Venezuela accounted for 55% of the cases and 73% of the malaria deaths in the Americas in 2019. Bolivar state, in the southeast, contributes > 60% of the country's Plasmodium vivax and Plasmodium falciparum cases every year. This study describes the clinical–epidemiological characteristics of clinical malaria patients in this high-transmission area. A prospective study was conducted on patients seeking medical attention in three medical centres in the state capital, Ciudad Bolivar, between June and October 2018. Malaria diagnosis was carried out using microscopy following national standards. Malaria-positive patients were examined for clinical symptoms, and haematological tests were performed at the time of diagnosis. Patients were followed up by telephone to evaluate malaria recurrences. Out of 287 patients, 200 (69.7%) were positive for P. vivax, 69 (24%) for P. falciparum, and 18 (6.3%) had mixed (P. vivax/P. falciparum) infections. Patients' median age was 33 years (IQR 20), 168 (69%) were men, and 40% practiced gold mining as the main occupation. Fever (96.5%), chills (91.3%), and headaches (90.6%) were the most frequent symptoms. At least one symptom associated with severe malaria was observed in 69 out of 161 patients with complete clinical evaluation (42.9%). Plasmodium vivax infections were found in 42 out of 69 (60.9%) severe cases; by contrast, P. falciparum and mixed malaria caused 34.8% (24/69) and 4.4% (3/69) of infections, respectively. Two patients died of cerebral malaria. Mean hemoglobin was lower in the patients infected with P. falciparum than those infected with P. vivax. Regardless of the parasite causing the infection, patients presented high levels of total bilirubin, aminotransferases (AST, ALT), and lactate dehydrogenase (LDH). Out of the 142 patients followed up by phone for three months (49.5% of the 287 patients), 35 (24.7%) reported recurrences. The high malaria prevalence among young male adults practicing gold mining suggests that this occupation is a significant risk factor. The unexpected high prevalence of P. vivax patients with at least one criteria of severe clinical disease is a matter of concern. Whether it is the result of a lack of timely diagnosis and effective treatment should be explored.

中文翻译：

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委内瑞拉南部疟疾患者的临床流行病学特征，这是拉丁美洲的一个关键热点

2019 年，委内瑞拉占美洲疟疾病例的 55%，占疟疾死亡人数的 73%。东南部的玻利瓦尔州每年占该国间日疟原虫和恶性疟原虫病例的 60% 以上。本研究描述了该高传播地区临床疟疾患者的临床流行病学特征。2018 年 6 月至 10 月期间，对在州首府玻利瓦尔城的三个医疗中心就医的患者进行了一项前瞻性研究。 疟疾诊断是按照国家标准使用显微镜进行的。对疟疾阳性患者进行临床症状检查，并在诊断时进行血液学检查。通过电话对患者进行随访以评估疟疾复发情况。在 287 名患者中，200 名 (69.7%) 的 P 阳性。间日疟原虫，69 名（24%）为恶性疟原虫，18 名（6.3%）有混合（间日疟原虫/恶性疟原虫）感染。患者的中位年龄为 33 岁（IQR 20），168 人（69%）为男性，40% 的人以采金业为主要职业。发烧 (96.5%)、寒战 (91.3%) 和头痛 (90.6%) 是最常见的症状。在 161 名经过完整临床评估的患者中，有 69 名 (42.9%) 至少观察到一种与严重疟疾相关的症状。69 例（60.9%）重症病例中有 42 例发现了间日疟原虫感染；相比之下，恶性疟原虫和混合疟疾分别引起 34.8% (24/69) 和 4.4% (3/69) 的感染。两名患者死于脑型疟疾。感染恶性疟原虫的患者的平均血红蛋白低于感染间日疟原虫的患者。不管是什么寄生虫引起感染，患者表现出高水平的总胆红素、转氨酶（AST、ALT）和乳酸脱氢酶（LDH）。在电话随访三个月的 142 名患者中（287 名患者的 49.5%），35 名（24.7%）报告复发。从事金矿开采的年轻男性的疟疾流行率很高，表明这种职业是一个重要的风险因素。具有至少一项严重临床疾病标准的间日疟原虫患者的意外高患病率令人担忧。是否是缺乏及时诊断和有效治疗的结果，值得探讨。从事金矿开采的年轻男性的疟疾流行率很高，表明这种职业是一个重要的风险因素。具有至少一项严重临床疾病标准的间日疟原虫患者的意外高患病率令人担忧。是否是缺乏及时诊断和有效治疗的结果，值得探讨。从事金矿开采的年轻男性的疟疾流行率很高，表明这种职业是一个重要的风险因素。具有至少一项严重临床疾病标准的间日疟原虫患者的意外高患病率令人担忧。是否是缺乏及时诊断和有效治疗的结果，值得探讨。