Danny V. Colombara

Standard Treatment Regimens for Nongonococcal Urethritis Have Similar but Declining Cure Rates: A Randomized Controlled Trial

BACKGROUND Azithromycin or doxycycline is recommended for nongonococcal urethritis (NGU); recent evidence suggests their efficacy has declined. We compared azithromycin and doxycycline in men with NGU, hypothesizing that azithromycin was more effective than doxycycline. METHODS From January 2007 to July 2011, English-speaking males ≥16 years, attending a sexually transmitted diseases clinic in Seattle, Washington, with NGU (visible urethral discharge or ≥5 polymorphonuclear leukocytes per high-power field [PMNs/HPF]) were eligible for this double-blind, parallel-group superiority trial. Participants received active azithromycin (1 g) + placebo doxycycline or active doxycycline (100 mg twice daily for 7 days) + placebo azithromycin. Urine was tested for Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Ureaplasma urealyticum biovar 2 (UU-2), and Trichomonas vaginalis (TV) using nucleic acid amplification tests. Clinical cure (<5 PMNs/HPF with or without urethral symptoms and absence of discharge) and microbiologic cure (negative tests for CT, MG, and/or UU-2) were determined after 3 weeks. RESULTS Of 606 men, 304 were randomized to azithromycin and 302 to doxycycline; CT, MG, TV, and UU-2 were detected in 24%, 13%, 2%, and 23%, respectively. In modified intent-to-treat analyses, 172 of 216 (80%; 95% confidence interval [CI], 74%-85%) receiving azithromycin and 157 of 206 (76%; 95% CI, 70%-82%) receiving doxycycline experienced clinical cure (P = .40). In pathogen-specific analyses, clinical cure did not differ by arm, nor did microbiologic cure differ for CT (86% vs 90%, P = .56), MG (40% vs 30%, P = .41), or UU-2 (75% vs 70%, P = .50). No unexpected adverse events occurred. CONCLUSIONS Clinical and microbiologic cure rates for NGU were somewhat low and there was no significant difference between azithromycin and doxycycline. Mycoplasma genitalium treatment failure was extremely common. Clinical Trials Registration.NCT00358462.

Design, Development and Evaluation of rK28-Based Point-of-Care Tests for Improving Rapid Diagnosis of Visceral Leishmaniasis

Background Visceral leishmaniasis (VL) is diagnosed by microscopic confirmation of the parasite in bone marrow, spleen or lymph node aspirates. These procedures are unsuitable for rapid diagnosis of VL in field settings. The development of rK39-based rapid diagnostic tests (RDT) revolutionized diagnosis of VL by offering high sensitivity and specificity in detecting disease in the Indian subcontinent; however, these tests have been less reliable in the African subcontinent (sensitivity range of 75–85%, specificity of 70–92%). We have addressed limitations of the rK39 with a new synthetic polyprotein, rK28, followed by development and evaluation of two new rK28-based RDT prototype platforms. Methodology/Principal Findings Evaluation of 62 VL-confirmed sera from Sudan provided sensitivities of 96.8% and 93.6% (95% CI = K28: 88.83–99.61%; K39: 84.30–98.21%) and specificities of 96.2% and 92.4% (95% CI = K28: 90.53–98.95%; K39: 85.54–96.65%) for rK28 and rK39, respectively. Of greater interest was the observation that individual VL sera with low rK39 reactivity often had much higher rK28 reactivity. This characteristic of the fusion protein was exploited in the development of rK28 rapid tests, which may prove to be crucial in detecting VL among patients with low rK39 antibody levels. Evaluation of two prototype lateral flow-based rK28 rapid tests on 53 VL patients in Sudan and 73 VL patients in Bangladesh provided promisingly high sensitivities (95.9% [95% CI = 88.46–99.1 in Sudan and 98.1% [95% CI = 89.93–99.95%] in Bangladesh) compared to the rK39 RDT (sensitivities of 86.3% [95% CI = 76.25–93.23%] in Sudan and 88.7% [95% CI = 76.97–95.73%] in Bangladesh). Conclusions/Significance Our study compares the diagnostic accuracy of rK39 and rK28 in detecting active VL cases and our findings indicate that rK28 polyprotein has great potential as a serodiagnostic tool. A new rK28-based RDT will prove to be a valuable asset in simplifying VL disease confirmation at the point-of-care.

The global burden of scabies: a cross-sectional analysis from the Global Burden of Disease Study 2015

Summary Background Numerous population-based studies have documented high prevalence of scabies in overcrowded settings, particularly among children and in tropical regions. We provide an estimate of the global burden of scabies using data from the Global Burden of Disease (GBD) Study 2015. Methods We identified scabies epidemiological data sources from an extensive literature search and hospital insurance data and analysed data sources with a Bayesian meta-regression modelling tool, DisMod-MR 2·1, to yield prevalence estimates. We combined prevalence estimates with a disability weight, measuring disfigurement, itch, and pain caused by scabies, to produce years lived with disability (YLDs). With an assumed zero mortality from scabies, YLDs were equivalent to disability-adjusted life-years (DALYs). We estimated DALYs for 195 countries divided into 21 world regions, in both sexes and 20 age groups, between 1990 and 2015. Findings Scabies was responsible for 0·21% of DALYs from all conditions studied by GBD 2015 worldwide. The world regions of east Asia (age-standardised DALYs 136·32), southeast Asia (134·57), Oceania (120·34), tropical Latin America (99·94), and south Asia (69·41) had the greatest burden of DALYs from scabies. Mean percent change of DALY rate from 1990 to 2015 was less than 8% in all world regions, except North America, which had a 23·9% increase. The five individual countries with greatest scabies burden were Indonesia (age-standardised DALYs 153·86), China (138·25), Timor-Leste (136·67), Vanuatu (131·59), and Fiji (130·91). The largest standard deviations of age-standardised DALYs between the 20 age groups were observed in southeast Asia (60·1), Oceania (58·3), and east Asia (56·5), with the greatest DALY burdens in children, adolescents, and the elderly. Interpretation The burden of scabies is greater in tropical regions, especially in children, adolescents, and elderly people. As a worldwide epidemiological assessment, GBD 2015 provides broad and frequently updated measures of scabies burden in terms of skin effects. These global data might help guide research protocols and prioritisation efforts and focus scabies treatment and control measures. Funding Bill & Melinda Gates Foundation.

Suboptimal adherence to doxycycline and treatment outcomes among men with non-gonococcal urethritis: a prospective cohort study

Objective Doxycycline, one of two recommended therapies for non-gonococcal urethritis (NGU), consists of a 7-day course of therapy (100 mg BID). Since suboptimal adherence may contribute to poor treatment outcomes, we examined the association between self-reported imperfect adherence to doxycycline and clinical and microbiologic failure among men with NGU. Methods Men aged ≥16 years with NGU attending a Seattle, WA, sexually transmitted diseases clinic were enrolled in a double-blind, parallel-group superiority trial from January 2007 to July 2011. Men were randomised to active doxycycline/placebo azithromycin or placebo doxycycline/active azithromycin. Imperfect adherence was defined as missing ≥1 dose in 7 days. Urine was tested for Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), and Ureaplasma urealyticum-biovar 2 (UU-2) using nucleic acid amplification tests. Clinical failure (symptoms and ≥5 PMNs/HPF or discharge) and microbiologic failure (positive tests for CT, MG, and/or UU-2) were determined after 3 weeks. Results 184 men with NGU were randomised to active doxycycline and provided data on adherence. Baseline prevalence of CT, MG and UU-2 was 26%, 13% and 27%, respectively. 28% of men reported imperfect adherence, and this was associated with microbiologic failure among men with CT (aRR=9.33; 95% CI 1.00 to 89.2) and UU-2 (aRR=3.08; 95% CI 1.31 to 7.26) but not MG. Imperfect adherence was not significantly associated with clinical failure overall or for any specific pathogens, but it was more common among imperfectly adherent men with CT (aRR=2.63; 0.93–7.41, p=0.07). Conclusions Adherence may be important for microbiologic cure of select pathogens. Factors other than adherence should be considered for CT-negative men with persistent NGU.

Six-year regression and progression of cervical lesions of different human papillomavirus viral loads in varied histological diagnoses.

Objective This study aims to evaluate human papillomavirus (HPV) viral loads as a biomarker for triage into colposcopy and cervical intraepithelial neoplasia grade 2 (CIN2) therapy to reduce the colposcopy referral rate and CIN2 overtreatment in low-resource settings. Methods In 1999, 1997 women aged 35 to 45 years in Shanxi, China, received 6 cervical screenings with pathological confirmation. In 2005, 1461 histologically normal women, 99 with CIN grade 1 (CIN1), and 30 with CIN2 or worse (CIN2+) were rescreened in a follow-up study. Human papillomavirus was detected by Hybrid Capture 2. Viral load, estimated by the ratio of relative light units to standard positive control (RLU/PC), was categorized into 4 groups: negative (<1.0), low (≥1.0, <10.0), moderate (≥10.0, <100.0), and high (≥100.0). We estimated the cumulative incidence of CIN2+ by viral load subgroups and calculated adjusted hazard ratios for CIN2+ using Cox proportional hazards regression. Results Cumulative incidence of CIN2+ increased with baseline HPV viral loads among normal women and women with CIN1 at baseline (P -trend < 0.001). Repeat moderate-high viral load was associated with the highest risk for CIN2+ (adjusted hazard ratio, 188.8; 95% confidence interval, 41.2–864.1). Raising the ratio of relative light units to standard positive control cutoff from 1.0 to 10.0 for colposcopy greatly reduced the referral rate from 18.1% to 12.9%. It also increased the specificity (84.8% vs 90.4%), the positive predictive value (22.5% vs 28.9%), and the positive likelihood ratio (6.4 vs 8.9), yet with loss of sensitivity by 12% (97.6% vs 85.7%). Among women with CIN2 at baseline, 56% regressed to normal, 24% regressed to CIN1, 4% remained CIN2, and 16% progressed to CIN grade 3 or worse. Conclusions Locales using HPV testing as the primary screening method and lacking high-quality cytology-based screening should consider viral load as an alternative to colposcopy triage for women older than 35 years. Viral loads may also predict CIN2 progression until additional biomarkers become available.

Global disability-adjusted life-year estimates of long-term health burden and undernutrition attributable to diarrhoeal diseases in children younger than 5 years.

Summary Background Diarrhoea is a leading cause of death and illness globally among children younger than 5 years. Mortality and short-term morbidity cause substantial burden of disease but probably underestimate the true effect of diarrhoea on population health. This underestimation is because diarrhoeal diseases can negatively affect early childhood growth, probably through enteric dysfunction and impaired uptake of macronutrients and micronutrients. We attempt to quantify the long-term sequelae associated with childhood growth impairment due to diarrhoea. Methods We used the Global Burden of Diseases, Injuries, and Risk Factors Study framework and leveraged existing estimates of diarrhoea incidence, childhood undernutrition, and infectious disease burden to estimate the effect of diarrhoeal diseases on physical growth, including weight and height, and subsequent disease among children younger than 5 years. The burden of diarrhoea was measured in disability-adjusted life-years (DALYs), a composite metric of mortality and morbidity. We hypothesised that diarrhoea is negatively associated with three common markers of growth: weight-for-age, weight-for-height, and height-for-age Z-scores. On the basis of these undernutrition exposures, we applied a counterfactual approach to quantify the relative risk of infectious disease (subsequent diarrhoea, lower respiratory infection, and measles) and protein energy malnutrition morbidity and mortality per day of diarrhoea and quantified the burden of diarrhoeal disease due to these outcomes caused by undernutrition. Findings Diarrhoea episodes are significantly associated with childhood growth faltering. We found that each day of diarrhoea was associated with height-for-age Z-score (–0·0033 [95% CI −0·0024 to −0·0041]; p=4·43 × 10−14), weight-for-age Z-score (–0·0077 [–0·0058 to −0·0097]; p=3·19 × 10−15), and weight-for-height Z-score (–0·0096 [–0·0067 to −0·0125]; p=7·78 × 10−11). After addition of the DALYs due to the long-term sequelae as a consequence of undernutrition, the burden of diarrhoeal diseases increased by 39·0% (95% uncertainty interval [UI] 33·0–46·6) and was responsible for 55 778 000 DALYs (95% UI 49 125 400–62 396 200) among children younger than 5 years in 2016. Among the 15 652 300 DALYs (95% UI 12 951 300–18 806 100) associated with undernutrition due to diarrhoeal episodes, more than 84·7% are due to increased risk of infectious disease, whereas the remaining 15·3% of long-term DALYs are due to increased prevalence of protein energy malnutrition. The burden of diarrhoea has decreased substantially since 1990, but progress has been greater in long-term (78·7% reduction [95% UI 69·3–85·5]) than in acute (70·4% reduction [95% UI 61·7–76·5]) DALYs. Interpretation Diarrhoea represents an even larger burden of disease than was estimated in the Global Burden of Disease Study. In order to adequately address the burden of its long-term sequelae, a renewed emphasis on controlling the risk of diarrhoea incidence may be required. This renewed effort can help further prevent the potential lifelong cost on child health, growth, and overall potential. Funding Bill & Melinda Gates Foundation.

Risk Factors for Severe Cholera among Children under Five in Rural and Urban Bangladesh, 2000–2008: A Hospital-Based Surveillance Study

Background Children under five bear the largest cholera burden. We therefore sought to identify modifiable risk factors among Bangladeshi children. Methodology/Principal Findings We used multivariate Poisson regression to assess risk factors for severe cholera among diarrheal patients presenting at hospitals in Matlab (rural) and Dhaka (urban), Bangladesh. Risk increased with age. Compared to those under one, rural and urban four-year-olds had adjusted risk ratios (aRR) of 4.17 (95% confidence interval (CI) 2.43–7.15) and 6.32 (95% CI: 4.63–8.63), respectively. Breastfeeding halved the risk in both rural (aRR = 0.49, 95% CI: 0.35–0.67) and urban (aRR = 0.51, 95% CI: 0.41–0.62) settings. Rural children’s risk decreased with maternal education (P-trend: <0.001) and increased among those with a family member with diarrhea in the past week (aRR = 1.61, 95% CI: 1.22–2.14) and those with prior vitamin A supplementation (aRR = 1.65, 95% CI: 1.12–2.43). Urban children whose mothers daily (aRR = 0.41, 95% CI: 0.21–0.79) or occasionally (aRR = 0.55, 95% CI: 0.36–0.84) read a newspaper experienced reduced risk. Urban children from households with incomes between 34–84 USD/month had a 30% increased risk compared to those from households with incomes >84 USD/month. Conclusion/Significance Increasing age, lower socioeconomic status, and lack of breastfeeding are key correlates of increased risk for cholera hospitalization among those under five in rural and urban Bangladesh. In addition, having a family member with diarrhea in the past week was associated with increased risk among rural children. Continued attention should be directed to the promotion of breastfeeding. Further research is needed to elucidate the relationship between maternal education and cholera risk. Renewed research regarding the use of chemoprophylaxis among family members of cholera cases may be warranted in rural endemic settings.

Distribution of Genital Wart Human Papillomavirus Genotypes in China: A Multi-Center Study

Although it is understood that low‐risk human papillomavirus (HPV) genotypes are associated with genital warts, there have been very few published studies reporting the genotype‐specific prevalence of HPV among Chinese population. The aim of the study was to assess the prevalence of HPV genotypes in genital warts across China, and thus to evaluate the potential benefit of a quadrivalent HPV vaccine in this population. The tissue samples of a total of 1,005 genital warts cases were collected from seven geographical regions of China. HPV genotypes were analyzed using the general primer PCR and sequence‐based typing method. Prevalence differences between sexes, geographical regions and age groups were assessed. The overall prevalence of HPV DNA in genital warts patients was 88.7% (891/1,005). Low‐risk genotypes predominated, with a prevalence of 78.1% (785/1,005). The most prevalent genotypes were HPV‐6 (41.3%), HPV‐11 (37.6%) and HPV‐16 (10.4%). Among HPV positive patients, single infections were more frequent (866/891, 97.2%) than co‐infections (25/891, 2.8%). Both the overall prevalence of HPV DNA and that of HPV‐6/‐11/‐16 (positive for any of the three types) decreased with age (P‐trend = 0.010 and P‐trend = 0.025, respectively). The prevalence of HPV‐6/‐11 (positive for either HPV type) and HPV‐16 varied by geographic region (P = 0.003 and P ≤ 0.001, respectively). The prevalence of HPV‐16 in female patients between urban and rural areas showed a marginally significant difference (P = 0.05). In sum, the results provide strong evidence that, in China, the most prevalent HPV genotypes in genital warts are HPV‐6, HPV‐11 and HPV‐16. This indicates that a quadrivalent HPV vaccine may decrease the incidence of genital warts in the future. J Med. Virol. 85:1765–1774, 2013.

The impact of HPV vaccination delays in China: Lessons from HBV control programs

It is well-known that vaccination efforts are often limited by available funds, despite being widely considered a cost-effective health intervention. In contrast, few consider the excess disease burden associated with vaccination delays due to failed health policy and bureaucracy. The history of the hepatitis B virus (HBV) vaccine in China is a case in point.

Breastfeeding Practices among Poor Women in Mesoamerica

BACKGROUND Breastfeeding is an effective intervention to reduce pediatric morbidity and mortality. The prevalence of practices and predictors of breastfeeding among the poor in Mesoamerica has not been well described. OBJECTIVES We estimated the prevalence of ever breastfeeding, early initiation of breastfeeding, exclusive breastfeeding, and breastfeeding between 6 mo and 2 y of age using household survey data for the poorest quintile of families living in 6 Mesoamerican countries. We also assessed the predictors of breastfeeding behaviors to identify factors amenable to policy interventions. METHODS We analyzed data from 12,529 children in Guatemala, Honduras, Mexico (Chiapas State), Nicaragua, Panama, and El Salvador using baseline survey data from the Salud Mesoamérica 2015 Initiative. We created multivariable Poisson regression models with robust variance estimates to calculate adjusted risk ratios (aRRs) and 95% CIs for breastfeeding outcomes and to control for sociodemographic and healthcare-related factors. RESULTS Approximately 97% of women in all countries breastfed their child at least once, and 65.1% (Nicaragua) to 79.0% (Panama) continued to do so between 6 mo and 2 y of age. Breastfeeding in the first hour of life varied by country (P < 0.001), with the highest proportion reported in Panama (89.8%) and the lowest in El Salvador (65.6%). Exclusive breastfeeding also varied by country (P = 0.037), ranging from 44.5% in Panama to 76.8% in Guatemala. For every 20% increase in the proportion of peers who exclusively breastfed, there was an 11% (aRR: 1.11, 95% CI: 1.04, 1.18) increase in the likelihood of exclusive breastfeeding. CONCLUSION Our study revealed significant variation in the prevalence of breastfeeding practices by poor women across countries surveyed by the Salud Mesoamérica 2015 initiative. Future interventions to promote exclusive breastfeeding should consider ways to leverage the role of the community in supporting individual women.