Human T-cell leukaemia virus type 1 and Adult T-cell leukaemia/lymphoma in Queensland, Australia: a retrospective cross-sectional study.

OBJECTIVES: Human T-cell leukaemia virus type 1 (HTLV-1), an STI, is reported to be highly prevalent in Indigenous communities in Central Australia. HTLV-1 is an incurable, chronic infection which can cause Adult T-cell leukaemia/lymphoma (ATL). ATL is associated with high morbidity and mortality, with limited treatment options. We studied the prevalence of HTLV-1 and ATL in the state of Queensland, Australia. METHODS: Serum samples stored at healthcare services in Brisbane, Townsville and Cairns and at haemodialysis units in Brisbane (2018-2019) were screened for HTLV-1/2 antibodies using the Abbott ARCHITECT chemiluminescent microparticle immunoassay (CMIA) for antibodies against gp46-I, gp46-II and GD21 (Abbott CMIA, ARCHITECT). Reactive samples were confirmed through Western blot. Pooled Australian National Cancer Registry surveillance data reporting on cases coded for ATL (2004-2015) were analysed. RESULTS: Two out of 2000 hospital and health services samples were confirmed HTLV-1-positive (0.1%, 95% CI 0.02% to 0.4%), both in older women, one Indigenous and one non-Indigenous. All 540 haemodialysis samples tested negative for HTLV. All samples were HTLV-2-negative. Ten out of 42 (24.8%) reported cases of ATL in Australia were from Queensland (crude incidence rate 0.025/100 000; 95% CI 0.011 to 0.045); most cases were seen in adult men of non-Indigenous origin. Nineteen deaths due to ATL were recorded in Australia. CONCLUSION: We confirm that HTLV-1 and ATL were detected in Queensland in Indigenous and non-Indigenous people. These results highlight the need for HTLV-1 prevalence studies in populations at risk of STIs to allow the implementation of focused public health sexual and mother-to-child transmission prevention strategies.

Seroprevalence of Severe Acute Respiratory Syndrome Coronavirus 2-Specific Antibodies in Australia After the First Epidemic Wave in 2020: A National Survey.

BACKGROUND: As of mid-2021, Australia's only nationwide coronavirus disease 2019 (COVID-19) epidemic occurred in the first 6 months of the pandemic. Subsequently, there has been limited transmission in most states and territories. Understanding community spread during the first wave was hampered by initial limitations on testing and surveillance. To characterize the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibody seroprevalence generated during this time, we undertook Australia's largest national SARS-CoV-2 serosurvey. METHODS: Between June 19 and August 6, 2020, residual specimens were sampled from people undergoing general pathology testing (all ages), women attending antenatal screening (20-39 years), and blood donors (20-69 years) based on the Australian population's age and geographic distributions. Specimens were tested by Wantai total SARS-CoV-2-antibody assay. Seroprevalence estimates adjusted for test performance were produced. The SARS-CoV-2 antibody-positive specimens were characterized with microneutralization assays. RESULTS: Of 11 317 specimens (5132 general pathology; 2972 antenatal; 3213 blood-donors), 71 were positive for SARS-CoV-2-specific antibodies. Seroprevalence estimates were 0.47% (95% credible interval [CrI], 0.04%-0.89%), 0.25% (CrI, 0.03%-0.54%), and 0.23% (CrI, 0.04%-0.54%), respectively. No seropositive specimens had neutralizing antibodies. CONCLUSIONS: Australia's seroprevalence was extremely low (<0.5%) after the only national COVID-19 wave thus far. These data and the subsequent limited community transmission highlight the population's naivety to SARS-CoV-2 and the urgency of increasing vaccine-derived protection.

Technique for measuring very small angle changes.

A method for making accurate and precise measurements of small angles is described using an interferometer and a test fixture with reference control surfaces. The test is relatively insensitive to test fixture alignment. Typical measurement uncertainties are better than 0.2 arcsec (1σ). This technique is applicable for verifying the angular stability of opto-mechanical systems that must undergo rigorous environmental testing.

Enhanced diagnosis of pandemic (H1N1) 2009 influenza infection using molecular and serological testing in intensive care unit patients with suspected influenza.

During the 2009 outbreak of pandemic (H1N1) 2009 influenza (pH1N1) in Australia, acute and convalescent serum specimens were collected from 33 patients with severe respiratory disease admitted to intensive care units. Using hemagglutination inhibition of pH1N1, 29 paired serum samples showed significant increases in specific antibody titers. Of these 29 patients, 18 had pH1N1 RNA detected by routine nucleic acid testing. These results indicate that up to one-third of pH1N1 cases may not have laboratory confirmation of infection unless serological testing is included for suspected cases.

Detection of HBsAg mutants in a population with a low prevalence of hepatitis B virus infection.

Two independent studies were conducted to evaluate performance of two HBsAg immunoassay products performed on the Abbott ARCHITECT and Bayer ADVIA Centaur immunoassay analyzers. One was a retrospective study of 484 stored samples and the second was a prospective study of 349 samples from random population. In the process of the evaluation, a number of discordant samples from HBsAg-positive patients were found which led to the discovery of a number of HBsAg mutants in the general Australian population. Following viral DNA sequencing, these were identified as HBsAg escape mutants. Whilst the existence of HBsAg mutants has been well documented in various regions of the world, this is surprising in an area of low endemicity and demonstrates the necessity of an HBsAg assay to detect mutants reliably in a diagnostic situation where HBsAg is used as the only marker to detect an HBV infection. These studies demonstrate the ability of the Abbott ARCHITECT and AxSYM HBsAg immunoassays to detect these HBsAg mutations which were not detected by the Bayer ADVIA Centaur.