Experimental methods in aquatic respirometry: the importance of mixing devices and accounting for background respiration

In light of an increasing trend in fish biology towards using static respirometry techniques without the inclusion of a mixing mechanism and without accurately accounting for the influence of microbial (background) respiration, this paper quantifies the effect of these approaches on the oxygen consumption rates (ṀO2 ) measured from juvenile barramundi Lates calcarifer (mean ± s.e. mass = 20·31 ± 0·81 g) and adult spiny chromis damselfish Acanthochromis polyacanthus (22·03 ± 2·53 g). Background respiration changed consistently and in a sigmoidal manner over time in the treatment with a mixing device (inline recirculation pump), whereas attempts to measure background respiration in the non-mixed treatment yielded highly variable estimates of ṀO2 that were probably artefacts due to the lack of water movement over the oxygen sensor during measurement periods. This had clear consequences when accounting for background respiration in the calculations of fish ṀO2 . Exclusion of a mixing device caused a significantly lower estimate of ṀO2 in both species and reduced the capacity to detect differences between individuals as well as differences within an individual over time. There was evidence to suggest that the magnitude of these effects was dependent on the spontaneous activity levels of the fish, as the difference between mixed and non-mixed treatments was more pronounced for L. calcarifer (sedentary) than for A. polyacanthus (more spontaneously active). It is clear that respirometry set-ups for sedentary species must contain a mixing device to prevent oxygen stratification inside the respirometer. While more active species may provide a higher level of water mixing during respirometry measurements and theoretically reduce the need for a mixing device, the level of mixing cannot be quantified and may change with diurnal cycles in activity. To ensure consistency across studies without relying on fish activity levels, and to enable accurate assessments of background respiration, it is recommended that all respirometry systems should include an appropriate mixing device.

Measurement and relevance of maximum metabolic rate in fishes

Maximum (aerobic) metabolic rate (MMR) is defined here as the maximum rate of oxygen consumption (M˙O2max ) that a fish can achieve at a given temperature under any ecologically relevant circumstance. Different techniques exist for eliciting MMR of fishes, of which swim-flume respirometry (critical swimming speed tests and burst-swimming protocols) and exhaustive chases are the most common. Available data suggest that the most suitable method for eliciting MMR varies with species and ecotype, and depends on the propensity of the fish to sustain swimming for extended durations as well as its capacity to simultaneously exercise and digest food. MMR varies substantially (>10 fold) between species with different lifestyles (i.e. interspecific variation), and to a lesser extent (<three-fold) between individuals of the same species (i.e. intraspecific variation). MMR often changes allometrically with body size and is modulated by several environmental factors, including temperature and oxygen availability. Due to the significance of MMR in determining aerobic scope, interest in measuring this trait has spread across disciplines in attempts to predict effects of climate change on fish populations. Here, various techniques used to elicit and measure MMR in different fish species with contrasting lifestyles are outlined and the relevance of MMR to the ecology, fitness and climate change resilience of fishes is discussed.

Household food insecurity, maternal nutritional status, and infant feeding practices among HIV-infected Ugandan women receiving combination antiretroviral therapy

Household food insecurity (HHFI) may be a barrier to both optimal maternal nutritional status and infant feeding practices, but few studies have tested this relationship quantitatively, and never among HIV-infected individuals. We therefore described the prevalence of HHFI and explored if it was associated with poorer maternal nutritional status, shorter duration of exclusive breastfeeding (EBF) and fewer animal-source complementary foods. We assessed these outcomes using bivariate and multivariate analyses among 178 HIV-infected pregnant and breastfeeding (BF) women receiving combination antiretroviral therapy in the PROMOTE trial (NCT00993031), a prospective, longitudinal cohort study in Tororo, Uganda. HHFI was common; the prevalence of severe, moderate, and little to no household hunger was 7.3, 39.9, and 52.8 %, respectively. Poor maternal nutritional status was common and women in households experiencing moderate to severe household hunger (MSHH) had statistically significantly lower body mass index (BMIs) at enrollment (21.3 vs. 22.5, p < 0.01) and prior to delivery (22.6 vs. 23.8, p < 0.01). BMI across time during pregnancy, but not gestational weight gain, was significantly lower for MSHH [adjusted beta (95 % CI) -0.79 (-1.56, -0.02), p = 0.04; -2.06 (-4.31, 0.19), p = 0.07], respectively. The prevalence (95 % CI) of EBF at 6 months was 67.2 % (59.7-73.5 %), and the proportion of women BF at 12 months was 80.4 % (73.3-85.7 %). MSHH was not associated with prevalence of EBF at 6 months or BF at 12 months. However, among those women still EBF at 4 months (81.4 % of population), those experiencing MSHH were significantly more likely to cease EBF between 4 and 6 months (aHR 2.38, 95 % CI 1.02-5.58). The prevalence of HHFI, maternal malnutrition, and suboptimal infant feeding practices are high and the causal relationships among these phenomena must be further explored.

Hair concentrations of antiretrovirals predict viral suppression in HIV-infected pregnant and breastfeeding Ugandan women

OBJECTIVE

Hair concentrations are a noninvasive measure of cumulative antiretroviral exposure and the strongest predictor of viral suppression in large cohorts of nonpregnant patients. We examined hair concentrations of antiretrovirals in relation to virologic outcomes in pregnant and breastfeeding women for the first time.

DESIGN AND METHODS

The Prevention of Malaria and HIV Disease in Tororo trial (NCT00993031) enrolled HIV-infected pregnant Ugandan women at 12-28 weeks gestation who were randomized to lopinavir or efavirenz-based antiretroviral therapy (ART). Small hair samples were collected at 30-34 weeks gestation and 10-25 weeks postpartum. Efavirenz and lopinavir hair concentrations were measured via liquid chromatography/tandem mass spectrometry. Multivariate logistic regression models examined predictors of viral suppression (HIV-1 RNA ≤400 copies/ml) at delivery and 24 weeks postpartum.

RESULTS

Among 325 women, median CD4 cell count was 366 cells/μl (interquartile range 270-488) at ART initiation. Mean self-reported 3-day adherence was greater than 97% in each arm. Viral suppression was achieved by 98.0% (efavirenz) and 87.4% (lopinavir) at delivery. At 24 weeks postpartum, 92.5% (efavirenz) and 90.6% (lopinavir) achieved viral suppression; 88% of women were breastfeeding. In multivariate models including self-reported adherence and pretreatment HIV-1 RNA, antiretroviral hair concentrations were the strongest predictor of viral suppression at delivery [efavirenz: adjusted odds ratio (aOR) 1.86 per doubling in concentration, 95% confidence interval (CI) 1.14-3.1, P = 0.013; lopinavir: aOR 1.90, 95% CI 1.33-2.7, P = 0.0004] and 24 weeks postpartum (efavirenz: aOR 1.81, 95% CI 1.22-2.7, P = 0.003; lopinavir: aOR 1.53, 95% CI 1.05-2.2, P = 0.026).

CONCLUSION

Antiretroviral hair concentrations represent an innovative tool that strongly predicts viral suppression among HIV-infected childbearing women during the critical periods of delivery and breastfeeding.

Poor housing construction associated with increased malaria incidence in a cohort of young Ugandan children

Despite the use of accepted interventions to combat malaria, such as insecticide-treated bed nets and artemisinin-based combination therapy, malaria remains a leading cause of morbidity and mortality in Uganda. We investigated associations between household factors and malaria incidence in a cohort of children living in a highly endemic region of Uganda. Living in a modern house, defined as the use of non-earth floors, non-thatched roofs, and non-mud walls, was associated with approximately half malaria incidence compared with living in a traditional home (incidence rate ratio [IRR] = 0.54, P = 0.001). Other factors found to be associated with a lower incidence of malaria included living in town versus rural setting; sleeping in a room with openings to the outside (windows, eaves, and airbricks); and having an older and more educated primary caregiver. This study adds to the growing body of evidence that improved house construction may be associated with a lower risk of malaria.

Protective efficacy and safety of three antimalarial regimens for the prevention of malaria in young Ugandan children: a randomized controlled trial

BACKGROUND

Chemoprevention offers a promising strategy for prevention of malaria in African children. However, the optimal chemoprevention drug and dosing strategy is unclear in areas of year-round transmission and resistance to many antimalarial drugs. To compare three available regimens, we conducted an open-label randomized controlled trial of chemoprevention in Ugandan children.

METHODS AND FINDINGS

This study was conducted between June 28, 2010, and September 25, 2013. 400 infants were enrolled and 393 randomized at 6 mo of age to no chemoprevention, monthly sulfadoxine-pyrimethamine (SP), daily trimethoprim-sulfamethoxazole (TS), or monthly dihydroartemisinin-piperaquine (DP). Study drugs were administered at home without supervision. Piperaquine (PQ) levels were used as a measure of compliance in the DP arm. Participants were given insecticide-treated bednets, and caregivers were encouraged to bring their child to a study clinic whenever they were ill. Chemoprevention was stopped at 24 mo of age, and participants followed-up an additional year. Primary outcome was the incidence of malaria during the intervention period. During the intervention, the incidence of malaria in the no chemoprevention arm was 6.95 episodes per person-year at risk. Protective efficacy was 58% (95% CI, 45%-67%, p<0.001) for DP, 28% (95% CI, 7%-44%, p = 0.01) for TS, and 7% for SP (95% CI, -19% to 28%, p = 0.57). PQ levels were below the detection limit 52% of the time when malaria was diagnosed in the DP arm, suggesting non-adherence. There were no differences between the study arms in the incidence of serious adverse events during the intervention and the incidence of malaria during the 1-y period after the intervention was stopped.

CONCLUSIONS

For preventing malaria in children living in an area of high transmission intensity, monthly DP was the most efficacious and safe, although adherence may pose a problem. Monthly SP and daily TS may not be appropriate in areas with high transmission intensity and frequent resistance to antifolates.

TRIAL REGISTRATION

www.ClinicalTrials.gov NCT00948896 Please see later in the article for the Editors' Summary.

Lopinavir/ritonavir-based antiretroviral treatment (ART) versus efavirenz-based ART for the prevention of malaria among HIV-infected pregnant women

BACKGROUND

Human immunodeficiency virus (HIV)-infected pregnant women are at increased risk of malaria and its complications. In vitro and in vivo data suggest that the HIV protease inhibitors lopinavir/ritonavir may have potent antimalarial activity. We sought to evaluate whether lopinavir/ritonavir-based antiretroviral therapy (ART) reduced the risk of placental malaria.

METHODS

HIV-infected, ART-naive pregnant women were enrolled between gestational weeks 12 and 28 and randomly assigned to receive lopinavir/ritonavir-based or efavirenz-based ART. Women received daily trimethoprim-sulfamethoxazole prophylaxis and insecticide-treated bed nets at enrollment and were followed up to 1 year after delivery. The primary outcome was placental malaria, defined by the detection of malaria parasites, using microscopy or polymerase chain reaction (PCR) analysis of placental blood specimens. Secondary outcomes included placental malaria, defined by histopathologic results; adverse birth outcomes; incidence of malaria; and prevalence of asymptomatic parasitemia. Analyses were done using an intention-to-treat approach.

RESULTS

Of 389 subjects randomly assigned to a treatment group, 377 were followed through to delivery. There was no significant difference in the risk of placental malaria, as defined by thick smear or PCR findings, between the lopinavir/ritonavir-based and efavirenz-based ART arms (7.4% vs 9.8%; P = .45). Similarly, there were no differences in secondary outcomes between the 2 treatment arms.

CONCLUSIONS

Lopinavir/ritonavir-based ART did not reduce the risk of placental or maternal malaria or improve birth outcomes, compared with efavirenz-based ART.

CLINICAL TRIALS REGISTRATION

NCT00993031.

Cardiac tamponade: new technology masking an old nemesis

A 16-year-old male patient underwent bilateral pulmonary embolectomy complicated by reperfusion injury and acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation support using a bicaval double-lumen catheter. A unique hemodynamic profile developed consistent with tamponade but without an associated decrease in venovenous extracorporeal membrane oxygenation pump flow, improved venovenous extracorporeal membrane oxygenation circuit preload, and decreased recirculation. The use of newer bicaval double-lumen catheters can result in old problems presenting in new ways and require clinicians to be ever vigilant.

Artemisinin-based combination therapies are efficacious and safe for treatment of uncomplicated malaria in HIV-infected Ugandan children

BACKGROUND

Artemisinin-based combination therapies (ACTs) are highly efficacious and safe, but data from human immunodeficiency virus (HIV)-infected children concurrently receiving antiretroviral therapy (ART) and ACTs are limited.

METHODS

We evaluated 28-day outcomes following malaria treatment with artemether-lumefantrine (AL) or dihydroartemisinin-piperaquine (DP) in 2 cohorts of HIV-infected Ugandan children taking various ART regimens. In one cohort, children <6 years of age were randomized to lopinavir/ritonavir (LPV/r) or nonnucleoside reverse transcriptase inhibitor-based ART and treated with AL for uncomplicated malaria. In another cohort, children <12 months of age were started on nevirapine-based ART if they were eligible, and randomized to AL or DP for the treatment of their first and all subsequent uncomplicated malaria episodes.

RESULTS

There were 773 and 165 treatments for malaria with AL and DP, respectively. Initial response to therapy was excellent, with 99% clearance of parasites and <1% risk of repeat therapy within 3 days. Recurrent parasitemia within 28 days was common following AL treatment. The risk of recurrent parasitemia was significantly lower among children taking LPV/r-based ART compared with children taking nevirapine-based ART following AL treatment (15.3% vs 35.5%, P = .009), and those treated with DP compared with AL (8.6% vs 36.2%, P < .001). Both ACT regimens were safe and well tolerated.

CONCLUSIONS

Treatment of uncomplicated malaria with AL or DP was efficacious and safe in HIV-infected children taking ART. However, there was a high risk of recurrent parasitemia following AL treatment, which was significantly lower in children taking LPV/r-based ART compared with nevirapine-based ART.

Changes in population HIV RNA levels in Mbarara, Uganda, during scale-up of HIV antiretroviral therapy access

OBJECTIVE

In a rural Ugandan community scaling up antiretroviral therapy (ART), we sought to determine if population-based HIV RNA levels [population viral load (VL)] decreased from 2011 to 2012.

DESIGN

Serial cross-sectional analyses (May 2011 and May 2012) of a defined study community of 6300 persons in a district with HIV prevalence of 8%.

METHODS

We measured HIV-1 RNA (VL) levels on all individuals testing positive for HIV during a 5-day high-throughput multidisease community health campaign in May 2012 that recruited two-thirds of the population. We aggregated individual-level VL results into population VL metrics including the proportion of individuals with an undetectable VL and compared these VL metrics to those we previously reported for this geographic region in 2011.

RESULTS

In 2012, 223 of 2179 adults were HIV-seropositive adults (10%). Overall, among 208 of 223 HIV-seropositive adults in whom VL was tested, 53% had an undetectable VL [95% confidence interval (CI): 46 to 60], up from 37% (95% CI: 30 to 45; P = 0.02) in 2011. Seven (3%) individuals had a VL of >100,000 copies/mL in 2012, down from 21 (13%) in 2011 (P = 0.0007). Mean log (VL) (geometric mean) was 3.18 log (95% CI: 3.06 to 3.29 log) in 2012, down from 3.62 log (95% CI: 3.46 to 3.78 log) in 2011 (P < 0.0001). Similar reductions in population VL were seen among men and women.

CONCLUSIONS

Reductions in population VL metrics and a substantial increase in the proportion of persons with an undetectable VL were observed in a rural Ugandan community from 2011 to 2012. These findings from a resource-limited setting experiencing rapid ART scale-up may reflect a population-level effectiveness of expanding ART access.

Evaluating linkage to care for hypertension after community-based screening in rural Uganda

OBJECTIVES

To determine the frequency and predictors of hypertension linkage to care after implementation of a linkage intervention in rural Uganda.

METHODS

During a multidisease screening campaign for HIV, diabetes and hypertension in rural Uganda, hypertensive adults received education, appointment to a local health facility and travel voucher. We measured frequency and predictors of linkage to care, defined as visiting any health facility for hypertension management within 6 months. Predictors of linkage to care were calculated using collaborative-targeted maximum likelihood estimation (C-TMLE). Participants not linking were interviewed using a standardised instrument to determine barriers to care.

RESULTS

Over 5 days, 2252 adults were screened for hypertension and 214 hypertensive adults received a linkage intervention for further management. Of these, 178 (83%) linked to care within 6 months (median = 22 days). Independent predictors of successful linkage included older age, female gender, higher education, manual employment, tobacco use, alcohol consumption, hypertension family history and referral to local vs. regional health centre. Barriers for patients who did not see care included expensive transport (59%) and feeling well (59%).

CONCLUSIONS

A community health campaign that offered hypertension screening, education, referral appointment and travel voucher achieved excellent linkage to care (83%). Young adults, men and persons with low levels of formal education were among those least likely to seek care.

Epidemiology and awareness of hypertension in a rural Ugandan community: a cross-sectional study

BACKGROUND

Hypertension is one of the largest causes of preventable morbidity and mortality worldwide. There are few population-based studies on hypertension epidemiology to guide public health strategies in sub-Saharan Africa. Using a community-based strategy that integrated screening for HIV and non-communicable diseases, we determined the prevalence, awareness, treatment rates, and sociodemographic factors associated with hypertension in rural Uganda.

METHODS

A household census was performed to enumerate the population in Kakyerere parish in Mbarara district, Uganda. A multi-disease community-based screening campaign for hypertension, diabetes, and HIV was then conducted. During the campaign, all adults received a blood pressure (BP) measurement and completed a survey examining sociodemographic factors. Hypertension was defined as elevated BP (≥ 140/≥ 90 mmHg) on the lowest of three BP measurements or current use of antihypertensives. Prevalence was calculated and standardized to age distribution. Sociodemographic factors associated with hypertension were evaluated using a log-link Poisson regression model with robust standard errors.

RESULTS

Community participation in the screening campaign was 65%, including 1245 women and 1007 men. The prevalence of hypertension was 14.6%; awareness of diagnosis (38.1%) and current receipt of treatment (20.6%) were both low. Age-standardized to the WHO world standard population, hypertension prevalence was 19.8%, which is comparable to 21.6% in the US and 18.4% in the UK. Sociodemographic factors associated with hypertension included increasing age, male gender, overweight, obesity, diabetes, alcohol consumption, and family history. Prevalence of modifiable factors was high: 28.3% women were overweight/obese and 24.1% men consumed ≥ 10 alcoholic drinks per month.

CONCLUSIONS

We found a substantial burden of hypertension in rural Uganda. Awareness and treatment of hypertension is low in this region. Enhanced community-based education and prevention efforts tailored to addressing modifiable factors are needed.

Neonatal mortality in HIV-exposed infants born to women receiving combination antiretroviral therapy in Rural Uganda

As human immunodeficiency virus (HIV)-infected women gain access to combination antiretroviral therapy throughout sub-Saharan Africa, a growing number of infants are being born HIV-exposed but uninfected. Data about neonatal mortality and the impact of premature delivery, in this population are limited. We describe the 28-day mortality outcomes in a cohort of HIV-exposed infants who had ultrasound-confirmed gestational age in rural Uganda. There were 13 deaths among 351 infants, including 9 deaths in the perinatal period. Premature delivery was a strong predictor of mortality. The prevention of HIV transmission to infants is now possible in rural low-resource settings but the frequency of neonatal death among HIV-exposed infants remains extremely high, calling for new comprehensive interventions to reduce mortality in this growing population.

Blood lactate loads of redthroat emperor Lethrinus miniatus associated with angling stress and exhaustive exercise

Baseline, post-angling and maximum attainable blood lactate concentrations were measured for the fishery species redthroat emperor Lethrinus miniatus to gain insight into the condition of fish released following c. 30 s angling and <45 s air exposure. Mean ± S.D. baseline blood lactate was 1·5 ± 0·6 mmol l⁻¹, which increased and plateaued around 6 mmol l⁻¹ at 15-30 min post-angling. These values were significantly lower than those obtained from fish maximally exhausted with a prolonged chase and air exposure protocol following capture (10·9 ± 1·8 mmol l⁻¹), suggesting that L. miniatus is not maximally exhausted during standard angling practices.

Acceptability and feasibility of serial HIV antibody testing during pregnancy/postpartum and male partner testing in Tororo, Uganda

Our objective was to determine whether serial HIV testing during pregnancy and the postpartum period as well as male partner testing are acceptable and feasible in Tororo, Uganda. This was a prospective study of pregnant women at the Tororo District Hospital (TDH) Antenatal Clinic. Patients presenting for routine antenatal care were asked to participate in a serial HIV testing integrated into standard antenatal and postpartum/child immunization visits, and to invite their male partners for HIV testing. Serial testing was defined as ≥2 tests during pregnancy and ≥2 tests within 24 weeks postpartum. Of the 214 enrolled women, 80 (37%) completed serial testing, 176 (82%) had ≥2 tests, and 147 (69%) had ≥3 tests during the study period. One hundred eighty-two women (85%) accepted male partner testing, but only 19 men (10%) participated. One woman seroconverted during the study, for a cumulative HIV incidence of 0.5% (1/214). In multivariable logistic regression analysis, longer distance between home and clinic (aOR 0.87 [95% CI 0.79-0.97]) and not knowing household income (aOR 0.30 [95% CI 0.11-0.84]) were predictive of not completing serial testing. Higher level of education was associated with completing serial testing (linear trend p value = 0.05). In conclusion, partial serial HIV testing was highly acceptable and feasible, but completion of serial testing and male partner testing had poor uptake.

High retention in care among HIV-infected patients entering care with CD4 levels >350 cells/μL under routine program conditions in Uganda

BACKGROUND

In Africa, human immunodeficiency virus (HIV)-infected patients who present to care with CD4 levels >350 cells/µL (ie, current antiretroviral treatment thresholds) are often thought to be poorly retained in care, but most estimates do not account for outcomes among patients lost to follow-up.

METHODS

We evaluated HIV-infected adults who had made a visit in the last 2.5 years in a program in Uganda. We identified a random sample of patients lost to follow-up (9 months without a visit). Ascertainers sought patients in the community in this sample and outcomes were incorporated into revised survival estimates of mortality and retention for the clinic population using a probability weight.

RESULTS

Of 6473 patients, (29% male, median age 29 years, median CD4 count 550 cells/µL), 1294 (20%) became lost to follow-up over 2.5 years. Two hundred seven (16%) randomly selected lost patients were sought, and in 175 (85%) vital status was ascertained. In 19 of 175 (11%), the patient had died. Of the 156 (89%) alive, 74 (47%) were interviewed in person, and 38 of 74 (51%) reported HIV care elsewhere, whereas 36 of 74 (49%) were not in care. Application of weights derived from sampling found that at 2.5 years, retention among patients who enrolled with CD4 levels >350 cells/µL was 88.2% and mortality was 2.5%. Lower income, unemployment, and rural residence were associated with failure to be retained.

CONCLUSIONS

Retention in patients entering care with high CD4 counts under routine program conditions in Africa is high in a Ugandan care program and may be systematically underestimated in many other settings.

Improved employment and education outcomes in households of HIV-infected adults with high CD4 cell counts: evidence from a community health campaign in Uganda

BACKGROUND

There is limited evidence on the association between socioeconomic outcomes and CD4 counts in populations that include HIV-infected adults who have high CD4 counts or have not been diagnosed. We examined this association among adults in a rural Ugandan parish.

METHODS

A community health campaign offering diagnostic and treatment services for HIV and other diseases was conducted with Ministry of Health support. Data on campaign participants' education and employment were collected and a detailed household socioeconomic survey was conducted among a subset of participants. Regression analyses were used to assess relationships between CD4 count and employment and education outcomes.

RESULTS

A total of 2323 adults (74% of the community) participated in the campaign; 179 of 2282 (7.8%) tested HIV-positive and 46% were newly diagnosed. Among HIV-infected adults not on antiretroviral therapy (ART), those with CD4 at least 500 worked 6.9 more days/month (P < 0.01; 39% more) and 2.5 more h per day (P < 0.05, 44% more) than those with CD4 less than 200. These effects were not significantly different from the effects for those with CD4 350-499. Children aged 6-11 years in households of adults with CD4 at least 350 did not have significantly different school enrollment rates than children in households of adults with CD4 less than 350, but differences were larger among children aged 12-18 years.

CONCLUSION

Outcomes of HIV-infected adults with CD4 at least 350 were better than those of adults with CD4 less than 200 and resembled those of HIV-uninfected adults. The results suggest that early ART initiation may generate economic benefits by preventing a decline in socioeconomic status, but further research is needed to determine the CD4 threshold at which these benefits would be largest.

Prevalence of asymptomatic parasitemia and gametocytemia among HIV-infected Ugandan children randomized to receive different antiretroviral therapies

In a recent randomized controlled trial, the use of protease inhibitor (PI)-based antiretroviral therapy (ART) was associated with a significantly lower incidence of malaria compared with non-nucleoside reverse transcriptase inhibitor-based ART in a cohort of human immunodeficiency virus-infected Ugandan children living in an area of high malaria transmission intensity. In this report, we compared the prevalence of asymptomatic parasitemia and gametocytemia using data from the same cohort. The prevalence of asymptomatic parasitemia did not differ between the two ART treatment arms. The PI-based arm was associated with a lower risk of gametocytemia at the time of diagnosis of malaria (6.6% versus 14.5%, P = 0.03) and during the 28 days after malaria diagnosis (3.4% versus 6.5%, P = 0.04). Thus, in addition to decreasing the incidence of malaria, the use of PI-based ART may lower transmission, as a result of a decrease in gametocytemia, in areas of high malaria transmission intensity.

Assessment of population-based HIV RNA levels in a rural east African setting using a fingerprick-based blood collection method

BACKGROUND

Population-based human immunodeficiency virus type 1 (HIV-1) RNA levels (viral load [VL]) are proposed metrics for antiretroviral therapy (ART) program effectiveness. We estimated population-based HIV RNA levels using a fingerprick-based approach in a rural Ugandan community implementing rapid ART scale-up.

METHODS

A fingerprick-based HIV RNA measurement technique was validated against standard phlebotomy. This technique was deployed during a 5-day community-wide health campaign in a 6300-person community. Assessments included rapid HIV antibody testing, VL, and CD4+ T-cell count via fingerprick. We estimated population HIV RNA levels and the prevalence of undetectable RNA, assessed predictors of VL via linear regression, and mapped RNA levels within community geographic units.

RESULTS

During the community-wide health campaign, 179 of 2282 adults (7.8%) and 10 of 1826 children (0.5%) tested seropositive for HIV. Fingerprick VL was determined in 174 of 189 HIV-positive persons (92%). The mean log(VL) was 3.67 log (95% confidence interval [CI], 3.50-3.83 log copies/mL), median VL was 2720 copies/mL (interquartile range, <486-38 120 copies/mL), and arithmetic mean VL was 64 064 copies/mL. Overall, 64 of 174 of individuals had undetectable RNA (37% [95% CI, 30%-44%]), 24% had VL 486-10 000; 25% had VL 10 001-100 000; and 15% had VL>100 000 copies/mL. Among participants taking ART, 83% had undetectable VL.

CONCLUSIONS

We developed and implemented a fingerprick VL testing method and provide the first report of population HIV RNA levels in Africa. In a rural Ugandan community experiencing ART scale-up, we found evidence of population-level ART effectiveness, but found a substantial population to be viremic, in need of ART, and at risk for transmission.

Antiretroviral agents and prevention of malaria in HIV-infected Ugandan children

BACKGROUND

Human immunodeficiency virus (HIV) protease inhibitors show activity against Plasmodium falciparum in vitro. We hypothesized that the incidence of malaria in HIV-infected children would be lower among children receiving lopinavir-ritonavir-based antiretroviral therapy (ART) than among those receiving nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based ART.

METHODS

We conducted an open-label trial in which HIV-infected children 2 months to 5 years of age who were eligible for ART or were currently receiving NNRTI-based ART were randomly assigned to either lopinavir-ritonavir-based ART or NNRTI-based ART and were followed for 6 months to 2 years. Cases of uncomplicated malaria were treated with artemether-lumefantrine. The primary end point was the incidence of malaria.

RESULTS

We enrolled 176 children, of whom 170 received the study regimen: 86 received NNRTI-based ART, and 84 lopinavir-ritonavir-based ART. The incidence of malaria was lower among children receiving the lopinavir-ritonavir-based regimen than among those receiving the NNRTI-based regimen (1.32 vs. 2.25 episodes per person-year; incidence-rate ratio, 0.59; 95% confidence interval [CI], 0.36 to 0.97; P=0.04), as was the risk of a recurrence of malaria after treatment with artemether-lumefantrine (28.1% vs. 54.2%; hazard ratio, 0.41; 95% CI, 0.22 to 0.76; P=0.004). The median lumefantrine level on day 7 after treatment for malaria was significantly higher in the lopinavir-ritonavir group than in the NNRTI group. In the lopinavir-ritonavir group, lumefantrine levels exceeding 300 ng per milliliter on day 7 were associated with a reduction of more than 85% in the 63-day risk of recurrent malaria. A greater number of serious adverse events occurred in the lopinavir-ritonavir group than in the NNRTI group (5.6% vs. 2.3%, P=0.16). Pruritus occurred significantly more frequently in the lopinavir-ritonavir group, and elevated alanine aminotransferase levels significantly more frequently in the NNRTI group.

CONCLUSIONS

Lopinavir-ritonavir-based ART as compared with NNRTI-based ART reduced the incidence of malaria by 41%, with the lower incidence attributable largely to a significant reduction in the recurrence of malaria after treatment with artemether-lumefantrine. Lopinavir-ritonavir-based ART was accompanied by an increase in serious adverse events. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development; ClinicalTrials.gov number, NCT00978068.).

Leveraging rapid community-based HIV testing campaigns for non-communicable diseases in rural Uganda

BACKGROUND

The high burden of undiagnosed HIV in sub-Saharan Africa limits treatment and prevention efforts. Community-based HIV testing campaigns can address this challenge and provide an untapped opportunity to identify non-communicable diseases (NCDs). We tested the feasibility and diagnostic yield of integrating NCD and communicable diseases into a rapid HIV testing and referral campaign for all residents of a rural Ugandan parish.

METHODS

A five-day, multi-disease campaign, offering diagnostic, preventive, treatment and referral services, was performed in May 2011. Services included point-of-care screening for HIV, malaria, TB, hypertension and diabetes. Finger-prick diagnostics eliminated the need for phlebotomy. HIV-infected adults met clinic staff and peer counselors on-site; those with CD4 ≤ 100/µL underwent intensive counseling and rapid referral for antiretroviral therapy (ART). Community participation, case-finding yield, and linkage to care three months post-campaign were analyzed.

RESULTS

Of 6,300 residents, 2,323/3,150 (74%) adults and 2,020/3,150 (69%) children participated. An estimated 95% and 52% of adult female and male residents participated respectively. Adult HIV prevalence was 7.8%, with 46% of HIV-infected adults newly diagnosed. Thirty-nine percent of new HIV diagnoses linked to care. In a pilot subgroup with CD4 ≤ 100, 83% linked and started ART within 10 days. Malaria was identified in 10% of children, and hypertension and diabetes in 28% and 3.5% of adults screened, respectively. Sixty-five percent of hypertensives and 23% of diabetics were new diagnoses, of which 43% and 61% linked to care, respectively. Screening identified suspected TB in 87% of HIV-infected and 19% of HIV-uninfected adults; 52% percent of HIV-uninfected TB suspects linked to care.

CONCLUSIONS

In an integrated campaign engaging 74% of adult residents, we identified a high burden of undiagnosed HIV, hypertension and diabetes. Improving male attendance and optimizing linkage to care require new approaches. The campaign demonstrates the feasibility of integrating hypertension, diabetes and communicable diseases into HIV initiatives.

The efficacy of field techniques for obtaining and storing blood samples from fishes

Prompted by the dramatic increase in the use of blood analyses in fisheries research and monitoring, this study investigated the efficacy of common field techniques for sampling and storing blood from fishes. Three questions were addressed: (1) Do blood samples taken via rapid caudal puncture (the 'grab-and-stab' technique) yield similar results for live v. sacrificed groups of fishes? (2) Do rapidly obtained caudal blood samples accurately represent blood properties of fishes prior to capture? (3) Does storage of whole blood in an ice slurry for a working day (8·5 h) modify the properties of the plasma? It was shown that haematocrit, plasma ions, metabolites, stress hormones and sex hormones of caudal blood samples were statistically similar when taken from live v. recently sacrificed groups of adult coho salmon Oncorhynchus kisutch. Moreover, this study confirmed by using paired blood samples from cannulated O. kisutch that blood acquired through the caudal puncture technique (mean ±s.e. 142 ± 26 s after capture) was representative of fish prior to capture. Long-term (8·5 h) cold storage of sockeye salmon Oncorhynchus nerka whole blood caused significant decreases in plasma potassium and chloride, and a significant increase in plasma glucose. Previous research has suggested that these changes largely result from net movements of ions and molecules between the plasma and erythrocytes, movements that can occur within minutes of storage. Thus, blood samples from fishes should be centrifuged as quickly as practicable in the field for separation of plasma and erythrocytes to prevent potentially misleading data.

Physiological responses of free-swimming adult coho salmon to simulated predator and fisheries encounters

The responses of free-swimming adult coho salmon (Oncorhynchus kisutch) to simulated predator and fisheries encounters were assessed by monitoring heart rate (f(H)) with implanted data loggers and periodically taking caudal blood samples. A 10- or 30-min corralling treatment was conducted to simulate conspecifics being cornered by a predator or corralled by fisheries gear without physical contact. Corralling rapidly doubled f(H) from ∼31 beats min(-1) to a maximum of ∼60 beats min(-1), regardless of the duration of the corralling. However, recovery of f(H) to precorralling levels was significantly faster after the 10-min corralling (7.6 h) than after the 30-min corralling (11.5 h). An exhaustive-exercise treatment (chasing for 3 min, with physical contact) to simulate a predator chasing a fish to exhaustion or a fish becoming exhausted after encountering fisheries gear resulted in increased f(H) (to 60 beats min(-1)), plasma lactate, glucose, sodium, osmolality, and cortisol (males only) and a significant decrease in mean corpuscular hemoglobin concentration. Recovery of f(H) and most blood variables was complete about 16 h after exhaustive exercise and handling. The results illustrate a clear relationship between the intensity of exercise and the duration required for recovery of f(H). Changes in f(H) were significantly correlated with those in plasma lactate, chloride, and sodium at 1 h after the exercise treatment protocols. Thus, measurements of f(H) may provide an accurate indication of the general physiological response of salmonids to exhaustive exercise in the natural environment.

Use of an automated circuit for isolated limb infusion for malignancy

BACKGROUND

Isolated limb infusion (ILI) for recurrent or in-transit melanoma is an accepted technique that allows high-dose chemotherapy to be delivered to an extremity with minimal systemic toxicity. Current infusion systems have relied on manual delivery of drugs and circulation of blood during the treatment. Herein, we document our initial results with an automated circuit for ILI as an alternative to the manual technique.

METHODS

Patients undergoing ILI with an automated circuit for recurrent or advanced malignancy were identified. ILI was performed utilizing a Sarns 8000 roller pump attached to a Cobe 4:1 cardioplegia set with heat exchanger with a total priming volume of 80 ml. Melphalan (7.5 mg/L) and Dactinomycin (75 μg/L) doses which were corrected for ideal body weight were delivered via the infusion circuit after limb temperature reached 38 °C.

RESULTS

Fourteen lower extremity infusion procedures were performed in 10 patients. Successful infusion procedures were completed in all patients using the automated circuit. Constant flow rates of 50-70 cc/minute were achievable with the automated circuit. Acute toxicity and clinical results were similar to that reported with manual delivery systems.

CONCLUSION

ILI for advanced malignancy utilizing an automated circuit is feasible and safe. This automated system offers a safe and reliable alternative to the manual infusion technique.

Impact of the method of G6PD deficiency assessment on genetic association studies of malaria susceptibility

Background

Clinical association studies have yielded varied results regarding the impact of glucose-6-phosphate dehydrogenase (G6PD) deficiency upon susceptibility to malaria. Analyses have been complicated by varied methods used to diagnose G6PD deficiency.

Methodology/Prinicipal Findings

We compared the association between uncomplicated malaria incidence and G6PD deficiency in a cohort of 601 Ugandan children using two different diagnostic methods, enzyme activity and G6PD genotype (G202A, the predominant East African allele). Although roughly the same percentage of males were identified as deficient using enzyme activity (12%) and genotype (14%), nearly 30% of males who were enzymatically deficient were wild-type at G202A. The number of deficient females was three-fold higher with assessment by genotype (21%) compared to enzyme activity (7%). Heterozygous females accounted for the majority (46/54) of children with a mutant genotype but normal enzyme activity. G6PD deficiency, as determined by G6PD enzyme activity, conferred a 52% (relative risk [RR] 0.48, 95% CI 0.31–0.75) reduced risk of uncomplicated malaria in females. In contrast, when G6PD deficiency was defined based on genotype, the protective association for females was no longer seen (RR = 0.99, 95% CI 0.70–1.39). Notably, restricting the analysis to those females who were both genotypically and enzymatically deficient, the association of deficiency and protection from uncomplicated malaria was again demonstrated in females, but not in males (RR = 0.57, 95% CI 0.37–0.88 for females).

Conclusions/Significance

This study underscores the impact that the method of identifying G6PD deficient individuals has upon association studies of G6PD deficiency and uncomplicated malaria. We found that G6PD-deficient females were significantly protected against uncomplicated malaria, but this protection was only seen when G6PD deficiency is described using enzyme activity. These observations may help to explain the discrepancy in some published association studies involving G6PD deficiency and uncomplicated malaria.