Associations between antiretroviral regimen and changes in blood pressure: results from the D2EFT study.

In this randomised, controlled study in 14 low- and middle-income countries, individuals taking dolutegravir with darunavir/ritonavir for 48 weeks had a greater increase in systolic and diastolic blood pressure than individuals taking two nucleoside reverse transcriptase with darunavir/ritonavir. The difference remained significant after controlling for confounding factors including weight gain.

Clinical and laboratory features of COVID-19 illness and outcomes in immunocompromised individuals during the first pandemic wave in Sydney, Australia.

People with immunocompromising conditions are at increased risk of SARS-CoV-2 infection and mortality, however early in the pandemic it was challenging to collate data on this heterogenous population. We conducted a registry study of immunocompromised individuals with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection from March-October 2020 in Sydney, Australia to understand clinical and laboratory outcomes in this population prior to the emergence of the Delta variant. 27 participants were enrolled into the study including people with a haematologic oncologic conditions (n = 12), secondary immunosuppression (N = 8) and those with primary or acquired immunodeficiency (i.e. HIV; N = 7). All participants had symptomatic COVID-19 with the most common features being cough (64%), fever (52%) and headache (40%). Five patients demonstrated delayed SARS-CoV-2 clearance lasting three weeks to three months. The mortality rate in this study was 7% compared to 1.3% in the state of New South Wales Australia during the same period. This study provides data from the first eight months of the pandemic on COVID-19 outcomes in at-risk patient groups.

Characteristics of Human Immunodeficiency Virus (HIV) Seroconversions in a Large Prospective Implementation Cohort Study of Oral HIV Preexposure Prophylaxis in Men Who Have Sex with Men (EPIC-NSW).

BACKGROUND: Most human immunodeficiency virus (HIV) seroconversions in people who have initiated preexposure prophylaxis (PrEP) occur in the context of insufficient adherence. We describe participants who seroconverted after being dispensed PrEP in a large PrEP implementation study in Australia. METHODS: Expanded PrEP Implementation in Communities in New South Wales was an implementation study of daily oral PrEP in individuals aged ≥18 years at high risk for acquiring HIV. HIV seroconversions were defined as a positive HIV test by either antigen, antibody, or detectable HIV viral load after enrollment. Insufficient adherence, measured by dispensing logs or participant self-report, was defined as <4 PrEP doses per week. RESULTS: A total of 9596 participants were enrolled and dispensed PrEP between 1 March 2016 and 30 April 2018; 30 were diagnosed with HIV by 31 March 2019. The median (interquartile range [IQR]) age was 31 (25-38) years, all identified as male, 29 (97%) identified as gay or homosexual, and 20 (69%) lived in a postcode with a low concentration of gay male residents. The median (IQR) days from first PrEP dispensing to diagnosis was 409 (347-656). There was no evidence that participants who seroconverted had been sufficiently adherent to PrEP. Nineteen (63%) participants who seroconverted were diagnosed with chlamydia, gonorrhoea, syphilis, or new hepatitis C infection. One participant had resistance to emtricitabine (M184V mutation) at diagnosis. CONCLUSIONS: Participants who seroconverted were insufficiently adherent to PrEP despite being at high risk for acquiring HIV. Understanding the reasons for poor PrEP adherence in individuals who subsequently acquire HIV is critical to improving PrEP effectiveness.

Multispecies Outbreak of Nocardia Infections in Heart Transplant Recipients and Association with Climate Conditions, Australia.

A multispecies outbreak of Nocardia occurred among heart transplant recipients (HTR), but not lung transplant recipients (LTR), in Sydney, New South Wales, Australia, during 2018-2019. We performed a retrospective review of 23 HTR and LTR who had Nocardia spp. infections during June 2015-March 2021, compared risk factors for Nocardia infection, and evaluated climate conditions before, during, and after the period of the 2018-2019 outbreak. Compared with LTR, HTR had a shorter median time from transplant to Nocardia diagnosis, higher prevalence of diabetes, greater use of induction immunosuppression with basiliximab, and increased rates of cellular rejection before Nocardia diagnosis. During the outbreak, Sydney experienced the lowest monthly precipitation and driest surface levels compared with time periods directly before and after the outbreak. Increased immunosuppression of HTR compared with LTR, coupled with extreme weather conditions during 2018-2019, may explain this outbreak of Nocardia infections in HTR.

The Association of Baseline Plasma SARS-CoV-2 Nucleocapsid Antigen Level and Outcomes in Patients Hospitalized With COVID-19.

BACKGROUND: Levels of plasma SARS-CoV-2 nucleocapsid (N) antigen may be an important biomarker in patients with COVID-19 and enhance our understanding of the pathogenesis of COVID-19. OBJECTIVE: To evaluate whether levels of plasma antigen can predict short-term clinical outcomes and identify clinical and viral factors associated with plasma antigen levels in hospitalized patients with SARS-CoV-2. DESIGN: Cross-sectional study of baseline plasma antigen level from 2540 participants enrolled in the TICO (Therapeutics for Inpatients With COVID-19) platform trial from August 2020 to November 2021, with additional data on day 5 outcome and time to discharge. SETTING: 114 centers in 10 countries. PARTICIPANTS: Adults hospitalized for acute SARS-CoV-2 infection with 12 days or less of symptoms. MEASUREMENTS: Baseline plasma viral N antigen level was measured at a central laboratory. Delta variant status was determined from baseline nasal swabs using reverse transcriptase polymerase chain reaction. Associations between baseline patient characteristics and viral factors and baseline plasma antigen levels were assessed using both unadjusted and multivariable modeling. Association between elevated baseline antigen level of 1000 ng/L or greater and outcomes, including worsening of ordinal pulmonary scale at day 5 and time to hospital discharge, were evaluated using logistic regression and Fine-Gray regression models, respectively. RESULTS: Plasma antigen was below the level of quantification in 5% of participants at enrollment, and 1000 ng/L or greater in 57%. Baseline pulmonary severity of illness was strongly associated with plasma antigen level, with mean plasma antigen level 3.10-fold higher among those requiring noninvasive ventilation or high-flow nasal cannula compared with room air (95% CI, 2.22 to 4.34). Plasma antigen level was higher in those who lacked antispike antibodies (6.42 fold; CI, 5.37 to 7.66) and in those with the Delta variant (1.73 fold; CI, 1.41 to 2.13). Additional factors associated with higher baseline antigen level included male sex, shorter time since hospital admission, decreased days of remdesivir, and renal impairment. In contrast, race, ethnicity, body mass index, and immunocompromising conditions were not associated with plasma antigen levels. Plasma antigen level of 1000 ng/L or greater was associated with a markedly higher odds of worsened pulmonary status at day 5 (odds ratio, 5.06 [CI, 3.41 to 7.50]) and longer time to hospital discharge (median, 7 vs. 4 days; subhazard ratio, 0.51 [CI, 0.45 to 0.57]), with subhazard ratios similar across all levels of baseline pulmonary severity. LIMITATIONS: Plasma samples were drawn at enrollment, not hospital presentation. No point-of-care test to measure plasma antigen is currently available. CONCLUSION: Elevated plasma antigen is highly associated with both severity of pulmonary illness and clinically important patient outcomes. Multiple clinical and viral factors are associated with plasma antigen level at presentation. These data support a potential role of ongoing viral replication in the pathogenesis of SARS-CoV-2 in hospitalized patients. PRIMARY FUNDING SOURCE: U.S. government Operation Warp Speed and National Institute of Allergy and Infectious Diseases.

Overcoming barriers to HIV pre-exposure prophylaxis (PrEP) coverage in Australia among Medicare-ineligible people at risk of HIV: results from the MI-EPIC clinical trial.

Background Overseas-born people who are ineligible for government-subsidised health care experience barriers to accessing HIV pre-exposure prophylaxis (PrEP) in Australia. This study aimed to assess a program providing free PrEP to overseas-born adults at risk of acquiring HIV. Methods Medicare-Ineligible Expanded Implementation in Communities (MI-EPIC) was a single-arm, open-label trial of daily tenofovir disoproxil fumarate/emtricitabine as PrEP. Six clinics recruited Medicare-ineligible adults who met HIV risk criteria in New South Wales, Australia. We recorded data on HIV and sexually transmitted infection (STI) diagnoses, and PrEP dispensing from July 2019 to June 2020. PrEP adherence as a medication possession ratio (MPR) was calculated as pills dispensed divided by days. We administered an optional survey on behaviours and attitudes to PrEP and sexual health. Results The 221 participants (206 men; 93.2%) had a median age of 29years (IQR 26-34). Participants were mostly born in Asia (53.4%), Latin America or the Caribbean (25.3%), or Europe (10.9%). Adherence was high; 190 participants (86.0%) had an MPR of >60%. Of 121 survey participants, 42 (34.7%) completed the survey in a language other than English. Of participants who had not used PrEP in the 6months before enrolment (n=45, 37.2%), the most common reasons were cost (n=22, 48.9%), and lack of knowledge about accessing PrEP (n=20, 44.4%). Conclusions Medicare-ineligible people at risk of HIV demonstrate high adherence when given access to free PrEP and translated information. Increasing PrEP awareness and reducing barriers to accessing PrEP in this high-risk population should be priorities in HIV prevention.

Long-term protection from HIV infection with oral HIV pre-exposure prophylaxis in gay and bisexual men: findings from the expanded and extended EPIC-NSW prospective implementation study.

BACKGROUND: Daily pre-exposure prophylaxis (PrEP) is effective in preventing HIV, but few long-term data are available on effectiveness and adherence in real-world settings. Here, we report trends in HIV incidence over 3 years in individuals at high risk who were prescribed PrEP in New South Wales (NSW), as well as adherence before the transition to subsidised PrEP. METHODS: Expanded PrEP Implementation in Communities-New South Wales (EPIC-NSW) was a pragmatic, prospective, single-arm, implementation study of daily, oral PrEP in 31 sites (sexual health clinics, general practices, and a hospital) in NSW, Australia. Eligible participants were HIV-negative adults (aged ≥18 years) who were at high risk of HIV infection as defined in local PrEP guidelines. Participants were prescribed coformulated (once-daily, oral tablet) tenofovir disoproxil fumarate (300 mg) and emtricitabine (200 mg) as HIV PrEP and were followed up with HIV testing, sexually transmitted infection testing, and PrEP dispensing. Originally planned for 3700 participants followed for 1 year, the study was expanded so that all eligible participants in the state could obtain PrEP and extended until publicly subsidised PrEP became available in Australia. The primary outcome was new HIV infection among all participants who were dispensed PrEP at least once and had at least one follow-up HIV test result. Adherence was estimated by medication possession ratio (MPR), defined as the proportion of PrEP pills dispensed in 90 days, assuming daily dosing. This study is registered with ClinicalTrials.gov, NCT02870790. FINDINGS: Between March 1, 2016, and April 30, 2018, we enrolled 9709 participants. 9596 participants were dispensed PrEP, of whom 9448 (98·3%) were gay or bisexual men. Participants were followed up until March 31, 2019, with at least one follow-up HIV test available in 9520 (99·2%) participants. Mean MPR declined from 0·93 to 0·64 from the first to the ninth quarter. There were 30 HIV seroconversions over 18 628 person-years, an incidence of 1·61 per 1000 person-years (95% CI 1·13-2·30). Being younger, living in a postcode with fewer gay men, reporting more risk behaviours at baseline, and having an MPR of less than 0·6 were each univariately associated with increased HIV incidence. In the final year of follow-up, when PrEP was mostly purchased rather than provided free by the study, HIV incidence remained low at 2·24 per 1000 person-years (1·46-3·44). INTERPRETATION: HIV incidence remained low over up to 3 years of follow-up, including during a transition from study-provided to publicly subsidised PrEP. In a setting of affordable PrEP and associated health-care services, very low HIV incidence of 1 to 2 per 1000 person-years can be maintained in gay and bisexual men who were previously at high risk. FUNDING: New South Wales Ministry of Health, Australian Capital Territory Health Directorate, Gilead Sciences.

HIV is associated with an increased risk of age-related clonal hematopoiesis among older adults.

People with human immunodeficiency virus (HIV) have higher rates of certain comorbidities, particularly cardiovascular disease and cancer, than people without HIV1-5. In view of observations that somatic mutations associated with age-related clonal hematopoiesis (CH) are linked to similar comorbidities in the general population6-10, we hypothesized that CH may be more prevalent in people with HIV. To address this issue, we established a prospective cohort study, the ARCHIVE study (NCT04641013), in which 220 HIV-positive and 226 HIV-negative participants aged 55 years or older were recruited in Australia. Demographic characteristics, clinical data and peripheral blood were collected to assess the presence of CH mutations and to identify potential risk factors for and clinical sequelae of CH. In total, 135 CH mutations were identified in 100 (22.4%) of 446 participants. CH was more prevalent in HIV-positive participants than in HIV-negative participants (28.2% versus 16.8%, P = 0.004), overall and across all age groups; the adjusted odds ratio for having CH in those with HIV was 2.16 (95% confidence interval 1.34-3.48, P = 0.002). The most common genes mutated overall were DNMT3A (47.4%), TET2 (20.0%) and ASXL1 (13.3%). CH and HIV infection were independently associated with increases in blood parameters and biomarkers associated with inflammation. These data suggest a selective advantage for the emergence of CH in the context of chronic infection and inflammation related to HIV infection.

Comorbidity Medications Are Dispensed to More People Receiving Antiretroviral Therapy for HIV Compared with the General Population in Australia.

Medical comorbidities occur in more persons with HIV than without HIV. We used a nationally representative 10% sample of 2016 Pharmaceutical Benefits Scheme (PBS) dispensing data to compare the proportions of antiretroviral therapy (ART)-purchasing and non-ART-purchasing patients who also purchased prescriptions for medical comorbidities. Each patient who purchased ART was compared with two gender- and age group-matched patients who did not purchase ART in the same year. We calculated the proportions of patients who also purchased coprescriptions used for hypertension, dyslipidemia, diabetes, cancer, low bone mineral density, and mental health, defined using PBS medication coding categories, and the resulting odds ratios. A total of 1,973 ART-purchasing patients in our sample were matched to 3,946 non-ART-purchasing patients. Compared with non-ART-purchasing patients, a greater proportion of ART-purchasing patients also purchased medications for dyslipidemia (19.8% vs. 16.6%; p-value = .003), low bone mineral density (1.5% vs. 0.8%; p-value = .02), and mental health (29.1% vs. 15.3%; p-value < .0001); a lower proportion purchased diabetes medications (4.8% vs. 6.5%; p-value = .009). These differences remained when our analysis was restricted to persons >55 years of age. Rates of multimorbidity (dispensed ≥2 medications for chronic conditions) were also higher among ART-purchasing patients (19.0% vs. 15.9%; p-value = .003). Using a nationally representative sample of prescription dispensing data, we found that higher proportions of ART-purchasing patients purchased coprescriptions for common comorbidities compared with non-ART-purchasing patients. Our finding that ART-purchasing patients purchased fewer diabetes medications is surprising, but may reflect differences in population characteristics between our two groups.

HIV treatment regimens and adherence to national guidelines in Australia: an analysis of dispensing data from the Australian pharmaceutical benefits scheme.

BACKGROUND: Treatment guidelines for antiretroviral therapy (ART) have evolved to emphasize newer regimens that address ageing-related comorbidities. Using national Australian dispensing data we compare ART regimens with Australian HIV treatment guidelines in the context of treated comorbidities. METHODS: The study population included all individuals in a 10% sample of national data from the Australian Pharmaceutical Benefits Scheme (PBS) who purchased a prescription of ART during 2016. We defined each patient's most recently dispensed ART regimen and characterized them to evaluate regimen complexity and adherence to national HIV treatment guidelines. We then analyzed ART regimens in the context of other co-prescriptions purchased for defined comorbidities. RESULTS: The 1995 patients in our sample purchased 212 different ART regimens during 2016; 1524 (76.4%) purchased one of the top ten most common regimens of which 62.3% were integrase strand transfer inhibitor-based. Among the 1786 (90%) patients that purchased the most common regimens, 83.7% purchased a regimen recommended by the guidelines for initial antiretroviral therapy and 11.4% purchased antiretrovirals that are not recommended for initial therapy; < 1% of the entire cohort purchased medications not recommended for use. While most patients purchased optimal ART regimens with low potential for significant drug interactions, regimen choices in the setting of risk factors for heart disease, renal disease and low bone mineral density appeared suboptimal. CONCLUSIONS: Australian HIV providers are prescribing ART regimens in accordance with updated treatment guidelines, but could further optimize regimens in the setting of important medical comorbidities.

Benefit of Early versus Deferred Antiretroviral Therapy on Progression of Liver Fibrosis among People with HIV in the START Randomized Trial.

The role of antiretroviral therapy (ART) in reducing or contributing to liver fibrosis in persons with human immunodeficiency virus (HIV) is unclear. We evaluated participants in the Strategic Timing of AntiRetroviral Treatment (START) trial for liver fibrosis using the AST to Platelet Ratio Index (APRI) and Fibrosis-4 Index (FIB-4), and assessed for a benefit of early versus delayed ART on liver fibrosis progression. ART-naïve persons with high CD4 counts (>500 cells/µL) from 222 clinical sites in 35 countries were randomized to receive ART either at study enrollment (immediate treatment arm) or when their CD4 count fell below 350 cells/µL (deferred treatment arm). The following outcomes were evaluated: fibrosis (APRI > 0.5 or FIB-4 > 1.45), significant fibrosis (APRI > 1.5 or FIB-4 > 3.25), hepatic flare, and resolution of elevated APRI and FIB-4 scores. Of the 4,684 enrolled into the START study, 104 did not have APRI or FIB-4 results and were excluded. Among 4,580 participants (2,273 immediate treatment; 2,307 deferred treatment), the median age was 36 years, 26.9% were female, and 30.4% were black. Three percent had an alcoholism or substance abuse history, 6.4% had hepatitis B and/or C, and 1.1% had significant fibrosis at baseline. The median CD4 count was 651, and 5.3% had HIV RNA ≤ 200. Immediate arm participants were at lower risk of developing increased fibrosis scores than deferred arm participants (hazard ratio [HR] = 0.66; 95% confidence interval [CI] = 0.57-0.78; P < 0.001) and more likely to have resolution of elevated baseline scores (HR 1.6; 95% CI 1.3-1.9; P < 0.001). Conclusions: Significant liver fibrosis was rare among ART-naïve HIV-positive persons with high CD4 counts. Our findings suggest a benefit of early ART in preventing the development of liver fibrosis.

Population-level effectiveness of rapid, targeted, high-coverage roll-out of HIV pre-exposure prophylaxis in men who have sex with men: the EPIC-NSW prospective cohort study.

BACKGROUND: HIV pre-exposure prophylaxis (PrEP) is highly effective in men who have sex with men (MSM) at the individual level, but data on population-level impact are lacking. We examined whether rapid, targeted, and high-coverage roll-out of PrEP in an MSM epidemic would reduce HIV incidence in the cohort prescribed PrEP and state-wide in Australia's most populous state, New South Wales. METHODS: The Expanded PrEP Implementation in Communities-New South Wales (EPIC-NSW) study is an implementation cohort study of daily co-formulated tenofovir disoproxil fumarate and emtricitabine as HIV PrEP. We recruited high-risk gay men in a New South Wales-wide network of 21 clinics. We report protocol-specified co-primary outcomes at 12 months after recruitment of the first 3700 participants: within-cohort HIV incidence; and change in population HIV diagnoses in New South Wales between the 12-month periods before and after PrEP roll-out. The study is registered with ClinicalTrials.gov, number NCT02870790. FINDINGS: We recruited 3700 participants in the 8 months between March 1, 2016, and Oct 31, 2016. 3676 (99%) were men, 3534 (96%) identified as gay, and 149 (4%) as bisexual. Median age was 36 years (IQR 30-45 years). Overall, 3069 (83%) participants attended a visit at 12 months or later. Over 4100 person-years, two men became infected with HIV (incidence 0·048 per 100 person-years, 95% CI 0·012-0·195). Both had been non-adherent to PrEP. HIV diagnoses in MSM in New South Wales declined from 295 in the 12 months before PrEP roll-out to 221 in the 12 months after (relative risk reduction [RRR] 25·1%, 95% CI 10·5-37·4). There was a decline both in recent HIV infections (from 149 to 102, RRR 31·5%, 95% CI 11·3 to 47·3) and in other HIV diagnoses (from 146 to 119, RRR 18·5%, 95% CI -4·5 to 36·6). INTERPRETATION: PrEP implementation was associated with a rapid decline in HIV diagnoses in the state of New South Wales, which was greatest for recent infections. As part of a combination prevention approach, rapid, targeted, high-coverage PrEP implementation is effective to reduce new HIV infections at the population level. FUNDING: New South Wales Ministry of Health, Gilead Sciences.

Performance of the G4 Xpert® MTB/RIF assay for the detection of Mycobacterium tuberculosis and rifampin resistance: a retrospective case-control study of analytical and clinical samples from high- and low-tuberculosis prevalence settings.

BACKGROUND: The Xpert® MTB/RIF (Xpert) assay is a rapid PCR-based assay for the detection of Mycobacterium tuberculosis complex DNA (MTBc) and mutations associated with rifampin resistance (RIF). An updated version introduced in 2011, the G4 Xpert, included modifications to probe B and updated analytic software. METHODS: An analytical study was performed to assess Xpert detection of mutations associated with rifampin resistance in rifampin-susceptible and -resistant isolates. A clinical study was performed in which specimens from US and non-US persons suspected of tuberculosis (TB) were tested to determine Xpert performance characteristics. All specimens underwent smear microscopy, mycobacterial culture, conventional drug-susceptibility testing and Xpert testing; DNA from isolates with discordant rifampin resistance results was sequenced. RESULTS: Among 191 laboratory-prepared isolates in the analytical study, Xpert sensitivity for detection of rifampin resistance associated mutations was 97.7% and specificity was 90.8%, which increased to 99.0% after DNA sequencing analysis of the discordant samples. Of the 1,096 subjects in the four clinical studies, 49% were from the US. Overall, Xpert detected MTBc in 439 of 468 culture-positive specimens for a sensitivity of 93.8% (95% confidence interval [CI]: 91.2%-95.7%) and did not detect MTBc in 620 of 628 culture-negative specimens for a specificity of 98.7% (95% CI: 97.5%-99.4%). Sensitivity was 99.7% among smear-positive cases, and 76.1% among smear-negative cases. Non-determinate MTBc detection and false-positive RIF resistance results were low (1.2 and 0.9%, respectively). CONCLUSIONS: The updated Xpert assay retained the high sensitivity and specificity of the previous assay versions and demonstrated low rates of non-determinate and RIF resistance false positive results.

Bridging the gap between evidence and policy for infectious diseases: How models can aid public health decision-making.

The dominant approach to decision-making in public health policy for infectious diseases relies heavily on expert opinion, which often applies empirical evidence to policy questions in a manner that is neither systematic nor transparent. Although systematic reviews are frequently commissioned to inform specific components of policy (such as efficacy), the same process is rarely applied to the full decision-making process. Mathematical models provide a mechanism through which empirical evidence can be methodically and transparently integrated to address such questions. However, such models are often considered difficult to interpret. In addition, models provide estimates that need to be iteratively re-evaluated as new data or considerations arise. Using the case study of a novel diagnostic for tuberculosis, a framework for improved collaboration between public health decision-makers and mathematical modellers that could lead to more transparent and evidence-driven policy decisions for infectious diseases in the future is proposed. The framework proposes that policymakers should establish long-term collaborations with modellers to address key questions, and that modellers should strive to provide clear explanations of the uncertainty of model structure and outputs. Doing so will improve the applicability of models and clarify their limitations when used to inform real-world public health policy decisions.

Improving the sensitivity of the Xpert MTB/RIF assay on sputum pellets by decreasing the amount of added sample reagent: a laboratory and clinical evaluation.

The Xpert MTB/RIF (Xpert) assay permits rapid near-patient detection of Mycobacterium tuberculosis in sputum; however, the test sensitivity remains suboptimal in paucibacillary specimens that are negative for acid-fast bacilli using smear microscopy. Xpert testing includes dilution with sample reagent, and when processed sputum pellets are tested, the recommended sample reagent/pellet ratio is 3:1. We evaluated whether a decreased sample reagent/pellet ratio of 2:1 increased Xpert sensitivity compared to the recommended 3:1. The limit of detection was determined by inoculating serial dilutions of M. tuberculosis into sputum samples, preparing sputum pellets, and testing each pellet by Xpert at both sample reagent ratios. Processed sputum pellets obtained from M. tuberculosis culture-positive clinical specimens were also tested by Xpert at both ratios. Among spiked sputum pellets, the limit of detection was 1,478 CFU/ml (95% confidence interval [CI], 1,211 to 1,943) at a 3:1 ratio and decreased to 832 CFU/ml (95% CI, 671 to 1,134) at 2:1. The proportion of specimens in which M. tuberculosis was detected was greater at 2:1 than at 3:1 for almost all numbers of CFU/ml; this difference was most prominent at lower numbers of CFU/ml. Among 134 concentrated sputum pellets from the clinical study, the sensitivity of Xpert at 2:1 was greater than at 3:1 overall (80% versus 72%; P=0.03) and for smear-negative specimens (67% versus 58%; P=0.12). For Xpert testing of sputum pellets, using a lower sample reagent/pellet ratio increased M. tuberculosis detection, especially for paucibacillary specimens. Our study supports use of a 2:1 sample reagent/pellet dilution for Xpert testing of sputum pellets.

Child, household, and caregiver characteristics associated with hospitalization for influenza among children 6-59 months of age: an emerging infections program study.

BACKGROUND: Young children are at increased risk of severe outcomes from influenza illness, including hospitalization. We conducted a case-control study to identify risk factors for influenza-associated hospitalizations among children in US Emerging Infections Program sites. METHODS: Cases were children 6-59 months of age hospitalized for laboratory-confirmed influenza infections during 2005-2008. Age- and zip-code-matched controls were enrolled. Data on child, caregiver and household characteristics were collected from parents and medical records. Conditional logistic regression was used to identify independent risk factors for hospitalization. RESULTS: We enrolled 290 (64%) of 454 eligible cases and 1089 (49%) of 2204 eligible controls. Risk for influenza hospitalization increased with maternal age <26 years [odds ratio (OR): 1.8, 95% confidence interval (CI): 1.1-2.9]; household income below the poverty threshold (OR: 2.2, 95% CI: 1.4-3.6); smoking by >50% of household members (OR: 2.9, 95% CI: 1.4-6.6); lack of household influenza vaccination (OR: 1.8, 95% CI: 1.2-2.5) and presence of chronic illnesses, including hematologic/oncologic (OR: 11.8, 95% CI: 4.5-31.0), pulmonary (OR: 2.9, 95% CI: 1.9-4.4) and neurologic (OR: 3.8, 95% CI: 1.6-9.2) conditions. Full influenza immunization decreased the risk among children 6-23 months of age (OR: 0.5, 95% CI: 0.3-0.9) but not among those 24-59 months of age (OR: 1.5, 95% CI: 0.8-3.0; P value for difference = 0.01). CONCLUSIONS: Chronic illnesses, young maternal age, poverty, household smoking and lack of household influenza vaccination increased the risk of influenza hospitalization. These characteristics may help providers to identify young children who are at greatest risk for severe outcomes from influenza illness.

Clinical and virologic outcomes in patients with oseltamivir-resistant seasonal influenza A (H1N1) infections: results from a clinical trial.

Nineteen patients with oseltamivir-resistant seasonal influenza A (H1N1) infections were randomized to receive oseltamivir or placebo. Nasopharyngeal swabs were obtained, and clinical and virologic outcomes were compared, stratified by early or late treatment. Neuraminidase inhibition assay and pyrosequencing for H275Y confirmed resistance. Twelve (63%) patients received oseltamivir; 8 (67%) received late treatment. Seven (37%) patients received placebo; 6 (86%) presented >48 hours after onset. Time to 50% decrease in symptom severity, complete symptom resolution, and first negative culture were shortest among the early treatment group. While sample size prohibits a strong conclusion, future studies should evaluate for similar trends.