eggs from the farm of a single egg producer. Epidemiological and microbiological investigations (genotyping by multiple locus variable number tandem repeats analysis [MLVA]) identified outbreaks of STm197 with the same or closely-related MLVA profiles in a series of restaurants across Brisbane over 2 months. Environmental health investigations revealed that these restaurants were supplied with eggs from the same egg producer and that cross-contamination may have contributed to the outbreak. Environmental swabs taken from restaurant kitchens and the farm of the egg producer identified a number of salmonellas including STm197, many with MLVA profiles matching or closely related to the human strains from outbreak cases. A case-to-case comparison study showed a significant association between illness with 1 MLVA type and attending a restaurant during the 5 days before onset of illness (odds ratio [OR] 8.1, 95% confidence interval [CI] 1.8, 35.4). MLVA has become a valuable tool for S. Typhimurium surveillance and outbreak investigation. This outbreak further justifies the Commonwealth Government's decision to develop a draft national primary production and processing standard for eggs and egg products to address food safety risks posed by cracked and dirty eggs.

Observations on managing an outbreak of influenza A infection in an aged care facility.

Influenza outbreaks in aged care facilities (ACFs) can be associated with high morbidity and mortality. National guidance includes the use of antiviral medication for residents and staff and other measures to prevent serious health outcomes. An outbreak of influenza in an ACF was reported to the Brisbane Southside Population Health Unit (BSPHU) on 10 August 2007. The BSPHU assisted the ACF and local general practitioners in the provision of oseltamivir to staff and residents on 11 August 2007. The onset of illness in the last case was 13 August 2007. Antiviral prophylaxis was ceased and the outbreak declared over on 22 August 2007. This paper describes some of the practical issues encountered in the public health response in this setting. Vaccination of ACF residents and staff remains the key preventive strategy for the future.

Two years of enhanced surveillance of sexually-transmitted chlamydia in South East Queensland.

The National Sexually Transmissible Infections Strategy 2005-2008, released in 2005, lists exploring and addressing barriers to enhanced data collection for chlamydia surveillance among the actions required for chlamydia control and prevention. This study describes a method of enhanced surveillance of sexually transmitted chlamydia notifications undertaken in South East Queensland, and the epidemiology and management of chlamydia over the study period. The service providers of a random sample of chlamydia notifications meeting preset inclusion criteria were faxed an information package and questionnaire. Telephone follow-up was initiated for non-responders. The first year of data were compared to the second year of data. The overall response rate was 93.2 per cent. Males were more likely than females to be tested because of symptoms in the first year of the study, but not the second. Females were 5.2 times (95% CI 2.43, 10.91) more likely to be screened on the suggestion of the service provider than males. The positivity rate among those tested for sexually transmitted chlamydia increased across the study period. An information package and questionnaire faxed to notifying clinicians is a simple and effective means of conducting enhanced surveillance of sexually transmitted chlamydia. An increase in the screening of males may be contributing to the increasing rate of notifications. An increasing positivity rate among all those tested for chlamydia may be due to more prevalent disease, or more focused testing of high risk groups.

Trends in potential exposure to Australian bat lyssavirus in South East Queensland, 1996 to 2003.

This study examined trends in notifications of potential exposure to Australian bat lyssavirus reported to the Brisbane Southside Public Health Unit, Australia between 1 November 1996 and 31 January 2003. Notification rates declined among all population groups and potential exposures were notified more promptly. Concern exists regarding possible under-reporting of potential exposure to Australian bat lyssavirus especially among volunteer bat carers.

A statewide outbreak of Salmonella bovismorbificans phage type 32 infection in Queensland.

Between 30 May and 1 June 2001, 10 cases of Salmonella Bovismorbificans infection were reported to Public Health Services, Queensland Health. Investigations included enhanced surveillance, case interviews, a matched case control study, environmental audit and microbiological testing of faecal isolates (phage typing) and implicated food products. Forty-one cases of S. Bovismorbificans infection were detected, 36 cases were phage type 32. A matched case control study identified that illness was associated with consumption of food from 15 outlets of a fast food chain, Company A (matched odds ratio [MOR] 17.5, 95% CI 2.0-657.3, p = 0.004) and consumption of a particular product, Product X (MOR undefined, p < 0.001) in the week before onset of illness. Manufacturers of Product X ingredients were audited. Deficiencies were identified in equipment cleansing at the salad mixture processing plant (Manufacturer M). A swab of food residue behind the cutting wheel rim of the lettuce shredder was positive for S. Bovismorbificans phage type 32. This appears to be the first reported Australian outbreak of salmonellosis associated with a lettuce product. The investigations suggest that inadequate maintenance of cutting equipment to prepare lettuce ingredients for Product X by Manufacturer M was a key factor in this statewide outbreak. The statewide nature of this outbreak demonstrates the role of timely serovar identification of Salmonella isolates by a reference laboratory as an aid to outbreak identification, and the importance of adherence to appropriate food safety procedures in the manufacture and preparation of mass produced food items for the public.