Bycatch and discards in the artisanal shrimp trawl fishery in Northern Peru.

This study analyses the bycatch composition of an artisanal shrimp trawl fleet operating between Cabo Blanco and Máncora in Northern Peru between April 2019 and March 2020. A total of 300 hauls were analysed with respect to target catch and bycatch (consisting of other commercial species, discards, and macroalgae). A total of 277 species were recorded including 111 species of fish, 65 species of molluscs, 51 species of crustaceans, 22 species of algae, 12 species of cnidarian, 9 species of echinoderms, 4 species of Bryozoa and 3 species of polychaeta. Capture per unit effort (CPUE, kg.h-1) was highest for fish, followed by crustaceans, algae and molluscs. The target species Penaeus californiensis coffee shrimp constituted 17.8% of the overall catch,82.2% represented bycatch, and 50.6% represented discards. Coffee shrimps were more abundant in June and November 2019 and in January and February 2020. Highest bycatch CPUE occurred in May, June and December 2019. The most abundant species in the bycatch throughout the study period were sand perch (Diplectrum conceptione, 16% weight of the total catch), the macroalgae caulerpa (Caulerpa filiformis, 13%), sole flounder (Etropus ectenes, 6.4%), Pacific drum (Larimus pacificus, 5.7%), and lumptail searobin (Prionotus stephanophrys, 5.1%). Overall, the contribution of sand perch and flounder, exceeded the weight of coffee shrimp, therefore the interpretation that shrimp is the sole target species needs to be revised. The number of discarded species per month increased towards the spring months with the highest value in November. This study represents the first characterisation of bycatch in the artisanal trawling fishery in the Piura region in northern Peru and reveals a high proportion of bycatch in the fishery but also hints at potential temporal management measures that could be imposed to reduce the levels of bycatch. For example, the months of May and December had the greatest bycatch to shrimp ratios and the fishery could potentially be closed to avoid high bycatch risk, however, longer term information is needed to assess if the trends observed in bycatch are similar over longer periods of time. The species characterisation of bycatch also provides information for the design of modified nets which would target the reduction of small fish present in the catch.

A small step or a giant leap: Accounting for settlement delay and dispersal in restoration planning.

Understanding larval duration and hence dispersal potential of the European oyster Ostrea edulis is crucial to inform restoration strategies. Laval duration has an obligatory period of maturity to pediveliger (when larvae are ready to settle), but also an unknown period until metamorphosis is triggered by a settlement cue. The extent to which larvae can prolong the pediveliger period and delay metamorphosis has not been studied. Here we show that O. edulis larvae can delay metamorphosis for a period of 11 days, while retaining the capability to settle in high proportions when presented with a suitable settlement cue. O. edulis larvae are likely to be able to delay metamorphosis even further, since 80% of larvae in the control treatment were still alive when the experiment was terminated at day 14. The results indicate the ability of O. edulis larvae to more than double pelagic duration and probably further delay metamorphosis. We discuss these findings in the context of larval mortality, and the importance of O. edulis' larval settlement requirements for dispersal potential, recruitment success and connectivity of restoration sites.

Optimising recruitment in habitat creation for the native European oyster (Ostrea edulis): Implications of temporal and spatial variability in larval abundance.

European oyster (Ostrea edulis) restoration often requires the timely deployment of shell habitat for larval settlement. To inform this increasingly popular process, the present study investigated temporal and spatial abundance patterns of O. edulis larvae in a rare commercial fishery (Loch Ryan, Scotland, UK). Patterns in larval abundance were analysed against variability in temperature, salinity, chlorophyll, oxygen, tidal/moon phase, light, date, and location. 'Temperature sum' (sum total of degrees per day above 7 °C) was the most significant seasonal predictor of larval abundance; with a peak at 617 degree-days. Oyster larval abundance did not significantly vary between oyster bed and non-bed habitats but was significantly higher in the mid and near-surface part of the water column. The findings are discussed in the context of emerging international restoration initiatives and have implications for: where habitat restoration would be successful; the prediction of larval connectivity between sites; and a transferable indicator to optimise shell-habitat deployment timing.

Neighborhood Violence Impacts Disease Control and Surveillance: Case Study of Cali, Colombia from 2014 to 2016.

Arboviruses are responsible for a large burden of disease globally and are thus subject to intense epidemiological scrutiny. However, a variable notably absent from most epidemiological analyses has been the impact of violence on arboviral transmission and surveillance. Violence impedes surveillance and delivery of health and preventative services and affects an individual's health-related behaviors when survival takes priority. Moreover, low and middle-income countries bear a disproportionately high burden of violence and related health outcomes, including vector borne diseases. To better understand the epidemiology of arboviral outbreaks in Cali, Colombia, we georeferenced chikungunya (CHIKV), dengue (DENV), and Zika (ZIKV) viral cases from The National System of Surveillance in Public Health between October 2014 and April 2016. We extracted homicide data from the municipal monthly reports and kernel density of homicide distribution from IdeasPaz. Crucially, an overall higher risk of homicide is associated with increased risk of reported DENV, lower rates of acute testing, and higher rates of lab versus clinical discordance. In the context of high violence as a potential barrier to access to preventive health services, a community approach to improve health and peace should be considered.

Physical examination of dizziness in athletes after a concussion: A descriptive study.

BACKGROUND: Dizziness is commonly reported after concussion. With the forces experienced at the time of the injury, several anatomical locations may have been altered, causing dizziness. OBJECTIVE: Describe an objective examination and the types of impairment/dysfunction implicated by the results of clinical examination tests in subjects with dizziness after a concussion. DESIGN: Cross-Sectional. METHODS: Athletes between ages 10-23 were enrolled with a diagnosis of concussion. An examination was completed to identify areas potentially contributing to dizziness, including tests of oculomotor control, the vestibular system, neuromotor control, and musculoskeletal components of the cervical spine. Descriptive analyses were completed to define the anatomical areas/types of dysfunction identified by positive findings of the examination tests. RESULTS: All (n = 41; 100%) subjects had examination findings consistent with central dysfunction. Of these, 36 (97.8%) had oculomotor control deficits; 29 (70.7%) demonstrated motion sensitivity; and 6 (15%) had central vestibular deficits. Nineteen (46.3%) had peripheral dysfunction, including 18 (43.9%) with unilateral hypofunction, and 2 (4.9%) with Benign Paroxysmal Positional Vertigo. Thirty-four (82.9%) had cervical dysfunction, with 11 (26.8%) presenting with cervicogenic dizziness, and 31 (75.6%) with altered neuromotor control. CONCLUSIONS: Functional injury to centrally-mediated pathways, specifically oculomotor control, and afferent and efferent pathways in the cervical spine are commonly identified through clinical examination tests in individuals with a complaint of dizziness post-concussion. According to results presented here, a high majority (90%) of the participants demonstrated dizziness that appeared to be multifactorial in nature and was not attributable to one main type of dysfunction. The common pathways between the systems make it difficult to isolate only one anatomical area as a contributor to dizziness.

Community context and sub-neighborhood scale detail to explain dengue, chikungunya and Zika patterns in Cali, Colombia.

BACKGROUND: Cali, Colombia has experienced chikungunya and Zika outbreaks and hypoendemic dengue. Studies have explained Cali's dengue patterns but lack the sub-neighborhood-scale detail investigated here. METHODS: Spatial-video geonarratives (SVG) with Ministry of Health officials and Community Health Workers were collected in hotspots, providing perspective on perceptions of why dengue, chikungunya and Zika hotspots exist, impediments to control, and social outcomes. Using spatial video and Google Street View, sub-neighborhood features possibly contributing to incidence were mapped to create risk surfaces, later compared with dengue, chikungunya and Zika case data. RESULTS: SVG captured insights in 24 neighborhoods. Trash and water risks in Calipso were mapped using SVG results. Perceived risk factors included proximity to standing water, canals, poverty, invasions, localized violence and military migration. These risks overlapped case density maps and identified areas that are suitable for transmission but are possibly underreporting to the surveillance system. CONCLUSION: Resulting risk maps with local context could be leveraged to increase vector-control efficiency- targeting key areas of environmental risk.

Differential diagnosis of dizziness after a sports-related concussion based on descriptors and triggers: an observational study.

BACKGROUND: Dizziness is often reported after a sports-related concussion. Forces experienced at the time of the concussion can cause an injury to multiple anatomical areas, including the central nervous system, the vestibular system, and the cervical spine, each of which is sufficient to cause dizziness. Medical professionals routinely use the subjective history to develop hypotheses about what may be causing a patient's dizziness. No previous studies have attempted to differentiate the source of the dizziness through precise patient descriptors or the triggers of dizziness. METHODS: A structured symptom questionnaire was developed through purposive exploration of relevant literature for common dizziness quality descriptors and triggers. This questionnaire was used to interview a sample of 86 adolescent athletes (12-19 years of age) with a sports-related concussion between August 2013 and April 2014. Exploratory Latent Class Analysis was used to uncover latent constructs within the 15 dizziness descriptors and 11 dizziness triggers. The covariates sex, attention deficit hyperactivity disorder, and number of days between the concussion and the assessment were added to the model to estimate if these variables influenced class membership probabilities. RESULTS: Thirty-two (36 %) of the patients interviewed did not report a complaint of dizziness but did affirm one or more of the other descriptors. Three classes of dizziness based on dizziness quality descriptors and three classes based on dizziness triggers were identified by the analysis. Neither the classes of descriptors nor the classes of triggers enabled differentiation based on anatomical etiology of the dizziness. CONCLUSIONS: Patient description of dizziness is limited in its ability to assist in differential diagnosis based on anatomical location for athletes with concussion. This may be because more than one area is contributing to the dizziness or because concussed adolescents have difficulty describing the way that they feel. In this case, solely relying on the patient to provide a description of dizziness to develop the formation of hypotheses and lead the direction of objective tests is inappropriate. If the scope of the objective assessment is limited by the patient description of dizziness, it is likely that areas of dysfunction may be overlooked.

Sickle cell trait protects against Plasmodium falciparum infection.

Although sickle cell trait protects against severe disease due to Plasmodium falciparum, it has not been clear whether sickle trait also protects against asymptomatic infection (parasitemia). To address this question, the authors identified 171 persistently smear-negative children and 450 asymptomatic persistently smear-positive children in Bancoumana, Mali (June 1996 to June 1998). They then followed both groups for 2 years using a cohort-based strategy. Among the 171 children with persistently negative smears, the median time for conversion to smear-positive was longer for children with sickle trait than for children without (274 vs. 108 days, P < 0.001; Cox hazard ratio = 0.56, 95% confidence interval: 0.33, 0.96; P = 0.036). Similar differences were found in the median times to reinfection after spontaneous clearance without treatment (365 days vs. 184 days; P = 0.01). Alternatively, among the 450 asymptomatic children with persistently positive smears, the median time for conversion to smear-negative (spontaneous clearance) was shorter for children with sickle trait than for children without (190 vs. 365 days; P = 0.02). These protective effects of sickle trait against asymptomatic P. falciparum infection under conditions of natural transmission were demonstrable using a cohort-based approach but not when the same data were examined using a cross-sectional approach.

Cockroach exposure independent of sensitization status and association with hospitalizations for asthma in inner-city children.

BACKGROUND: Children with asthma living in urban environments experience disproportionately high asthma hospitalization rates. Excessive exposure to perennial allergens, including cockroach and house dust mite (HDM), have been implicated, but data are limited. OBJECTIVE: To examine the relation between cockroach and HDM exposure and measures of asthma morbidity and health care utilization. METHODS: Participants included 86 atopic asthmatic children living in New Orleans, Louisiana. Sensitization status was determined by means of serum specific IgE testing, and vacuum dust samples were collected for allergen analysis. Logistic regression analysis was used to assess the odds of persistent wheezing, emergency department visits, and asthma hospitalization in those with high vs low levels of allergen exposure. RESULTS: Approximately 44% and 40% of children were exposed to Bla g 1 levels greater than 2 U/g and HDM levels greater than 2 µg/g, respectively, and 24% reported at least 1 hospitalization in the previous 4 months. The median Bla g 1 level was significantly higher in the homes of children hospitalized compared with those with no hospital admissions (7.2 vs 0.8 U/g). In multivariable models, the odds of hospitalization were significantly higher in children exposed to Bla g 1 levels greater than 2 U/g (adjusted odds ratio, 4.2; 95% confidence interval, 1.24-14.17), independent of sensitization status. Exposure to HDMs was not associated with any measure of morbidity. CONCLUSIONS: Exposure to cockroach allergen was strongly associated with increased hospitalization in children with asthma. This effect cannot be explained entirely by IgE-mediated inflammation. Controlled interventional trials are needed to determine whether isolated cockroach abatement improves asthma control.

Plasmodium vivax sporozoite production in Anopheles albimanus mosquitoes for vaccine clinical trials.

Vaccine development for Plasmodium vivax malaria is underway. A model to assess the protective efficacy of vaccine candidates in humans is urgently needed. Given the lack of continuous P. vivax cultures, we developed a system to infect Anopheles albimanus mosquitoes using blood from P. vivax-infected patients and determined parameters for challenge of malaria-naive volunteers by mosquito bite. Absence of co-infections in parasitized blood was confirmed by tests consistent with blood bank screening. A total of 119 experiments were conducted using batches of 900-4,500 mosquitoes fed by an artificial membrane feeding method. Optimal conditions for mosquito probing and infection were determined. Presence of oocyst and sporozoites were assessed on Days 7-8 and 14-15, respectively, and conditions to choose batches of infected mosquitoes for sporozoite challenge were established. Procedures to infect volunteers took a 2-hour period including verification of inoculum dose. Anopheles albimanus mosquitoes represent a valuable resource for P. vivax sporozoite challenge of volunteers.

Antibody response against Anopheles albimanus (Diptera: Culicidae) salivary protein as a measure of mosquito bite exposure in Haiti.

Antibodies against arthropod saliva have shown to be a good marker of bite exposure. Because Anopheles albimanus Wiedemann (Diptera: Culicidae) is the principal malaria vector in Haiti, we evaluated the immune response against salivary gland extract (SGE) of this species in malaria-positive and malaria-negative subjects from this country. The results showed that the level of anti-SGE immunoglobulin (Ig)G antibodies was higher in patients with clinical malaria than those in malaria uninfected people living in the same region. In addition, a significant positive correlation between the level of anti-An. albimanus IgG and IgM antibody levels was observed. These results suggest that antibodies against An. albimanus saliva, especially IgG, are useful markers of mosquito bite exposure in Haiti.

Altered immune responses in rhesus macaques co-infected with SIV and Plasmodium cynomolgi: an animal model for coincident AIDS and relapsing malaria.

BACKGROUND: Dual epidemics of the malaria parasite Plasmodium and HIV-1 in sub-Saharan Africa and Asia present a significant risk for co-infection in these overlapping endemic regions. Recent studies of HIV/Plasmodium falciparum co-infection have reported significant interactions of these pathogens, including more rapid CD4+ T cell loss, increased viral load, increased immunosuppression, and increased episodes of clinical malaria. Here, we describe a novel rhesus macaque model for co-infection that supports and expands upon findings in human co-infection studies and can be used to identify interactions between these two pathogens. METHODOLOGY/PRINCIPAL FINDINGS: Five rhesus macaques were infected with P. cynomolgi and, following three parasite relapses, with SIV. Compared to macaques infected with SIV alone, co-infected animals had, as a group, decreased survival time and more rapid declines in markers for SIV progression, including peripheral CD4+ T cells and CD4+/CD8+ T cell ratios. The naïve CD4+ T cell pool of the co-infected animals was depleted more rapidly than animals infected with SIV alone. The co-infected animals also failed to generate proliferative responses to parasitemia by CD4+ and CD8+ T cells as well as B cells while also having a less robust anti-parasite and altered anti-SIV antibody response. CONCLUSIONS/SIGNIFICANCE: These data suggest that infection with both SIV and Plasmodium enhances SIV-induced disease progression and impairs the anti-Plasmodium immune response. These data support findings in HIV/Plasmodium co-infection studies. This animal model can be used to further define impacts of lentivirus and Plasmodium co-infection and guide public health and therapeutic interventions.

Safety of upper-room ultraviolet germicidal air disinfection for room occupants: results from the Tuberculosis Ultraviolet Shelter Study.

OBJECTIVES: We evaluated the safety of room occupants in the Tuberculosis Ultraviolet Shelter Study (TUSS), a double-blind, placebo-controlled field trial of upper-room ultraviolet germicidal irradiation (UVGI) at 14 homeless shelters in six U.S. cities from 1997 to 2004. METHODS: Data collection involved administering questionnaires regarding eye and skin irritation to a total of 3,611 staff and homeless study subjects. RESULTS: Among these subjects, there were 223 reports of eye or skin symptoms. During the active UV period, 95 questionnaires (6%) noted such symptoms, and during the placebo period, 92 questionnaires (6%) did so. In the 36 remaining cases, either the UV period when symptoms took place was unknown or the symptoms spanned both periods. There was no statistically significant difference in the number of reports of symptoms between the active and placebo periods. One definite instance of UV-related keratoconjunctivitis occurred, resulting from a placement of a bunk bed in a dormitory where a single bed had been used when the UV fixtures were first installed. CONCLUSIONS: These findings demonstrate that careful application of upper-room UVGI can be achieved without an apparent increase in the incidence of the most common side effects of accidental UV overexposure.

Effects of anticoagulants on Plasmodium vivax oocyst development in Anopheles albimanus mosquitoes.

Artificial membrane feeding (AMF) assays are used to determine malaria transmission-blocking activity in Anopheles. The purpose of this study was to determine the effect of the most widely used anticoagulants, EDTA and heparin, on development of the Plasmodium vivax sporogonic cycle. Blood samples collected from 60 patients carrying P. vivax infections were used to feed An. albimanus using AMF. Seven days after feeding, mosquitoes were dissected to assess mosquito infection. Mosquitoes fed with blood containing EDTA showed a lower mean oocyst number as compared with those fed blood with heparin. However, this effect was minimized upon reduction of EDTA concentrations in the serum. This result may be explained by the fact that microgametocytes require Ca(2+), Mn(2+), and Mg(+2) to activate enzymes important for exflagellation process and for motility of ookinetes. We therefore recommend that heparin be used as the anticoagulant of choice for blood used in AMF assays.

Testosterone correlates with Venezuelan equine encephalitis virus infection in macaques.

Here we briefly report testosterone and cytokine responses to Venezuelan equine encephalitis virus (VEEV) in macaques which were used as part of a larger study conducted by the Department of Defense to better characterize pathological responses to aerosolized VEEV in non-human primates. Serial samples were collected and analyzed for testosterone and cytokines prior to and during infection in 8 captive male macaques. Infected animals exhibited a febrile response with few significant changes in cytokine levels. Baseline testosterone levels were positively associated with viremia following exposure and were significantly higher than levels obtained during infection. Such findings suggest that disease-induced androgen suppression is a reasonable area for future study. Decreased androgen levels during physiological perturbations may function, in part, to prevent immunosuppression by high testosterone levels and to prevent the use of energetic resources for metabolically-expensive anabolic functions.

Detection of Giardia duodenalis antigen in human fecal eluates by enzyme-linked immunosorbent assay using polyclonal antibodies

The present study developed and standardized an enzime-linked immunosorbent assay (ELISA) to detect Giardia antigen in feces using rabbit polyclonal antibodies. Giardia cysts were purified from human fecal samples by sucrose and percoll gradients. Gerbils (Meriones unguiculatus) were infected to obtain trophozoites. Rabbits were inoculated with either cyst or trophozoite antigens of 14 Colombian Giardia isolates to develop antibodies against the respective stages. The IgG anti-Giardia were purified by sequential caprylic acid and ammonium sulfate precipitation. A portion of these polyclonal antibodies was linked to alkaline phosphatase (conjugate). One hundred and ninety six samples of human feces, from different patients, were tested by parasitologic diagnosis: 69 were positive for Giardia cysts, 56 had no Giardia parasites, and 71 revealed parasites other than Giardia. The optimal concentration of polyclonal antibodies for antigen capture was 40 æg/ml and the optimal conjugate dilution was 1:100. The absorbance cut-off value was 0.24. The parameters of the ELISA test for Giardia antigen detection were: sensitivity, 100 percent (95 percent CI: 93.4-100 percent); specificity, 95 percent (95 percent CI: 88.6-97.6 percent); positive predictive value, 91 percent (95 percent CI: 81.4-95.9 percent); and negative predictive value, 100 percent (95 percent CI: 96.1-100 percent). This ELISA will improve the diagnosis of Giardia infections in Colombia and will be useful in following patients after treatment

Detection of Giardia duodenalis antigen in human fecal eluates by enzyme-linked immunosorbent assay using polyclonal antibodies.

The present study developed and standardized an enzime-linked immunosorbent assay (ELISA) to detect Giardia antigen in feces using rabbit polyclonal antibodies. Giardia cysts were purified from human fecal samples by sucrose and percoll gradients. Gerbils (Meriones unguiculatus) were infected to obtain trophozoites. Rabbits were inoculated with either cyst or trophozoite antigens of 14 Colombian Giardia isolates to develop antibodies against the respective stages. The IgG anti-Giardia were purified by sequential caprylic acid and ammonium sulfate precipitation. A portion of these polyclonal antibodies was linked to alkaline phosphatase (conjugate). One hundred and ninety six samples of human feces, from different patients, were tested by parasitologic diagnosis: 69 were positive for Giardia cysts, 56 had no Giardia parasites, and 71 revealed parasites other than Giardia. The optimal concentration of polyclonal antibodies for antigen capture was 40 g/ml and the optimal conjugate dilution was 1:100. The absorbance cut-off value was 0.24. The parameters of the ELISA test for Giardia antigen detection were: sensitivity, 100% (95% CI: 93.4-100%); specificity, 95% (95% CI: 88.6-97.6%); positive predictive value, 91% (95% CI: 81.4-95.9%); and negative predictive value, 100% (95% CI: 96.1-100%). This ELISA will improve the diagnosis of Giardia infections in Colombia and will be useful in following patients after treatment.

Cytokine responses during acute simian Plasmodium cynomolgi and Plasmodium knowlesi infections.

Experimental infection of non-human primates with simian malaria parasites offers a controlled system to study malarial immunity. Plasmodium cynomolgi (P. vivax-like) and P. knowlesi (P. falciparum-like) infections in the rhesus monkey were used as a model to test the hypothesis that initial acute infection stimulates type 1/pro-inflammatory cytokine expression followed by a gradual type 2/anti-inflammatory response upon re-infection. This study analyzed cytokine gene expression (interleukin-12, interferon-gamma, tumor necrosis factor-alpha = type 1; interleukin-4, interleukin-10 = type 2) using a semi-quantitative reverse transcriptase-polymerase chain reaction in monkeys infected with each of the parasites (three per group). Clinicoparasitologic and serologic parameters were also monitored. Monkeys were re-infected to assess whether enhanced immunity could increase parasite clearance. The immune response to P. cynomolgi infection in rhesus monkeys seemed to be mediated by anti-parasite, pro-inflammatory responses during primary infection with a transition to protective type 2 responses after repeat infection. The immune responses to P. knowlesi infection were more varied. Anti-inflammatory responses were more prevalent during primary infection. Repeat infection stimulated a wide variety of responses; most included expression of tumor necrosis factor-alpha, a cytokine that has been associated with inflammatory and host-destructive effects (weight loss, fever, anemia). These observations further confirmed that the simian malaria/rhesus monkey model is well suited for studies on the regulation of immunity to acute Plasmodium infection.