Drift dynamics in microbial communities and the effective community size.

The structure and diversity of all open microbial communities are shaped by individual births, deaths, speciation and immigration events; the precise timings of these events are unknowable and unpredictable. This randomness is manifest as ecological drift in the population dynamics, the importance of which has been a source of debate for decades. There are theoretical reasons to suppose that drift would be imperceptible in large microbial communities, but this is at odds with circumstantial evidence that effects can be seen even in huge, complex communities. To resolve this dichotomy we need to observe dynamics in simple systems where key parameters, like migration, birth and death rates can be directly measured. We monitored the dynamics in the abundance of two genetically modified strains of Escherichia coli, with tuneable growth characteristics, that were mixed and continually fed into 10 identical chemostats. We demonstrated that the effects of demographic (non-environmental) stochasticity are very apparent in the dynamics. However, they do not conform to the most parsimonious and commonly applied mathematical models, where each stochastic event is independent. For these simple models to reproduce the observed dynamics we need to invoke an 'effective community size', which is smaller than the census community size.

"Was Test Designed for Africans?" Health Literacy and African Immigrants.

BACKGROUND: Immigrants experience barriers to accessing and utilizing health care. Language and cultural differences regarding health and healing impact use of health care. Limited health literacy is associated with decreased preventive health services and is reported among immigrant groups in the USA, but the health literacy of African immigrants is not known. OBJECTIVE: Assess health literacy, its association with engagement in primary care and select sociodemographic variables, and the use of two health literacy measures with African immigrants. METHODS: We conducted a community-based participatory research cross-sectional survey among African immigrants in Massachusetts. Participants completed the Newest Vital Sign, the Health Literacy Skills Instrument, acceptability questionnaires, and a Health Survey. We observed and recorded comments and questions as participants completed the surveys. KEY RESULTS: Out of 75 participants, 60% have limited health literacy. Over 80% are connected to a health care system and comfortable speaking with their doctor/nurse. Education, English proficiency, country of origin, and access to health care are associated with health literacy. Participants found the measures easy to understand but difficult to answer. Observation data revealed unfamiliarity with nutrition labels, cooking measurements, and navigation of internet links, and the need for clarification of select items. CONCLUSIONS: Most African immigrants in this study have limited health literacy despite English proficiency, college education, employment, and connection to a health system. Further research is needed to determine the value of aligning the measurement of health literacy with the cultural-linguistic identities of the population being assessed versus the need to understand their health literacy within the dominant culture.

An Innovative Simulation-based Community-engaged Intervention for Training Research Assistants in Culturally Appropriate Informed Consent.

BACKGROUND: Enrolling under-represented groups in biomedical research remains challenging owing to limited health literacy, historic medical abuses, and mistrust. Addressing such barriers requires scrutiny of informed consent processes and training of research assistants (RAs). Applying simulation methods that are well-established in medical education, Simulation-based Community-engaged Research Intervention for Informed Consent Protocol Testing and Training (SCRIIPTT) engages community members as community advisors (CAs) to train RAs in implementing culturally appropriate approaches, such as addressing difficult issues related to race and power dynamics, into the informed consent training process. OBJECTIVES: To present SCRIIPTT's development, implementation, and preliminary findings. METHODS: Over 12 months, our community-academic partnership 1) introduced SCRIIPTT to the greater community using the Truth & Reconciliation Model, which acknowledges the wrongs of research and offers an apology; 2) deepened understanding of community concerns; 3) developed the intervention; 4) conducted a pilot; and 5) disseminated findings. RESULTS: SCRIIPTT included a comprehensive training manual, scenarios for simulated informed consent encounters, and a 37-item checklist to measure performance. Outcomes include CA and RA satisfaction surveys, and RA performance rating. The checklist adequately measured observable behaviors. RAs reported important gains in knowledge, self-confidence, and cultural competence in conducting informed consent. CAs reported positive experiences, being fully engaged and valued as members of the research team and participants during simulation encounters. CONCLUSIONS: This pilot study demonstrated the feasibility of SCRIIPTT, with preliminary evidence of effectiveness and acceptability. SCRIIPTT offers an innovative approach for community engagement in research training and advancing the skills of RAs in culturally appropriate informed consent.

HIV Stigma, Testing Attitudes and Health Care Access Among African-Born Men Living in the United States.

The purpose of this study was to describe HIV-testing attitudes, HIV related stigma and health care access in African-born men taking part in the African Health Cup (AHC), a soccer tournament held annually to improve HIV awareness and testing. Venue sampling was used to collect survey and qualitative interview data related to HIV-testing attitudes, stigma and experiences associated with the AHC. The sample included 135 survey respondents and 27 interview participants. AHC participants were successfully accessing health care services. Although the AHC was viewed positively, HIV testing rates remain low due to stigma and privacy concerns. This population continues to have misconceptions about HIV transmission and to use condoms inconsistently. The AHC is a successful intervention to engage African-born men in HIV awareness and education. More work is needed to enhance these AHC aspects and address stigma and privacy concerns related to using onsite health screenings. Continuing to develop novel strategies to educate African-born immigrants about HIV is urgently needed.

Barriers to HIV Testing in Black Immigrants to the U.S.

BACKGROUND: Late HIV testing is common among immigrants from sub Saharan Africa and the Caribbean. Since 2010, HIV testing is no longer a required component of immigrant screening examinations or mandatory for immigrants seeking long term residence in the US. Thus, barriers to HIV testing must be addressed. METHODS: Five hundred and fifty-five (555) immigrants completed a barriers-to-HIV testing scale. Univariate and multivariate linear regression were performed to examine predictors of barriers. RESULTS: In multivariate analysis, primary language other than English (ß=2.9, p=.04), lower education (ß=5.8, p=.03), low income [= below $20K/year] (ß=4.6, p=.01), no regular provider (ß=5.2, p=.002) and recent immigration (ß=5.7, p=.0008) were independently associated with greater barriers. Barriers due to health care access, privacy, fatalism, and anticipated stigma were greater for recent versus longer term immigrants. DISCUSSION: Immigrants from sub-Saharan Africa and the Caribbean face significant barriers to HIV testing. Interventions to improve access and timely entry into care are needed.

All black people are not alike: differences in HIV testing patterns, knowledge, and experience of stigma between U.S.-born and non-U.S.-born blacks in Massachusetts.

Non-U.S.-born black individuals comprise a significant proportion of the new diagnoses of HIV in the United States. Concurrent diagnosis (obtaining an AIDS diagnosis in close proximity to an initial diagnosis of HIV) is common in this subpopulation. Although efforts have been undertaken to increase HIV testing among African Americans, little is known about testing patterns among non-U.S.-born black people. A cross-sectional survey was self-administered by 1060 black individuals in Massachusetts (57% non-U.S.-born) to assess self-reported rates of HIV testing, risk factors, and potential barriers to testing, including stigma, knowledge, immigration status, and access to health care. Bivariate analysis comparing responses by birthplace and multivariate logistic regression assessing correlates of recent testing were completed. Non-U.S.-born individuals were less likely to report recent testing than U.S.-born (41.9% versus 55.6%, p<0.0001). Of those who recently tested, the majority did so for immigration purposes, not because of perceived risk. Stigma was significantly higher and knowledge lower among non-U.S.-born individuals. In multivariate analysis, greater length of time since immigration was a significant predictor of nontesting among non-U.S.-born (adjusted odds ratio [AOR] 0.56, 95% confidence interval [CI] 0.36-0.87). Poor health care access and older age were correlated to nontesting in both U.S.- and non-U.S.-born individuals. Our findings indicate that differences in HIV testing patterns exist by nativity. Efforts addressing unique factors limiting testing in non-U.S.-born black individuals are warranted.