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Over 290 million people are infected by schistosomes worldwide. Schistosomiasis control efforts focus on mass drug treatment with praziquantel (PZQ), a drug that kills the adult worm of all Schistosoma species. Nonetheless, re-infections have continued to be detected in endemic areas with individuals living in the same area presenting with varying infection intensities. Our objective was to characterize the transcriptome profiles in peripheral blood of children between 10–15 years with varying intensities of Schistosoma mansoni infection living along the Albert Nile in Uganda. RNA extracted from peripheral blood collected from 44 S. mansoni infected (34 high and 10 low by circulating anodic antigen [CAA] level) and 20 uninfected children was sequenced using Illumina NovaSeq S4 and the reads aligned to the GRCh38 human genome. Differential gene expression analysis was done using DESeq2. Principal component analysis revealed clustering of gene expression by gender when S. mansoni infected children were compared with uninfected children. In addition, we identified 14 DEGs between S. mansoni infected and uninfected individuals, 56 DEGs between children with high infection intensity and uninfected individuals, 33 DEGs between those with high infection intensity and low infection intensity and no DEGs between those with low infection and uninfected individuals. We also observed upregulation and downregulation of some DEGs that are associated with fibrosis and its regulation. These data suggest expression of fibrosis associated genes as well as genes that regulate fibrosis in S. mansoni infection. The relatively few significant DEGS observed in children with schistosomiasis suggests that chronic S. mansoni infection is a stealth infection that does not stimulate a strong immune response. Author summary: Schistosomiasis is a neglected tropical disease transmitted via an intermediate snail host through contact with contaminated fresh water. Even with routine Mass Drug Administration for treatment of the infection, re-infections are still common and variations in infection intensity and pathology are still observed in individuals in the same location. These may be due to differences in individuals' response to S. mansoni infection. In this study, we used RNAseq to identify differentially expressed genes associated with S. mansoni infection in children between 10–15 years. We conducted comparisons between phenotypes including infection intensities measured by circulating anodic antigen, wasting by body mass index and stunting by height-for-age Z-score. Our data showed very low numbers of significantly differentially expressed genes in all comparisons. Some of the few differentially expressed genes that were observed were associated with fibrosis which is the cause of pathology in humans and has been observed in late stages of S. mansoni infection in murine studies. [ABSTRACT FROM AUTHOR]

Introduction: rickettsioses are emerging zoonotic febrile illnesses transmitted to humans by ticks, fleas, lice, and mites. Q-fever, Spotted fever group (SFG), Typhus group (TG) rickettsia and Scrub typhus (STG) have been reported with varying prevalence across East Africa. However, little is known about the burden of exposure in Uganda. The aim of this study was to determine the seroprevalence and associated risk factors of rickettsial diseases in Uganda. Methods: a total of 460 archived serum samples collected from patients with fever of unknown origin after screening across five hospital-based sentinel sites were analysed. The samples were collected during 18-month period of active surveillance for acute febrile illnesses, from January 2018 through June 2019. We performed IgM ELISA tests on the 460 sera for SFG and TG rickettsia, IgM IFA for STG and Phase 2 IgG ELISA for Q-fever. We also assessed risk factors associated with the serostatus. Results: the population comprised predominantly children, had balanced gender proportions, with 66% coming from rural areas. The overall seroprevalence of SFG rickettsiosis was 6.3%; however, 11.5% and 10.8% prevalence rates were observed in Gulu and Bwera hospitals respectively. This was higher than the 3.7% observed in the capital city Kampala, although the differences were not statistically significant (Fisher's exact = 0.489). Overall seropositivity of Q-fever was 7.6%, although Bwera Hospital had the highest rate (12.5%) and Mulago had the lowest rate (2%). The differences were not considered statistically significant (Fishers exact= 0.075). Increasing age (OR-adjusted=1.4, 95%CI=1.0-1.9, p=0.026) and rural background (OR-adjusted=2.6, 95%CI=1.6- 6.4, p=0.037) were both significantly associated with seropositivity for Q-fever, while only increasing age had higher odds for seropositivity for SFG rickettsia (OR-adjusted= 1.9, 95% CI= 1.4-2.6, p<0.001). One serum sample of a 10-month-old male from Bwera hospital was reactive to both SFG and Q-fever antibodies. We found four sera reactive cases to typhus group IgM and another four reactive to Orientia spp. IgM. However, we were not able to determine associating factors due to low seropositivity rates. Conclusion: here, we report for the first time the seroprevalence of Q-fever, SFG and STG in febrile patients in Uganda. This report also provides the second study in over five decades since the earliest report of TG rickettsia. Testing for these pathogens in patients with acute febrile illness with unknown etiology may hold value, however more studies are required to provide information on disease ecology, risk factors, and transmission dynamics of these pathogens in Uganda. [ABSTRACT FROM AUTHOR]

The article presents a study that develops four new microsatellite markers for Trypanosoma vivax from Ugandan cattle and goats. The microsatellites were chosen because they enable researchers to study the parasites at the nuclear DNA. Descriptions of the age, sex and number of cattle and goats used in the study and the blood sampling method used are provided. Information about the identified CA, GTA, CACT and TTA microsatellite markers, and explanation that there is no cross amplification with subtypes T. congolense or T. brucei are included.

Domestic dogs ( Canis lupus familiaris ) live with humans, frequently contact other animals and may serve as intermediary hosts for the transmission of viruses. Free-roaming dogs, which account for over 70% of the world's domestic dog population, may pose a particularly high risk in this regard. We conducted an epidemiological study of dog viromes in three locations in Uganda, representing low, medium and high rates of contact with wildlife, ranging from dogs owned specifically for traditional hunting in a biodiversity and disease 'hotspot' to pets in an affluent suburb. We quantified rates of contact between dogs and wildlife through owner interviews and conducted canine veterinary health assessments. We then applied broad-spectrum viral metagenomics to blood plasma samples, from which we identified 46 viruses, 44 of which were previously undescribed, in three viral families, Sedoreoviridae , Parvoviridae and Anelloviridae . All 46 viruses (100 %) occurred in the high-contact population of dogs compared to 63 % and 39 % in the medium- and low-contact populations, respectively. Viral prevalence ranged from 2.1 % to 92.0 % among viruses and was highest, on average, in the high-contact population (22.3 %), followed by the medium-contact (12.3 %) and low-contact (4.8 %) populations. Viral richness (number of viruses per dog) ranged from 0 to 27 and was markedly higher, on average, in the high-contact population (10.2) than in the medium-contact (5.7) or low-contact (2.3) populations. Viral richness was strongly positively correlated with the number of times per year that a dog was fed wildlife and negatively correlated with the body condition score, body temperature and packed cell volume. Viral abundance (cumulative normalized metagenomic read density) varied 124-fold among dogs and was, on average, 4.1-fold higher and 2.4-fold higher in the high-contact population of dogs than in the low-contact or medium-contact populations, respectively. Viral abundance was also strongly positively correlated with the number of times per year that a dog was fed wildlife, negatively correlated with packed cell volume and positively correlated with white blood cell count. These trends were driven by nine viruses in the family Anelloviridae , genus Thetatorquevirus , and by one novel virus in the family Sedoreoviridae , genus Orbivirus . The genus Orbivirus contains zoonotic viruses and viruses that dogs can acquire through ingestion of infected meat. Overall, our findings show that viral prevalence, richness and abundance increased across a gradient of contact between dogs and wildlife and that the health status of the dog modified viral infection. Other ecological, geographic and social factors may also have contributed to these trends. Our finding of a novel orbivirus in dogs with high wildlife contact supports the idea that free-roaming dogs may serve as intermediary hosts for viruses of medical importance to humans and other animals.