Evolution Characterization and Pathogenicity of an NADC34-like PRRSV Isolated from Inner Mongolia, China.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen that causes severe abortions in sows and high piglet mortality, resulting in huge economic losses to the pig industry worldwide. The emerging and novel PRRSV isolates are clinically and biologically important, as there are likely recombination and pathogenic differences among PRRSV genomes. Furthermore, the NADC34-like strain has become a major epidemic strain in some parts of China, but the characterization and pathogenicity of the latest strain in Inner Mongolia have not been reported in detail. In this study, an NADC34-like strain (CHNMGKL1-2304) from Tongliao City, Inner Mongolia was successfully isolated and characterized, and confirmed the pathogenicity in pigs. The phylogenetic tree showed that this strain belonged to sublineage 1.5 and had high homology with the strain JS2021NADC34. There is no recombination between CHNMGKL1-2304 and any other domestic strains. Animal experiments show that the CHNMGKL1-2304 strain is moderately virulent to piglets, which show persistent fever, weight loss and high morbidity but no mortality. The presence of PRRSV nucleic acids was detected in both blood, tissues, nasal and fecal swabs. In addition, obvious pathological changes and positive signals were observed in lung, lymph node, liver and spleen tissues when subjected to hematoxylin-eosin (HE) staining and immunohistochemistry (IHC). This report can provide a basis for epidemiological investigations and subsequent studies of PRRSV.

Investigation of ABO and RhD blood groups in childbearing age people in rural areas of Yunnan Province / 中华预防医学杂志

The participants in this study were 20-49 years old rural childbearing age people who received the National Free Preconception Health Examination Project (NFPHEP) in Yunnan Province during 2013 to 2019. The proportion of ABO and RhD blood groups among different ethnic groups and different areas were calculated. The proportion of 2 748 131 participants with blood group A phenotype was highest (32.60%), followed by O (30.60%), B (27.33%) and AB (9.47%). In the RhD blood system, the proportion of the RhD positivity (RhD+) and RhD negativity (RhD-) group were 99.29% and 0.71% respectively. The proportions blood groups were significantly different among ethnic groups and areas (all P<0.001). Among 18 ethnic groups with more than 3 000 participants, Yao (42.75%), Bouyei (40.58%) and Dai (40.37%) ethnic groups had higher proportion of blood group O phenotype than other ethnic groups. Wa ethnic groups had highest proportion of the A (40.15%) and AB phenotypes (11.23%). Miao ethnic group (34.70%) and Lahu ethnic group (34.42%) had higher proportion of blood group B phenotype than other ethnic groups. Wa ethnic group had the highest proportion of RhD-group (1.88%). In all 16 prefectures of Yunnan, the proportion of blood group O phenotype was highest in Xishuangbanna Dai Autonomous Prefecture (40.27%). Baoshan city (36.39%), Lincang city (36.22%) and Dali Bai autonomous prefecture (36.06%) had higher proportion of blood group A phenotype than other regions. Diqing Tibetan Autonomous Prefecture (30.83%) and Qujing city (30.48%) had higher proportion of blood group B phenotype than other areas, while Zhaotong city had a highest proportion of blood group AB phenotype (11.19%). The proportion of RhD-group was highest in Honghe hani and Yi nationality autonomous prefecture(1.37%). The A RhD+(39.36%), A RhD-(0.78%), AB RhD+(11.03%), AB RhD-(0.20%) and O RhD-(0.48%) blood groups were higher proportion in Wa ethnic group than in other ethnic groups (P<0.001).