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41 result(s) for "Ryff, Kyle"
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Early Indicators of Fatal Leptospirosis during the 2010 Epidemic in Puerto Rico
Leptospirosis is a potentially fatal bacterial zoonosis that is endemic throughout the tropics and may be misdiagnosed as dengue. Delayed hospital admission of leptospirosis patients is associated with increased mortality. During a concurrent dengue/leptospirosis epidemic in Puerto Rico in 2010, suspected dengue patients that tested dengue-negative were tested for leptospirosis. Fatal and non-fatal hospitalized leptospirosis patients were matched 1:1-3 by age. Records from all medical visits were evaluated for factors associated with fatal outcome. Among 175 leptospirosis patients identified (4.7 per 100,000 residents), 26 (15%) were fatal. Most patients were older males and had illness onset during the rainy season. Fatal case patients first sought medical care earlier than non-fatal control patients (2.5 vs. 5 days post-illness onset [DPO], p < 0.01), but less frequently first sought care at a hospital (52.4% vs. 92.2%, p < 0.01). Although fatal cases were more often diagnosed with leptospirosis at first medical visit (43.9% vs. 9.6%, p = 0.01), they were admitted to the hospital no earlier than non-fatal controls (4.5 vs. 6 DPO, p = 0.31). Cases less often developed fever (p = 0.03), but more often developed jaundice, edema, leg pain, hemoptysis, and had a seizure (p ≤ 0.03). Multivariable analysis of laboratory values from first medical visit associated with fatal outcome included increased white blood cell (WBC) count with increased creatinine (p = 0.001), and decreased bicarbonate with either increased WBC count, increased creatinine, or decreased platelet count (p < 0.001). Patients with fatal leptospirosis sought care earlier, but were not admitted for care any earlier than non-fatal patients. Combinations of routine laboratory values predictive of fatal outcome should be considered in admission decision-making for patients with suspected leptospirosis.
Arbovirus risk perception as a predictor of mosquito-bite preventive behaviors in Ponce, Puerto Rico
Mosquito-borne arboviruses are an important cause of morbidity and mortality in the Caribbean. In Puerto Rico, chikungunya, dengue, and Zika viruses have each caused large outbreaks during 2010–2022. To date, the majority of control measures to prevent these diseases focus on mosquito control and many require community participation. In 2018, the U.S. Centers for Disease Control and Prevention launched the COPA project, a community-based cohort study in Ponce, Puerto Rico, to measure the impact of novel vector control interventions in reducing arboviral infections. Randomly selected households from 38 designated cluster areas were offered participation, and baseline data were collected from 2,353 households between May 2018 and May 2019. Household-level responses were provided by one representative per home. Cross-sectional analyses of baseline data were conducted to estimate 1) the association between arboviral risk perception and annual household expenditure on mosquito control, and 2) the association between arboviral risk perception and engagement in ≥3 household-level risk reduction behaviors. In this study, 27% of household representatives believed their household was at high risk of arboviruses and 36% of households engaged in at least three of the six household-level preventive behaviors. Households where the representative perceived their household at high risk spent an average of$35.9 (95% confidence interval: $ 23.7, $48.1) more annually on mosquito bite prevention compared to households where the representative perceived no risk. The probability of engaging in ≥3 household-level mosquito-preventive behaviors was 10.2 percentage points greater (7.2, 13.0) in households where the representatives perceived high risk compared to those in which the representatives perceived no risk. Paired with other research, these results support investment in community-based participatory approaches to mosquito control and providing accessible information for communities to accurately interpret their risk.
Incompatible Aedes aegypti male releases as an intervention to reduce mosquito population—A field trial in Puerto Rico
Mosquito-transmitted viruses such as dengue are a global and growing public health challenge. Without widely available vaccines, mosquito control is the primary tool for fighting the spread of these viruses. New mosquito control technologies are needed to complement existing methods, given current challenges with scalability, acceptability, and effectiveness. A field trial was conducted in collaboration with the Communities Organized to Prevent Arboviruses project in Ponce, Puerto Rico, to measure entomological and epidemiological effects of reducing Aedes aegypti populations using Wolbachia incompatible insect technique. We packed and shipped Wolbachia -males from California and released them into 19 treatment clusters from September 2020 to December 2020. Preliminary evaluation revealed sub-optimal Wolbachia -male densities and impact on the wild-type population. In 2021, we shifted to a phased release strategy starting in four clusters, reducing the mosquito population by 49% (CI 29–63%). We describe the investigation into male quality and other factors that may have limited the impact of Wolbachia -male releases. Laboratory assays showed a small but significant impact of packing and shipping on male fitness. However, mark-release-recapture assessments suggest that male daily survival rates in the field may have been significantly impacted. We compared induced-sterility levels and suppression of the wild population and found patterns consistent with mosquito population compensation in response to our intervention. Analysis of epidemiological impact was not possible due to very low viral transmission rates during the intervention period. Our entomological impact data provide evidence that Wolbachia incompatible-male releases reduced Ae . aegypti populations, although efficacy will be maximized when releases are part of an integrated control program. With improvement of shipping vessels and shipped male fitness, packing and shipping male mosquitoes could provide a key solution for expanding access to this technology. Our project underscores the challenges involved in large and complex field effectiveness assessments of novel vector control methods.
Surveillance for Chikungunya and Dengue During the First Year of Chikungunya Virus Circulation in Puerto Rico
After chikungunya virus (CHIKV) transmission was detected in Puerto Rico in May 2014, multiple surveillance systems were used to describe epidemiologica trends and CHIKV-associated disease. Of 28 327 cases reported via passive surveillance, 6472 were tested for evidence of CHIKV infection, and results for 4399 (68%) were positive. Of 250 participants in household cluster investigations, 70 (28%) had evidence of recent CHIKV infection. Enhanced surveillance for chikungunya at 2 hospitals identified 1566 patients who tested positive for CHIKV, of whom 10.9% were hospitalized. Enhanced surveillance for fatal cases enabled identification of 31 cases in which CHIKV was detected in blood or tissue specimens. All surveillance systems detected a peak incidence of chikungunya in September 2014 and continued circulation in 2015. Concomitant surveillance for dengue demonstrated low incidence, which had decreased before CHIKV was introduced. Multifaceted chikungunya surveillance in Puerto Rico resolved gaps in traditional passive surveillance and enabled a holistic description of the spectrum of disease associated with CHIKV infection.
HTrack: A new tool to facilitate public health field visits and electronic data capture
Many applications have been developed for electronic data collection. However, offline field navigation tools incorporating secure electronic data capture and field visit tracking are currently scarce. We created an R-Shiny application, HTrack (Household Tracking), for use on encrypted Android devices in the field. The application was implemented in the Communities Organized to Prevent Arboviruses (COPA) project, a study beginning in 2018 to better understand arboviral disease incidence in 38 communities in Puerto Rico. The application was used to navigate to randomly selected structures and capture visit outcomes after conducting multiple visits for participant recruitment. It also served as a bridge to an alternate software, Epi Info, to collect participant-level questionnaire data. This application successfully captured each visit outcome and improved the logistics of field level activities for the COPA project, eliminating the use of paper maps for navigation. We show the development of HTrack and comment on the limitations and strengths of this application and further improvements.
Seroprevalence, Risk Factors, and Rodent Reservoirs of Leptospirosis in an Urban Community of Puerto Rico, 2015
The burden of leptospirosis in Puerto Rico remains unclear due to underreporting. A cross-sectional survey and rodent trapping was performed in a community within San Juan, Puerto Rico to determine the seroprevalence and risk factors for Leptospira infection. The microscopic agglutination test was used to detect anti-Leptospira antibodies as a marker of previous infection. We evaluated Leptospira carriage by quantitative polymerase chain reaction among rodents trapped at the community site. Of 202 study participants, 55 (27.2%) had Leptospira agglutinating antibodies. Among the 55 seropositive individuals, antibodies were directed most frequently against serogroups Icterohaemorrhagiae (22.0%) and Autumnalis (10.6%). Of 18 captured rodents, 11 (61.1%) carried pathogenic Leptospira (Leptospira borgpetersenii, 7 and Leptospira interrogans, 2). Four participants showed their highest titer against an isolate obtained from a rodent (serogroup Ballum). Increasing household distance to the canal that runs through the community was associated with decreased risk of infection (odds ratio = 0.934 per 10-meter increase; 95% confidence interval, .952-.992). There are high levels of Leptospira exposure in an urban setting in Puerto Rico, for which rodents may be an important reservoir for transmission. Our findings indicate that prevention should focus on mitigating risk posed by infrastructure deficiencies such as the canal.
Risk factors for infection with chikungunya and Zika viruses in southern Puerto Rico: A community-based cross-sectional seroprevalence survey
Chikungunya virus (CHIKV) caused a large outbreak in Puerto Rico in 2014, followed by a Zika virus (ZIKV) outbreak in 2016. Communities Organized for the Prevention of Arboviruses (COPA) is a cohort study in southern Puerto Rico, initiated in 2018 to measure arboviral disease risk and provide a platform to evaluate interventions. To identify risk factors for infection, we assessed prevalence of previous CHIKV infection and recent ZIKV and DENV infection in a cross-sectional study among COPA participants. Participants aged 1–50 years (y) were recruited from randomly selected households in study clusters. Each participant completed an interview and provided a blood specimen, which was tested by anti-CHIKV IgG ELISA assay and anti-ZIKV and anti-DENV IgM MAC-ELISA assays. We assessed individual, household, and community factors associated with a positive result for CHIKV or ZIKV after adjusting for confounders. During 2018–2019, 4,090 participants were enrolled; 61% were female and median age was 28y (interquartile range [IQR]: 16–41). Among 4,035 participants tested for CHIKV, 1,268 (31.4%) had evidence of previous infection. CHIKV infection prevalence was lower among children 1–10 years old compared to people 11 and older (adjusted odds ratio [aOR] 2.30; 95% CI 1.71–3.08). Lower CHIKV infection prevalence was associated with home screens (aOR 0.51; 95% CI 0.42–0.61) and air conditioning (aOR 0.64; 95% CI 0.54–0.77). CHIKV infection prevalence also varied by study cluster of residence and insurance type. Few participants (16; 0.4%) had evidence of recent DENV infection by IgM. Among 4,035 participants tested for ZIKV, 651 (16%) had evidence of recent infection. Infection prevalence increased with older age, from 7% among 1–10y olds up to 19% among 41–50y olds (aOR 3.23; 95% CI 2.16–4.84). Males had an increased risk of Zika infection prevalence compared with females (aOR 1.31; 95% CI 1.09–1.57). ZIKV infection prevalence also decreased with the presence of home screens (aOR 0.66; 95% CI 0.54–0.82) and air conditioning (aOR 0.69; 95% CI 0.57–0.84). Similar infection patterns were observed for recent ZIKV infection prevalence and previous CHIKV infection prevalence by age, and the presence of screens and air conditioners in the home decreased infection risk from both viruses by as much as 50%.
Epidemiological, temporal, and geographic trends of leptospirosis in the United States, 2014–2020
Leptospirosis, caused by pathogenic Leptospira spp., is one of the most widespread zoonotic diseases globally. In 2014, leptospirosis was reinstated as a nationally notifiable condition due to evidence of increasing incidence and public health importance. We describe the epidemiological, temporal, and geographic trends of leptospirosis in the United States since reinstatement. Analysis included confirmed and probable leptospirosis cases from jurisdictions reporting ≥ 1 case between 2014-2020. Analyzed data included reportable case surveillance and voluntarily submitted supplemental data. Between 2014-2020, CDC received 1,053 case reports from 34 jurisdictions. The national incidence rate was 0.48 cases per 100,000 population. Since 2014, leptospirosis cases have been increasing, with an average annual gain of 13 cases (R2 = 0.69). Cases increased in summer, peaking in early fall, corresponding with warmer weather and hurricane season. Among cases with outcome data, 85% (n = 606/709) were hospitalized and 10% (n = 74) died. Seventy-seven percent of cases (n = 623) reported contact with animals or their bodily fluids while 71% (n = 578) of cases reported contact with freshwater or mud. More cases reported avocational activities (n = 413, [52%]) as the source of their animal or environmental exposure(s) than recreational or occupational activities (n = 203, [25%] vs n = 163, [20%], respectively). Only 13% of cases reported any international travel in the 30 days prior to symptom onset. An increasing number of leptospirosis cases in the U.S. are being reported, mostly from domestic sources of infection. Changing epidemiological trends away from occupational exposures to avocational or recreational activities highlights the need for interventions mitigating these exposure risks. A high percentage of cases were hospitalized and died emphasizing the need to educate healthcare providers, public health professionals, and the public about early identification and treatment for leptospirosis to improve patient outcomes.
Contact Investigation of Melioidosis Cases Reveals Regional Endemicity in Puerto Rico
Background. Melioidosis results from infection with Burkholderia pseudomallei and is associated with case-fatality rates up to 40%. Early diagnosis and treatment with appropriate antimicrobials can improve survival rates. Fatal and nonfatal melioidosis cases were identified in Puerto Rico in 2010 and 2012, respectively, which prompted contact investigations to identify risk factors for infection and evaluate endemicity. Methods. Questionnaires were administered and serum specimens were collected from coworkers, neighborhood contacts within 250 m of both patients' residences, and injection drug user (IDU) contacts of the 2012 patient. Serum specimens were tested for evidence of prior exposure to B. pseudomallei by indirect hemagglutination assay. Neighborhood seropositivity results guided soil sampling to isolate B. pseudomallei. Results. Serum specimens were collected from contacts of the 2010 (n = 51) and 2012 (n = 60) patients, respectively. No coworkers had detectable anti–B. pseudomallei antibody, whereas seropositive results among neighborhood contacts was 5% (n = 2) for the 2010 patient and 23% (n = 12) for the 2012 patient, as well as 2 of 3 IDU contacts for the 2012 case. Factors significantly associated with seropositivity were having skin wounds, sores, or ulcers (odds ratio [OR], 4.6; 95% confidence interval [CI], 1.2–17.8) and IDU (OR, 18.0; 95% CI, 1.6–194.0). Burkholderia pseudomallei was isolated from soil collected in the neighborhood of the 2012 patient. Conclusions. Taken together, isolation of B. pseudomallei from a soil sample and high seropositivity among patient contacts suggest at least regional endemicity of melioidosis in Puerto Rico. Increased awareness of melioidosis is needed to enable early case identification and early initiation of appropriate antimicrobial therapy.
Burkholderia pseudomallei, the causative agent of melioidosis, is rare but ecologically established and widely dispersed in the environment in Puerto Rico
Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. The global burden and distribution of melioidosis is poorly understood, including in the Caribbean. B. pseudomallei was previously isolated from humans and soil in eastern Puerto Rico but the abundance and distribution of B. pseudomallei in Puerto Rico as a whole has not been thoroughly investigated. We collected 600 environmental samples (500 soil and 100 water) from 60 sites around Puerto Rico. We identified B. pseudomallei by isolating it via culturing and/or using PCR to detect its DNA within complex DNA extracts. Only three adjacent soil samples from one site were positive for B. pseudomallei with PCR; we obtained 55 isolates from two of these samples. The 55 B. pseudomallei isolates exhibited fine-scale variation in the core genome and contained four novel genomic islands. Phylogenetic analyses grouped Puerto Rico B. pseudomallei isolates into a monophyletic clade containing other Caribbean isolates, which was nested inside a larger clade containing all isolates from Central/South America. Other Burkholderia species were commonly observed in Puerto Rico; we cultured 129 isolates from multiple soil and water samples collected at numerous sites around Puerto Rico, including representatives of B. anthina, B. cenocepacia, B. cepacia, B. contaminans, B. glumae, B. seminalis, B. stagnalis, B. ubonensis, and several unidentified novel Burkholderia spp. B. pseudomallei was only detected in three soil samples collected at one site in north central Puerto Rico with only two of those samples yielding isolates. All previous human and environmental B. pseudomallei isolates were obtained from eastern Puerto Rico. These findings suggest B. pseudomallei is ecologically established and widely dispersed in the environment in Puerto Rico but rare. Phylogeographic patterns suggest the source of B. pseudomallei populations in Puerto Rico and elsewhere in the Caribbean may have been Central or South America.