Infection rates in, and the number of Plasmodium falciparum genotypes carried by Anopheles mosquitoes in Tanzania

1999 ◽  
Vol 93 (6) ◽  
pp. 659-662 ◽  
Author(s):  
L. H. Taylor
2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Marga van de Vegte-Bolmer ◽  
Wouter Graumans ◽  
Rianne Stoter ◽  
Geert-Jan van Gemert ◽  
Robert Sauerwein ◽  
...  

Abstract Background The ability to culture Plasmodium falciparum continuously in vitro has enabled stable access to asexual and sexual parasites for malaria research. The portfolio of isolates has remained limited and research is still largely based on NF54 and its derived clone 3D7. Since 1978, isolates were collected and cryopreserved at Radboudumc from patients presenting at the hospital. Here, procedures are described for culture adaptation of asexual parasites, cloning and production of sexual stage parasites responsible for transmission (gametocytes) and production of oocysts in Anopheles mosquitoes. This study aimed to identify new culture-adapted transmissible P. falciparum isolates, originating from distinct geographical locations. Methods Out of a collection of 121 P. falciparum isolates stored in liquid nitrogen, 21 from different geographical origin were selected for initial testing. Isolates were evaluated for their ability to be asexually cultured in vitro, their gametocyte production capacity, and consistent generation of oocysts. Results Out of 21 isolates tested, twelve were excluded from further analysis due to lack of mature gametocyte production (n = 1) or generation of satisfactory numbers of oocysts in mosquitoes (n = 11). Nine isolates fulfilled selection criteria and were cloned by limiting dilution and retested. After cloning, one isolate was excluded for not showing transmission. The remaining eight isolates transmitted to Anopheles stephensi or Anopheles coluzzii mosquitoes and were categorized into two groups with a reproducible mean oocyst infection intensity above (n = 5) or below five (n = 3). Conclusions These new P. falciparum culture-adapted isolates with reproducible transmission to Anopheles mosquitoes are a valuable addition to the malaria research tool box. They can aid in the development of malaria interventions and will be particularly useful for those studying malaria transmission.


2013 ◽  
Vol 7 (03) ◽  
pp. 269-272 ◽  
Author(s):  
Emília Valadas ◽  
Augusto Gomes ◽  
Ana Sutre ◽  
Sara Brilha ◽  
Afonso Wete ◽  
...  

Introduction: Three major public health problems, tuberculosis, malaria and HIV/AIDS, are widespread in Angola, often as co-infections in the same individual. In 2009, it was assumed that 44,151 new cases of TB occurred in Angola. Interestingly, interventions such as treatment/prevention of malaria appear to reduce mortality in HIV-infected and possibly TB co-infected patients. However, despite the seriousness of the situation, current data on TB and co-infection rates are scarce. This study aimed to characterize all TB cases seen at the Hospital Sanatório de Luanda, and to determine the co-infection rate with HIV and/or malaria. Methodology: This retrospective study collected demographic, diagnostic and clinical data from all patients admitted during 2007. Results: A total of 4,666 patients were admitted, of whom 1,906 (40.8%) were diagnosed with TB. Overall, 1,111 patients (58.3%) were male and most patients (n=1302, 68.3%) were adults (≥14 years). The rate of HIV co-infection was 37.4% (n=712).  Malaria was diagnosed during admission and hospital stay in 714 patients (37.5%), with Plasmodium falciparum the predominant species. Overall mortality was 15.2% (n=290). Conclusions: Because Luanda does not have the infrastructure to perform culture-based diagnosis of TB, confirmation of TB is problematic. The HIV-co-infection rate is high, with 37.4% of patients requiring integrated approaches to address this problem. With more than 1/3 of the TB patients co-infected with malaria, even during the hospital stay, the prevention of malaria in TB patients appears to be an effective way to reduce overall mortality.


2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Yared Debebe ◽  
Sharon Rose Hill ◽  
Göran Birgersson ◽  
Habte Tekie ◽  
Rickard Ignell

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Ana L. Ramírez ◽  
Andrew F. van den Hurk ◽  
Ian M. Mackay ◽  
Annie S. P. Yang ◽  
Glen R. Hewitson ◽  
...  

2021 ◽  
Author(s):  
Marga van de Vegte-Bolmer ◽  
Wouter Graumans ◽  
Rianne Stoter ◽  
Geert-Jan van Gemert ◽  
Robert Sauerwein ◽  
...  

Abstract BackgroundThe ability to culture P. falciparum continuously in vitro has enabled stable access to asexual and sexual parasites for malaria research. The portfolio of isolates has remained limited and research is still largely based on NF54 and its derived clone 3D7. Since 1978, isolates were collected and cryopreserved at Radboudumc from patients presenting at the hospital. Here, procedures are described for culture adaptation of asexual parasites, cloning and production of sexual stage parasites responsible for transmission (gametocytes) and production of oocysts in Anopheles mosquitoes. This study aimed to identify new culture adapted transmissible P. falciparum isolates, originating from distinct geographical locations.ResultsOut of a collection of 121 P. falciparum isolates stored in liquid nitrogen, 21 from different geographical origin were selected for initial testing. Isolates were evaluated for their ability to be asexually cultured in vitro, their gametocyte production capacity, and consistent generation of oocysts. Out of 21 isolates tested, twelve were excluded from further analysis due to lack of mature gametocyte production (n = 1) or generation of satisfactory numbers of oocysts in mosquitoes (n = 11). Nine isolates fulfilled selection criteria and were cloned by limiting dilution and retested. After cloning, one isolate was excluded for not showing transmission. The remaining eight isolates transmitted to A. stephensi or A. coluzzii mosquitoes and were categorized into two groups with a reproducible mean oocyst infection intensity above (n = 5) or below five (n = 3). ConclusionsThese new P. falciparum culture adapted isolates with reproducible transmission to Anopheles mosquitoes are a valuable addition to the malaria research tool box. They can aid in the development of malaria interventions and will be particularly useful for those studying malaria transmission.


2017 ◽  
Vol 5 (1) ◽  
pp. 92
Author(s):  
Vishruti Gandhi Vishruti Gandhi ◽  
Prasad Muley ◽  
Niyati Parikh ◽  
Hardik Gandhi ◽  
Akash Mehta

Background: Malaria is a protozoan disease transmitted by the bite of infected female anopheles mosquitoes is one of the most important parasitic diseases of human with transmission in 109 countries, affecting more than one billion people worldwide. This study was planned to compare the gold standard i.e. peripheral blood smear examination and the newer rapid diagnostic test (malaria plasmodium falciparum/ plasmodium vivax antigen card) to know the diagnostic accuracy of Rapid Diagnostic Test (RDT) kits. Methods: All the suspected cases of WHO defined malaria between 1month to 18 years of age were enrolled in the study.Results: Out of 96 clinically suspected cases of malaria 63 were confirmed by peripheral smear. The age range of participants ranged from 4 months to 17 years. On peripheral smear examination, out of 96 clinically suspected cases, 37 (38.5%) cases were positive for P. vivax, 23 (23.9%) were positive for P. falciparum and 3 (3.1%) were positive for both parasites by microscopy. Sensitivity and specificity of RDT for Plasmodium Vivax is 92.5% and 96.4% respectively. Sensitivity and specificity of RDT for Plasmodium Falciparum is 96.2% and 90%.Conclusions: The rational use of RDTs as a complement to microscopy might give substantial health benefits through earlier treatment, reduction in morbidity and mortality and more rationalized approach for choosing anti-malarial drugs, which in terms may prevent drug resistance.


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