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1.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1372097

ABSTRACT

Paciente de 35 años, G3P3, indígena, que presenta un parto en casa. Al momento de su admisión con fiebre de 39°C y deterioro neurológico. Se sospechó un shock mix-to, el cual no respondió al manejo en la unidad de cuida-dos intensivos. Paciente fallece al poco tiempo de ser admitida. Autopsia revela múltiples lesiones, en diversos órganos, compatibles con una infección por Plasmodium falciparum. (provisto por Infomedic International)


35-year-old female patient, G3P3, indigenous, presenting with home delivery. On admission with fever of 39°C and neurological deterioration. Mixed shock was suspected, which did not respond to intensive care unit management. Patient died shortly after admission. Autopsy revealed mul-tiple lesions in various organs, compatible with Plasmo-dium falciparum infection. (provided by Infomedic International)

2.
Biomédica (Bogotá) ; 42(1): 127-135, ene.-mar. 2022. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1374512

ABSTRACT

Resumen Introducción. La malaria gestacional, definida como la presencia de Plasmodium spp. en sangre periférica materna o el hallazgo del parásito en la placenta, es considerada un importante problema de salud pública en las regiones tropicales y subtropicales. Objetivo. Determinar la frecuencia de casos de malaria gestacional diagnosticados en Ecuador entre 2015 y 2018. Materiales y métodos. Se hizo un estudio descriptivo, retrospectivo y transversal. Resultados. Se determinaron 46 casos de malaria gestacional en el período evaluado, 25 por Plasmodium falciparum y 21 por Plasmodium vivax, siendo el 2018 el año con más casos. En cuanto a las variables de edad y trimestre de gestación, prevalecieron en el grupo de 20 a 29 años (46 %) y en el segundo trimestre (37 %). Solo se observó una diferencia significativa entre los casos por año y la especie parasitaria. Conclusión. La malaria gestacional en Ecuador ha aumentado en los últimos cinco años, por lo que es importante informar a las mujeres en estado de gravidez sobre las medidas preventivas para evitar el contagio con el parásito, dadas las graves consecuencias que conlleva para ellas y sus hijos.


Abstract Introduction: Gestational malaria, defined as the presence of Plasmodium spp. in maternal peripheral blood or in the placenta, is considered an important public health problem in tropical and subtropical regions. Objective: To determine the frequency of gestational malaria cases diagnosed in Ecuador between 2015 and 2018. Materials and methods: We conducted a descriptive, retrospective, and cross-sectional study. Results: There were 46 cases of gestational malaria between 2015 and 2018: 25 caused by Plasmodium falciparum and 21 by Plasmodium vivax. The year with the most cases in this period was 2018. The age group most affected was 20 to 29 years old with 21 cases (46%). Prevalence was found to be highest in the second trimester of pregnancy with 17 cases (37%). A significant difference was only observed between cases per year and parasitic species. Conclusion: The prevalence of gestational malaria in Ecuador increased in the last five years. Therefore, it is important to inform pregnant women about preventive measures to avoid infection given its serious consequences both for the mother and her unborn child.

3.
Biomédica (Bogotá) ; 42(1): 147-158, ene.-mar. 2022. tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1374514

ABSTRACT

Resumen Introducción. En Perú, la microscopía óptica con gota gruesa continúa utilizándose en el seguimiento de los pacientes con malaria o paludismo. Esta prueba es sencilla, pero requiere de equipamiento microscópico y personal idóneo que realice la lectura de las muestras. Los estudios sugieren que la prueba rápida OptiMAL-IT™ es una opción para dicho seguimiento. Objetivo. Evaluar la efectividad de OptiMAL-IT™ como test de seguimiento en pacientes con malaria en áreas endémicas del Perú. Materiales y métodos. Se hizo un estudio observacional, transversal y analítico de pruebas diagnósticas en pacientes con malaria. Se seleccionó a todos los pacientes que cumplían con los criterios de inclusión, procedentes de diferentes establecimientos de salud de los departamentos peruanos de San Martín y Loreto. El diagnóstico se hizo mediante microscopía óptica con gota gruesa y la prueba rápida de diagnóstico inmunocromatográfico OptiMAL-IT™ en los días 2, 3, 7 y 14 para Plasmodium vivax y hasta el día 21 de seguimiento para Plasmodium falciparum. Se calculó el porcentaje de los correctamente clasificados y los valores predictivos, y se compararon los resultados de la selva occidental y la selva oriental mediante ji al cuadrado o prueba exacta de Fisher. Resultados. Se registraron 262 pacientes de San Martín y 302 de Loreto. Los porcentajes correctamente clasificados y el valor predictivo negativo fueron superiores a 92,0 y 93,0 %, respectivamente, a partir del tercer día de seguimiento; no se encontraron diferencias estadísticas en los resultados obtenidos en la Amazonía occidental y los de la oriental. Conclusiones. La prueba OptiMAL-IT™ sería efectiva como test de seguimiento en los pacientes con diagnóstico de malaria en áreas endémicas del Perú.


Abstract Introduction: In Peru, optical microscopy with the thick smear test continues to be performed for the follow-up of malaria patients. This test is simple but it requires microscopic equipment and suitable staff to perform the reading of the samples. Studies suggest that the rapid OptiMAL-IT™ test is an option for follow-up. Objective: To evaluate the effectiveness of OptiMAL-IT™ as a follow-up test in malaria patients in endemic areas of Perú. Materials and methods: We conducted an observational, analytical cross-sectional study of diagnostic tests performed in patients with malaria. We selected all the patients attending different health facilities in the Peruvian departments of San Martín and Loreto who met the inclusion criteria. Optical microscopy with thick smear and OptiMAL-IT™ was used on days 2, 3, 7, and 14 for Plasmodium vivax and until day 21 of follow-up for Plasmodium falciparum. Percentages of correctly classified samples and predictive values were calculated, and the results were compared between the western jungle and the eastern jungle using Chi2 or Fisher's exact tests. Results: We registered 262 patients from San Martín and 302 from Loreto. The percentage of correctly classified cases and the negative predictive value were higher than 92.0% and 93,0%, respectively, from the third day of follow-up; no statistical differences were found in the results obtained from the western jungle and those from the eastern jungle. Conclusions: The OptiMAL-IT™ test would be effective as a follow-up test in patients diagnosed with malaria in endemic areas of Perú.

4.
Rev. Eugenio Espejo ; 16(1): 71-80, 20220111.
Article in Spanish | LILACS | ID: biblio-1353005

ABSTRACT

Objetivo. Determinar el estado actual de la prevalencia de Plasmodium en pacientes febriles que acuden al Hospital Básico Franklin Tello Nuevo Rocafuerte, cantón Aguarico, comparando con los datos de otros estudios epidemiológicos de la misma zona y la frontera con el vecino país de Perú. Métodos. Se realizó un estudio observacional descriptivo, retrospectivo de prevalencia. Desde 2011-2015 se recogieron 2.668 muestras de sangre capilar correspondientes al 55,04% de la población total del cantón Aguarico. Se empleó la técnica Gota Gruesa y Frotis coloreados con Giemsa para determinar positividad de Plasmodium. Resultados. El rango de variación de la prevalencia en los pobladores de las comunidades investigadas osciló entre 2,38% y 28,57%, detectándose mayor prevalencia en el sexo masculino (50,56 %). Estos hallazgos son similares a los estudios previos realizados entre 1992-1995, en la misma región del Aguarico. El Riesgo Relativo es (RR) es de 1,36 y el Odds Ratio (OR) fue de 1,71, siendo mayor el riesgo a desarrollar la enfermedad en los positivos. Conclusiones. Los datos de la investigación confirman la presencia de un foco autóctono de malaria producida por Plasmodium vivax en la selva amazónica ecuatoriana, excepto 2 casos de P. falciparum importados de Perú. Los casos diagnosticados clínicamente y mediante la técnica de la Gota Gruesa, fueron tratados con medicación antipalúdica con excelente adherencia al medicamento.


Objective. To determine the status of the prevalence of Plasmodium in febrile patients who attend the Franklin Tello Nuevo Rocafuerte Basic Hospital, Aguarico town, comparing the results obtained with data from other epidemiological studies in the same area, and places near the border with Peru. Methods. A descriptive, retrospective, observational study of prevalence was carried out. From 2011-2015 2,668 capillary blood samples were collected corresponding to 55.04% of the total population of the Aguarico town. The Thick Drop and Giemsa-stained smear technique was used to determine Plasmodium positivity. Results. The range of variation of the prevalence in the inhabitants of the investigated communities ranged between 2.38% and 28.57%, detecting a higher prevalence in males (50.56%). These findings are like previous studies carried out between 1992-1995, in the same Aguarico region. The Relative Risk (RR) is 1.36 and the Odds Ratio (OR) was 1.71, with the risk of developing the disease being greater in the positives. Conclusions. The research data confirm the presence of an autochthonous focus of malaria produced by Plasmodium vivax in the Ecuadorian Amazon rainforest, except for 2 cases of P. falciparum imported from Peru. The cases diagnosed clinically and using the thick gout technique were treated with antimalarial medication with excellent adherence to the medication.


Subject(s)
Humans , Male , Female , Prevalence , Amazonian Ecosystem , Malaria , Plasmodium vivax , Indigenous Peoples , Antimalarials
5.
Article in Chinese | WPRIM | ID: wpr-913060

ABSTRACT

The RTS,S/AS01 is a subunit malaria vaccine against the pre-erythrocytic stage of Plasmodium falciparum. After over 30 years of research and development and clinical trials, this vaccine has been recommended by the WHO for use among children living in highly malaria endemic areas. Although the RTS, S/AS01 vaccine suffers from problems of a low protective efficacy (about 30%), need of four doses and short duration of protective immunity, this malaria vaccine is expected to save tens of thousands of children’s lives, and avoid tens of millions of malaria cases annually, because there have been tens of thousands of childhood deaths due to malaria recently. The introduction of the RTS, S/AS01 vaccine is therefore, widely accepted as a milestone in the history of battle against malaria, which brings a hope to contain malaria and even eventually eliminate malaria. Although there are still multiple challenges in the development of a satisfactory malaria vaccine, the success of the RTS, S/AS01 malaria greatly facilitates the progress towards the development of parasitic disease vaccines, and a more perfect malaria vaccine deserves expectations.

6.
Article in Chinese | WPRIM | ID: wpr-913059

ABSTRACT

On October, 2021, the WHO announced the recommendation of RTS, S/AS01 for use among children living in moderately and highly malaria-endemic areas, which receives global attention. Here, the history of RTS, S/AS01 vaccine development and its role in malaria control are described.

7.
Article in Chinese | WPRIM | ID: wpr-913058

ABSTRACT

Vaccination is one of the most effective intervention for the containment and elimination of infectious diseases. Recently, the world’s first malaria vaccine RTS, S/AS01 was approved by WHO for use among children living in moderately and highly malaria endemic areas of Africa, which brings a hope for the research and development of malaria vaccines. Here, we review the current status of malaria vaccines development and provide a perspective on the development of next-generation malaria vaccines, so as to provide insights into the successful development of malaria vaccines.

8.
Article in Chinese | WPRIM | ID: wpr-913057

ABSTRACT

RTS, S/AS01 vaccine has recently been recommended by the WHO for large-scale uses in malaria-endemic areas, which is a milestone in the history of the fight against parasitic infections. Nevertheless, RTS, S/AS01 vaccine is not perfect. Hereby, the shortages of RTS, S/AS01 malaria vaccine were discussed, and the potential challenges during the research and development of next-generation malaria vaccines were analyzed.

9.
Article in Chinese | WPRIM | ID: wpr-913056

ABSTRACT

This paper describes the safety, efficacy and operability of the world’s first malaria vaccine (RTS, S/AS01) in latest field pilot studies and the recommendations from the WHO expert group for its use. In addition, further studies to examine the associations of inoculation rate and full-dose rate with the reduction in morbidity and mortality of malaria among target children and explore the scientific evidence for seasonable preventive vaccination with 5 doses and more among children at ages of below 5 years are recommended.

10.
Frontiers of Medicine ; (4): 10-16, 2022.
Article in English | WPRIM | ID: wpr-929200

ABSTRACT

Malaria remains a global health challenge, although an increasing number of countries will enter pre-elimination and elimination stages. The prompt and precise diagnosis of symptomatic and asymptomatic carriers of Plasmodium parasites is the key aspect of malaria elimination. Since the launch of the China Malaria Elimination Action Plan in 2010, China has formulated clear goals for malaria diagnosis and has established a network of malaria diagnostic laboratories within medical and health institutions at all levels. Various external quality assessments were implemented, and a national malaria diagnosis reference laboratory network was established to strengthen the quality assurance in malaria diagnosis. Notably, no indigenous malaria cases have been reported since 2017, but the risk of re-establishment of malaria transmission cannot be ignored. This review summarizes the lessons about malaria diagnosis in the elimination phase, primarily including the establishments of laboratory networks and quality control in China, to better improve malaria diagnosis and maintain a malaria-free status. A reference is also provided for countries experiencing malaria elimination.


Subject(s)
China/epidemiology , Clinical Laboratory Techniques , Global Health , Humans , Laboratories , Malaria/prevention & control
11.
Article in Chinese | WPRIM | ID: wpr-923783

ABSTRACT

Objective To analyze and compare the epidemiological characteristics of imported malaria in Jiaozuo City before and after malaria elimination, so as to provide insights into the malaria surveillance during the post-elimination stage and prevention of re-establishment of imported malaria. Methods Data pertaining to the epidemic situation and individual investigation of malaria in Jiaozuo City before (from 2010 to 2016) and after malaria elimination (from 2017 to November, 2020) were captured from the National Notifiable Disease Reporting System and the Information System for Parasitic Diseases Control and Prevention of Chinese Center for Disease Control and Prevention and were analyzed statistically. Results A total of 74 imported malaria cases were reported in Jiaozuo City from 2010 to 2021. Imported cases were predominantly Plasmodium falciparum malaria cases in Jiaozuo City before and after malaria elimination, and there was no significant difference in the proportion of malaria parasite species (χ2 = 0.234, P > 0.05). The imported malaria cases was predominantly reported in Wuzhi County, and was identified in overseas male farmers and businessmen at ages of 20 to 59 years, while the greatest number of imported malaria cases was reported in June and December before and after malaria elimination. The imported malaria cases predominantly acquired malaria parasite infections in sub-Saharan African countries; however, the proportion of imported malaria cases returning from Southeast Asian counties increased after malaria elimination than before malaria elimination (χ2 = 5.989, P < 0.05). The longest duration from onset to definitive diagnosis of malaria reduced from 27 days before malaria elimination to 18 days after malaria elimination, and the median duration reduced from 3 days to 2 days, while the proportion of definitive diagnosis of malaria increased from 60.47% before malaria elimination to 83.87% after malaria elimination (χ2 = 4.724, P < 0.05). In addition, the proportion of malaria cases definitively diagnosed and reported by medical institutions increased after malaria elimination than before malaria elimination (χ2 = 5.406, P < 0.05). Conclusions The imported malaria patients were predominantly P. falciparum malaria cases in Jiaozuo City during 2010 to 2021, and the patient’s medical care-seeking awareness and medical staff’s diagnosis and treatment ability have improved after malaria elimination. It is necessary to strengthen and improve malaria surveillance and response system and prevent the re-establishment of overseas imported malaria.

12.
Article in Chinese | WPRIM | ID: wpr-923779

ABSTRACT

Objective To investigate the health-seeking behaviors of imported malaria cases after returning to China, and to investigate the factors affecting the time to initial diagnosis, so as to provide the scientific evidence for early identification of imported malaria cases and prevention of severe cases development and secondary transmission. Methods The individual demographic features, and the disease onset and the time to initial diagnosis of imported malaria cases in Jiangsu Province in 2019 were captured from the National Notifiable Disease Report System and the Information Management System for Parasitic Disease Control in China. The characteristics of health-seeking behaviors and epidemiological features of imported malaria cases were descriptively analyzed, and the factors affecting the time to initial diagnosis of imported malaria cases after returning to China were identified using multivariate logistic regression analysis. Results A total of 244 imported malaria cases were reported in Jiangsu Province in 2019, and the time to initial diagnosis of the cases were 1-12 days, with mean time of (1.53 ± 1.65) days, with median time of one day. The highest number of malaria cases seeking healthcare services were found on the day of developing primary symptoms (76 cases, 31.1%), followed by on the second day (68 cases, 27.9%), on the third day (46 cases, 18.9%), and 54 cases (22.1%) received initial diagnosis 3 days following presence of primary symptoms, including 3 cases with initial diagnosis at more than one week. High proportions of imported malaria cases with a delay in the time to initial diagnosis were seen in migrant workers who returned to China in January (14 cases, 5.7%) and December (13 cases, 5.3%) and those aged between 41 and 50 years (32 cases, 13.1%). Multivariate logistic regression analysis showed relative short time to initial diagnosis among imported malaria cases returning to China on March [odds ratio (OR) = 0.16, P = 0.03, 95% confidence interval (CI): (0.03, 0.85)] and those with a history of overseas malaria parasite infections [OR = 0.36, P = 0.001, 95% CI: (0.19, 0.67)]. Conclusions Timely health-seeking behaviors should be improved among imported malaria cases in Jiangsu Province, patients with a history of overseas malaria infections require faster health-seeking activities.

13.
Article in Chinese | WPRIM | ID: wpr-923778

ABSTRACT

Objective To create a risk assessment indicator system for re-establishment of imported malaria. Methods The risk assessment indicator system for re-establishment of imported malaria was preliminarily constructed through literature review and thematic discussions. A total of 26 malaria control experts were selected to carry out a two-round Delphi consultation of the indicator system. The active coefficient, authority coefficient and coordination coefficient of the experts and the coefficient of variation on each indicator were calculated for indicator screening and the weight of each indicator was calculated. The reliability of the indicator system was evaluated using Cronbach’s coefficient α, and the content validity of the indicator system was evaluated using the authority coefficient of the expert, while the structural validity of the indicator system was evaluated using Kaiser-Meyer-Olkin (KMO) test and factor analysis. Results Two rounds of Delphi expert consultations were completed by 23 malaria control experts, and a risk assessment indicator system for re-establishment of imported malaria was constructed, including 3 primary indicators, 7 secondary indicators, and 21 tertiary indicators. The active coefficient (100.00% vs. 88.46%; P < 0.01) and coordination coefficient of the expert (0.372 vs. 0.286; P < 0.01) were significantly greater in the second round of the Delphi expert consultation than in the first round. After the second round of the Delphi expert consultation, the authority coefficient of the experts ranged from 0.757 to 0.930 on each indicator, and the coefficients of variation were 0.098 to 0.136, 0.112 to 0.276 and 0.139 to 0.335 for the primary, secondary and tertiary indicators, respectively. The overall Cronbach’s coefficient α of the indicator system was 0.941, and there were significant differences in the KMO values for primary (KMO value = 0.523; χ2 = 18.192, P < 0.05), secondary (KMO value = 0.694, χ2 = 51.499, P < 0.01) and tertiary indicators (KMO value = 0.519; χ2 = 477.638, P < 0.01), while the cumulative contribution rate of six principal components in the tertiary indicators was 84.23%. The normalized weights of three primary indicators of the source of infection, transmission condition and control capability were 0.337, 0.333 and 0.329, and the three secondary indicators with the greatest normalized weights included the number of imported cases and malaria parasite species (0.160), introduction of imported cases in China and medical care seeking (0.152), vector species and density (0.152), while the five tertiary indicators with the greatest normalized weights included the malaria parasite species of imported cases (0.065), vector populations (0.064), and the time interval from onset to medical care seeking (0.059), number of imported cases (0.056), and the time interval from medical care seeking to definitive diagnosis (0.055). Conclusions A risk assessment indicator system for re-establishment of imported malaria is successfully created, which provides insights into the assessment of the risk of re-establishment of imported malaria and management of key high-risk factors in malaria-eliminated areas.

14.
Article in Chinese | WPRIM | ID: wpr-923772

ABSTRACT

As the first country that has been certified malaria-free in the WHO Western Pacific Region for more than 3 decades, China should share its successful experiences of malaria control and provide globally recognized anti-malaria products by making full uses of its advantages in provision and production capacity of artemisinin raw materials, to fill the gaps of international demands for mosquito nets, rapid diagnostic reagents and antimalarial compounds. Increasing the investment of research and development of antimalarial products, building overseas bases for artemisinin raw material production, establishing international regulatory authority and promoting the local production of antimalarial products are needed to further promote the internationalization of Chinese antimalarial products, so as to achieve the equity and accessibility of Chinese antimalarial products in highburden regions for malaria.

15.
Article in Chinese | WPRIM | ID: wpr-923771

ABSTRACT

Malaria caused a heavy disease, economic and social burdens in China. Following 70-year concerted efforts, China has been awarded a malaria-free certification by the WHO on June 2021. This paper summarizes the control strategies of Anopheles vectors from malaria control to post-elimination stages in China, emphasizes the risk of imported malaria cases caused re-transmission and the challenges of Anopheles control after malaria elimination in China. Sustainable and precise vector control is still required in China during the post-elimination stage to consolidate malaria elimination achievements in the country. In addition, China’s innovative vector control strategies, technologies and experiences will contribute to global malaria control and elimination programs.

16.
Article in Chinese | WPRIM | ID: wpr-923770

ABSTRACT

China was certificated malaria-free by WHO in 2021 and has continued to maintain malaria elimination. However, there are still huge challenges in malaria control in the border regions between Yunnan Province, China and Myanmar due to lack of geographic barriers and frequent cross-border travel. Hereby, we review the direction contributions of the Global Fund Malaria Program implemented by Health Poverty Action (HPA), an international non-governmental organization (NGO), to malaria elimination in China, and analyze the challenges of malaria control caused by external environmental factors, such as COVID-19, in regions where the Global Fund Malaria Program is implemented. In addition, some suggestions are proposed for cross-border collaboration on malaria control.

17.
Article in Chinese | WPRIM | ID: wpr-923769

ABSTRACT

China was certified malaria-free by the WHO on June, 2021. Nevertheless, there are thousands of overseas imported malaria cases annually in China, and there are deaths of imported malaria cases reported every year in the country. In addition, there are secondary cases of imported malaria, and malaria vectors remain in regions where malaria were formerly endemic, resulting in a high risk of local transmission of imported malaria in eliminated regions in China. This article analyzes the risk of malaria control and the challenges of malaria surveillance and response during the post-elimination stage in China, and proposes some suggestions for future priorities.

18.
Article in Chinese | WPRIM | ID: wpr-923768

ABSTRACT

On June 2021, China was certified malaria-free by WHO. However, the global number and death of malaria cases have recently increased, and the malaria vectors will continue to inhabit in China, resulting in a high difficulty in consolidation of malaria elimination achievements. Hereby, we analyze the current challenges and propose the future priority of the national malaria control program in China, in order to provide insights into prevention of re-establishment of imported malaria in the country.

19.
Article in Chinese | WPRIM | ID: wpr-923355

ABSTRACT

Objective To analyze and evaluate the clinical characteristics of imported falciparum malaria cases and the antimalarial effect of artemisinin-based drugs, to promote rational and standardized drug use, and to improve the clinical cure rate of falciparum malaria. Methods A total of 116 imported cases of falciparum malaria admitted to the provincial malaria designated hospital in Wuhan were collected, and the clinical characteristics of the patients and use of artemisinin, and the therapeutic effects of the artemisinin-based drugs were retrospectively analyzed. Results The clinical manifestations of imported falciparum malaria were complicated and varied and had many complications, including mainly fever, anorexia, anemia, and jaundice, etc. The symptoms were alleviated or disappeared after treatment with artemisinin, without obvious adverse drug reactions. The median time of fever reduction was 2 days, the median time of Plasmodium becoming negative was 3 days, and the median time of clinical symptom relief was 3 days. 109 cases of common falciparum malaria were treated by oral artemisinin compound or artesunate injection combined with oral artemisinin compound, including 30 cases of oral artemisinin compound treatment for 1 to 4 days (1 case relapsed) and 79 cases of artesunate injection combined with oral artemisinin compound for 4 to 6 days (4 cases relapsed). Seven severe cases were cured after long-term and high-dose treatment with artesunate injection combined with oral multiple artemisinin compounds, and the total cure rate was 95.69% (111/116). Conclusion The present study demonstrates that the treatment of falciparum malaria by oral injection of artemisinin is safe and effective, and the cure rate is high. However, some patients have recurrence of the malaria parasite after stopping artemisinin drugs. It is necessary to ensure the use of artemisinin-based drugs in a “standardized, full-process, and adequate” way to contain the risk of severe illness and drug resistance.

20.
Article in English | LILACS-Express | LILACS | ID: biblio-1360794

ABSTRACT

ABSTRACT Malaria is the most important vector-borne disease in the world and a challenge for control programs. In Brazil, 99% of cases occur in the Amazon region. In the extra-Amazonian region, a non-endemic area, epidemiological surveillance focuses on imported malaria and on autochthonous outbreaks, including cases with mild symptoms and low parasitemia acquired in the Atlantic Forest biome. In this scenario, cases are likely to be underreported, since submicroscopic parasitemias are not detected by thick blood smear, considered the reference test. Molecular tests are more sensitive, detecting asymptomatic individuals and mixed infections. The aim of this study was to propose a more efficient alternative to detect asymptomatic individuals living in areas of low malaria endemicity, as they are reservoirs of Plasmodium that maintain transmission locally. In total, 955 blood samples from residents of 16 municipalities with autochthonous malaria outbreaks in the Sao Paulo State were analyzed; 371 samples were collected in EDTA tubes and 584 in filter paper. All samples were initially screened by a genus-specific qPCR targeting ssrRNA genes (limit of detection of 1 parasite/µL). Then, positive samples were subjected to a nested PCR targeting ssrRNA and dihydrofolate reductase-thymidylate synthase genes (limit of detection of 10 parasites/µL) to determine Plasmodium species. The results showed a statistically significant difference (K = 0.049; p < 0.0001) between microscopy positivity (6.9%) and qPCR (22.9%) for EDTA-blood samples. Conversely, for samples collected in filter paper, no statistical difference was observed, with 2.6% positivity by thick blood smear and 3.1% for qPCR (K = 0.036; p = 0.7). Samples positive by qPCR were assayed by a species-specific nested PCR that was in turn positive in 26% of samples (16 P. vivax and 4 P. malariae ). The results showed that molecular protocols applied to blood samples from residents in areas with autochthonous transmission of malaria were useful to detect asymptomatic patients who act as a source of transmission. The results showed that the genus-specific qPCR was useful for screening positives, with the subsequent identification of species by nested PCR. Additional improvements, such as standardization of blood plotting on filter paper and a more sensitive protocol for species determination, are essential. The qPCR-based algorithm for screening positives followed by nested PCR will contribute to more efficient control of malaria transmission, offering faster and more sensitive tools to detect asymptomatic Plasmodium reservoirs.

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