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The composition of Bolides acts somewhat like a series of snapshots or a diary of my life between March 2020 and December 2021, and for me evokes geographical and temporal cues that are very specific for that particular point in time. The source material includes underwater recordings of kelp forests, captured by homemade hydrophones, the ululations of grey seal pups, and an improvised percussion performance on plate steel. The compositional methodology was guided by an aural discourse, and the structural decisions throughout the process were informed by the materials as they presented themselves, there were no abstract processes involved. Sound objects were chosen for their gestural and sonic properties, and then further processed using a mixture of real-time interaction facilitated by a Leap motion sensor and a multitouch-surface MIDI controller. Both of these devices were mapped to parameters of various DSP devices, some of which were created using Csound, some of which are native to Ableton Live 11. A series of performances were recorded using this configuration and the results of these gesturally-driven performances were further developed into the library of sound objects that make up this piece.

1. Introduction In 2008, the High Resolution Imaging Science Experiment (HiRISE) on board NASA’s MRO fortuitously captured several discrete clouds of material (Fig.1) in the process of cascading down a steep scarp of the water-ice-rich north polar layered deposits (NPLD). The events were only seen during a period of ~4 weeks, near the onset of northern spring, when the seasonal cover of CO2 is beginning to sublimate from the north polar regions. Russell et al. [1] analyzed the morphology of the clouds, inferring that the particles involved were mechanically analogous to terrestrial “dry, loose snow or dust”, making the events similar to terrestrial “powder avalanches” [2]. HiRISE confirmed the seasonality of these avalanches the following spring, and has been monitoring them (Fig.2) for a total of 7 Mars Years (MY29–MY35). We will present observations from this monitoring. We seek to: (1) quantify the frequency of these events (2) quantify their effect on the mass balance of the NPLD (especially with respect to competing processes such as viscous deformation and other mass-wasting events [3-5], and (3) investigate possible trigger mechanisms. 2. Observations The avalanches often appear as dense clouds of reddish, air-lofted material moving down scarps of the NPLD margins. The scarps are steep (>50º) and appear fractured (Fig.1), and the clouds themselves range in extent from just a few tens of meters to over 200 m. Observations of many avalanche events at different stages allow us to deduce the course of a typical event. Avalanches start at a discrete point on the steep face and remain small and optically thick as they descend (Fig.1a,b). Upon reaching the basal unit they spread outward at speeds of several m/s (measured from color fringing in HiRISE images [1]), become optically thinner, and develop a more diffuse boundary (Fig1.c,d). The avalanches then transition to near-stationary clouds close to, but detached from the scarp, which presumably slowly settle onto the exposed basal unit (Fig.1e). A total of 57 events have been captured in action on the so-called “Discovery Scarp” (Fig.2) since the first five events were captured here in a single HiRISE image. On average, 8 events are captured on this scarp per year, and they tend to occur on its steepest sections (50–70º), and preferentially on SW-facing scarps. Figure 2 shows the location of the Discovery Scarp and all other scarps along the NPLD margins where avalanches have been observed. An average of 20 new events are observed every year. Avalanches have only been observed to occur between Ls 5º and 70º, and thus are an exclusively “springtime” event. This time of year coincides with both the sublimation of seasonal CO2 ice over the north polar region, and with a peak in subsurface compressional stresses in the scarp walls, as shown by [6]. 3. Trigger mechanisms In accordance with the seasonality of the avalanches, trigger mechanisms to consider are (1) sublimation-driven collapse of sections of the scarp wall (material in the avalanches would most likely be a combination of CO2 and surface dust), and (2) thermal stress-driven collapse, similar to exfoliation of granitic domes on Earth [6] (material would mostly be pulverized dusty water ice, i.e. the material that makes up NPLD beds). To examine the first mechanism, we acquired HiRISE images early in the season, before the events occurred. Images of the discovery scarp at Ls 350º (Fig.3a) and Ls 1º appear to show that the CO2 has already sublimated from the steepest parts of the wall by this time. However, CRISM spectra of this location (Fig.3b,c) show absorption bands diagnostic of CO2 until after Ls 50º. Though the bands are weak, their presence suggests CO2 persists until this time. We also used a 1D thermal balance model [7] to calculate the amount of CO2 frost that accumulates on a steep surface throughout the year. With conservative estimates for thermal properties (i.e., assumed an exposed wall of water ice), model results show that on a 50º SW-facing slope, all CO2 frost has sublimated by Ls 10º, matching HiRISE observations but contradicting CRISM. This thermal model is extremely sensitive to dust cover on the scarp wall however, and a few cm of dust can accumulate, and maintain wintertime CO2. It is also possible that the steepness of the scarp makes it difficult to isolate in the CRISM data, and that the absorption bands correspond to influence from adjacent, flatter terrains. 4. Results and Future Work Our study shows that north polar cap avalanches occur frequently on steep, marginal scarps of the NPLD, and likely have a substantial effect in eroding the NPLD. There are contradicting observations of CO2 frost on the steepest areas of the scarps, which we will further investigate with CRISM observations at high-roll angles that view the scarp more head-on. Even if CO2 is present in small amounts on the scarps early in the year, we have found that it is the fractured scarps that show a much higher frequency of avalanches than those that show little to no fracturing. Thus, although CO2 may be present in the clouds mixed with the avalanche material as it moves over the basal unit, a more likely trigger seems to be the springtime peak in compressional stresses that fractures the scarps [6]. In the future, we will quantify the mass wasted by the events with flow models used for terrestrial processes, and further investigate the triggers with improved detail in the thermal and stress models. References [1] Russell et al. (2008) GRL. 35, L23204. [2] McClung and Schaerer (2006), Mountaineers, Seattle Wash. [3] Sori, et al., GRL, 43. [4] Herkenhoff et al. (2020) 7th ICMPSE [5] Fanara et al. 2020, Icarus [6] Byrne et al. (2016), 6th ICMPSE [7] Dundas and Byrne (2010) Icarus 206, 716.

Highlights • First study providing evidence of equivalence of self-collection for SARS-CoV-2 • Self-collection has potential to increase accessibility and detection of SARS-CoV-2 • Self-collection has potential to preserve PPE supplies • Self-collection has potential to reduce exposure to others • Self-collection was easy to perform and preferred by the majority of participants, Objectives To evaluate the reliability of self-collection for SARS-CoV-2 and other respiratory viruses because swab collections for SARS-CoV-2 put health workers at risk of infection and require use of personal protective equipment (PPE). Methods In a prospective study, patients from two states in Australia attending dedicated COVID-19 collection clinics were offered the option to first self-collect (SC) throat and nasal swabs (SCNT) prior to health worker collect (HC) using throat and nasal swabs (Site 1) or throat and nasopharyngeal swabs (Site 2). Samples were analysed for SARS-CoV-2 as well as common respiratory viruses. Concordance of results between methods was assessed using Cohen's kappa (κ) and Cycle threshold (Ct) values were recorded for all positive results as a surrogate measure for viral load. Results Of 236 patients sampled by HC and SC, 25 had SARS-CoV-2 (24 by HC and 25 by SC) and 63 had other respiratory viruses (56 by HC and 58 y SC). SC was highly concordant with HC (κ = 0.890) for all viruses including SARS-CoV-2 and more concordant than HC to positive results by any method (κ = 0.959 vs 0.933). Mean SARS-CoV-2 E-gene and N-gene, rhinovirus and parainfluenza Ct values did not differ between HC and SCNT. Conclusions Self-collection of throat and nasal swabs offers a reliable alternative to health worker collection for the diagnosis of SARS-CoV-2 and other respiratory viruses and provides patients with easier access to testing, reduces exposure of the community and health workers to those being tested and reduces requirement for PPE.

In its polar layered deposits (PLD), Mars possesses a record of its recent climate, analogous to terrestrial ice sheets containing climate records on Earth. Each PLD is greater than 2 ​km thick and contains thousands of layers, each containing information on the climatic and atmospheric state during its deposition, creating a climate archive. With detailed measurements of layer composition, it may be possible to extract age, accumulation rates, atmospheric conditions, and surface activity at the time of deposition, among other important parameters; gaining the information would allow us to “read” the climate record. Because Mars has fewer complicating factors than Earth (e.g. oceans, biology, and human-modified climate), the planet offers a unique opportunity to study the history of a terrestrial planet’s climate, which in turn can teach us about our own planet and the thousands of terrestrial exoplanets waiting to be discovered. During a two-part workshop, the Keck Institute for Space Studies (KISS) hosted 38 Mars scientists and engineers who focused on determining the measurements needed to extract the climate record contained in the PLD. The group converged on four fundamental questions that must be answered with the goal of interpreting the climate record and finding its history based on the climate drivers. The group then proposed numerous measurements in order to answer these questions and detailed a sequence of missions and architecture to complete the measurements. In all, several missions are required, including an orbiter that can characterize the present climate and volatile reservoirs; a static reconnaissance lander capable of characterizing near surface atmospheric processes, annual accumulation, surface properties, and layer formation mechanism in the upper 50 ​cm of the PLD; a network of SmallSat landers focused on meteorology for ground truth of the low-altitude orbiter data; and finally, a second landed platform to access ~500 ​m of layers to measure layer variability through time. This mission architecture, with two landers, would meet the science goals and is designed to save costs compared to a single very capable landed mission. The rationale for this plan is presented below. In this paper we discuss numerous aspects, including our motivation, background of polar science, the climate science that drives polar layer formation, modeling of the atmosphere and climate to create hypotheses for what the layers mean, and terrestrial analogs to climatological studies. Finally, we present a list of measurements and missions required to answer the four major questions and read the climate record. 1. What are present and past fluxes of volatiles, dust, and other materials into and out of the polar regions? 2. How do orbital forcing and exchange with other reservoirs affect those fluxes? 3. What chemical and physical processes form and modify layers? 4. What is the timespan, completeness, and temporal resolution of the climate history recorded in the PLD?

Vinalia and Cerealia Faculae are bright and salt-rich localized areas in Occator crater on Ceres. The predominance of the near-infrared signature of sodium carbonate on these surfaces suggests their original material was a brine. Here we analyze Dawn Framing Camera's images and characterize the surfaces as composed of a central structure, either a possible depression (Vinalia) or a central dome (Cerealia), and a discontinuous mantling. We consider three materials enabling the ascent and formation of the faculae: ice ascent with sublimation and carbonate particle lofting, pure gas emission entraining carbonate particles, and brine extrusion. We find that a mechanism explaining the entire range of morphologies, topographies, as well as the common composition of the deposits is brine fountaining. This process consists of briny liquid extrusion, followed by flash freezing of carbonate and ice particles, particle fallback, and sublimation. Subsequent increase in briny liquid viscosity leads to doming. Dawn observations did not detect currently active water plumes, indicating the frequency of such extrusions is longer than years.

Ice sheets, such as the polar layered deposits (PLDs) of Mars, are of great interest as records of past climate. Smaller outlier ice deposits near the north and south PLDs are likely more sensitive to climate changes and thus may hold information about more recent climate history. However, the southern outlier deposits have largely remained unmapped and unanalyzed. Here, we identify 31 deposits near, but separated from, Mars's south PLDs, all of which are located within impact craters >15 km in diameter. On the basis of morphology, radar analysis, physical similarity to portions of the PLD margin, and overall similarity to previously described deposits in Mars's north polar region, we conclude that these deposits are primarily composed of water ice. An additional 66 craters contain smaller depositional features, some of which may be remnant ice deposits. The 31 outlier ice deposits represent a previously unquantified inventory of water on Mars, with a total volume between 15,000 and 38,000 km3. In addition, we identify five analogous outlier nitrogen ice deposits located within impact craters near Sputnik Planitia, the large nitrogen ice sheet on Pluto. Although important differences exist between Mars and Pluto, broad physical similarities between the two cases suggest that the topography and microclimates of impact craters cause them to be favorable locations for volatile accumulation and/or retention throughout the Solar System.

H2O-rich materials are locally exposed at the surface of Ceres as discovered from infrared reflectance spectra of the Visible and InfraRed mapping spectrometer (VIR) of the Dawn mission. Nine locations on Ceres exhibit diagnostic absorption bands of the H2O molecule at 2.00, 1.65 and 1.28 μm. The detections are all consistent with H2O ice mixed with low-albedo components. All the reported H2O exposures occur at latitudes poleward of 30° in fresh craters near rim shadows, have a surface area < 7 km2, and are associated with one or more surface features such as a morphological flow or landslide, fractures, high albedo, or a pole-facing slope (one case is confirmed to be adjacent to persistent shadow). In four occurrences, these detections are associated with small (< 0.1 km2) high-albedo areas that can be recognized in high-resolution imagery (∼35 m/pixel) from the Framing Camera (FC). Since all these observations are compatible with an H2O-rich subsurface, the replenishment of surficial H2O likely comes from the ice that is present underneath. In four other occurrences, H2O is detected on walls and floors of fresh impact craters, either in the shadow or adjacent to shadows, which suggests that local thermodynamical conditions may also favor the concentration of H2O in these areas.

This study aims to assess the spatial and visible/near-infrared (VNIR) colour/spectral capabilities of the 4-band Colour and Stereo Surface Imaging System (CaSSIS) aboard the ExoMars 2016 Trace Grace Orbiter (TGO). The instrument response functions for the CaSSIS imager was used to resample spectral libraries, modelled spectra and to construct spectrally (i.e., in I/F space) and spatially consistent simulated CaSSIS image cubes of various key sites of interest and for ongoing scientific investigations on Mars. Coordinated datasets from Mars Reconnaissance Orbiter (MRO) are ideal, and specifically used for simulating CaSSIS. The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) provides colour information, while the Context Imager (CTX), and in a few cases the High-Resolution Imaging Science Experiment (HiRISE), provides the complementary spatial information at the resampled CaSSIS unbinned/unsummed pixel resolution (4.6 m/pixel from a 400-km altitude). The methodology used herein employs a Gram-Schmidt spectral sharpening algorithm to combine the ∼18–36 m/pixel CRISM-derived CaSSIS colours with I/F images primarily derived from oversampled CTX images. One hundred and eighty-one simulated CaSSIS 4-colour image cubes (at 18–36 m/pixel) were generated (including one of Phobos) based on CRISM data. From these, thirty-three “fully”-simulated image cubes of thirty unique locations on Mars (i.e., with 4 colour bands at 4.6 m/pixel) were made. All simulated image cubes were used to test both the colour capabilities of CaSSIS by producing standard colour RGB images, colour band ratio composites (CBRCs) and spectral parameters. Simulated CaSSIS CBRCs demonstrated that CaSSIS will be able to readily isolate signatures related to ferrous (Fe2+) iron- and ferric (Fe3+) iron-bearing deposits on the surface of Mars, ices and atmospheric phenomena. Despite the lower spatial resolution of CaSSIS when compared to HiRISE, the results of this work demonstrate that CaSSIS will not only compliment HiRISE-scale studies of various geological and seasonal phenomena, it will also enhance them by providing additional colour and geologic context through its wider and longer full-colour coverage ( $\sim9.4 \times 50$ km), and its increased sensitivity to iron-bearing materials from its two IR bands (RED and NIR). In a few examples, subtle surface changes that were not easily detected by HiRISE were identified in the simulated CaSSIS images. This study also demonstrates the utility of the Gram-Schmidt spectral pan-sharpening technique to extend VNIR colour/spectral capabilities from a lower spatial resolution colour/spectral dataset to a single-band or panchromatic image greyscale image with higher resolution. These higher resolution colour products (simulated CaSSIS or otherwise) are useful as means to extend both geologic context and mapping of datasets with coarser spatial resolutions. The results of this study indicate that the TGO mission objectives, as well as the instrument-specific mission objectives, will be achievable with CaSSIS.

The Colour and Stereo Surface Imaging System (CaSSIS) is the main imaging system onboard the European Space Agency’s ExoMars Trace Gas Orbiter (TGO) which was launched on 14 March 2016. CaSSIS is intended to acquire moderately high resolution (4.6 m/pixel) targeted images of Mars at a rate of 10–20 images per day from a roughly circular orbit 400 km above the surface. Each image can be acquired in up to four colours and stereo capability is foreseen by the use of a novel rotation mechanism. A typical product from one image acquisition will be a $9.5~\mbox{km} \times {\sim}45~\mbox{km}$ swath in full colour and stereo in one over-flight of the target thereby reducing atmospheric influences inherent in stereo and colour products from previous high resolution imagers. This paper describes the instrument including several novel technical solutions required to achieve the scientific requirements.

INTRODUCTION Dwarf planet Ceres’ low average-density (2162 ± 3 kg m −3 ) indicates that it must contain considerable water. Water is likely a key component in the chemical evolution and internal activity of Ceres, possibly resulting in a layer of ice-rich material and perhaps liquid in the mantle. Mineral hydroxides (OH-bearing) and hydrates (H 2 O-bearing), such as clays, carbonates, and various salts, would be created. These hypotheses were supported by the detection of hydroxyl (OH)–rich materials, OH-bearing molecule releases, H 2 O vapor molecules, and haze. However, the presence of H 2 O on the surface has not previously been confirmed. The detection and mapping of H 2 O on Ceres is one objective of the Dawn spacecraft, in orbit around Ceres since March 2015. RATIONALE The purpose of the Dawn space mission at Ceres is to study the geology, geophysics, and composition remotely by means of high-resolution imagery and spectrometry. Dawn’s Visible and InfraRed Mapping Spectrometer (VIR) measures the sunlight scattered by the surface of Ceres in a range of wavelengths between 0.25 and 5.1 μm. The position and shape of absorption features in VIR reflectance spectra are sensitive to the surface mineral and molecular composition. In spectroscopy, absorption bands at 2.0, 1.65, and 1.28 μm are characteristic of vibration overtones in the H 2 O molecule. RESULTS Dawn has detected water-rich surface materials in a 10-km-diameter crater named Oxo, which exhibit all absorption bands that are diagnostic of the H 2 O molecule (see the figure). These spectra are most similar to those of H 2 O ice, but they could also be attributable to hydrated minerals. Oxo crater appears to be geologically very young (~1 million to 10 million years); it has sharp rims and its floor is almost devoid of impacts, suggesting a recent exposure of surface H 2 O. The high latitude and morphology of the Oxo crater protects much of the surface area from direct solar illumination for most of the cerean day, presenting favorable conditions for the stability of water ice or heavily hydrated salts. CONCLUSION Four ways to create or transport H 2 O on Ceres are considered: (i) Exposure of near-surface H 2 O-rich materials by a recent impact or an active landslide seems most consistent with the presence of both mineral hydrates and water ice. (ii) Release of subsurface H 2 O may occur on Ceres, similar to release on comet nuclei, but may never recondense on the surface. (iii) Infall of ice-bearing objects is not likely to deposit water on Ceres, because the H 2 O molecule likely would dissociate upon impact. (iv) Implantation of protons from the solar wind on the surface is not a probable origin of OH on Ceres because of the low flux of solar wind charged particles. We therefore conclude that surface H 2 O or hydrated minerals are the most plausible explanation. Dawn VIR infrared observations of Oxo crater on Ceres demonstrate the detection of H 2 O at the surface. ( A ) Reflectance spectrum collected where absorption bands of H 2 O at 1.28, 1.65, and 2 μm are the strongest (in blue) compared with a laboratory spectrum of H 2 O ice (black). The lab spectrum is scaled and vertically shifted for clarity. ( B ) Perspective view of Oxo crater observed by the Dawn Framing Camera (FC), where the two high-albedo areas right next to the scarps contain H 2 O-rich materials.

We present the scientific case to build a multiple-wavelength, active, near-infrared (NIR) instrument to measure the reflected intensity and polarization characteristics of backscattered radiation from planetary surfaces and atmospheres. We focus on the ability of such an instrument to enhance, perhaps revolutionize, our understanding of climate, volatiles and astrobiological potential of modern-day Mars., 25 pages, 6 figures, 4 tables

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Shallow Radar soundings from the Mars Reconnaissance Orbiter reveal a buried deposit of carbon dioxide (CO2) ice within the south polar layered deposits of Mars with a volume of 9500 to 12,500 cubic kilometers, about 30 times that previously estimated for the south pole residual cap. The deposit occurs within a stratigraphic unit that is uniquely marked by collapse features and other evidence of interior CO2 volatile release. If released into the atmosphere at times of high obliquity, the CO2 reservoir would increase the atmospheric mass by up to 80%, leading to more frequent and intense dust storms and to more regions where liquid water could persist without boiling.

Present-day accumulation in the north polar layered deposits (NPLD) is thought to occur via deposition on the north polar residual cap. Understanding current mass balance in relation to current climate would provide insight into the climatic record of the NPLD. To constrain processes and rates of NPLD resurfacing, a search for craters was conducted using images from the Mars Reconnaissance Orbiter Context Camera. One hundred thirty craters have been identified on the NPLD, 95 of which are located within a region defined to represent recent accumulation. High Resolution Imaging Science Experiment images of craters in this region reveal a morphological sequence of crater degradation that provides a qualitative understanding of processes involved in crater removal. A classification system for these craters was developed based on the amount of apparent degradation and infilling and where possible depth/diameter ratios were determined. The temporal and spatial distribution of crater degradation is interpreted to be close to uniform. Through comparison of the size-frequency distribution of these craters with the expected production function, the craters are interpreted to be an equilibrium population with a crater of diameter D meters having a lifetime of ~30.75D^(1.14) years. Accumulation rates within these craters are estimated at 7.2D^(−0.14) mm/yr, which corresponds to values of ~3–4 mm/yr and are much higher than rates thought to apply to the surrounding flat terrain. The current crater population is estimated to have accumulated in the last ~20 kyr or less.

Secondary crater fields are important stratigraphic markers that can shed light on resurfacing processes that have occurred since their formation. We examine the morphologies of secondary craters formed from the ejection of material from two large impacts on the Martian South Polar Layered Deposits (SPLD): McMurdo crater at 84.5°S, 0°W, and an unnamed impact at 80.8°S, 284°W. The morphologies of these secondary craters allow us to impose constraints on the modification history of the SPLD. We have quantified crater morphologies using data sets from the Mars Global Surveyor and Mars Odyssey missions. We find a complete lack of secondary craters smaller than 300 m in diameter in both crater fields, which implies that at least the upper 30 m of the deposits have been resurfaced since the time of these impacts. Secondary crater depth-to-diameter ratios are low (average of 0.016), indicating that significant degradation has occurred since their emplacement. We find that vertical resurfacing alone is not enough to explain the observed depth-to-diameter distribution and suggest that viscous relaxation of craters coupled with a small amount of vertical resurfacing best fits the data. In the McMurdo field, high depth-to-diameter craters are found preferentially on steeper terrain associated with scarps cutting through the secondary field. This observation suggests that crater modification exhibits a dependence on slope. We comment on possible mechanisms that may explain this observation. The morphologies of secondary craters on the SPLD point to modification processes without lunar parallel and not yet fully modeled for Mars.

An accurate self-consistent way of coregistering the imaging and topographic data sets of the Mars Global Surveyor mission was developed and used to begin a stratigraphic analysis of the northern polar region. A distinct change in the layering style exists at a definite stratigraphic horizon near the base of the north polar layered deposits. Occurrences of the contact between two distinct layered units can be mapped hundreds of kilometers apart at nearly the same Mars Orbiter Laser Altimeter (MOLA) elevation. The lower layered unit has a consistent association with sand dunes, leading to the conclusion that it is an eroding sand-rich deposit that predates most of the overlying north polar layered deposits, which exhibits the expected features of a dust-ice mixture. These results suggest that an areally extensive erg was in existence before the present ice cap and that the present circumpolar erg is likely composed of material reworked from this older deposit. The volume of this lower unit is estimated to be on the order of 10^5 km^3. The presence of this deposit implies that there existed a period in Mars' history when there was no icy polar cap. A dramatic climatic change leading to the deposition of the upper layered (icy) unit in the present-day polar layered deposits represents a major event in Mars' history. However, owing to uncertainties in the mechanics of layered deposits formation, such an event cannot be dated at this time.

Background In Australia two acellular Bordetella pertussis vaccines have replaced the use of a whole cell vaccine. Both of the licensed acellular vaccines contain the following three components; pertussis toxoid, pertussis filamentous haemagglutinin and the 69 kDa pertactin adhesin. One vaccine also contains pertussis fimbriae 2 and 3. Various researchers have postulated that herd immunity due to high levels of pertussis vaccination might be influencing the makeup of endemic B. pertussis populations by selective pressure for strains possessing variants of these genes, in particular the pertactin gene type. Some publications have suggested that B. pertussis variants may be contributing to a reduced efficacy of the existing vaccines and a concomitant re-emergence of pertussis within vaccinated populations. This study was conducted to survey the pertactin and pertussis toxin subunit 1 types from B. pertussis isolates in Queensland, Australia following the introduction of acellular vaccines. Methods Forty-six B. pertussis isolates recovered from Queensland patients between 1999 and 2003 were examined by both DNA sequencing and LightCycler™ real time PCR to determine their pertactin and pertussis toxin subunit 1 genotypes. Results Pertactin typing showed that 38 isolates possessed the prn1 allele, 3 possessed the prn2 allele and 5 possessed the prn3 allele. All forty-six isolates possessed the pertussis toxin ptxS1A genotype. Amongst the circulating B. pertussis population in Queensland, 82.5% of the recovered clinical isolates therefore possessed the prn1/ptxS1A genotype. Conclusion The results of this study compared to historical research on Queensland isolates suggest that B. pertussis pertactin and pertussis toxin variants are not becoming more prevalent in Queensland since the introduction of the acellular vaccines. Current prevalences of pertactin variants are significantly different to that described in a number of other countries with high vaccine coverage. Relative paucity of recovered isolates compared to notified infections, due primarily to non culture based pertussis diagnostics is however a confounding factor in the assessment of variant prevalence.