scholarly journals “Slash and Clear”, a Community-Based Vector Control Method to Reduce Onchocerciasis Transmission by Simulium sirbanum in Maridi, South Sudan: A Prospective Study

Pathogens ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1329
Author(s):  
Stephen Raimon ◽  
Tom L. Lakwo ◽  
Wilson John Sebit ◽  
Joseph Nelson Siewe Fodjo ◽  
Peter Alinda ◽  
...  
Keyword(s):  
Vector Control ◽  
Control Method ◽  
South Sudan ◽  
Breeding Site ◽  
Black Flies ◽  
Community Based ◽  
Simulium Damnosum ◽  
Human Landing ◽  
A Prospective Study ◽  
Onchocerciasis Control

Background: High ongoing Onchocerca volvulus transmission was recently documented in Maridi County, South Sudan. To complement community-directed treatment with ivermectin (CDTI) as the main onchocerciasis control strategy, we initiated a community-based vector control method “slash and clear” at the Maridi dam, a Simulium damnosum s.l. breeding site, to reduce O. volvulus transmission. Methods: Simulium damnosum s.l. biting rates were collected before and during the twenty months following the “slash and clear” intervention using the human landing catches. Black flies were dissected to measure parity rates before and twelve months after the intervention. Larvae and pupae of S. damnosum s.l. were collected from the dam for morphological and chromosomal characterization to identify the cytospecies involved. Results: Biting rates of S. damnosum s.l. close to the Maridi dam spillway decreased by >90% post-“slash and clear” for more than six months. Twelve months after the “slash and clear” intervention, the reduction in biting rates was still at <50% (p = 0.0007). Parity rates reduced from 13% pre-“slash and clear” (November 2019) to 5.6% post-“slash and clear” (November 2020). Larvae collected from the dam were identified as Simulium sirbanum. Conclusion: The “slash and clear” method was found to be an effective and cheap community-based method to reduce black fly biting rates caused by S. sirbanum. When repeated at least annually together with a high CDTI coverage, this intervention has the potential to considerably accelerate onchocerciasis elimination.

The WHO Onchocerciasis Control Programme: Retrospect and prospects

1990 ◽  
Vol 328 (1251) ◽  
pp. 721-729 ◽  
Keyword(s):  
West Africa ◽  
Insecticide Resistance ◽  
Vector Control ◽  
Species Complex ◽  
Control Programme ◽  
Related Research ◽  
Simulium Damnosum ◽  
The Future ◽  
History Of ◽  
Onchocerciasis Control

The history of onchocerciasis control in Africa and the genesis of the WHO Onchocerciasis Control Programme in West Africa (OCP) are briefly reviewed. The importance of experience gained in anti-locust campaigns in helping to plan the OCP is stressed. Members of the Simulium damnosum species complex are the vectors of onchocerciasis, which OCP is controlling with insecticide treatments on the stretches of rivers where the Simulium breed. Migrations of flies have been responsible for reinfestations of controlled areas and the spread of insecticide resistance. The management of these problems and related research are described, but it is emphasized that despite setbacks OCP is achieving its aims. A strategy for the future is outlined: vector control supplemented by chemotherapy is expected to continue until the year 2004.

scholarly journals Onchocerciasis control in Ghana (1974–2016)

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nana-Kwadwo Biritwum ◽  
Dziedzom K. de Souza ◽  
Odame Asiedu ◽  
Benjamin Marfo ◽  
Uche Veronica Amazigo ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Vector Control ◽  
Control Strategy ◽  
Financial Support ◽  
Control Programme ◽  
Ivermectin Treatment ◽  
Mobile Community ◽  
The Mean ◽  
The Impact ◽  
Onchocerciasis Control

Abstract Background The control of onchocerciasis in Ghana started in 1974 under the auspices of the Onchocerciasis Control Programme (OCP). Between 1974 and 2002, a combination of approaches including vector control, mobile community ivermectin treatment, and community-directed treatment with ivermectin (CDTI) were employed. From 1997, CDTI became the main control strategy employed by the Ghana OCP (GOCP). This review was undertaken to assess the impact of the control interventions on onchocerciasis in Ghana between 1974 and 2016, since which time the focus has changed from control to elimination. Methods In this paper, we review programme data from 1974 to 2016 to assess the impact of control activities on prevalence indicators of onchocerciasis. This review includes an evaluation of CDTI implementation, microfilaria (Mf) prevalence assessments and rapid epidemiological mapping of onchocerciasis results. Results This review indicates that the control of onchocerciasis in Ghana has been very successful, with a significant decrease in the prevalence of infection from 69.13% [95% confidence interval) CI 60.24–78.01] in 1975 to 0.72% (95% CI 0.19–1.26) in 2015. Similarly, the mean community Mf load decreased from 14.48 MF/skin snip in 1975 to 0.07 MF/skin snip (95% CI 0.00–0.19) in 2015. Between 1997 and 2016, the therapeutic coverage increased from 58.50 to 83.80%, with nearly 100 million ivermectin tablets distributed. Conclusions Despite the significant reduction in the prevalence of onchocerciasis in Ghana, there are still communities with MF prevalence above 1%. As the focus of the GOCP has changed from the control of onchocerciasis to its elimination, both guidance and financial support are required to ensure that the latter goal is met.

Variable Speed Vector Control for Induction Motor of Electric Vehicle

2014 ◽  
Vol 699 ◽  
pp. 759-764
Author(s):  
Amilia Emil Hasan ◽  
Haryani Hassan ◽  
Ismadi Bugis
Keyword(s):  
Embedded System ◽  
Vector Control ◽  
Induction Motor ◽  
Control Method ◽  
Torque Ripple ◽  
Electromagnetic Torque ◽  
Motor Speed ◽  
Speed Controller ◽  
Speed Performance ◽  
Constant Output

This paper presents the speed performance of an induction motor by using a vector control. The control scheme used is an indirect vector control for define speed command. The main focus of this research is to observe on the dynamic speed performance of the induction motor when the command speed is given to the motor. In this study, the system of indirect vector control will be built by using Matlab Simulink. In fact, the expression of exciting flux linkage and electromagnetic torque are used to create a simple embedded system which to find out the effects of flux weakening in motor while, the gain of the speed controller is 100. The result shows that the vector control method will cause immediate the motor speed response with a small electromagnetic torque ripple. Furthermore, the output mechanical torque starts to decrease when the motor speed above the base speed to maintain a constant output power operation. This paper contributes a new algorithm to analysis the system when the speed motor is higher than a base speed.

scholarly journals New Records of Anopheles benarrochi B (Diptera: Culicidae) in Malaria Hotspots in the Amazon Regions of Ecuador and Peru

2021 ◽  
Author(s):  
Diego Morales Viteri ◽  
Manuela Herrera-Varela ◽  
Maribel Albuja ◽  
Cristina Quiroga ◽  
Gloria Diaz ◽  
...  
Keyword(s):  
Vector Control ◽  
Malaria Transmission ◽  
New Records ◽  
Final Analysis ◽  
Human Landing Catch ◽  
Light Traps ◽  
Control Units ◽  
Pcr Rflp ◽  
Human Landing ◽  
First Time

Abstract The increase in malaria transmission in the Amazon region motivated vector control units of the Ministry of Health of Ecuador and Peru to investigate Anopheles (Diptera: Culicidae) species present in transmission hotspots. Mosquitoes were collected using prokopack aspirators and CDC light traps (Ecuador) and human landing catch in Peru. In Ecuador, 84 Anopheles were captured from Pastaza, Morona Santiago, and Orellana provinces and identified morphologically [An. (An.) apicimacula Dyar and Knab, An. (Nys.) near benarrochi, An. (Nys.) near oswaldoi, An. (Nys.) near strodei, An. (An.) nimbus (Theobald, 1902), and An. (Nyssorhynchus) sp.]. In Peru, 1,150 Anopheles were collected in Andoas District. A subsample of 166 specimens was stored under silica and identified as An. near oswaldoi, An. darlingi, and An. (An.) mattogrossensis Lutz and Neiva. COI barcode region sequences were obtained for 137 adults (107 from Peru, 30 from Ecuador) identified by ITS2 PCR-RFLP as An. benarrochi Gabaldon, Cova Garcia, and Lopez and retained in the final analysis. Haplotypes from the present study plus An. benarrochi B GenBank sequences grouped separately from Brazilian An. benarrochi GenBank sequences by 44 mutation steps, indicating that the present study specimens were An. benarrochi B. Our findings confirm the presence of An. benarrochi B in Ecuador and reported here for the first time from the Amazonian provinces of Orellana and Morona Santiago. Furthermore, we confirm that the species collected in Andoas District in the Datem del Maranon Province, Peru, is An. benarrochi B, and we observed that it is highly anthropophilic. Overall, the known distribution of An. benarrochi B has been extended and includes southern Colombia, much of Peru and eastern Ecuador.

scholarly journals First, do no harm: the risks of overtreating children with epilepsy

2007 ◽  
Vol 65 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Eunice Chuang ◽  
Marilisa M. Guerreiro ◽  
Sara Y. Tsuchie ◽  
Angelica Santucci ◽  
Carlos A. M. Guerreiro ◽  
...  
Keyword(s):  
Adverse Events ◽  
Prospective Study ◽  
Antiepileptic Drug ◽  
Antiepileptic Drugs ◽  
Seizure Frequency ◽  
Seizure Control ◽  
Control Method ◽  
Refractory Epilepsy ◽  
Do No Harm ◽  
A Prospective Study

BACKGROUND: Although overtreatment with antiepileptic drugs contributes to the morbidity associated with epilepsy, many children still are overtreated. OBJECTIVE: To evaluate if the withdrawal of at least one antiepileptic drug (AED) in children with refractory epilepsy using polytherapy enable a better seizure control. METHOD: This was a prospective study. Children with refractory epilepsy using at least two AEDs were included. Once the patient, or guardian, agreed to participate in the study, one or more AED were slowly tapered off. The remaining AEDs dosages could be adjusted as needed, but a new AED could not be introduced. RESULTS: Fifteen patients were evaluated, three girls; ages ranging from 3 to 18 (mean=8.7 years). After at least one AED withdrawal, two (13.5%) patients became seizure free, seizures improved >50% in 5 (33.5%) patients, did not change in 5 (33.5%), and seizure frequency became worse in 3 (20%). Adverse events improved in 12 patients (80%). CONCLUSION: The withdrawal of at least one AED is a valuable option in the treatment of selected children with refractory epilepsy.

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