Background HIV-1 superinfection occurs at varying frequencies in different at risk populations. Though seroincidence is decreased, in the negative partner of HIV-discordant couples after joint testing and counseling in the Zambia Emory HIV Research Project (ZEHRP) cohort, the annual infection rate remains relatively high at 7-8%. Based on sequencing within the gp41 region of each partner's virus, 24% of new infections between 2004 and 2008 were the result of transmission from a non-spousal partner. Since these seroconvertors and their spouses have disparate epidemiologically-unlinked viruses, there is a risk of superinfection within the marriage. We have, therefore, investigated the incidence and viral origin of superinfection in these couples. Results Superinfection was detected by heteroduplex mobility assay (HMA), degenerate base counting of the gp41 sequence, or by phylogenetic analysis of the longitudinal sequences. It was confirmed by full-length env single genome amplification and phylogenetic analysis. In 22 couples (44 individuals), followed for up to five years, three of the newly infected (initially HIV uninfected) partners became superinfected. In each case superinfection occurred during the first 12 months following initial infection of the negative partner, and in each case the superinfecting virus was derived from a non-spousal partner. In addition, one probable case of intra-couple HIV-1 superinfection was observed in a chronically infected partner at the time of his seroconverting spouse's initial viremia. Extensive recombination within the env gene was observed following superinfection. Conclusions In this subtype-C discordant couple cohort, superinfection, during the first year after HIV-1 infection of the previously negative partner, occurred at a rate similar to primary infection (13.6% [95% CI 5.2-34.8] vs 7.8% [7.1-8.6]). While limited intra-couple superinfection may in part reflect continued condom usage within couples, this and our lack of detecting newly superinfected individuals after one year of primary infection raise the possibility that immunological resistance to intra-subtype superinfection may develop over time in subtype C infected individuals.

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This retrospective chart review of patients at a tertiary referral center compares characteristics and clinical features of patients diagnosed with human rhinovirus (HRV) infection to those of patients with 2009 H1N1 influenza A (pH1N1) during the pandemic respiratory season of 2009 to 2010. Hospital admission rates, intensive care unit (ICU) admissions, and mortality were not statistically different between the HRV and pH1N1 groups; however, more patients in the HRV group were considered immunocompromised.

Bioaerosol samples were collected in an airborne infection isolation room, bathroom, and anteroom of a ventilated patient with coronavirus disease 2019. Twenty-eight samples were negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid, possibly due to the patient being on a closed-circuit ventilator or the efficiency of the air exchanges in the room.

A rare case of acute cholecystitis caused by serogroup O1 Vibrio cholerae in an 83-year-old man is presented. His risk factors for cholecystitis included advanced age and previous abdominal surgeries. The patient had consumed raw oysters several days before presentation. The patient had a poor outcome after admission for this infection, likely due to his underlying illnesses that complicated his hospital course.

Background. Ebola virus (EBOV) infection causes a severe and often fatal disease. Despite the fact that more than 30 000 individuals have acquired Ebola virus disease (EVD), the medical and scientific community still does not have a clear understanding of the mechanisms by which EBOV causes such severe disease. Methods. In this study, 54 biomarkers in plasma samples serially collected from 7 patients with EVD were analyzed in an attempt to define the kinetics of inflammatory modulators. Two clinical disease groups were defined (moderate and severe) based on the need for clinical support. Biomarkers were evaluated for correlation with viremia and clinical disease in an effort to identify pathways that could be useful targets of therapeutic intervention. Results. Patients with severe disease had higher viremia than those with moderate disease. Several biomarkers of immune activation and control were significantly elevated in patients with moderate disease. A series of pro-inflammatory cytokines and chemokines were significantly elevated in patients with severe disease. Conclusions. Biomarkers that were associated with severe EVD were proinflammatory and indicative of endothelial or coagulation cascade dysfunction, as has been seen historically in patients with fatal outcomes. In contrast, biomarkers that were associated with moderate EVD were suggestive of a strong interferon response and control of both innate and adaptive responses. Therefore, clinical interventions that modulate the phenotype and magnitude of immune activation may be beneficial in treating EVD.

An altered intestinal microbiome during chronic human immunodeficiency virus (HIV) infection is associated with mucosal dysfunction, inflammation, and disease progression. We performed a preclinical evaluation of the safety and efficacy of fecal microbiota transplantation (FMT) as a potential therapeutic in HIV-infected individuals. Antiretroviral-treated, chronically simian immunodeficiency virus (SIV)-infected rhesus macaques received antibiotics followed by FMT. The greatest microbiota shift was observed after antibiotic treatment. The bacterial community composition at 2 weeks post-FMT resembled the pre-FMT community structure, although differences in the abundances of minor bacterial populations remained. Immunologically, we observed significant increases in the number of peripheral Th17 and Th22 cells and reduced CD4+ T cell activation in gastrointestinal tissues post-FMT. Importantly, the transplant was well tolerated with no negative clinical side effects. Although this pilot study did not control for the differential contributions of antibiotic treatment and FMT to the observed results, the data suggest that FMT may have beneficial effects that should be further evaluated in larger studies. IMPORTANCE: Due to the immunodeficiency and chronic inflammation that occurs during HIV infection, determination of the safety of FMT is crucial to prevent deleterious consequences if it is to be used as a treatment in the future. Here we used the macaque model of HIV infection and performed FMT on six chronically SIV-infected rhesus macaques on antiretroviral treatment. In addition to providing a preclinical demonstration of the safety of FMT in primates infected with a lentivirus, this study provided a unique opportunity to examine the relationships between alterations to the microbiome and immunological parameters. In this study, we found increased numbers of Th17 and Th22 cells as well as decreased activation of CD4(+) T cells post-FMT, and these changes correlated most strongly across all sampling time points with lower-abundance taxonomic groups and other taxonomic groups in the colon. Overall, these data provide evidence that changes in the microbiome, particularly in terms of diversity and changes in minor populations, can enhance immunity and do not have adverse consequences.

Objectives: Polymerase chain reaction (PCR) has been shown to have an excellent sensitivity and specificity for the detection of Clostridium difficile infection (CDI). Little is known about risk factors for CDI within 14 days of an initial negative test. We sought to determine the characteristics among hospitalized patients associated with risk of short-term acquisition of CDI. Methods: A case-control study was conducted. Cases were patients who converted from PCR negative to positive within 14 days. Each case was matched with three controls. Conditional logistic regression was used to estimate the association between patient characteristics and CDI. Results: Of the 30 patients in our study who had a positive PCR within 14 days of a first negative PCR (cases), 15 (50%) occurred within 7 days of the initial test. Cases had a higher proportion of intravenous vancomycin use in the previous 8 weeks (odds ratio [OR], 3.38; 95% confidence interval [CI], 1.34-8.49) and were less likely to have recent antiviral agent use (OR, 0.30; 95% CI, 0.11-0.83) compared with controls. Conclusions: In hospitalized patients, treatment with intravenous vancomycin within the prior 8 weeks of a first negative PCR test for C difficile is a risk factor for short-term risk for hospital-acquired CDI. Repeat testing guidelines for C difficile PCR should take into consideration patients who may be at high risk for short-term acquisition of CDI.

Background: The safe removal of personal protective equipment (PPE) can limit transmission of serious communicable diseases, but this process poses challenges to healthcare workers (HCWs). Methods: We observed 41 HCWs across 4 Ebola treatment centers in Georgia doffing PPE for simulated patients with serious communicable diseases. Using human factors methodologies, we obtained the details, sequences, and durations of doffing steps; identified the ways each step can fail (failure modes [FMs]); quantified the riskiness of FMs; and characterized the workload of doffing steps. Results: Eight doffing steps were common to all hospitals-removal of boot covers, gloves (outer and inner pairs), the outermost garment, the powered air purifying respirator (PAPR) hood, and the PAPR helmet assembly; repeated hand hygiene (eg, with hand sanitizer); and a final handwashing with soap and water. Across hospitals, we identified 256 FMs during the common doffing steps, 61 of which comprised 19 common FMs. Most of these common FMs were above average in their riskiness at each hospital. At all hospitals, hand hygiene, removal of the outermost garment, and removal of boot covers were above average in their overall riskiness. Measurements of workload revealed that doffing steps were often mentally demanding, and this facet of workload correlated most strongly with the effortfulness of a doffing step. Conclusions: We systematically identified common points of concern in protocols for doffing high-level PPE. Addressing FMs related to hand hygiene and the removal of the outermost garment, boot covers, and PAPR hood could improve HCW safety when doffing high-level PPE. We identified ways that doffing protocols for high-level personal protective equipment may fail to protect healthcare workers. Hand hygiene, removing the outermost garment, boot covers, and respirator hood harbored the greatest risk and failed in similar ways across different hospitals.

Background: Few data exist to guide the physical design of biocontainment units, particularly the doffing area. This can impact the contamination risk of healthcare workers (HCWs) during doffing of personal protective equipment (PPE). Methods: In phase I of our study, we analyzed simulations of a standard patient care task with 56 trained HCWs focusing on doffing of high-level PPE. In phase II, using a rapid cycle improvement approach, we tested different balance AIDS and redesigned doffing area layouts with 38 students. In phase III, we tested 1 redesigned layout with an additional 10 trained HCWs. We assessed the effectiveness of design changes on improving the HCW performance (measured by occurrence and number of risky behaviors) and reducing the physical and cognitive load by comparing the results from phase I and phase III. Results: The physical load was highest when participants were removing their shoe covers without any balance aid; the use of a chair required the lowest physical effort, followed by horizontal and vertical grab bars. In the revised design (phase III), the overall performance of participants improved. There was a significant decrease in the number of HCW risky behaviors (P =. 004); 5 risky behaviors were eliminated and 2 others increased. There was a significant decrease in physical load when removing disposable shoe covers (P =. 04), and participants reported a similar workload in the redesigned doffing layout (P =. 43). Conclusions: Through optimizing the design and layout of the doffing space, we reduced risky behaviors of HCWs during doffing of high-level PPE.