First report of Rice yellow mottle virus on rice in Burundi

International audienceFirst Report of Rice yellow mottle virus on Rice in Burund

First Report of Rice yellow mottle virus in rice in Malawi

International audienceFirst report of Rice yellow mottle virus in rice in Malaw

Fusarium and Sarocladium Species Associated with Rice Sheath Rot Disease in Sub-Saharan Africa

Sarocladium and Fusarium species are commonly identified as causal agents of rice sheath rot disease worldwide. However, limited knowledge exists about their genetic, pathogenic, and toxigenic diversity in sub-Saharan African (SSA) countries, where an increasing incidence of this disease has been observed. In this study, seventy fungal isolates were obtained from rice plants displaying disease symptoms in rice research programs and farmer fields in Mali, Nigeria, and Rwanda. Thus, an extensive comparative analysis was conducted to assess their genetic, pathogenic, and toxigenic diversity. The Fusarium spp. were characterized using the translation elongation factor (EF-1a) region, while a concatenation of Internal Transcribed Spacer (ITS) and Actin-encoding regions were used to resolve Sarocladium species. Phylogenetic analysis revealed four Fusarium species complexes. The dominant complex in Nigeria was the Fusarium incarnatum-equiseti species complex (FIESC), comprising F. hainanense, F. sulawesiense, F. pernambucatum, and F. tanahbumbuense, while F. incarnatum was found in Rwanda. The Fusarium fujikuroi species complex (FFSC) was predominant in Rwanda and Mali, with species such as F. andiyazi, F. madaense, and F. casha in Rwanda and F. annulatum and F. nygamai in Mali. F. marum was found in Nigeria. Furthermore, Fusarium oxysporum species complex (FOSC) members, F. callistephi and F. triseptatum, were found in Rwanda and Mali, respectively. Two isolates of F. acasiae-mearnsii, belonging to the Fusarium sambucinum species complex (FSAMSC), were obtained in Rwanda. Isolates of Sarocladium, which were previously classified into three phylogenetic groups, were resolved into three species, which are attenuatum, oryzae, and sparsum. S. attenuatum was dominant in Rwanda, while S. oryzae and S. sparsum were found in Nigeria. Also, the susceptibility of FARO44, a rice cultivar released by Africa Rice Centre (AfricaRice), was tested against isolates from the four Fusarium species complexes and the three Sarocladium species. All isolates evaluated could induce typical sheath rot symptoms, albeit with varying disease development levels. In addition, liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to determine variation in the in vitro mycotoxins of the Fusarium species. Regional differences were observed in the in vitro mycotoxins profiling. Out of the forty-six isolates tested, nineteen were able to produce one to four mycotoxins. Notably, very high zearalenone (ZEN) production was specific to the two F. hainanense isolates from Ibadan, Nigeria, while Fusarium nygamai isolates from Mali produced high amounts of fumonisins. To the best of our knowledge, it seems that this study is the first to elucidate the genetic, pathogenic, and toxigenic diversity of Fusarium species associated with the rice sheath rot disease complex in selected countries in SSA

First evidence for the spread of East African cassava mosaic virus Uganda (EACMVUG) and the pandemic of severe cassava mosaic disease to Burundi

Cassava mosaic disease (CMD) is the most important constraint to cassava (Manihot esculenta) production in Africa. Since the 1990s, the importance of the disease has been greatly increased by the spread through East and Central Africa of a pandemic of unusually severe CMD (Legg, 1999), associated with the recombinant begomovirus, East African cassava mosaic virus– Uganda (EACMV-UG) (Zhou et al., 1997). Following reports of the spread of EACMV-UG to Rwanda (Legg et al., 2001), it became apparent that Burundi, to the south, was also threatened. A survey of cassava plantings in Burundi was therefore conducted in May/June 2003 to assess the status of CMD and to identify begomoviruses present. Fifty-three fields were sampled in 10 of the country's 16 regions and CMD-diseased leaf samples collected in each field for virus diagnosis. Assessments were made of CMD incidence, severity (using the standard 1–5 scale), infection type (either cutting or whitefly borne) and abundance of the whitefly vector, Bemisia tabaci. Viruses were diagnosed from leaf samples using both specific primer PCR (Zhou et al., 1997) and restriction digestion with EcoRV and MluI of near full-length DNA-A fragments amplified using universal begomovirus primers (Briddon & Markham, 1994). EACMV-UG, ACMV, EACMV and mixed ACMV + EACMV-UG infections were identified from 17, 34, one and three sites, respectively. EACMV-UG occurred at all sites in the north-eastern regions of Muyinga and Kirundo, was present at some sites in northern Gitega, Ngozi, Karuzi, Kayanza, Ruyigi and northern Rutana, but was not recorded from southern Gitega, southern Rutana, Muramvya or Bujumbura. The EACMV-UG-affected regions of Muyinga and Kirundo were distinct from the others in having higher CMD incidence (79 vs. 42%), a greater proportion of whitefly-borne to cutting-borne infection (1·9 vs. 0·6), more severe symptoms (4·17 vs. 3·26) and a greater abundance of B. tabaci (4·9 vs. 1·0). This data set provides clear evidence for the rapid spread of severe EACMV-UG-associated CMD in the north-eastern regions of Kirundo and Muyinga. The occurrence of EACMV-UG at sites in northern, central and eastern Burundi also suggests that similar changes in CMD epidemiology are likely to occur here in the near future. These results represent the first report of the expansion of the African CMD pandemic into Burundi

Electroencephalography and psychological assessment datasets to determine the efficacy of a low-cost, wearable neurotechnology intervention for reducing Post-Traumatic Stress Disorder symptom severity

The datasets described here comprise electroencephalography (EEG) data and psychometric data freely available on data.mendeley.com. The EEG data is available in .mat formatted files containing the EEG signal values structured in two-dimensional (2D) matrices, with channel data and trigger information in rows, and samples in columns (having a sampling rate of 250Hz). Twenty-nine female survivors of the 1994 genocide against the Tutsi in Rwanda, underwent a psychological assessment before and after an intervention aimed at reducing Post-Traumatic Stress Disorder (PTSD) symptom severity. Three measures of trauma and four measures of wellbeing were assessed using empirically validated standardised assessments. The pre- and post- intervention psychometric data were analysed using non-parametric statistical methods and the post-intervention data were further evaluated according to diagnostic assessment rules to determine clinically relevant improvements for each group. The participants were assigned to a control group (CG, n = 9), a motor-imagery group (MI, n = 10), and a neurofeedback group (NF, n = 10). Participants in the latter two groups received Brain-Computer Interface (BCI) based training as a treatment intervention over a sixteen-day period, between the pre- and post- clinical interviews. The training involved presenting feedback visually via a videogame, based on real-time analysis of the EEG recorded data during the BCI-based treatment session. Participants were asked to regulate (NF) or intentionally modulate (MI) brain activity to affect/control the game

Spatiotemporal patterns of genetic change amongst populations of cassava Bemisia tabaci whiteflies driving virus pandemics in East and Central Africa

The greatest current threat to cassava in sub-Saharan Africa, is the continued expansion of plant virus pandemics being driven by super-abundant populations of the whitefly vector, Bemisia tabaci. To track the association of putatively genetically distinct populations of B. tabaci with pandemics of cassava mosaic disease (CMD) and cassava brown streak disease (CBSD), a comprehensive region-wide analysis examined the phylogenetic relationships and population genetics of 642 B. tabaci adults sampled from cassava in six countries of East and Central Africa, between 1997 and 2010, using a mitochondrial DNA cytochrome oxidase I marker (780 bases). Eight phylogenetically distinct groups were identified, including one, designated herein as ‘East Africa 1’ (EA1), not previously described. The three most frequently occurring groups comprised >95% of all samples. Among these, the Sub-Saharan Africa 2 (SSA2) group diverged by c. 8% from two SSA1 sub-groups (SSA1-SG1 and SSA1-SG2), which themselves were 1.9% divergent. During the 14-year study period, the group associated with the CMD pandemic expansion shifted from SSA2 to SSA1-SG1. Population genetics analyses of SSA1, using Tajima's D, Fu's Fs and Rojas’ R2 statistics confirmed a temporal transition in SSA1 populations from neutrally evolving at the outset, to rapidly expanding from 2000 to 2003, then back to populations more at equilibrium after 2004. Based on available evidence, hybrid introgression appears to be the most parsimonious explanation for the switch from SSA2 to SSA1-SG1 in whitefly populations driving cassava virus pandemics in East and Central Africa

Patient characteristics, early outcomes, and implementation lessons of cervical cancer treatment services in rural Rwanda

Purpose Low- and middle-income countries account for 86% of all cervical cancer cases and 88% of cervical cancer mortality globally. Successful management of cervical cancer requires resources that are scarce in sub-Saharan Africa, especially in rural settings. Here, we describe the early clinical outcomes and implementation lessons learned from the Rwanda Ministry of Health’s first national cancer referral center, the Butaro Cancer Center of Excellence (BCCOE). We hypothesize that those patients presenting at earlier stage and receiving treatment will have higher rates of being alive. Methods The implementation of cervical cancer services included developing partnerships, clinical protocols, pathology services, and tools for monitoring and evaluation. We conducted a retrospective study of patients with cervical cancer who presented at BCCOE between July 1, 2012, and June 30, 2015. Data were collected from the electronic medical record system and by manually reviewing medical records. Descriptive, bivariable and multivariable statistical analyses were conducted to describe patient demographics, disease profiles, treatment, and clinical outcomes. Results In all, 373 patients met the study inclusion criteria. The median age was 53 years (interquartile rage, 45 to 60 years), and 98% were residents of Rwanda. Eighty-nine percent of patients had a documented disease stage: 3% were stage I, 48% were stage II, 29% were stage III, and 8% were stage IV at presentation. Fifty percent of patients were planned to be treated with a curative intent, and 54% were referred to chemoradiotherapy in Uganda. Forty percent of patients who received chemoradiotherapy were in remission. Overall, 25% were lost to follow-up. Conclusion BCCOE illustrates the feasibility and challenges of implementing effective cervical cancer treatment services in a rural setting in a low-income country