GENETIC AND MORPHOLOGIC CHARACTERIZATION OF DIASCHISTORCHIS PANDUS (DIGENEA: PRONOCEPHALIDAE) TREMATODES EXTRACTED FROM HAWKSBILL TURTLES, ERETMOCHELYS IMBRICATA (TESTUDINES: CHELONIIDAE), IN GRENADA, WEST INDIES

The hawksbill turtle Eretmochelys imbricata is a critically endangered species with a worldwide distribution. Limited information is available about the naturally occurring intestinal parasites of this species and what impact these parasites may have on the health of the hawksbill turtle. Diaschistorchis pandus was identified postmortem in 5 hawksbill turtles from Grenada, West Indies, using morphologic characterization. Sanger sequencing was performed for conserved ribosomal regions (5.8S, ITS2, 28S) and the mitochondrial cytochrome c oxidase subunit 1 gene (COI). Phylogenetic analysis of the 28S rRNA gene sequence data shows D. pandus clustering with other trematodes in the family Pronocephalidae, corroborating morphological classification. No genetic sequences have been previously reported for this trematode species, which has limited the collection of objective epidemiological data about this parasite of marine turtles.

The Kidney-Associated Microbiome of Wild-Caught Artibeus spp. in Grenada, West Indies

Simple Summary

Bats are increasingly being recognized as important integrants of zoonotic disease cycles. Studying bat microbiomes could potentially contribute to the epidemiology of emerging infectious diseases in humans. Furthermore, studying the bat’s microbiome gives us the opportunity to look at the microbiome evolution in mammals. Bat microbiome studies have focused mainly on the gut microbiome, but little is known of the microbiome of the kidney, another potential source of disease transmission. Furthermore, many studies on microbiome found in the literature are based on captive animals, which usually alters the natural microbiome. Here, we analyzed kidney samples of wild-caught Artibeus spp., a fructivorous bat species from Grenada, West Indies, using metagenomics.

Abstract

Bats are capable of asymptomatically carrying a diverse number of microorganisms, including human pathogens, due to their unique immune system. Because of the close contact between bats and humans, there is a possibility for interspecies transmission and consequential disease outbreaks. Herein, high-throughput sequencing was used to determine the kidney-associated microbiome of a bat species abundant in Grenada, West Indies, Artibeus spp. Results indicate that the kidney of these bats can carry potential human pathogens. An endogenous retrovirus, Desmodus rotundus endogenous retrovirus isolate 824, phylogenetically related to betaretroviruses from rodents and New World primates, was also identified.

Preliminary Characterization of Triatomine Bug Blood Meals on the Island of Trinidad Reveals Opportunistic Feeding Behavior on Both Human and Animal Hosts

Chagas disease is a neglected tropical disease caused by infection with Trypanosoma cruzi. The parasite is endemic to the Americas, including the Caribbean, where it is vectored by triatomine bugs. Although Chagas disease is not considered a public health concern in the Caribbean islands, studies in Trinidad have found T. cruzi-seropositive humans and T. cruzi-infected triatomine bugs. However, little is known about triatomine bug host preferences in Trinidad, making it difficult to evaluate local risk of vector-borne T. cruzi transmission to humans. To investigate this question, we collected triatomine bugs in Trinidad and diagnosed each one for T. cruzi infection (microscopy and PCR). We then carried out a blood meal analysis using DNA extracted from each bug (PCR and sequencing). Fifty-five adult bugs (54 Panstrongylus geniculatus and one Rhodnius pictipes) were collected from five of 21 sample sites. All successful collection sites were residential. Forty-six out of the 55 bugs (83.6%) were infected with T. cruzi. Fifty-three blood meal hosts were successfully analyzed (one per bug), which consisted of wild birds (7% of all blood meals), wild mammals (17%), chickens (19%), and humans (57%). Of the 30 bugs with human blood meals, 26 (87%) were from bugs infected with T. cruzi. Although preliminary, our results align with previous work in which P. geniculatus in Trinidad had high levels of T. cruzi infection. Furthermore, our findings suggest that P. geniculatus moves between human and animal environments in Trinidad, feeding opportunistically on a wide range of species. Our findings highlight a critical need for further studies of Chagas disease in Trinidad in order to estimate the public health risk and implement necessary preventative and control measures.

Metagenomic analysis of Aedes aegypti and Culex quinquefasciatus mosquitoes from Grenada, West Indies

The mosquitoes Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) and Culex quinquefasciatus Say, 1823 (Diptera: Culicidae) are two major vectors of arthropod-borne pathogens in Grenada, West Indies. As conventional vector control methods present many challenges, alternatives are urgently needed. Manipulation of mosquito microbiota is emerging as a field for the development of vector control strategies. Critical to this vector control approach is knowledge of the microbiota of these mosquitoes and finding candidate microorganisms that are common to the vectors with properties that could be used in microbiota modification studies. Results showed that bacteria genera including Asaia, Escherichia, Pantoea, Pseudomonas, and Serratia are common to both major arboviral vectors in Grenada and have previously been shown to be good candidates for transgenetic studies. Also, for the first time, the presence of Grenada mosquito rhabdovirus 1 is reported in C. quinquefasciatus.

High prevalence of Phasi Charoen-like virus from wild-caught Aedes aegypti in Grenada, W.I. as revealed by metagenomic analysis

Arboviruses cause diseases of significant global health concerns. Interactions between mosquitoes and their microbiota as well as the important role of this interaction in the mosquito's capacity to harbor and transmit pathogens have emerged as important fields of research. Aedes aegypti is one of the most abundant mosquitoes in many geographic locations, a vector capable of transmitting a number of arboviruses such as dengue and Zika. Currently, there are few studies on the metavirome of this mosquito particularly in the Americas. This study analyzes the metavirome of A. aegypti from Grenada, a Caribbean nation with tropical weather, abundant A. aegypti, and both endemic and arboviral pathogens transmitted by this mosquito. Between January and December 2018, 1152 mosquitoes were collected from six semi-rural locations near houses in St. George Parish, Grenada, by weekly trapping using BG-Sentinel traps. From these, 300 A. aegypti were selected for analysis. The metavirome was analyzed using the Illumina HiSeq 1500 for deep sequencing. The generation sequencing library construction protocol used was NuGEN Universal RNA with an average read length of 125 bp. Reads were mapped to the A. aegypti assembly. Non-mosquito reads were analyzed using the tools FastViromeExplorer. The NCBI total virus, RNA virus, and eukaryotic virus databases were used as references. The metagenomic comparison analysis showed that the most abundant virus-related reads among all databases and assemblies was Phasi Charoen-like virus. The Phasi Charoen-like virus results are in agreement to other studies in America, Asia and Australia. Further studies using wild-caught mosquitoes is needed to assess the impact of this insect-specific virus on the A. aegypti lifecycle and vector capacity.

Phylogenetic relationships and diversity of bat-associated Leptospira and the histopathological evaluation of these infections in bats from Grenada, West Indies

Bats can harbor zoonotic pathogens, but their status as reservoir hosts for Leptospira bacteria is unclear. During 2015–2017, kidneys from 47 of 173 bats captured in Grenada, West Indies, tested PCR-positive for Leptospira. Sequence analysis of the Leptospira rpoB gene from 31 of the positive samples showed 87–91% similarity to known Leptospira species. Pairwise and phylogenetic analysis of sequences indicate that bats from Grenada harbor as many as eight undescribed Leptospira genotypes that are most similar to known pathogenic Leptospira, including known zoonotic serovars. Warthin-Starry staining revealed leptospiral organisms colonizing the renal tubules in 70% of the PCR-positive bats examined. Mild inflammatory lesions in liver and kidney observed in some bats were not significantly correlated with renal Leptospira PCR-positivity. Our findings suggest that Grenada bats are asymptomatically infected with novel and diverse Leptospira genotypes phylogenetically related to known pathogenic strains, supporting the hypothesis that bats may be reservoirs for zoonotic Leptospira.

Leptospirosis is a worldwide disease of humans and animals caused by pathogenic strains of Leptospira spp. These bacteria are transmitted in urine from infected and usually asymptomatic reservoir hosts. Leptospira have been detected in several species of animals in Grenada, and human cases of leptospirosis are reported annually. However, little is known about the source of infection, and while rats are the most commonly recognized reservoir host of Leptospira, there is growing evidence that bats may also be asymptomatic carriers in the wild. To examine this, we captured different species of bats in Grenada, West Indies, from 2015 to 2017, tested kidney tissue for Leptospira spp. bacteria by PCR, and performed histological examination to see whether there is any relationship between Leptospira infection and associated lesions. Our results suggest that two species of bats tested—Artibeus spp. and Glossophaga longirostris—are asymptomatically infected with several types of Leptospira bacteria that may be new to science and that are phylogenetically related to strains that are known to cause disease.

Identification of Helminth Parasites from Selar crumenophthalmus in Grenada, West Indies

HIGHLIGHTS

Helminths in Selar crumenophthalmus fish were identified by PCR. Two helminth taxa were identified: Anisakis typica and an unknown acanthocephalan. Neither taxon of helminth identified is zoonotic. To our knowledge, this is the first report of either type of helminth in fish in Grenada.

PCR-Based Bloodmeal Analysis of Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) in St. George Parish, Grenada

Blood-feeding patterns of mosquitoes affect the transmission and maintenance of arboviral diseases. In the Caribbean, Aedes aegypti (L.) and Culex quinquefasciatus Say mosquitoes are the dominant mosquito species in developed areas. However, no information is available on the bloodmeal hosts of these invasive vectors in Grenada, where arboviral pathogens such as dengue, chikungunya, and Zika viruses cause significant human suffering. To this end, Ae. aegypti and Cx. quinquefasciatus mosquitoes were investigated from five semirural locations near houses in St. George's Parish, from 2017 to 2018. Polymerase chain reaction was conducted on DNA extracted from individual blood-fed mosquitoes using vertebrate-specific cytochrome b primers. The 32 Ae. aegypti bloodmeals included humans (70%), mongooses (18%), domestic dogs (6%), a domestic cat (3%), and an unidentified bird (3%). Thirty-seven Cx. quinquefasciatus mosquitoes took bloodmeals from seven species of birds (51%), humans (27%), domestic cats (8%), iguanas (5%), a domestic dog (3%), a rat (3%), and a common opossum (3%). The high percentage of human bloodmeal hosts in our study, especially by the normally anthropophilic Ae. aegypti, is expected. The bloodmeal sources and the percentage of nonhuman bloodmeals (30%) taken by Ae. aegypti are comparable to other studies. The large range of hosts may be explained in part by the semirural nature of most local housing. Accordingly, this may contribute to an exchange of pathogens between domestic, peridomestic, and sylvatic transmission cycles.

Assessment of American College of Rheumatology quality criteria for rheumatoid arthritis in a pre-quality criteria patient cohort

OBJECTIVE

To evaluate the American College of Rheumatology (ACR) starter set of quality measures for rheumatoid arthritis (RA) in an actual patient cohort that preceded publication of the quality measures.

METHODS

We retrospectively applied the 2006 ACR quality criteria to a prospectively studied cohort of 568 patients with RA treated by 1,932 unique physicians including 255 different rheumatologists between the years 1999 and 2003. Data on performance were obtained from self-report surveys and medical record review within 12 months.

RESULTS

At least 1 joint examination was performed in 98% of patients. Patient and physician global assessments were reported for 79% and 74% of patients, respectively. A total of 85% of patients received disease-modifying antirheumatic drugs (DMARDs). DMARD adjustments were made for 50% of patients in whom increasing disease activity was noted at least once and for 64% of patients in whom increasing disease activity was noted during 2 (of 4) 3-month periods within the year. Compared with self-report surveys, medical records substantially underreported performance on quality measures.

CONCLUSION

The ACR-endorsed quality measures for RA can be assessed using available data sources. When both self-report and medical record data are used, adherence rates, designed to serve as minimum standards of care, were moderate or high for most measures. Prior to using indicators to compare quality across groups, specific strategies for operationalizing measures and for using accurate data sources to assess adherence to the measures should be defined.

Application of explicit process of care measurement to rheumatoid arthritis: Moving from evidence to practice

OBJECTIVE

To construct quality measures with measurement validity and meaning for clinicians.

METHODS

We conducted a prospective cohort study of rates of change in disease-modifying antirheumatic drug (DMARD) and/or systemic corticosteroid drug or dose for 568 patients with rheumatoid arthritis (RA) across 6,159 clinical encounters within 12 months to examine how changes in clinical specifications change adherence.

RESULTS

Rates of DMARD change were sensitive to specifications regarding the intensity of disease activity (severe or moderate), duration of specified disease activity, and length of the observation period. Over 12 months, the proportions of 377 patients with severe disease activity observed for 1-month, 2-month, and 3-month time blocks who had a change in DMARD drug or dose were 36%, 57%, and 74%, respectively. Over 12 months, a change in DMARD drug or dose was observed for 44%, 50%, and 68% of 377 patients with severe disease within 3 months, 6 months, and 12 months, respectively, of the patient meeting criteria for severe disease activity. A change in DMARD drug or dose was observed for 21%, 23%, and 34% of 149 patients with moderate disease activity within 3, 6, and 12 months, respectively, of the patient meeting criteria for moderate disease activity.

CONCLUSION

Rates of pharmacologic interventions for patients with moderate and severe RA disease activity vary substantially by intensity and duration of disease activity and by duration of period for observing change. Lack of precision in explicit process criteria could substantially mislead comparisons of quality of care across comparison groups.

Second renal transplantations. Ethical issues clarified by outcome; outcome enhanced by a reliable crossmatch

OBJECTIVE

To determine whether the appropriate use of scarce donor resources has been accomplished by renal retransplantation by reviewing the initial and long-term outcomes of second-renal transplant recipients at the Massachusetts General Hospital, Boston.

PATIENTS AND RESULTS

With a mean follow-up of nearly 5 years following transplantation, 54 (68%) of 80 second-transplant recipients had functioning allografts (allograft failure was defined by patient death or a return to dialysis). Rejection was the most common cause of failure (14 [54%] of 26 patients). The 1-, 3-, and 5-year actuarial allograft survival rates were 86%, 78%, and 69%, respectively, which were not significantly different from the survival rates of primary allografts at this center. These results support the continued approach of providing both cadaver-donor and living-donor renal allografts for recipients whose primary renal allograft has failed. The antiglobulin crossmatch may have contributed to the successful outcome by accurately determining compatibility and by averting early rejection failures.

CONCLUSIONS

Health care policy reviewers should clearly distinguish the prospects for successful second renal transplants from the outcomes of extrarenal retransplantation. Moreover, because excellent second-renal allograft survival is attainable and comparable to primary-renal allograft survival and because the costs are comparable, restricting suitable patients to subsequent lifelong dialysis becomes unethical.