The absence of endemic malaria transmission in Taiwan from 2002 to 2010: The implications of sustained malaria elimination in Taiwan

2012 ◽  
Vol 10 (5-6) ◽  
pp. 240-246 ◽  
Author(s):  
Ching-Min Wang ◽  
Susan C. Hu ◽  
Wen-Shin Hung ◽  
Hsiao-Ling Chang ◽  
Ho-Sheng Wu ◽  
...  
2016 ◽  
Vol 114 (2) ◽  
pp. E255-E264 ◽  
Author(s):  
Philip A. Eckhoff ◽  
Edward A. Wenger ◽  
H. Charles J. Godfray ◽  
Austin Burt

The renewed effort to eliminate malaria and permanently remove its tremendous burden highlights questions of what combination of tools would be sufficient in various settings and what new tools need to be developed. Gene drive mosquitoes constitute a promising set of tools, with multiple different possible approaches including population replacement with introduced genes limiting malaria transmission, driving-Y chromosomes to collapse a mosquito population, and gene drive disrupting a fertility gene and thereby achieving population suppression or collapse. Each of these approaches has had recent success and advances under laboratory conditions, raising the urgency for understanding how each could be deployed in the real world and the potential impacts of each. New analyses are needed as existing models of gene drive primarily focus on nonseasonal or nonspatial dynamics. We use a mechanistic, spatially explicit, stochastic, individual-based mathematical model to simulate each gene drive approach in a variety of sub-Saharan African settings. Each approach exhibits a broad region of gene construct parameter space with successful elimination of malaria transmission due to the targeted vector species. The introduction of realistic seasonality in vector population dynamics facilitates gene drive success compared with nonseasonal analyses. Spatial simulations illustrate constraints on release timing, frequency, and spatial density in the most challenging settings for construct success. Within its parameter space for success, each gene drive approach provides a tool for malaria elimination unlike anything presently available. Provided potential barriers to success are surmounted, each achieves high efficacy at reducing transmission potential and lower delivery requirements in logistically challenged settings.


2020 ◽  
Vol 47 (4) ◽  
Author(s):  
Riyani Setiyaningsih

Abstract The target of malaria elimination in Indonesia is expected to be achieved in 2030. One of the activities to support malaria elimination is vector surveillance. Several districts in Indonesia have certificates of malaria, including Jembrana, Bali Province, Bulukumba, South Sulawesi Province, and Bengkalis, Riau Province. Analysis of the presence of malaria vectors and Plasmodium needs to be done for the potential occurances of malaria transmission in eliminated malaria areas. Bioecology study of malaria vectors were conducted to determine receptivity status and others risk factors and the potential for malaria transmission based on ecosystems in Jembrana, Bulukumba and Bengkalis districts. As part of national research of disease vector and reservoir (Rikhus Vektora), mosquitoes and larval field-collection methods, molecular plasmodium detection and blood meal analyses were carried out according Rikhus vektora guidelines. The result showed that Anopheles kochi and An. tesselatus were positive confirmed with Plasmodium falciparum by using PCR in Jembrana, Bali province, which were found in non-forest ecosystems near settlements and beaches near settlements. In addition, Anopheles barbirostris, Anopheles vagus, and Anopheles peditaeniatus were also positive confirmed with P. falciparum by using similar methods in Bulukumba, South Sulawesi province. An. barbirostris was found in forest ecosystems near settlement, Anopheles vagus was found in remote forest ecosystems of settlements and beaches near settlements, and Anopheles peditaenistus was found in non-forest ecosystems near settlements. While Anopheles sinensis was confirmed positive with P. falciparum in Bengkalis, Riau province. Jembrana, Bulukumba and Bengkalis districts are recognized as receptive areas and have potential for re-transmission of malaria. Vector surveillance and the implementation of approriate vector control and migration surveillance are needed to ascertain wheter the positive Anopheles with positives Plasmodium falciparum getting the parasites from imported cases or there has been a local transmission (indigenous) in these areas. This information is needed to prevent malaria re-transmission in the eliminated areas. Keywords : elimination, malaria, vector Abstrak Target eliminasi malaria di Indonesia harapannya dapat dicapai tahun 2030. Salah satu kegiatan yang dilakukan untuk menunjang elimnasi malaria adalah surveilans vektor. Beberapa Kabupaten di Indonesia telah memperoleh serfikat eliminasi malaria diantaranya Kabupaten Jembrana Propinsi Bali, Bulukumba Propinsi Sulawesi Selatan, dan Bengkalis Propinsi Riau. Analisis keberadaan vektor dan patogen malaria perlu dilakukan untuk melihat potensi terjadinya penularan malaria kembali di daerah yang telah mendapatkan sertifikat eliminasi malaria. Studi bioekologi vektor malaria dilakukan untuk mengetahui status reseptivitas dan faktor risiko lainnya, serta potensi penularan malaria berbasis ekosistem di daerah tersebut. Sebagai bagian dari dari Riset khusus (rikhus) vektora, koleksi lapangan nyamuk dan jentik, prosedur deteksi melekuler plasmodium dan analisis pakan darah dilakukan dengan menggunakan pedoman Rikhus vektora. Hasil studi menunjukkan bahwa Anopheles kochi dan Anopheles tesselatus, yang masing-masing ditemukan di eksoistem non hutan dekat pemukiman dan pantai dekat pemukiman ditemukan positif mengandung Plasmodium falciparum di Kabupaten Jembrana, Bali. Sedangkan di Kabupaten Bulukumba, Sulawesi Selatan, Anopheles barbirostris, Anopheles vagus, dan Anopheles peditaeniatus merupakan spesies Anopheles yang terkonfirmasi positif mengandung P. falciparum. An. barbirostris ditemukan di ekosistem hutan dekat pemukiman, Anopheles vagus ditemukan di ekosistem hutan jauh pemukiman dan pantai dekat pemukiman, dan Anopheles peditaenistus ditemukan di ekosistem non hutan dekat pemukiman. Sedangkan Anopheles sinensis merupakan satu-satunya spesies Anopheles yang ditemukan positif mengandung P. falciparum di Kabupaten Bengkalis, Riau. Dari hasil studi menunjukkan, Kabupaten Jembrana, Bulukumba, dan Bengkalis merupakan daerah reseptif dan berpotensi terjadinya penularan kembali malaria. Surveilans vektor dan implementasi pengendalian vektor yang tepat serta surveilans migrasi secara ketat diperlukan untuk memastikan apakah Anopheles yang positif tersebut mendapatkan parasit P. falciparum dari kasus import ataukah memang sudah terjadi transmisi secara lokal (indigenous) di wilayah tersebut. Hal ini perlu dilakukan agar tidak terjadi penularan kembali malaria di daerah yang sudah tereliminasi tersebut. Kata kunci: eliminasi, malaria, vektor


2017 ◽  
Vol 17 (3) ◽  
Author(s):  
Gabriel Zorello Laporta

Abstract Malaria elimination is now set to occur in Brazil until 2030. While this achievement is feasible, as it is for other endemic regions worldwide, it is important to recognize resistance of parasites and vectors against anti-malarial interventions. Resistance against drugs and insecticides can lead to discontinuities of malaria transmission, known as residual malaria transmission. Herein, we described a novel phenomenon that is occurring in a residual malaria transmission scenario in the southeastern Atlantic forest. This novel phenomenon does not belong to what is known and therefore we decided to explain it based on an evolutionary perspective. Although it shall not be viewed as a threat to public health, the phenomenon has important aspects that should be highlighted. Specifically, it represents an adaptation of P. falciparum among vectors and hosts in the southeastern Atlantic forest. Knowledge about this phenomenon could be of importance, including to the on-going malaria elimination programs.


2020 ◽  
Author(s):  
jaishree raman ◽  
Laura Gast ◽  
Ryleen Balawanth ◽  
Sofonias Tessema ◽  
Basil Brooke ◽  
...  

Abstract Background: KwaZulu-Natal, one of South Africa’s three malaria endemic provinces, is nearing malaria elimination, reporting fewer than 100 locally-acquired cases annually since 2010. Despite sustained implementation of essential interventions, including annual indoor residual spraying, prompt case detection using malaria rapid diagnostics tests and treatment with effective artemisinin-based combination therapy, low-level focal transmission persists in the province. This malaria prevalence and entomological survey was therefore undertaken to identify the drivers of this residual transmission. Methods: Malaria prevalence as well as malaria knowledge, attitudes and practices among community members and mobile migrant populations within uMkhanyakude district, KwaZulu-Natal were assessed during a community-based malaria prevalence survey. All consenting participants were tested for malaria by both conventional and highly-sensitive falciparum-specific rapid diagnostic tests. Finger-prick filter-paper blood spots were also collected from all participants for downstream parasite genotyping analysis. Entomological investigations were conducted around the surveyed households, with potential breeding sites geolocated and larvae collected for species identification and insecticide susceptibility testing. A random selection of households were assessed for indoor residual spray quality by cone bioassay. Results: A low malaria prevalence was confirmed in the study area, with only 2% (67/2979) of the participants found to be malaria positive by both conventional and highly-sensitive falciparum-specific rapid diagnostic tests. Malaria prevalence however differed markedly between the border market and community (p < 0001), with the majority of the detected malaria carriers (65/67) identified as asymptomatic Mozambican nationals transiting through the informal border market from Mozambique to economic hubs within South Africa. Genomic analysis of the malaria isolates revealed a high degree of heterozygosity and limited genetic relatedness between the isolates supporting the hypothesis of limited local malaria transmission within the province. New potential vector breeding sites, potential vector populations with reduced insecticide susceptibility and areas with sub-optimal vector intervention coverage were identified during the entomological investigation. Conclusion: If KwaZulu-Natal is to successfully halt local malaria transmission and prevent the re-introduction of malaria, greater efforts needs to be placed on detecting and treating malaria carriers at both formal and informal border crossings with transmission blocking antimalarials, while ensuring optimal coverage of vector control interventions is achieved.


2012 ◽  
Vol 41 (5) ◽  
pp. 426-434 ◽  
Author(s):  
F. S. M. Barros ◽  
W. P. Tadei ◽  
M. E. Arruda ◽  
Nildimar A. Honório

2020 ◽  
Vol 9 (1) ◽  
Author(s):  
Endashaw Esayas ◽  
Asefa Tufa ◽  
Fekadu Massebo ◽  
Abdulhamid Ahemed ◽  
Ibssa Ibrahim ◽  
...  

Abstract Background Ethiopia has shown notable progress in reducing the burden of malaria over the past two decades. Because of this progress, the country has shifted efforts from control to elimination of malaria. This study was conducted to analyse the malaria epidemiology and stratification of incidence in the malaria elimination setting in eastern Ethiopia. Methods A retrospective study was conducted to analyse the epidemiology of malaria by reviewing the district health office data from 2013 to 2019 in Harari Region. In addition, three years of sub-district level malaria data were used to stratify the malaria transmission intensity. Malaria interventions (Long-lasting insecticidal nets [LLIN] and indoor residual spraying [IRS]) employed were reviewed to analyse the intervention coverage at the Regional level. Descriptive statistics were used to show the malaria transmission in terms of years, season and species of the malaria parasite. Incidence rate per 1000 population and death rate per 1 000 000 population at risk were computed using the total population of each year. Results In the Harari Region, malaria incidence showed a more pronounced declining trend from 2017 to 2019. Plasmodium falciparum, P. vivax and mixed infections accounted for 69.2%, 30.6% and 0.2% of the cases, respectively. There was an increment in malaria intervention coverage and improved malaria diagnosis. In the year 2019 the coverage of LLIN and IRS in the Region were 93.4% and 85.1% respectively. The annual malaria incidence rate dropped from 42.9 cases per 1000 population in 2013 to 6.7 cases per 1000 population in 2019. Malaria-related deaths decreased from 4.7 deaths per 1 000 000 people annually in 2013 to zero, and there have been no deaths reported since 2015. The malaria risk appears to be heterogeneous and varies between districts. A higher number of malaria cases were recorded in Erer and Jenella districts, which constitute 62% of the cases in the Region. According to the sub-district level malaria stratification, there was shrinkage in the malaria transmission map and about 70% of the sub-districts have achieved elimination targets. Conclusions In the Harari Region, malaria morbidity and mortality have been significantly declined. Thus, if this achievement is sustained and scaling-up of the existing malaria prevention and control strategies by focusing on those populations living in the higher malaria transmission districts and sub-districts, planning of malaria elimination from the study area might be feasible.


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