Publications

BACKGROUND

Trichomonas vaginalis is the causative agent of human trichomoniasis, the most common non-viral sexually transmitted infection world-wide. Despite its prevalence, little is known about the genetic diversity and population structure of this haploid parasite due to the lack of appropriate tools. The development of a panel of microsatellite makers and SNPs from mining the parasite's genome sequence has paved the way to a global analysis of the genetic structure of the pathogen and association with clinical phenotypes.

METHODOLOGY/PRINCIPAL FINDINGS

Here we utilize a panel of T. vaginalis-specific genetic markers to genotype 235 isolates from Mexico, Chile, India, Australia, Papua New Guinea, Italy, Africa and the United States, including 19 clinical isolates recently collected from 270 women attending New York City sexually transmitted disease clinics. Using population genetic analysis, we show that T. vaginalis is a genetically diverse parasite with a unique population structure consisting of two types present in equal proportions world-wide. Parasites belonging to the two types (type 1 and type 2) differ significantly in the rate at which they harbor the T. vaginalis virus, a dsRNA virus implicated in parasite pathogenesis, and in their sensitivity to the widely-used drug, metronidazole. We also uncover evidence of genetic exchange, indicating a sexual life-cycle of the parasite despite an absence of morphologically-distinct sexual stages.

CONCLUSIONS/SIGNIFICANCE

Our study represents the first robust and comprehensive evaluation of global T. vaginalis genetic diversity and population structure. Our identification of a unique two-type structure, and the clinically relevant phenotypes associated with them, provides a new dimension for understanding T. vaginalis pathogenesis. In addition, our demonstration of the possibility of genetic exchange in the parasite has important implications for genetic research and control of the disease.

BACKGROUND

Despite federal laws requiring language access in healthcare settings, most US pharmacies are unable to provide prescription (Rx) medication instructions to limited English proficient (LEP) patients in their native language.

OBJECTIVE

To evaluate the efficacy of health literacy-informed, multilingual Rx instructions (the ConcordantRx instructions) to improve Rx understanding, regimen dosing and regimen consolidation in comparison to standard, language-concordant Rx instructions.

DESIGN

Randomized, experimental evaluation.

PARTICIPANTS

Two hundred and two LEP adults speaking five non-English languages (Chinese, Korean, Russian, Spanish, Vietnamese), recruited from nine clinics and community organizations in San Francisco and Chicago.

INTERVENTION

Subjects were randomized to review Rx bottles with either ConcordantRx or standard instructions.

MAIN MEASURES

Proper demonstration of common prescription label instructions for single and multi-drug medication regimens. Regimen consolidation was assessed by determining how many times per day subjects would take medicine for a multi-drug regimen.

KEY RESULTS

Subjects receiving the ConcordantRx instructions demonstrated significantly greater Rx understanding, regimen dosing and regimen consolidation in comparison to those receiving standard instructions (incidence rate ratio [IRR]: 1.25, 95 % confidence interval [CI]: 1.06-1.48; P= 0.007 for Rx understanding, IRR: 1.19, 95 % CI: 1.03-1.39; P= 0.02 for regimen dosing and IRR: 0.76, 95 % CI: 0.64-0.90; P= 0.001 for regimen consolidation). In most cases, instruction type was the sole, independent predictor of outcomes in multivariate models controlling for relevant covariates.

CONCLUSIONS

There is a need for standardized, multilingual Rx instructions that can be implemented in pharmacy practices to promote safe medication use among LEP patients. The ConcordantRx instructions represent an important step towards achieving this goal.

BACKGROUND

In sub-Saharan Africa, malnutrition and malaria remain major causes of morbidity and mortality in young children. There are conflicting data as to whether malnutrition is associated with an increased or decreased risk of malaria. In addition, data are limited on the potential interaction between HIV infection and the association between malnutrition and the risk of malaria.

METHODS

A cohort of 100 HIV-unexposed, 203 HIV-exposed (HIV negative children born to HIV-infected mothers) and 48 HIV-infected children aged 6 weeks to 1 year were recruited from an area of high malaria transmission intensity in rural Uganda and followed until the age of 2.5 years. All children were provided with insecticide-treated bed nets at enrolment and daily trimethoprim-sulphamethoxazole prophylaxis (TS) was prescribed for HIV-exposed breastfeeding and HIV-infected children. Monthly routine assessments, including measurement of height and weight, were conducted at the study clinic. Nutritional outcomes including stunting (low height-for-age) and underweight (low weight-for-age), classified as mild (mean z-scores between -1 and -2 during follow-up) and moderate-severe (mean z-scores < -2 during follow-up) were considered. Malaria was diagnosed when a child presented with fever and a positive blood smear. The incidence of malaria was compared using negative binomial regression controlling for potential confounders with measures of association expressed as an incidence rate ratio (IRR).

RESULTS

The overall incidence of malaria was 3.64 cases per person year. Mild stunting (IRR = 1.24, 95% CI 1.06-1.46, p = 0.008) and moderate-severe stunting (IRR = 1.24, 95% CI 1.03-1.48, p = 0.02) were associated with a similarly increased incidence of malaria compared to non-stunted children. Being mildly underweight (IRR = 1.09, 95% CI 0.95-1.25, p = 0.24) and moderate-severe underweight (IRR = 1.12, 95% CI 0.86-1.46, p = 0.39) were not associated with a significant difference in the incidence of malaria compared to children who were not underweight. There were no significant interactions between HIV-infected, HIV-exposed children taking TS and the associations between malnutrition and the incidence of malaria.

CONCLUSIONS

Stunting, indicative of chronic malnutrition, was associated with an increased incidence of malaria among a cohort of HIV-infected and -uninfected young children living in an area of high malaria transmission intensity. However, caution should be made when making causal inferences given the observational study design and inability to disentangle the temporal relationship between malnutrition and the incidence of malaria.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00527800.