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Background Schistosomiasis is known to induce inflammatory immune responses. C-reactive protein (CRP), resistin and P-selectin are serological inflammatory markers that rise during the acute stages of infection. Here, we propose such inflammatory biomarkers have a potential for use in urogenital schistosomiasis diagnostic screening for exposure and infection in preschool-aged children. Methods As part of a larger study on urogenital schistosomiasis, 299 preschool children aged 1–5 years were included in this cross-sectional study. Parasitological diagnosis was conducted using urine filtration for Schistosoma haemtobium infection, and Kato Katz for S. mansoni infection. Serum levels of P-selectin, resistin, CRP, and antibodies against S. haematobium cercarial antigen preparation (CAP) and soluble worm antigen preparation (SWAP) were measured by ELISA. Results Of the 299 participants, 14% were egg positive for S. haematobium. Serology showed 46 and 9% of the participants to have been exposed to S. haematobium cercarial antigens and adult worm antigens, respectively. Levels of P-selectin were significantly higher in participants infected with S. haematobium (egg-positive) than in uninfected participants (p = 0.001). Levels of P-selectin were also higher in those exposed to cercarial antigen than in unexposed participants (p = 0.019). There was a positive correlation between P-selectin and infection intensity (r = 0.172; p = 0.002), as well as with IgM responses to CAP and SWAP (r = 0.183; p = 0.001); (r = 0.333; p r = 0.133; p = 0.029) while resistin correlated with IgM responses to CAP and SWAP (r = 0.127; p = 0.016); (r = 0.197; p = 0.0004). CRP levels were higher in those exposed to cercarial and adult worm antigens than unexposed participants (p = 0.035); (p = 0.002) respectively, while resistin was higher in participants exposed to cercarial antigen than unexposed participants (p = 0.024). Conclusion In this preschool population, P-selectin is significantly associated with urogenital schistosome infection and intensity; hence a potential biomarker for infection diagnosis and disease monitoring. The inflammatory biomarkers (P-selectin, Resistin and CRP) were significantly higher in participants exposed to cercarial antigens than unexposed individuals indicating an underlying inflammatory environment.

Countries of the World Health Organization (WHO) African Region have experienced a wide range of coronavirus disease 2019 (COVID-19) epidemics. This study aimed to identify predictors of the timing of the first COVID-19 case and the per capita mortality in WHO African Region countries during the first and second pandemic waves and to test for associations with the preparedness of health systems and government pandemic responses. Using a region-wide, country-based observational study, we found that the first case was detected earlier in countries with more urban populations, higher international connectivity and greater COVID-19 test capacity but later in island nations. Predictors of a high first wave per capita mortality rate included a more urban population, higher pre-pandemic international connectivity and a higher prevalence of HIV. Countries rated as better prepared and having more resilient health systems were worst affected by the disease, the imposition of restrictions or both, making any benefit of more stringent countermeasures difficult to detect. Predictors for the second wave were similar to the first. Second wave per capita mortality could be predicted from that of the first wave. The COVID-19 pandemic highlights unanticipated vulnerabilities to infectious disease in Africa that should be taken into account in future pandemic preparedness planning., A new study from the WHO African Region identifies features of countries that predict timing of the first case and the per capita mortality rate for the first and second waves of the COVID-19 epidemics.

Background: WHO African Region countries have experienced very different COVID-19 epidemics. This study aimed to identify predictors for the timing of the first COVID-19 case and the per capita mortality rate during the first and second pandemic wave in the region, and to test for any impact of countermeasures. Methods: We performed a region-wide, country-based observational study. Data on COVID-19 cases and deaths for all 47 countries in the WHO African Region were obtained from the WHO COVID-19 Dashboard. A set of predictors classified to nine categories were collected and used as explanatory variables. We applied Cox proportional hazards regression models, generalized linear mixed models and multinomial logistic regression models as appropriate. Findings: Predictors for an earlier first case were a more urban population, high volume of international air travel and more land borders, and better COVID-19 test capacity. Predictors for a high per capita mortality rate during the first wave were a more urban population, more pre-pandemic international air travel and higher prevalence of HIV. The stringency and timing of government restrictions on behaviour were not associated with a lower per capita mortality rate in the first wave. A more urban population and a higher infectious disease resilience score were associated with more stringent restrictions and/or a higher per capita mortality rate in the first wave. The predictor set for the second wave was similar, and first wave per capita mortality predicted that in the second wave. These results were not altered when measures of national testing effort were included in the models. Interpretation: COVID-19 in Africa arrived earlier and caused greater mortality in countries with more international travel and a more urban population. Mortality was exacerbated by high HIV prevalence; it is not clear whether this is a direct or indirect effect. Countries that were better prepared and judged to have more resilient health systems were worst affected, both by the disease and by the imposition of restrictions. The COVID-19 pandemic highlights unanticipated vulnerabilities to infectious disease in Africa. Funding Statement: National Institute for Health Research, Darwin Trust of Edinburgh Declaration of Interests: The authors disclose no conflicts of interest.

Helminth parasites have been shown to have systemic effects in the host. Using shotgun metagenomic sequencing, we characterise the gut microbiome and resistome of 113 Zimbabwean preschool-aged children (1–5 years). We test the hypothesis that infection with the human helminth parasite, Schistosoma haematobium, is associated with changes in gut microbial and antimicrobial resistance gene abundance/diversity. Here, we show that bacteria phyla Bacteroidetes, Firmicutes, Proteobacteria, and fungi phyla Ascomycota, Microsporidia, Zoopagomycota dominate the microbiome. The abundance of Proteobacteria, Ascomycota, and Basidiomycota differ between schistosome-infected versus uninfected children. Specifically, infection is associated with increases in Pseudomonas, Stenotrophomonas, Derxia, Thalassospira, Aspergillus, Tricholoma, and Periglandula, with a decrease in Azospirillum. We find 262 AMR genes, from 12 functional drug classes, but no association with individual-specific data. To our knowledge, we describe a novel metagenomic dataset of Zimbabwean preschool-aged children, indicating an association between urogenital schistosome infection and changes in the gut microbiome., Osakunor et al. show that infection of Zimbabwean preschool-aged children with Schistosoma haematobium correlates with abundance changes in Pseudomonas, Stenotrophomonas, Derxia, Thalassospira, Aspergillus, Tricholoma, Periglandula, and Azospirillum. This study provides a microbiome and resistome dataset of African preschool-aged children.

Background Plasmodium vivax infection is rising in sub-Saharan Africa, where Plasmodium falciparum is responsible for more than 90% of malaria cases. While P. vivax is identified as a major cause of severe and cerebral malaria in South east Asia, the Pacific and South America, most of the severe and cerebral cases in Africa were attributed to P. falciparum. Cases of severe malaria due to P. vivax are emerging in Africa. A few severe P. vivax cases were reported in Eastern Sudan and they were underestimated due to the lack of accurate diagnosis, low parasitaemia and seldom use of rapid diagnostic tests (RDTs). Case presentation A 60-year-old Sudanese male presented to the Al Kuwaiti hospital in the Sudan capital Khartoum. On admission, the patient was complaining of fever (measured temperature was 38 °C), sweating, chills, vomiting and confusion in the past 2 days prior to his admission. He rapidly deteriorated into a coma state within 48 h of the admission, with significant neck stiffness. He was admitted to the intensive care unit and was suspected of meningitis. Lumbar puncture was not performed since the patient was suffering from spinal cord disc. Brain CT scan was unremarkable. Several biochemical, haematological tests, and blood film for malaria were performed. The results of the laboratory tests were within the normal range except of mild elevation of the total white blood cell count and a significant decrease in the platelets count. Malaria parasites were seen in the blood film with high parasitaemia (quantified as 3 +++). The patient was diagnosed as P. vivax cerebral malaria based on the positive blood film and the amplification of P. vivax specific 499 bp amplicon using Plasmodium multi-species multiplex Polymerase Chain Reaction (PCR). The patient was treated with quinine 10 mg/kg body weight for 10 days followed by primaquine 15 mg/days PO for 2 weeks. The symptoms subsided within 48 h and the patients was cured and released from the hospital. Conclusions Plasmodium vivax is an emerging cause of cerebral malaria in adults in Sudan and should be considered in the differential diagnosis of cerebral malaria for proper management of patients.

Praziquantel (PZQ) is an anthelminthic human and veterinary drug used to treat trematode and cestode worms. Changes in immune responses have been demonstrated in humans following curative PZQ treatment of schistosome infections. These changes have been attributed to the removal of immunosupressive worms and immune responses to parasite antigens exposed from dying worms. To date, there has been no study investigating the potential direct effect of PZQ on the host immune cells. Herein, we analyzed the effect of PZQ on human CD4+ T cells classically costimulated by CD3/CD28 or costimulated by the complement regulator CD46 to induce Type 1 regulatory T cells (Tr1). Our results show that PZQ enhanced T cell proliferation, increased secretion of IL-17 and IL-10 but had no effect on secretion of GM-CSF or IFNγ. Moreover, PZQ increased the co-expression of CD49b and LAG-3, a hallmark of Tr1 cells, suggesting increased Tr1 differentiation. Indeed, supernatants from PZQ-treated cells were able to decrease bystander T cell activation, and this was partly reduced when blocking IL-10. Hence, our study demonstrates that PZQ directly modulates human T cell activation and promotes Tr1 differentiation, suggesting that PZQ may have immunomodulatory functions in parasite-unrelated human inflammatory diseases. This article is protected by copyright. All rights reserved.