Data from: Haemosporidian prevalence and parasitemia in the tufted titmouse (Baeolophus bicolor)

Haemosporidians are a diverse group of blood parasites that infect terrestrial vertebrates worldwide, but there is variability in parasite prevalence and parasitemia with infections ranging from virtually inconsequential to lethal. In this study, we determined prevalence and parasitemia of avian haemosporidians in the Tufted Titmouse (Baeolophus bicolor; n = 81). Plasmodium and Parahaemoproteus were detected and quantified from blood samples using microscopy, polymerase chain reaction (PCR), and quantitative PCR (qPCR). Thirteen mitochondrial cytochrome b lineages of haemosporidian parasites were found including generalist and specialist lineages, and the data indicate that prevalence is 69.1% (Plasmodium-89.3%; Parahaemoprotues-7.1%; double infection-3.6%). However, parasitemia was low in all infected birds. Seasonally, parasite prevalence varied significantly, although prevalence and parasitemia were not associated with host sex, age, or health. Observations of infection in this naturally infected bird provide details on host susceptibility that are applicable to the understanding of haemosporidian parasites in other avian hosts.血孢子虫（Haemosporidians）是一类广泛分布于全球、可感染陆生脊椎动物的多样化血寄生虫类群，其感染率与虫血症水平存在显著差异，感染后果从几乎无明显临床影响到致命不等。本研究以簇山雀（Tufted Titmouse，学名*Baeolophus bicolor*，样本量n=81）为研究对象，检测并明确了其体内禽源血孢子虫的感染率与虫血症水平。研究通过显微镜镜检、聚合酶链式反应（PCR）与实时定量PCR（qPCR）对血液样本中的疟原虫（*Plasmodium*）及副血变原虫（*Parahaemoproteus*）开展检测与定量分析，共检出13种血孢子虫线粒体细胞色素b谱系，涵盖泛宿主谱系与专性宿主谱系；数据显示整体感染率为69.1%（其中疟原虫占比89.3%，副血变原虫占比7.1%，混合感染占比3.6%）。但所有受感染个体的虫血症水平均较低。季节因素对寄生虫感染率存在显著影响，而感染率与虫血症水平均与宿主的性别、年龄及健康状况无显著关联。本研究针对该自然感染宿主的感染观察结果，可为解析其他鸟类宿主的血孢子虫感染易感性提供重要参考依据。