Zika virus RNA and IgM persistence in blood compartments and body fluids: a prospective observational study.

BACKGROUND: Characterisation of the dynamics of Zika virus persistence following acute infection is needed to inform blood donor and diagnostic testing policies and understand the natural history of Zika virus infection. We aimed to characterise the natural history, persistence, and clinical outcomes of Zika virus infection through a prospective study in initially asymptomatic Zika virus RNA-positive blood donors. METHODS: Zika virus-infected blood donors identified through Zika virus nucleic acid amplification test (NAAT) screening at three blood collection organisations in the USA were enrolled into a 1-year follow-up study, with blood and body fluid samples and detailed symptom data collected at up to seven visits. All samples were tested for Zika virus RNA by real-time PCR (rtPCR); follow-up plasma, whole blood, and urine were also tested by replicate NAAT. Plasma was tested for flavivirus-specific IgM and IgG by ELISA. Zika virus RNA persistence for each assay or sample type and plasma antibody persistence from estimated date of plasma NAAT-detectable infection were calculated from follow-up data using survival statistical methods. FINDINGS: Between July 6, 2016 and March 7, 2017, we enrolled 53 participants. From the estimated date of plasma NAAT-detectable infection, Zika virus RNA was detectable in plasma for 9·9 days (95% CI 8·1-12·0), in red blood cells for 95·4 days (62·8-129·1), and in whole blood for 73·5 days (39·8-107·5). Replicate NAATs (one or more of eight replicates positive) extended detection of Zika virus RNA in plasma to 34·8 days (19·9-56·2) and in whole blood (at least one of two tests positive) to 104·8 days (76·7-129·9). Urine was rtPCR reactive up to 14·5 days (10·5-20·3) and saliva up to 26·4 days (19·7-38·7). Zika virus IgM persisted for 237·7 days (128·7-459·5) from estimated time since plasma NAAT-detectable infection. Zika virus RNA fell below detectable limits more rapidly in the saliva of participants with pre-existing dengue virus IgG than in those without. Of 25 donors identified pre-seroconversion with symptom data at the first or second study visit, 16 (64%) developed multiple Zika virus-related symptoms after asymptomatic index donations, compared with nine (36%) of 25 donors detected after seroconversion. INTERPRETATION: Determination of viral marker persistence is enhanced by follow-up of blood donors who are pre-symptomatic or asymptomatic, Zika virus RNA-positive, and antibody negative. Zika virus RNA persists in red blood cells for several months following clearance from plasma and body fluids, and replicate, highly sensitive NAATs extend RNA detection in all compartments. Whole blood testing can extend detection of acute infection for diagnostics and monitoring of pregnant women, sexual partners, and travellers. FUNDING: National Heart, Lung, and Blood Institute, Biomedical Advanced Research and Development Authority.

Evolving viral and serological stages of Zika virus RNA-positive blood donors and estimation of incidence of infection during the 2016 Puerto Rican Zika epidemic: an observational cohort study.

BACKGROUND: Puerto Rico began screening blood donations for Zika virus RNA with nucleic acid amplification tests (NAATs) on April 3, 2016, because of an emerging Zika virus outbreak. We followed up positive donors to assess the dynamics of viral and serological markers during the early stages of Zika virus infection and update the estimate of infection incidence in the Puerto Rican population during the outbreak. METHODS: Blood donations from volunteer donors in Puerto Rico were screened for the presence of Zika virus RNA using the cobas Zika NAAT. Positive donations were further tested to confirm infection, estimate viral load, and identify Zika virus-specific IgM antibodies. Individuals with positive blood donations were invited to attend follow-up visits. Donations with confirmed infection (defined as detection of Zika virus RNA or IgM on additional testing of index or follow-up samples) were assessed for stage of infection according to Zika virus RNA detectability in simulated minipools, viral load, and Zika virus IgM status. A three-step process was used to estimate the mean duration of NAAT reactivity of Zika virus in human plasma from individuals identified pre-seroconversion with at least one follow up visit and to update the 2016 incidence estimate of Zika virus infection. FINDINGS: Between April 3 and Dec 31, 2016, 53 112 blood donations were screened for Zika virus, of which 351 tested positive, 339 had confirmed infections, and 319 could be staged. Compared with IgM-positive index donations (n=110), IgM-negative index donations (n=209) had higher mean viral loads (1·1 × 106vs 8·3 × 104 international units per mL) and were more likely to be detected in simulated minipools (93% [n=194] vs 26% [n=29]). The proportions of donations with confirmed infections that had viral RNA detected only in individual-donation NAATs (ie, not in simulated minipools) and were IgM positive increased as the epidemic evolved. The estimated mean duration of NAAT detectability in the 140 donors included in the follow-up study was 11·70 days (95% CI 10·06-14·36). Applying this detection period to the observed proportion of donations that were confirmed NAAT positive yielded a Zika virus seasonal incidence estimate of 21·1% (95% CI 18·1-24·1); 768 101 infections in a population of 3 638 773 in 2016. INTERPRETATION: Characterisation of early Zika virus infection has implications for blood safety because infectivity of blood donations and utility of screening methods likely correlate with viral load and serological stage of infection. Our findings also have implications for diagnostic testing, public health surveillance, and epidemiology, and we estimate that around 21% of the Puerto Rican population was infected during the 2016 outbreak. FUNDING: Biomedical Advanced Research and Development Authority, National Heart, Lung, and Blood Institute.

Laboratory Measurements of the Wave-Induced Motion of Plastic Particles: Influence of Wave Period, Plastic Size and Plastic Density.

The transport of plastic particles from inland sources to the oceans garbage patches occurs trough coastal regions where the transport processes depend highly on wave-induced motions. In this study, experimental measurements of the plastic particles wave-induced Lagrangian drift in intermediate water depth are presented investigating the influence of the wave conditions, particle size and density on the motion of relatively large plastic particles. A large influence of the particle density is observed causing particles to float or sink for relative densities lower and larger than water respectively. The measured net drift of the floating particles correlates well with theoretical solutions for particle Stokes drift, where the net drift is proportional to the square of the wave steepness. Floating particles remain at the free water surface because of buoyancy and no evidence of any other influence of particle inertia on the net drift is observed. Nonfloating particles move close to the bed with lower velocity magnitudes than the floating particles' motion at the free surface. The drift of nonfloating particles reduces with decreasing wave number, and therefore wave steepness.

Use of Blood Donor Screening Data to Estimate Zika Virus Incidence, Puerto Rico, April-August 2016.

Puerto Rico has been heavily impacted by Zika virus, a mosquitoborne flavivirus that emerged in the Americas during 2015. Although most persons with Zika virus show no symptoms, the virus can cause neurologic and other complications, including fetal microcephaly. Local Zika virus transmission in Puerto Rico has been reported since December 2015. To prevent transfusion-associated transmission, local blood collection ceased in March 2016 but resumed in April 2016 after Zika virus screening of blood donations became available. Using data from screening of blood donations collected by the 2 largest blood centers in Puerto Rico during April 3-August 12, 2016, and assuming a 9.9-day duration of viremia, we estimated that 469,321 persons in Puerto Rico were infected during this period, for an estimated cumulative incidence of 12.9%. Results from blood donation screening during arboviral outbreaks can supplement routine clinical and surveillance data for improved targeting of prevention efforts.

Screening of Blood Donations for Zika Virus Infection - Puerto Rico, April 3-June 11, 2016.

Transfusion-transmitted infections have been documented for several arboviruses, including West Nile and dengue viruses (1). Zika virus, a flavivirus transmitted primarily by Aedes aegypti mosquitoes that has been identified as a cause of congenital microcephaly and other serious brain defects (2), became recognized as a potential threat to blood safety after reports from a 2013-2014 outbreak in French Polynesia. Blood safety concerns were based on very high infection incidence in the population at large during epidemics, the high percentage of persons with asymptomatic infection, the high proportion of blood donations with evidence of Zika virus nucleic acid upon retrospective testing, and an estimated 7-10-day period of viremia (3). At least one instance of transfusion transmission of Zika virus has been documented in Brazil after the virus emerged there, likely in 2014 (4). Rapid epidemic spread has followed to other areas of the Americas, including Puerto Rico.

Tratamiento quirúrgico de las metatarsalgias mecánicas mediante cirugía percutánea / Traitement chirurgical des métatarsalgies mécaniques par chirurgie percutanée / Surgical treatment of mechanical metatarsalgias through percutaneous surgery

Introducción: las metatarsalgias mecánicas refractarias a tratamiento ortopédico precisan de tratamiento quirúrgico. Presentamos nuestra experiencia mediante la cirugía percutánea. Objetivo: mostrar la efectividad de las osteotomías distales percutáneas (DMMO) en el tratamiento de las metatarsalgias mecánicas. Método: estudio retrospectivo de 100 pacientes intervenidos de metatarsalgias mecánicas entre enero de 2012 y diciembre de 2013, con una media de edad de 57 años. El seguimiento mínimo fue de 1 año de evolución. Las metatarsalgias mecánicas se clasificaron según la fase de la marcha en segundo y tercer rocker. Se valoró clínicamente la desaparición de las queratosis plantares, la desaparición del dolor plantar con la deambulación, el abandono de las plantillas previas, y radiográficamente la fórmula metatarsal y la consolidación de las osteotomías. Resultados: en las metatarsalgias de segundo rocker se obtuvo un 90 % de buenos o muy buenos resultados con un 10 por ciento de complicaciones, principalmente metatarsalgia de transferencia. En las metatarsalgias de tercer rocker un 85 por ciento de buenos o muy buenos resultados y un 15 por ciento de complicaciones predominantemente la metatarsalgia de transferencia. Conclusiones: las osteotomías distales percutáneas parecen ser una técnica aceptable para el tratamiento de les metatarsalgias mecánicas al proporcionar unos buenos resultados clínicos y radiológicos. Es importante la curva de aprendizaje dado que no es una técnica exenta de complicaciones(AU)

Introduction: mechanical metatarsalgias difficult to orthopedic treatment require surgical treatment. We report our experience with percutaneous surgery. Objectivs: show the effectiveness of percutaneous distal osteotomy in the treatment of mechanical metatarsalgias. Methods: a retrospective study of 100 patients undergoing mechanical metatarsalgias from January to December 2013, with an average age of 57 years. Minimum follow-up was 1 year of evolution. Mechanical metatarsalgias were classified according to the stage of walking, second and third rocker. It was clinically assessed the disappearance of plantar keratosis, plantar pain when walking, as well as abandoning previous templates. Radiographically the metatarsal formula and consolidation of the osteotomy were evaluated. Results: in second rocker metatarsalgias, 90 percent had good or excellent results with 10 percent complications, mainly transfer metatarsalgia. In third rocker metatarsalgias 85 percent had good or very good results and 15 percent complications, mainly the transfer metatarsalgia. Conclusions: percutaneous distal osteotomies appear to be an acceptable technique for mechanical metatarsalgias treatment to provide good clinical and radiological results. Learning curve is important since it is not free of complications(AU)

Introduction: les métatarsalgies mécaniques de nature réfractaire exigent un traitement chirurgical. Nous présentons ici notre expérience avec la chirurgie percutanée. Objectif: le but de ce travail est de montrer l'efficacité des ostéotomies distales percutanées dans le traitement des métatarsalgies de type mécanique. Méthode: une étude rétrospective de 100 patients (âge moyen de 57 ans) atteints de métatarsalgies d'origine mécanique a été réalisée entre janvier et décembre 2013. Le suivi minimal a eu un an de durée. Les métatarsalgies mécaniques ont été classées selon phase de la marche (phase 2, second-rocker et phase 3, third-rocker). On a évalué du point de vue clinique la disparition des kératoses plantaires, la disparition de la douleur plantaire au cours de la marche et l'abandon des semelles, et du point de vue radiographique la formule métatarsienne et la consolidation des ostéotomies. Résultats: dans les métatarsalgies de second-rocker (métatarsalgies statiques), on a obtenu de bons et très bons résultats (90 pourcent) et très peu de complications (10 pourcent) telles que les métatarsalgies de transfert. Dans les métatarsalgies de third-rocker (métatarsalgies propulsives), on a obtenu de bons et très bons résultats (85 pourcent) et très peu de complications (15 pourcent), telles que les métatarsalgies de transfert. Conclusions: l'ostéotomie distale percutanée semble être la technique appropriée pour le traitement des métatarsalgies mécaniques, car elle prodigue de très bons résultats cliniques et radiologiques. L'apprentissage est très important, parce que cette technique n'est pas exceptée de complications(AU)

Cirugía percutánea de Hallux valgus moderados y severos mediante osteotomía en chevron modificada / Chirurgie percutanée de l'hallux valgus modéré et sévère par ostéotomie en chevron modifiée / Moderate Hallux Valgus percutaneous surgery to severe modified chevron osteotomy

Introducción: la osteotomía en chevron modificada ha estado presente en numerosos artículos que tratan sobre el tratamiento de los Hallux valgus moderados y severos. Se presenta nuestra experiencia mediante la cirugía percutánea. Objetivo: mostrar la efectividad de la osteotomía en chevron modificada mediante cirugía percutánea en el tratamiento de los Hallux valgus moderados y severos. Método: estudio retrospectivo de 28 pacientes intervenidos de Hallux valgus moderados y severos entre abril y diciembre de 2013, con una media de edad de 59 años. El seguimiento mínimo fue de 1 año de evolución. Se valoró el ángulo de Hallux valgus, el intermetatarsiano y el ángulo metatarso distal articular y se determinó la posición de los sesamoideos. La osteotomía en chevron se fijó con un tornillo canulado de doble rosca también de forma percutánea. Resultados: el ángulo de Hallux valgus pasó de 34,96° ± 9,8 en el preoperatorio a 12,6° ± 5,2 en el posoperatorio. El ángulo intermetatarsiano de 15,56° ± 3,2 en el preoperatorio se redujo a 10,44° ± 3,1 en el posoperatorio. El ángulo ángulo metatarso distal articular pasó de 21,20° ± 6,0 en el preoperatorio a 9,36° ± 6,5 en el posoperatorio. Conclusiones: la osteotomía en chevron modificada percutánea tiene resultados similares a los de la cirugía abierta, con la gran ventaja de no realizar incisiones en el pie, lo que disminuye complicaciones habituales como la infección. Es importante la curva de aprendizaje dado que no es una técnica exenta de complicaciones(AU)

Introduction: modified chevron osteotomy has been present in numerous articles dealing with the treatment of moderate and severe Hallux valgus. Our experience with percutaneous surgery is presented here. Objective: show the effectiveness of modified chevron osteotomy with percutaneous surgery in the treatment of moderate and severe Hallux valgus. Methods: a retrospective study was conducted on 28 patients undergoing moderate and severe hallux valgus from April to December 2013, with an average age of 59 years. Minimum follow-up period was 1 year of evolution. Hallux valgus angle, intermetatarsal and distal metatarsal joint angle were evaluated and sesamoid position was determined. Chevron osteotomy was fixed with a cannulated double threaded screw also percutaneously. Results: Hallux valgus angle increased from 34.96 ± 9.8° preoperatively to 12.6° ± 5.2 postoperatively. The intermetatarsal angle of 15.56° ± 3.2 preoperatively decreased to 10.44 ± 3.1° postoperatively. The distal metatarsal articular angle increased from 21.20° ± 6.0 preoperatively to 6.5 ± 9.36° postoperatively. Conclusions: percutaneous modified chevron osteotomy has similar results to those of open surgery, with the great advantage of not making incisions in the foot, reducing common complications such as infection. Learning curve is important since it is not free of complications(AU)

Introduction: l'ostéotomie en chevron modifiée a été présente dans nombreux articles abordant le traitement de l'hallux valgus modéré et sévère. Un nouveau traitement par chirurgie percutanée est présenté. Objectif: le but de ce travail est de montrer l'efficacité de l'ostéotomie en chevron modifiée par chirurgie percutanée dans le traitement de l'hallux valgus modéré et sévère. Méthode: Une étude rétrospective de 28 patients (âge moyen de 59 ans) traités pour hallux valgus modéré et sévère a été réalisée entre avril et décembre 2013. Le suivi minimal a eu un an de durée. On a évalué l'angle de valgus, l'angle intermétatarsien et l'angle articulaire distal métatarsien, et on a également déterminé la position des sésamoïdiens. L'ostéotomie en chevron a été fixée par vis canulé à double filetage par voie percutanée. Résultats: l'angle de valgus a changé de 34.96° ± 9.8 en préopératoire à 12.6° ± 5.2 en postopératoire. L'angle intermétatarsien est réduit de 15.56° ± 3.2 en préopératoire à 10.44° ± 3.1 en postopératoire. L'angle articulaire distal métatarsien a diminué de 21.20° ± 6.0 en préopératoire à 9.36° ± 6.5 en postopératoire. Conclusions: l'ostéotomie percutanée en chevron modifiée a des résultats similaires à la chirurgie ouverte. L'avantage le plus remarquable de cette technique est l'absence d'incisions importantes au niveau du pied, ce qui diminue la survenue des complications habituelles telles que l'infection. Toutefois, la courbe d'apprentissage est très importante, car cette technique n'est pas exceptée de complications(AU)