Multi-host Bartonella parasites display covert host-specificity even when transmitted by generalist vectors.

Many parasites infect multiple sympatric host species and there is a general assumption that parasite transmission between co-occurring host species is commonplace. Such between-species transmission could be key to parasite persistence within a disease reservoir and is consequently an emerging focus for disease control. However, while a growing body of theory indicates the potential importance of between-species transmission for parasite persistence, conclusive empirical evidence from natural communities is lacking, and the assumption that between-species transmission is inevitable may therefore be wrong. We investigated the occurrence of between-species transmission in a well-studied multi-host parasite system. We identified the flea-borne Bartonella parasites infecting sympatric populations of Apodemus sylvaticus (Linneaus, 1978) (wood mice) and Myodes glareolus (Schreber, 1780) (bank voles) in the UK and confirmed that several Bartonella species infect both rodent species. However, counter to previous knowledge, genetic characterisation of these parasites revealed covert host-specificity, where each host species is associated with a distinct assemblage of genetic variants, indicating that between-species transmission is rare. Limited between-species transmission could result from rare encounters between one host species and the parasites infecting another and/or host-parasite incompatibility. We investigated the occurrence of such encounter and compatibility barriers by identifying the flea species associated with each rodent host, and the Bartonella variants carried by individual fleas. We found that the majority of fleas were host-generalists but the assemblage of Bartonella variants in fleas tended to reflect the assemblage of Bartonella variants in the host species they were collected from, thus providing evidence of encounter barriers mediated by limited between-species flea transfer. However, we also found several fleas that were carrying variants never found in the host species from which they were collected, indicating some degree of host-pathogen incompatibility when barriers to encounter are overcome. Overall, these findings challenge our default perceptions of multi-host parasite persistence, as they show that despite considerable overlaps in host species ecology, separate populations of the same parasite species may circulate and persist independently in different sympatric host species. This questions our fundamental understanding of endemic transmission dynamics and the control of infection within natural reservoir communities. This article is protected by copyright. All rights reserved

Defining schistosomiasis hotspots based on literature and shareholder interviews

The World Health Organization (WHO) recently proposed a new operational definition which designates communities with ≥10% prevalence of Schistosoma spp. infection as a persistent hotspot, when, after at least two rounds of high-coverage annual preventive chemotherapy, there is a lack of appropriate reduction. However, inconsistencies and challenges from both biological and operational perspectives remain, making the prescriptive use of this definition difficult. Here, we present a comprehensive analysis of the use of the term 'hotspot' across schistosomiasis research over time, including both literature searches and opinions from a range of stakeholders, to assess the utility and generalisability of the new WHO definition of a persistent hotspot. Importantly, we propose an updated definition based on our analyses

Selective serotonin reuptake inhibitor use and mortality, postoperative complications, and quality of care in hip fracture patients: a Danish nationwide cohort study

PURPOSE: To examine the association between selective serotonin reuptake inhibitor (SSRI) use and mortality, postoperative complications, and quality of in-hospital care in hip fracture patients. PATIENTS AND METHODS: The study was a nationwide cohort study based on individual-level linked, prospectively collected data from Danish population-based national registries covering all hospitals in Denmark. The health care system in Denmark is tax-funded, and all citizens have equal access to health care services. We included patients with first-time hospitalization due to hip fracture undergoing surgery from 2006–2016. We estimated the risk of 30-day mortality, any unplanned readmission, any reoperation, specific postoperative complications including cardiovascular events and major bleeding, and quality of in-hospital care using Cox and Poisson regression analyses comparing current and former SSRI users with non-users. RESULTS: In 68,487 hip fracture patients, 13,272 (19%) were current SSRI users, 2,777 (4%) were former SSRI users, and 52,438 (77%) were SSRI non-users. The 30-day mortality risk was 13% in current SSRI users (HR 1.16, 1.10–1.21) and 12% in former (HR 1.15, 1.04–1.27) compared with 10% in non-users. The HR for any unplanned readmission was 1.11 (1.02–1.20) in current and 1.13 (1.01–1.27) in former SSRI users and for any reoperation 1.21 (1.11–1.31) in current and 1.04 (0.84–1.28) in former SSRI users compared with non-users. The risk of venous thromboembolism, myocardial infarction, stroke, and bleeding were similar irrespective of SSRI use. No association between current and former SSRI use and quality of in-hospital care was found. CONCLUSION: In patients undergoing hip fracture surgery, 30-day mortality and overall readmission risk were elevated in both current and former SSRI users compared with non-users. Those currently using SSRI had a 26% increased reoperation risk compared with non-users. However, SSRI use was not associated with increased risk of other postoperative complications and lower quality of in-hospital care. A limitation of this study was the inability to control for potential confounding of social deprivation

The impact of albendazole treatment on the incidence of viral- and bacterial-induced diarrhea in school children in southern Vietnam: study protocol for a randomized controlled trial

Anthelmintics are one of the more commonly available classes of drugs to treat infections by parasitic helminths (especially nematodes) in the human intestinal tract. As a result of their cost-effectiveness, mass school-based deworming programs are becoming routine practice in developing countries. However, experimental and clinical evidence suggests that anthelmintic treatments may increase susceptibility to other gastrointestinal infections caused by bacteria, viruses, or protozoa. Hypothesizing that anthelmintics may increase diarrheal infections in treated children, we aim to evaluate the impact of anthelmintics on the incidence of diarrheal disease caused by viral and bacterial pathogens in school children in southern Vietnam.This is a randomized, double-blinded, placebo-controlled trial to investigate the effects of albendazole treatment versus placebo on the incidence of viral- and bacterial-induced diarrhea in 350 helminth-infected and 350 helminth-uninfected Vietnamese school children aged 6-15 years. Four hundred milligrams of albendazole, or placebo treatment will be administered once every 3 months for 12 months. At the end of 12 months, all participants will receive albendazole treatment. The primary endpoint of this study is the incidence of diarrheal disease assessed by 12 months of weekly active and passive case surveillance. Secondary endpoints include the prevalence and intensities of helminth, viral, and bacterial infections, alterations in host immunity and the gut microbiota with helminth and pathogen clearance, changes in mean z scores of body weight indices over time, and the number and severity of adverse events.In order to reduce helminth burdens, anthelmintics are being routinely administered to children in developing countries. However, the effects of anthelmintic treatment on susceptibility to other diseases, including diarrheal pathogens, remain unknown. It is important to monitor for unintended consequences of drug treatments in co-infected populations. In this trial, we will examine how anthelmintic treatment impacts host susceptibility to diarrheal infections, with the aim of informing deworming programs of any indirect effects of mass anthelmintic administrations on co-infecting enteric pathogens.ClinicalTrials.gov: NCT02597556 . Registered on 3 November 2015

ECONOMIC VALUES IN DAIRY CATTLE BREEDING, WITH SPECIAL REFERENCE TO FUNCTIONAL TRAITS

Genetski i socio-ekonomski ujednačena selekcija proizvodnih (mlijeko i govedina) i finkcionalnih osobina (zdravlje, plodnost,djelotvornost iskorištavanja hrane i mliječnost) u mliječnog goveda traži ispravne ekonomske vrijednosti. lspravne relativne razine ekonomskih vrijednosti osobina daju optimalne razine genetskog poboljšanja u skladu s budućim uvjetima proizvodnje; ispravne apsolutne razine važne su za točno izračunavanje ekonomske dobiti uzgojnih programa. Izvođenje ekonomske vrijednosti zahtijeva dobru ekonomsku osnovu, pravilnu metodologiju u odnosu na modele, ukljudujući fiziološko oblikovanje proizvodnje životinja, ekonomičnosti farme i socijalnih aspekata i odgovarajuće pretpostavke uvjetra buduće proizvodnje. Područje definicije cilja uzgoja zanimljivo je osobito zbog toga što se znanje o oblikovanju poboljšava a nesigurni uvjeti buduće proizvodnje neprestano mijenjaju. Osim toga, iako se istraživanja provode već dugo vremena praktična integracija funkcionalnih osobina u ciljevima uzgoja mliječnog goveda još uvijek je veliki izazov za uzgajivače životinja. Ciljevi izvještaja ove radne grupe su: a) predstaviti definiciju skupine osobina uzgojnih ciljeva, b) raspraviti o metodologiji izvođenja ekonomskih vrijednosti, c) dati sažetak literature o ekonomskim vrijednostima funkcionalnih osobina, d) raspraviti o mogućem opravdanju razlike u definiciji uzgojnih ciljeva nekih zemalja, područja i/ili individualnih farma, i e) raspraviti o mogućim budućim tendencijama što bi mogle utjecati na uzgojne ciljeve promjenom ekonomskih vrijednosti.A genetically and socio-economically balanced selection on production (milk and beef) and functional traits (health, fertility, efficiency of feed utilisation and milkability) in dairy cattle requires correct economic values. Correct relative levels of economic values of traits give optimum levels of genetic improvement according to future production circumstances; correct absolute levels are important for an accurate calculation of economic revenues of breeding programmes. The derivation of economic values requires a good theoretical basis, proper methodology in terms of models including physiological modelling of animal production, farm economics and social aspects, and appropriate assumptions on future production circumstances. The field of breeding goal definition is of ongoing interest, especially because knowledge on modelling is improving and on uncertain future production circumstances are continuously changing. Moreover, although research has been undertaken for a long period, the practical integration of functional traits in dairy cattle breeding goals is still a major challenge for animal breeders. The aims of this working group report are: a. to present the definition of a set of breeding goal traits, b. to discuss the methodology in deriving economic values, c. to present a summary of literature on economic values of functional traits, d. to discuss a possible justification of differences in breeding goal definition for countries, regions, and/or individual farms, and e. to discuss possible future trends potentially influencing breeding goals by changing economic values

Phthalates and Perfluorooctanesulfonic Acid in Human Amniotic Fluid: Temporal Trends and Timing of Amniocentesis in Pregnancy

Background: Measures of prenatal environmental exposures are important, and amniotic fluid levels may directly reflect fetal exposures during hypothesized windows of vulnerability