Blastocystis is a common enteric protist that is linked to intestinal and extra-intestinal diseases. At least 24 subtypes (STs) have been described, with the main colonization of ST1–ST4 in humans. In our attempt to determine the distribution of Blastocystis STs in Olsztyn and surroundings in northeastern Poland, 319 stool samples from volunteers were subjected to copro-ELISA and PCR testing. Positive findings were identified in 77, 48, and 46 of the samples via copro-ELISA, PCR, and sequencing, respectively. Blastocystis colonization was not associated with gender or dwelling place but was statistically higher in people age 60–69 yr (32.6%). Five STs (ST1–ST4, ST7) were identified, in which ST3 (37%) was most prevalent, followed by ST2 (19.6%), ST1 (17.4%), ST4 (13%), and ST7 (8.7%). The current study revealed a similar rate of microorganism colonization in Polish volunteers compared to other developed countries, without significant differences in gender and dwelling place. Significant statistical differences were found in different age groups, where Blastocystis was highly detected in elderly people. In the current study, PCR was the most plausible method based on the sequencing results.

囊胚是一种常见的肠道原生生物，与肠道和肠外疾病有关。至少有 24 种亚型 (ST) 已被描述，其中 ST1-ST4 主要在人类中定植。为了确定波兰东北部 Olsztyn 和周边地区囊胚STs的分布，我们对来自志愿者的 319 份粪便样本进行了 copro-ELISA 和 PCR 检测。分别通过 copro-ELISA、PCR 和测序在 77、48 和 46 个样本中确定了阳性结果。囊胚定植与性别或居住地无关，但在 60-69 岁的人群中具有统计学意义（32.6%）。确定了五个 ST（ST1–ST4、ST7），其中 ST3 (37%) 最普遍，其次是 ST2 (19.6%)、ST1 (17.4%)、ST4 (13%) 和 ST7 (8.7%)。目前的研究表明，与其他发达国家相比，波兰志愿者的微生物定植率相似，性别和居住地没有显着差异。不同年龄组间存在显着的统计学差异，其中囊胚病在老年人群中检出率较高。在目前的研究中，基于测序结果，PCR 是最合理的方法。