Department of Pulmonology, University Hospital of Galdakao-Usansolo, Galdakao, Bilbao, Spain.
Department of Pneumology, Hospital Clinic of Barcelona, Barcelona, Spain.
Semin Respir Crit Care Med. 2020 Aug;41(4):509-521. doi: 10.1055/s-0040-1710594. Epub 2020 Jul 6.
Q fever is a zoonotic infectious disease caused by the bacterium. It is an obligate intracellular pathogen with a high infection capacity that proliferates exclusively in an acidified medium, forming a lysosome-like vacuole. It presents a peculiar phenomenon called "antigenic phase variation," produced by a modification in the complexity of the membrane lipopolysaccharides. Q fever can be found worldwide and presents variable clinical features and geographical distribution. It mostly affects people in rural areas who are in contact with animals. The most common type of transmission to humans is via the inhalation of aerosols containing the pathogen, especially those formed from placental derivatives. Wild animals, domestic animals, and ticks are the principal reservoirs.Diagnosis is mainly made by indirect methods such as serology or by direct methods such as microbiological cultures or tests that detect the specific DNA. Typically, there are two clinical presentations: the acute disease, which is more frequent and often asymptomatic, and a persistent focalized infection in 4 to 5% of patients, generally with a poor evolution. Treatment of the acute form in both children and adults consists of administering doxycycline, while persistent focalized infection should be treated with at least two antibiotics, such as doxycycline and hydroxychloroquine. Several measures should be undertaken to minimize exposure among people working with animals or handling birth products. Different vaccines have been developed to prevent infection, though few data are available.
Q 热是一种由细菌引起的人畜共患传染病。它是一种严格的细胞内病原体，具有高感染能力，仅在酸化介质中增殖，形成类似于溶酶体的空泡。它表现出一种特殊的现象，称为“抗原相变异”，这是由膜脂多糖复杂性的改变引起的。Q 热可在全球范围内发现，具有不同的临床特征和地理分布。它主要影响接触动物的农村地区人群。人类最常见的传播途径是吸入含有病原体的气溶胶，特别是那些由胎盘衍生物形成的气溶胶。野生动物、家畜和蜱是主要的宿主。诊断主要通过间接方法（如血清学）或直接方法（如微生物培养或检测特定 DNA 的试验）进行。通常有两种临床表现：急性疾病更为常见且常无症状，4%至 5%的患者会出现持续性局灶性感染，通常预后较差。儿童和成人急性形式的治疗包括使用多西环素，而持续性局灶性感染应至少使用两种抗生素，如多西环素和羟氯喹。应采取一些措施来尽量减少与动物接触或处理分娩产品的人群的暴露。已经开发了几种疫苗来预防感染，但可用的数据很少。
