scholarly journals First report of banana bunchy top virus in banana (Musa spp.) and its eradication in Togo

Plant Disease ◽  
2021 ◽  
Author(s):  
Yao Kolombia ◽  
Taiwo Oviasuyi ◽  
Kwasi Dzola AYISAH ◽  
Ayefouni Ale Gonh-Goh ◽  
Tagba Atsu ◽  
...  

Banana (including plantain; Musa spp.) is a vegetatively propagated semi-perennial crop in fields and backyard gardens in Togo. Banana bunchy top disease (BBTD), caused by banana bunchy top virus (BBTV, genus Babuvirus) is the most economically important viral disease, infection of which causes severe stunting and production losses of 90-100% within two seasons. The virus is spread by banana aphid, Pentalonia nigronervosa, and through vegetative propagation from infected sources. BBTV occurrence was first reported in West Africa in 2011 with confirmation in Republic of Benin and in Nigeria in 2012 . A regional alliance (www.bbtvalliance.org) has been established for BBTV surveillance through frequent surveys in countries neighboring those affected, such as Togo. The surveys conducted in September 2018 in banana growing areas in Togo revealed plants with typical symptoms (severe stunting, bunchy growth with shortened petioles with chlorotic streaks and yellow leaf margins) in three banana fields. Locations were Tsévié, Préfecture de Zio, (6.44°N, 1.21028°E), Lilicope, Préfecture de Zio in Maritime region (6.56583°N, 1.18639°E), and Amoutchou, Préfecture de l’Ogou in Plateaux region (7.3775°N, 1.17472°E). Leaf samples were collected from symptomatic (N=8) and asymptomatic plants (N=30) and used for DNA extraction followed by a polymerase chain reaction (PCR) for BBTV detection to amplify ~240 bp sequence of DNA-R encoding for core replicase gene. All samples from symptomatic plants (N=8) tested positive and asymptomatic plants were negative. To ascertain virus identity the 240-bp PCR product was purified and sequenced in both directions. A BLAST search of the sequence (NCBI GenBank Acc.# MK073116) revealed 99% identity with DNA-R sequences of BBTV isolates from Africa (e.g., JQ437549-Benin, JN290301-Nigeria). Further analysis of the 240-bp nucleotide sequence with Maximum-likelihood phylogenetic analysis using MEGA-X software has grouped the BBTV isolate with sub-Saharan African sub-clade of the South Pacific group. To further confirm the virus identity, two samples from symptomatic (PCR positive) and asymptomatic (PCR negative) plants from Tsévié were tested by TAS-ELISA using BBTV ELISA reagent set (Cat. No. SRA24700-1000, Agdia, France) following the manufacturers’ protocol. Only samples from two symptomatic plants that were positive in PCR reacted positively in TAS-ELISA; asymptomatic plants were negative. BBTV was not observed in any of the 22 locations surveyed as a follow-up in banana producing areas. To our knowledge, this is the first report of BBTV infecting banana in Togo. The plants detected in the three sites were eradicated in the follow-up action implemented by the alliance team together with the Direction de la Protection des Végétaux of Togo. Follow-up surveys were conducted in the same regions in 2019 and 2020 to ensure disease-free status in these sites and other banana producing regions in Togo. Efforts have been made to raise awareness about BBTD recognition, diagnosis, and eradication. To the best of our knowledge this is the first case of rapid detection and eradication of BBTD in sub-Saharan Africa. This study illustrates the importance of regular surveillance for early detection of invasive virus threats and the value of rapid eradication to contain viruses before spread and establishment in a new territory.

Plant Disease ◽  
2021 ◽  
Author(s):  
Shimwela Mpoki ◽  
George Mahuku ◽  
Deusdedith Rugaihukamu Mbanzibwa ◽  
Geoffrey Mkamilo ◽  
Deogratius Mark ◽  
...  

Banana (including plantain; Musa spp.) is an important vegetatively propagated food staple grown as a semi-perennial crop in fields and backyard gardens in Tanzania. Banana bunchy top disease (BBTD), caused by the banana bunchy top virus (BBTV, genus Babuvirus), is the most economically important viral disease of banana, infection of which results in severe stunting and reduction in fruit production by 90-100% within two seasons. The virus is spread by the banana aphid, Pentalonia nigronervosa, and through vegetative propagation of infected sources. BBTV is an introduced virus first reported in sub-Saharan Africa (SSA) in the 1960s in the Democratic Republic of Congo. Since then, BBTV spread was confirmed in 15 countries in Central, Southern, and Western African regions but was not detected in any previous surveys in the East African sub-region. During banana pests and disease surveys conducted in December 2020 – January 2021 in Buhigwe District in the Kigoma Region of Tanzania revealed banana plants with typical BBTV symptoms (severe stunting, leaves with shortened petioles, chlorotic streaks, and yellow leaf margins) in several banana fields in Muhinda (lon. 29.78662, lat. -4.53672) and Mwayaya (lon. 29.8218, lat. -4.49203) villages. Most of the affected plantations were 5 to 15 years old. Leaf samples (N=21) from symptomatic (N=6) and asymptomatic (N=15) banana plants were collected and used for total DNA extraction and BBTV detection by polymerase chain reaction (PCR) using the primer pair BBTV-1 and BBTV-2 to amplify ~240 bp sequence of DNA-R encoding for core master replication initiator protein gene. All samples from symptomatic plants tested positive and asymptomatic plants were negative. To further confirm the virus identity, four samples, each from symptomatic (PCR positive) and asymptomatic (PCR negative) plants from Muhinda and Mwayaya villages, were tested by Triple Antibody Sandwich-Enzyme-linked Immunosorbent Assay (TAS-ELISA) using BBTV ELISA reagent set (Cat. # SRA24700-1000, Agdia, France) following the manufacturer's protocol. Samples from symptomatic plants reacted positively in TAS-ELISA, and asymptomatic plants were negative. The 240-bp PCR product of two isolates was purified, and both strands were sequenced. A BLAST search of the nucleotide sequences (NCBI GenBank Acc.# MW711671 and MW711672) revealed 99% identity with DNA-R sequences of several other BBTV isolates from Africa (Acc. No# JF755994). Further analysis of the 240-bp nucleotide sequences with Maximum-likelihood phylogenetic analysis using MEGA-X software has grouped the two BBTV sequence isolates with the SSA sub-clade of the South-Pacific group. To our knowledge, this is the first report of BBTV infecting bananas in Tanzania, and East Africa endowed with rich banana diversity and popular East African Highland banana clone. BBTV presents a new threat to banana production in this sub-region due to the high risk of further spread through vegetative propagation, traditional planting material exchange practices, and the ubiquitous banana aphid vector. This study warrants delimitation surveys to assess the extent of spread, with simultaneous efforts to raise awareness about BBTD recognition and control measures among banana growers, including eradicating infected mats and replanting with healthy planting material to recover banana production.


2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Hafte Kahsay Kebede ◽  
Lillian Mwanri ◽  
Paul Ward ◽  
Hailay Abrha Gesesew

Abstract Background It is known that ‘drop out’ from human immunodeficiency virus (HIV) treatment, the so called lost-to-follow-up (LTFU) occurs to persons enrolled in HIV care services. However, in sub-Saharan Africa (SSA), the risk factors for the LTFU are not well understood. Methods We performed a systematic review and meta-analysis of risk factors for LTFU among adults living with HIV in SSA. A systematic search of literature using identified keywords and index terms was conducted across five databases: MEDLINE, PubMed, CINAHL, Scopus, and Web of Science. We included quantitative studies published in English from 2002 to 2019. The Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI) was used for methodological validity assessment and data extraction. Mantel Haenszel method using Revman-5 software was used for meta-analysis. We demonstrated the meta-analytic measure of association using pooled odds ratio (OR), 95% confidence interval (CI) and heterogeneity using I2 tests. Results Thirty studies met the search criteria and were included in the meta-analysis. Predictors of LTFU were: demographic factors including being: (i) a male (OR = 1.2, 95% CI 1.1–1.3, I2 = 59%), (ii) between 15 and 35 years old (OR = 1.3, 95% CI 1.1–1.3, I2 = 0%), (iii) unmarried (OR = 1.2, 95% CI 1.2–1.3, I2 = 21%), (iv) a rural dweller (OR = 2.01, 95% CI 1.5–2.7, I2 = 40%), (v) unemployed (OR = 1.2, 95% CI 1.04–1.4, I2 = 58%); (vi) diagnosed with behavioral factors including illegal drug use(OR = 13.5, 95% CI 7.2–25.5, I2 = 60%), alcohol drinking (OR = 2.9, 95% CI 1.9–4.4, I2 = 39%), and tobacco smoking (OR = 2.6, 95% CI 1.6–4.3, I2 = 74%); and clinical diagnosis of mental illness (OR = 3.4, 95% CI 2.2–5.2, I2 = 1%), bed ridden or ambulatory functional status (OR = 2.2, 95% CI 1.5–3.1, I2 = 74%), low CD4 count in the last visit (OR = 1.4, 95% CI 1.1–1.9, I2 = 75%), tuberculosis co-infection (OR = 1.2, 95% CI 1.02–1.4, I2 = 66%) and a history of opportunistic infections (OR = 2.5, 95% CI 1.7–2.8, I2 = 75%). Conclusions The current review identifies demographic, behavioral and clinical factors to be determinants of LTFU. We recommend strengthening of HIV care services in SSA targeting the aforementioned group of patients. Trial registration Protocol: the PROSPERO Registration Number is CRD42018114418


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Almahamoudou Mahamar ◽  
Kjerstin Lanke ◽  
Wouter Graumans ◽  
Halimatou Diawara ◽  
Koualy Sanogo ◽  
...  

Abstract Background Malaria control in sub-Saharan Africa relies upon prompt case management with artemisinin-based combination therapy (ACT). Ring-stage parasite mRNA, measured by sbp1 quantitative reverse-transcriptase PCR (qRT-PCR), was previously reported to persist after ACT treatment and hypothesized to reflect temporary arrest of the growth of ring-stage parasites (dormancy) following exposure to artemisinins. Here, the persistence of ring-stage parasitaemia following ACT and non-ACT treatment was examined. Methods Samples were used from naturally infected Malian gametocyte carriers who received dihydroartemisinin–piperaquine (DP) or sulfadoxine–pyrimethamine (SP–AQ) with or without gametocytocidal drugs. Gametocytes and ring-stage parasites were quantified by qRT-PCR during 42 days of follow-up. Results At baseline, 89% (64/73) of participants had measurable ring-stage parasite mRNA. Following treatment, the proportion of ring-stage parasite-positive individuals and estimated densities declined for all four treatment groups. Ring-stage parasite prevalence and density was generally lower in arms that received DP compared to SP–AQ. This finding was most apparent days 1, 2, and 42 of follow-up (p < 0.01). Gametocytocidal drugs did not influence ring-stage parasite persistence. Ring-stage parasite density estimates on days 14 and 28 after initiation of treatment were higher among individuals who subsequently experienced recurrent parasitaemia compared to those who remained free of parasites until day 42 after initiation of treatment (pday 14 = 0.011 and pday 28 = 0.068). No association of ring-stage persistence with gametocyte carriage was observed. Conclusions The current findings of lower ring-stage persistence after ACT without an effect of gametocytocidal partner drugs affirms the use of sbp1 as ring-stage marker. Lower persistence of ring-stage mRNA after ACT treatment suggests the marker may not reflect dormant parasites whilst it was predictive of re-appearance of parasitaemia.


2018 ◽  
Vol 28 (2) ◽  
pp. 197-200 ◽  
Author(s):  
L. Missounga ◽  
J. Iba Ba ◽  
I.R. Nseng Nseng Ondo ◽  
M.I.C. Nziengui Madjinou ◽  
D. Mwenpindi Malekou ◽  
...  

2021 ◽  
pp. 198487
Author(s):  
Joshua Sikhu Okonya ◽  
Heidy Gamarra ◽  
Anastase Nduwayezu ◽  
Astere Bararyenya ◽  
Jürgen Kroschel ◽  
...  

2010 ◽  
Vol 10 (3) ◽  
pp. 155-166 ◽  
Author(s):  
Roos E Barth ◽  
Maarten F Schim van der Loeff ◽  
Rob Schuurman ◽  
Andy IM Hoepelman ◽  
Annemarie MJ Wensing

Author(s):  
Biniyam A. Ayele ◽  
Hanna Demissie ◽  
Meron Awraris ◽  
Wondwossen Amogne ◽  
Ali Shalash ◽  
...  

2019 ◽  
Vol 6 (2) ◽  
pp. 1-9
Author(s):  
Ayun Kotokai Cassell ◽  
Mohamed Jalloh ◽  
Bashir Yunusa ◽  
Medina Ndoye ◽  
Mouhamadou Mbodji ◽  
...  

There is a global variation in the incidence of renal masses with the developed nations having a greater incidence. About 80–90% of renal malignancies are renal cell carcinomas (RCC) which account for 2–4% of all cancers. In Africa and the Middle East, the age-standardized incidence for RCC is 1.8–4.8/100,000 for males and 1.2–2.2/100,000 for females. The management of renal cell cancer is challenging. A multidisciplinary approach is effective for diagnosis, staging, and treatment. Guidelines recommend active surveillance, thermal ablation, partial nephrectomy, radical nephrectomy, cytoreductive nephrectomy and immunotherapy as various modalities for various stages of RCC. However, open radical nephrectomy is most widely adopted as an option for treatment at various stages of the disease in sub-Saharan Africa due to its cost-effectiveness, applicability at various stages, and the reduced cost of follow-up. Nevertheless, most patients in the region present with the disease in the advanced stage and despite surgery the prognosis is poor.


2020 ◽  
Author(s):  
Martin Njoroge ◽  
Sarah Rylance ◽  
Rebecca Nightingale ◽  
Stephen Gordon ◽  
Kevin Mortimer ◽  
...  

AbstractPurposeThe Chikwawa lung health cohort was established in rural Malawi in 2014 to prospectively determine the prevalence and causes of lung disease amongst the general population of adults living in a low-income rural setting in Sub-Saharan Africa.ParticipantsA total of 1481 participants were randomly identified and recruited in 2014 for the baseline study. We collected data on demographic, socio-economic status, respiratory symptoms and potentially relevant exposures such as smoking, household fuels, environmental exposures, occupational history/exposures, dietary intake, healthcare utilization, cost (medication, outpatient visits and inpatient admissions) and productivity losses. Spirometry was performed to assess lung function. At baseline, 56.9% of the participants were female, a mean age of 43.8 (SD:17.8) and mean body mass index (BMI) of 21.6 Kg/m2 (SD: 3.46)Findings to dateCurrently, two studies have been published. The first reported the prevalence of chronic respiratory symptoms (13.6%, 95% confidence interval [CI], 11.9 – 15.4), spirometric obstruction (8.7%, 95% CI, 7.0 – 10.7), and spirometric restriction (34.8%, 95% CI, 31.7 – 38.0). The second reported annual decline in forced expiratory volume in one second [FEV1] of 30.9mL/year (95% CI: 21.6 to 40.1) and forced vital capacity [FVC] by 38.3 mL/year (95% CI: 28.5 to 48.1).Future plansThe ongoing current phase of follow-up will determine the annual rate of decline in lung function as measured through spirometry, and relate this to morbidity, mortality and economic cost of airflow obstruction and restriction. Population-based mathematical models will be developed driven by the empirical data from the cohort and national population data for Malawi to assess the effects of interventions and programmes to address the lung burden in Malawi. The present follow-up study started in 2019.Strengths and limitations of this studyThis is an original cohort study comprising adults randomly identified in a low-income Sub-Saharan African Setting.The repeated follow up of the cohort has included objective measures of lung function.The cohort has had high rates of case ascertainment that include verbal autopsies.The study will include an analysis of the health economic consequences of rate of change of lung function and health economic modelling of impact of lung diseases and potential interventions that could be adopted.A main limitation of our study is the systematic bias may be introduced through the self-selection of the participants who agreed to take part in the study to date and the migration of individuals from Chikwawa.


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