scholarly journals A Microsporidian blocksPlasmodium falciparumtransmission inAnopheles arabiensismosquitoes

2019 ◽  
Author(s):  
Jeremy K. Herren ◽  
Lilian Mbaisi ◽  
Enock Mararo ◽  
Joseph W. Oundo ◽  
Edward E. Makhulu ◽  
...  
Keyword(s):  
Experimental Infection ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Transmission Blocking ◽  
Block Transmission ◽  
Control Approach ◽  
Geographically Dispersed ◽  
Sub Saharan ◽  
Blocking Capacity ◽  
Control Tool

Malaria imposes an enormous burden on sub-Saharan Africa, and evidence that incidence could be starting to increase again1suggests the limits of currently applied control strategies have now been reached. A possible novel control approach involves the dissemination in mosquitoes of inherited symbiotic microbes to block transmission. This strategy is exemplified by the use of transmission-blockingWolbachiainAedes aegyptiagainst dengue virus2–7. However, in theAnopheles gambiaecomplex, the primary African vectors of malaria, there limited reports of inherited symbionts with transmission-blocking capacity8–10. Here we show that a newly discovered vertically transmitted species ofMicrosporidiasymbiont in theAn. gambiaecomplex blocksPlasmodiumtransmission.Microsporidia MBis present at moderate prevalence in geographically dispersed populations ofAn. arabienesisin Kenya, localized to the mosquito midgut and ovaries, and is not associated with significant reductions in adult host fecundity or survival. Field collectedMicrosporidia MB-infectedAn. arabiensiswere never found to harborP. falciparumgametocytes and on experimental infection withP. falciparumno sporozoites could be detected inMicrosporidia MB-infected mosquitos. As aPlasmodiumtransmission-blocking microbe that is non-virulent and vertically transmitted,Microsporidia MBcould be exploited as a novel malaria control tool.

scholarly journals Prevalence of mastitis in Nigerian livestock: a Review

2020 ◽  
Vol 1 (1) ◽  
pp. 20-29
Author(s):  
Hussaini Ojagefu Adamu ◽  
Rahimat Oshuwa Hussaini ◽  
Cedric Obasuyi ◽  
Linus Irefo Anagha ◽  
Gabriel Oscy Okoduwa
Keyword(s):  
Control Strategies ◽  
Dairy Farms ◽  
Livestock Production ◽  
Sub Saharan Africa ◽  
Economic Losses ◽  
Ecological Development ◽  
Management Plans ◽  
Sub Saharan ◽  
Control And Management ◽  
The Impact

AbstractMastitis is a disease of livestock that directly impede livestock production and thus hindering the socio-ecological development of sub-Saharan Africa. Studies have estimated the prevalence of this disease in 30% of Africa countries, with Ethiopia having the highest prevalence. The coverage is low, despite the wide livestock and dairy farms distribution in Africa. Furthermore, estimated economic losses due to the impact of mastitis are lacking in Nigeria. The disease is endemic in Nigeria as indicated by the available data and there are no proposed management plans or control strategies. This review is thus presented to serve as a wakeup call to all parties involved to intensify efforts towards the diagnosis, control, and management of the disease in Nigeria.

scholarly journals Research on Invasive Nontyphoidal Salmonella Disease and Developments Towards Better Understanding of Epidemiology, Management, and Control Strategies

2020 ◽  
Vol 71 (Supplement_2) ◽  
pp. S127-S129
Author(s):  
Samuel Kariuki ◽  
Ellis Owusu-Dabo
Keyword(s):  
Burden Of Illness ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Disease Entity ◽  
Middle Income ◽  
Diagnostic Strategies ◽  
Disease Epidemiology ◽  
Middle Income Countries ◽  
Sub Saharan ◽  
And Control

Abstract During the 11th International Conference on Typhoid and Other Invasive Salmonelloses held in Hanoi, Vietnam, a number of papers were presented on the burden of disease, epidemiology, genomics, management, and control strategies for invasive nontyphoidal Salmonella (iNTS) disease, which is increasingly becoming an important public health threat in low- and middle-income countries, but especially in sub-Saharan Africa (sSA). Although there were minor variations in characteristics of iNTS in different settings (urban vs rural, country to country), it was observed that iNTS has gained greater recognition as a major disease entity in children younger than 5 years. Renewed efforts towards greater understanding of the burden of illness, detection and diagnostic strategies, and management and control of the disease in communities in sSA through the introduction of vaccines will be important.

scholarly journals Identification of Three Novel Plasmodium Factors Involved in Ookinete to Oocyst Developmental Transition

2021 ◽  
Vol 11 ◽  
Author(s):  
Chiamaka V. Ukegbu ◽  
George K. Christophides ◽  
Dina Vlachou
Keyword(s):  
Plasmodium Falciparum ◽  
Plasmodium Berghei ◽  
Disease Transmission ◽  
Sub Saharan Africa ◽  
Parasite Transmission ◽  
Targeted Disruption ◽  
Transmission Blocking ◽  
Essential Function ◽  
Sub Saharan ◽  
Transmission Biology

Plasmodium falciparum malaria remains a major cause of global morbidity and mortality, mainly in sub-Saharan Africa. The numbers of new malaria cases and deaths have been stable in the last years despite intense efforts for disease elimination, highlighting the need for new approaches to stop disease transmission. Further understanding of the parasite transmission biology could provide a framework for the development of such approaches. We phenotypically and functionally characterized three novel genes, PIMMS01, PIMMS57, and PIMMS22, using targeted disruption of their orthologs in the rodent parasite Plasmodium berghei. PIMMS01 and PIMMS57 are specifically and highly expressed in ookinetes, while PIMMS22 transcription starts already in gametocytes and peaks in sporozoites. All three genes show strong phenotypes associated with the ookinete to oocyst transition, as their disruption leads to very low numbers of oocysts and complete abolishment of transmission. PIMMS22 has a secondary essential function in the oocyst. Our results enrich the molecular understanding of the parasite-vector interactions and identify PIMMS01, PIMMS57, and PIMMS22 as new targets of transmission blocking interventions.

scholarly journals Genetic Diversity of Mitochondrial DNA of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Associated with Cassava and the Occurrence of Cassava Mosaic Disease in Zambia

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 761
Author(s):  
Patrick Chiza Chikoti ◽  
Mathias Tembo ◽  
James Peter Legg ◽  
Rudolph Rufini Shirima ◽  
Habibu Mugerwa ◽  
...  
Keyword(s):  
Bemisia Tabaci ◽  
Control Strategies ◽  
Mosaic Disease ◽  
Sub Saharan Africa ◽  
Cassava Mosaic Disease ◽  
Northern Province ◽  
Western Province ◽  
Key Factor ◽  
Sub Saharan ◽  
Brown Streak

Bemisia tabaci is an important vector of cassava brown streak viruses and cassava mosaic begomoviruses, the causal agents of cassava brown streak disease and cassava mosaic disease (CMD), respectively. A study was carried out to determine the genetic variability of B. tabaci associated with cassava and the occurrence of CMD in Zambia in 2013 and 2015. Phylogenetic analysis showed the presence of only the sub-Saharan Africa 1 (SSA1) genetic group in Zambia. The SSA1 population had three population subgroups (SGs): SSA1-SG1, SSA1-SG2 and SSA1-SG3. All three SSA1 population subgroups occurred in Western Province. However, only SSA1-SG3 occurred in Eastern Province, while only SSA1-SG1 occurred in North Western and Luapula Provinces. Adult B. tabaci were most abundant in Western Province in 2013 (11.1/plant) and 2015 (10.8/plant), and least abundant (0.2/plant) in Northern Province in both 2013 and 2015. CMD was prevalent in all seven provinces surveyed, with the highest incidence recorded in Lusaka Province in both 2013 (78%) and 2015 (83.6%), and the lowest in Northern Province in both 2013 (26.6%) and 2015 (29.3%). Although SSA1-SG1 occurred at greater abundances than the other subgroups, there was no direct association demonstrated between whitefly subgroup and incidence of CMD. Establishing which B. tabaci genetic groups and populations are associated with CMD and their distribution in the country is a key factor in guiding the development of CMD control strategies for cassava-dependent households.

Antibiotics resistance in Sub Saharan Africa; literature review from 2010 – 2017

2020 ◽  
Vol 37 ◽  
pp. 35-45
Author(s):  
A. Balala ◽  
T.G. Huong ◽  
S.G. Fenwick
Keyword(s):  
Bacterial Infections ◽  
Control Strategies ◽  
Antibiotic Use ◽  
Sub Saharan Africa ◽  
Resistant Bacteria ◽  
Antibiotics Resistance ◽  
Published Data ◽  
African Countries ◽  
Antibiotic Resistant ◽  
Sub Saharan

Antibiotics saves millions of lives in human and animal from bacterial infections, but resistance has been occurred and spreading borderless which pose health and economic problems. This study aimed to describe epidemiology (prevalence) of antibiotic resistant bacteria in human and animals and describing risk factors with strategic control efforts in Sub-Sahara Africa countries. Total 72 articles published from 2010 to 2017 were reviewed which reported on bacterium resistance to commonly-used antibiotics of different groups. Majority of isolated bacteria were highly resistant to b-lactams, Tetracycline and Sulphonamide, moderate resistant to Gentamycine and Aminoglycoside with low resistant to cephalosporin and quinolones for bacteria isolated from human while isolates from animal have high resistance to majority of antibiotic. High antibiotic resistant was associated by presence of weak/no regulation and irrational antibiotics use in Animal and Human health system, despite there is paucity of published data from central and southern African countries, lack of data sharing among laboratories and presence of few initiatives on control strategies of antimicrobial resistance while most of them are faced by resource limitations (skilled personnel, Equipments and Fund allocation). This study recommend that awareness on rational antibiotic use must be created, strong regulation to limit accessibility of antibiotics over the counter prescription, strengthening laboratory based diagnosis and surveillance, Infection control and prevention in hospitals with strong biosafety and biosecurity in animal farms are crucial. Adoption of “One Health Approach” is very important through multisectoral involvement, information sharing and networking.

War and Disease: Recent Trends and Future Threats

War Epidemics ◽  
2004 ◽  
Author(s):  
Matthew Smallman-Raynor ◽  
Andrew Cliff
Keyword(s):  
Infectious Disease ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Biological Weapons ◽  
Modern World ◽  
Economic Competition ◽  
Global Pattern ◽  
Current Century ◽  
Sub Saharan ◽  
International Peacekeeping

In the foregoing chapters, we have focused on the intersection of war and infectious disease over the 140-year period from 1850. We have examined long-term trends in disease activity in civil, military, and displaced populations (Chs. 3–5), outlined some of the analytical approaches used to describe the spread of war epidemics (Ch. 6), and we have explored in a regional context recurring themes at the interface of war and infectious disease (Chs. 7–12). In this concluding chapter, we examine the epidemiological consequences of wars and war-like events in the years since 1990.We begin in Section 13.2 by reviewing the empirical evidence for the spread of diseases in association with three recent conflicts: the Gulf War (1990–1); the Bosnian Civil War (1992–5); and Afghanistan and the ‘War on Terrorism’ (2001–). In Section 13.3, we examine the role of war both as an obstacle to disease eradication and to disease-control strategies while, in Section 13.4, we focus on biological weapons as one of the foremost threats to global security in the modern world. Finally, in Section 13.5, we isolate a series of further war-related issues (militarism; economic sanctions; international peacekeeping; disease re-emergence; and post-combat syndromes) that—given the balance of probabilities—are likely to be of continuing epidemiological significance in the current century. As we enter a new millennium, there is an undercurrent of academic thought that nuclear weaponary and the end of the Cold War have rendered war obsolete; that war is, and will be, increasingly supplanted by economic competition between states and regions (see e.g. Black, 2000).Yet it is clear from Figure 13.1 that wars—of greater or lesser intensity—have continued to increase, rather than decrease, in number over the last few decades. This increase has remained largely focused in the less developed regions of the world (van der Wusten, 1985; Brogan, 1992; Arnold, 1995). By way of illustration, Figure 13.2 delimits the global pattern of conflict in the year 2000. As the map shows, levels of conflict intensity were highest in some of the poorest of the world’s regions—in Sub-Saharan Africa, Central and South Asia (Murray et al., 2002).

scholarly journals Using mobile phone data to reveal risk flow networks underlying the HIV epidemic in Namibia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Eugenio Valdano ◽  
Justin T. Okano ◽  
Vittoria Colizza ◽  
Honore K. Mitonga ◽  
Sally Blower
Keyword(s):  
Large Scale ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Mobile Phone Data ◽  
Mathematical Framework ◽  
Sub Saharan ◽  
Administrative Units ◽  
Large Scale Networks ◽  
Living With Hiv ◽  
Very High

AbstractTwenty-six million people are living with HIV in sub-Saharan Africa; epidemics are widely dispersed, due to high levels of mobility. However, global elimination strategies do not consider mobility. We use Call Detail Records from 9 billion calls/texts to model mobility in Namibia; we quantify the epidemic-level impact by using a mathematical framework based on spatial networks. We find complex networks of risk flows dispersed risk countrywide: increasing the risk of acquiring HIV in some areas, decreasing it in others. Overall, 40% of risk was mobility-driven. Networks contained multiple risk hubs. All constituencies (administrative units) imported and exported risk, to varying degrees. A few exported very high levels of risk: their residents infected many residents of other constituencies. Notably, prevalence in the constituency exporting the most risk was below average. Large-scale networks of mobility-driven risk flows underlie generalized HIV epidemics in sub-Saharan Africa. In order to eliminate HIV, it is likely to become increasingly important to implement innovative control strategies that focus on disrupting risk flows.

scholarly journals Co-Circulation of Multiple Serotypes of Bluetongue Virus in Zambia

Viruses ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 963
Author(s):  
Herman M. Chambaro ◽  
Michihito Sasaki ◽  
Edgar Simulundu ◽  
Isaac Silwamba ◽  
Yona Sinkala ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Bluetongue Virus ◽  
Prevention And Control ◽  
Control Strategies ◽  
Viral Disease ◽  
Sub Saharan Africa ◽  
High Seroprevalence ◽  
Economic Implications ◽  
Sub Saharan ◽  
And Control

Bluetongue (BT) is an arthropod-borne viral disease of ruminants with serious trade and socio-economic implications. Although the disease has been reported in a number of countries in sub-Saharan Africa, there is currently no information on circulating serotypes and disease distribution in Zambia. Following surveillance for BT in domestic and wild ruminants in Zambia, BT virus (BTV) nucleic acid and antibodies were detected in eight of the 10 provinces of the country. About 40% (87/215) of pooled blood samples from cattle and goats were positive for BTV nucleic acid, while one hartebeest pool (1/43) was positive among wildlife samples. Sequence analysis of segment 2 revealed presence of serotypes 3, 5, 7, 12 and 15, with five nucleotypes (B, E, F, G and J) being identified. Segment 10 phylogeny showed Zambian BTV sequences clustering with Western topotype strains from South Africa, intimating likely transboundary spread of BTV in Southern Africa. Interestingly, two Zambian viruses and one isolate from Israel formed a novel clade, which we designated as Western topotype 4. The high seroprevalence (96.2%) in cattle from Lusaka and Central provinces and co-circulation of multiple serotypes showed that BT is widespread, underscoring the need for prevention and control strategies.

scholarly journals Novel Wolbachia strains in Anopheles malaria vectors from Sub-Saharan Africa

2018 ◽  
Vol 3 ◽  
pp. 113 ◽  
Author(s):  
Claire L. Jeffries ◽  
Gena G. Lawrence ◽  
George Golovko ◽  
Mojca Kristan ◽  
James Orsborne ◽  
...  
Keyword(s):  
Control Strategies ◽  
Mosquito Species ◽  
Amplicon Sequencing ◽  
Pathogen Transmission ◽  
Sub Saharan Africa ◽  
Malaria Vectors ◽  
Endosymbiotic Bacterium ◽  
Prevalence Rates ◽  
Republic Of The Congo ◽  
Sub Saharan

Background: Wolbachia, a common insect endosymbiotic bacterium that can influence pathogen transmission and manipulate host reproduction, has historically been considered absent from the Anopheles (An.) genera, but has recently been found in An. gambiae s.l. populations.  As there are numerous Anopheles species that have the capacity to transmit malaria, we analysed a range of species to determine Wolbachia prevalence rates, characterise novel Wolbachia strains and determine any correlation between the presence of Plasmodium, Wolbachia and the competing endosymbiotic bacterium Asaia. Methods: Anopheles adult mosquitoes were collected from five malaria-endemic countries: Guinea, Democratic Republic of the Congo (DRC), Ghana, Uganda and Madagascar, between 2013 and 2017.  Molecular analysis of samples was undertaken using quantitative PCR, Sanger sequencing, Wolbachia multilocus sequence typing (MLST) and high-throughput amplicon sequencing of the bacterial 16S rRNA gene.  Results: Novel Wolbachia strains were discovered in five species: An. coluzzii, An. gambiae s.s., An. arabiensis, An. moucheti and An. species ‘A’, increasing the number of Anopheles species known to be naturally infected. Variable prevalence rates in different locations were observed and novel strains were phylogenetically diverse, clustering with Wolbachia supergroup B strains.  We also provide evidence for resident strain variants within An. species ‘A’.  Wolbachia is the dominant member of the microbiome in An. moucheti and An. species ‘A’, but present at lower densities in An. coluzzii.  Interestingly, no evidence of Wolbachia/Asaia co-infections was seen and Asaia infection densities were also shown to be variable and location dependent.  Conclusions: The important discovery of novel Wolbachia strains in Anopheles provides greater insight into the prevalence of resident Wolbachia strains in diverse malaria vectors.  Novel Wolbachia strains (particularly high-density strains) are ideal candidate strains for transinfection to create stable infections in other Anopheles mosquito species, which could be used for population replacement or suppression control strategies.

scholarly journals Nontyphoidal Salmonella among Children under 5 Years Old in Sub-Saharan Africa and South Asia in the Global Enteric Multicenter Study

2021 ◽  
Author(s):  
Rina Das ◽  
Md. Ahshanul Haque ◽  
Mohammod Jobayer Chisti ◽  
Tahmeed Ahmed ◽  
Abu Syed Golam Faruque
Keyword(s):  
South Asia ◽  
Multicenter Study ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Severe Diarrhea ◽  
Asymptomatic Children ◽  
Toilet Facility ◽  
Sub Saharan ◽  
And Control ◽  
Children Under 5

Factors associated with nontyphoidal Salmonella (NTS) infection have not been well characterized to date. We aimed to compare the associated factors among children under age 5 years with NTS infection in sub-Saharan Africa and South Asia. Data from children having moderate-to-severe diarrhea (MSD) and asymptomatic children with NTS isolated from fecal specimens were extracted from the Global Enteric Multicenter Study (GEMS), conducted from December 2007 to March 2011. Compared with NTS-negative children, NTS-associated MSD cases in South Asia were associated with the presence of goat in the house (adjusted odds ratio [aOR]: 2.15; 95% confidence interval [CI]: 1.25–3.70) and handwashing after handling an animal (aOR: 2.26; 95% CI: 1.36–3.74). In sub-Saharan Africa, children with NTS associated MSD had a greater association with stunting (1.21 95% CI: 1.01–1.45), longer duration of diarrhea (aOR: 1.25 95% CI: 1.19–1.31); presence of cow in house (aOR: 1.54 95% CI: 1.09–2.16), handwashing after handling animal (aOR: 2.41 95% CI: 1.74–3.33). Drinking tube well water (aOR: 0.54 95% CI: 0.32–0.91), availability of toilet facility (aOR: 0.58 95% CI: 0.53–0.65), and handwashing before eating (aOR: 0.76 95% CI: 0.57–1.00) and after defecation (aOR: 0.80 95% CI: 0.69, 0.94) were found to be protective. The differentials between children of both regions having fecal NTS are distinct and underscore the need for policymaking for preventive and control strategies targeting stunted children.

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