Geographically, Turkey is situated in an area where malaria is very risky. The climatic conditions in the region are suitable for the malaria vector to proliferate. Due to agricultural infrastructural changes, GAP and other similar projects, insufficient environmental conditions, urbanization, national and international population moves, are a key to manage malaria control activities. It is estimated that malaria will be a potential danger for Turkey in the forthcoming years. The disease is located largely in south-eastern Anatolia. The Diyarbakir, Batman, Sanliurfa, Siirt, and Mardin districts are the most affected areas. In western districts, like Aydin and Manisa, an increase in the number of indigenous cases can be observed from time to time. This is due to workers moving from malaria districts to western parts to final work. Since these workers cannot be controlled, the population living in these regions get infected from indigenous cases. There were 84,345 malaria cases in 1994 and 82,096 in 1995, they decreased to 60,884 in 1996 and numbered 35,456 in 1997. They accounted for 36,842 and 20,963 in 1998 and 1999, respectively. In Turkey there are almost all cases of P. vivax malaria. There are also P. vivax and P. falciparum malaria cases coming from other countries: There were 321 P. vivax cases, including 2 P. falciparum ones, arriving to Turkey from Iraq in 1995. The P. vivax malaria cases accounted for 229 in 1996, and 67, cases P. vivax including 12 P. falciparum cases, in 1997, and 4 P. vivax cases in 1998 that came from that country. One P. vivax case entered Turkey from Georgia in 1998. The cause of higher incidence of P. vivax cases in 1995, it decreasing in 1999, is the lack of border controls over workers coming to Turkey. The other internationally imported cases are from Syria, Sudan, Pakistan, Afghanistan, Nigeria, India, Azerbaijan, Malaysia, Ghana, Indonesia, Yemen. Our examinations have shown that none of these internationally imported cases are important in transmitting the diseases. The districts where malaria cases occur are the places where population moves are rapid, agriculture is the main occupation, the increase in the population is high and the education/cultural level is low. Within years, the districts with high malaria cases also differ. Before 1990 Cucurova and Amikova were the places that showed the highest incidence of malaria. Since 1990, the number of cases from south-eastern Anatolia has started to rise. The main reasons for this change are a comprehensive malaria prevention programme, regional development, developed agricultural systems, and lower population movements. The 1999 statistical data indicate that 83 and 17% of all malaria cases are observed in the GAP and other districts, respectively. The distribution of malaria cases in Turkey differs by months and climatic conditions. The incidence of malaria starts to rise in March, reaching its peak in July, August and September, begins to fall in October. In other words, the number of malaria cases is lowest in winter and reaches its peak in summer and autumn. This is not due to the parasite itself, but a climatic change is a main reason. In the past years the comprehensive malaria prevention programme has started bearing its fruits. Within the WHO Roll Back Malaria strategies, Turkey has started to implement its national malaria control projects, the meeting held on March 22, 2000, coordinated the country's international cooperation for this purpose. The meeting considered the aim of the project to be introduced into other organizations. In this regards, the target for 2002 is to halve the incidence of malaria as compared to 1999. The middle--and long-term incidence of malaria will be lowered to even smaller figures. The objectives of this project are as follows: to integrate malaria services with primary health care services to prove more effective studies; to develop early diagnosis and treatment systems, to provide better diagnostic services, and to develop mobile diagnostic ones; to make radical treatment and monitoring patients; to conduct regular active case surveillance studies; to conduct regular vector control studies; to monitor the sensitivity of vectors to insecticides and to provide their alternatives; to design malaria control studies for the specialists of districts; to implement educational programmes among the population and attract it in controlling malaria.
Matched MeSH terms: Malaria, Vivax/prevention & control
After a centenary fight against malaria, Brazil has seen an opportunity for change with the proposal of the malaria elimination policy set by the Brazilian government, in line with malaria elimination policies in other Latin American countries. Brazilian malaria experts regard eliminating malaria by 2030 to be within reach. Herein we evaluated the likelihood that malaria elimination can be accomplished in Brazil through systematic review of the literature on malaria elimination in Brazil and epidemiological analysis. Fifty-two articles referring to malaria eradication/elimination in Brazil were analyzed to identify challenges and technological breakthroughs for controlling malaria. Monthly deaths (1979-2016) and monthly severe malaria cases (1998-2018) were analyzed according to age groups, geographic region and parasite species. As a result, we observed that the declining malaria burden was mostly attributable to a decline in Plasmodium falciparum-malaria. At the same time, the proportional increase of Plasmodium vivax-malaria in comparison with P. falciparum-malaria was notable. This niche replacement mechanism was discussed in the reviewed literature. In addition, the challenges to P. vivax-malaria elimination outnumbered the available technological breakthroughs. Although accumulated and basic information exists on mosquito vector biology, the lack of specific knowledge about mosquito vector taxonomy and ecology may hamper current attempts at stopping malaria in the country. An impressive reduction in malaria hospitalizations and mortality was seen in Brazil in the past 3 decades. Eliminating malaria deaths in children less than 5 years and P. falciparum severe cases may be achievable goals under the current malaria policy until 2030. However, eliminating P. vivax malaria transmission and morbidity seems unattainable with the available tools. Therefore, complete malaria elimination in Brazil in the near future is unlikely.
Matched MeSH terms: Malaria, Vivax/prevention & control
The goal to eliminate malaria from the Asia-Pacific by 2030 will require the safe and widespread delivery of effective radical cure of malaria. In October 2017, the Asia Pacific Malaria Elimination Network Vivax Working Group met to discuss the impediments to primaquine (PQ) radical cure, how these can be overcome and the methodological difficulties in assessing clinical effectiveness of radical cure. The salient discussions of this meeting which involved 110 representatives from 18 partner countries and 21 institutional partner organizations are reported. Context specific strategies to improve adherence are needed to increase understanding and awareness of PQ within affected communities; these must include education and health promotion programs. Lessons learned from other disease programs highlight that a package of approaches has the greatest potential to change patient and prescriber habits, however optimizing the components of this approach and quantifying their effectiveness is challenging. In a trial setting, the reactivity of participants results in patients altering their behaviour and creates inherent bias. Although bias can be reduced by integrating data collection into the routine health care and surveillance systems, this comes at a cost of decreasing the detection of clinical outcomes. Measuring adherence and the factors that relate to it, also requires an in-depth understanding of the context and the underlying sociocultural logic that supports it. Reaching the elimination goal will require innovative approaches to improve radical cure for vivax malaria, as well as the methods to evaluate its effectiveness.
INTRODUCTION: Plasmodium vivax malaria has a wide geographic distribution and poses challenges to malaria elimination that are likely to be greater than those of P. falciparum. Diagnostic tools for P. vivax infection in non-reference laboratory settings are limited to microscopy and rapid diagnostic tests but these are unreliable at low parasitemia. The development and validation of a high-throughput and sensitive assay for P. vivax is a priority.
METHODS: A high-throughput LAMP assay targeting a P. vivax mitochondrial gene and deploying colorimetric detection in a 96-well plate format was developed and evaluated in the laboratory. Diagnostic accuracy was compared against microscopy, antigen detection tests and PCR and validated in samples from malaria patients and community controls in a district hospital setting in Sabah, Malaysia.
RESULTS: The high throughput LAMP-P. vivax assay (HtLAMP-Pv) performed with an estimated limit of detection of 1.4 parasites/ μL. Assay primers demonstrated cross-reactivity with P. knowlesi but not with other Plasmodium spp. Field testing of HtLAMP-Pv was conducted using 149 samples from symptomatic malaria patients (64 P. vivax, 17 P. falciparum, 56 P. knowlesi, 7 P. malariae, 1 mixed P. knowlesi/P. vivax, with 4 excluded). When compared against multiplex PCR, HtLAMP-Pv demonstrated a sensitivity for P. vivax of 95% (95% CI 87-99%); 61/64), and specificity of 100% (95% CI 86-100%); 25/25) when P. knowlesi samples were excluded. HtLAMP-Pv testing of 112 samples from asymptomatic community controls, 7 of which had submicroscopic P. vivax infections by PCR, showed a sensitivity of 71% (95% CI 29-96%; 5/7) and specificity of 93% (95% CI87-97%; 98/105).
CONCLUSION: This novel HtLAMP-P. vivax assay has the potential to be a useful field applicable molecular diagnostic test for P. vivax infection in elimination settings.
Matched MeSH terms: Malaria, Vivax/prevention & control
In spite of more than 30 years of control activities, malaria continues to be the most important parasitic infection in Malaysia, accounting for 39,189 confirmed cases in 1991, giving an annual parasite incidence rate of 2.2 per 1,000 population. Some factors contributing to the continued transmission of malaria are the development of drug resistant Plasmodium falciparum, changes in vector behavior, and ecological changes due to socio-economic reasons. Malaria parasite rates are higher among the Aborigines, land scheme settlers and those in intimate contact with the jungle, like loggers. There has been no substantial change in the proportion of the three common malaria species responsible for infections, P. falciparum, P. vivax, P. malariae and mixed infections accounting for about 70%, 28%, 1% and 1%, respectively of all infections. Drug resistant P. falciparum is unevenly distributed in Malaysia, but based on clinical experience and in vitro drug sensitivity studies, chloroquine resistance is frequently encountered. There has been clinical and laboratory evidence of resistance to sulfadoxine/pyrimethamine combination as well as quinine, but all these have so far been successfully treated with a combination of quinine and tetracycline. The eradication of the disease is impossible in the near future but there is confidence that with better surveillance techniques and the use of alternative control measures like permethrin impregnated bed-nets to complement existing ones, the target of bringing down the annual parasite incidence to 2 per 1,000 population during the Sixth Malaysian Plan period (1991-1995) can be achieved.
Matched MeSH terms: Malaria, Vivax/prevention & control
INTRODUCTION: Transgenic malaria parasites expressing foreign genes, for example fluorescent and luminescent proteins, are used extensively to interrogate parasite biology and host-parasite interactions associated with malaria pathology. Increasingly transgenic parasites are also exploited to advance malaria vaccine development. Areas covered: We review how transgenic malaria parasites are used, in vitro and in vivo, to determine protective efficacy of different antigens and vaccination strategies and to determine immunological correlates of protection. We describe how chimeric rodent parasites expressing P. falciparum or P. vivax antigens are being used to directly evaluate and rank order human malaria vaccines before their advancement to clinical testing. In addition, we describe how transgenic human and rodent parasites are used to develop and evaluate live (genetically) attenuated vaccines. Expert commentary: Transgenic rodent and human malaria parasites are being used to both identify vaccine candidate antigens and to evaluate both sub-unit and whole organism vaccines before they are advanced into clinical testing. Transgenic parasites combined with in vivo pre-clinical testing models (e.g. mice) are used to evaluate vaccine safety, potency and the durability of protection as well as to uncover critical protective immune responses and to refine vaccination strategies.