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The current outbreak of coronavirus disease-2019 (COVID-19) poses unprecedented challenges to global health 1 . The new coronavirus responsible for this outbreak-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-shares high sequence identity to SARS-CoV and a bat coronavirus, RaTG13 2 . Although bats may be the reservoir host for a variety of coronaviruses 3,4 , it remains unknown whether SARS-CoV-2 has additional host species. Here we show that a coronavirus, which we name pangolin-CoV, isolated from a Malayan pangolin has 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S proteins, respectively. In particular, the receptor-binding domain of the S protein of pangolin-CoV is almost identical to that of SARS-CoV-2, with one difference in a noncritical amino acid. Our comparative genomic analysis suggests that SARS-CoV-2 may have originated in the recombination of a virus similar to pangolin-CoV with one similar to RaTG13. Pangolin-CoV was detected in 17 out of the 25 Malayan pangolins that we analysed. Infected pangolins showed clinical signs and histological changes, and circulating antibodies against pangolin-CoV reacted with the S protein of SARS-CoV-2. The isolation of a coronavirus from pangolins that is closely related to SARS-CoV-2 suggests that these animals have the potential to act as an intermediate host of SARS-CoV-2. This newly identified coronavirus from pangolins-the most-trafficked mammal in the illegal wildlife trade-could represent a future threat to public health if wildlife trade is not effectively controlled.

Since 2013, the second outbreak of peste des petits ruminants (PPR) caused by Peste des petits ruminants virus (PPRV) has spread over more than 20 provinces, municipalities, and autonomous regions in China, resulting in major economic losses for livestock industry. In 2014, we encountered a clinical PPR case on a goat farm in Guangdong province, southern China. The complete genome of this PPRV strain, named CH/GDDG/2014, was sequenced to determine its similarities and differences with other strains. The CH/GDDG/2014 genome comprised 15,954 nucleotides (six nucleotides more than classical PPRVs identified before 2013, but complying with the rule of six) with six open reading frames encoding nucleocapsid protein, phosphoprotein, matrix protein, fusion protein, hemagglutinin, and large polymerase protein, respectively. The whole-genome-based alignment analysis indicated that CH/GDDG/2014 had the most proximate consensus (99.8 %) to China/XJYL/2013 and the least consensus (87.2 %) to KN5/2011. The phylogenetic analysis showed that CH/GDDG/2014 was clustered in one branch (lineage IV) with other emerging strains during the second outbreak. This study is the first report describing the whole-genome sequence of PPRV in Guangdong province, southern China and also suggests the PPR outbreak may be closely related to illegal cross-regional importation of goats.

For the worldwide pig industries, porcine circovirus type 2 (PCV2) is an economically important pathogen. At present, the prevalence of PCV2 is common in Chinese swine herds. However, there is little information on PCV2 prevalence in non-porcine animals in China, such as bovids. Therefore, the goal of this study is to obtain the firsthand prevalence data of PCV2 in bovids in China. Two hundred and eighty serum and muscle samples from dairy cows (n = 180), buffalo (n = 50), and yellow cattle (n = 50) were analyzed by PCR. The detection results show that PCV2 infections (16 %, 8/50) only exist in buffaloes. In addition, there are different PCV2 viral DNAs identified by differential PCR in the same buffalo sample. Nucleotide sequencing and phylogenetic analysis results based on partial ORF1 and ORF2 sequences suggest that PCV2 strains have genetic diversity in buffaloes and they are divided into three different genotypes (PCV2b, PCV2d, and PCV2e, respectively). Moreover, to our knowledge, the PCV2d and PCV2e genotypes have not been previously reported in bovids. Through this study, the firsthand data of PCV2 prevalence in bovids in China was documented.

Complete genome characterization of porcine circovirus type 2 (PCV2) for bovid origins was still unclear in China. Therefore, in this study, PCV2 full-length genome of buffalo-origin was amplified and analyzed using PCR, DNAStar and MEGA 5.1. Genome size of three distinct PCV2 strains (buffalo1, buffalo2 and buffalo3) was 1767 bp (48.56% G+C), 1767 bp (48.67% G+C) and 1768 bp (48.08% G+C), respectively. At the nucleotide level, their identity varied from 95% to 96% for complete genome, from 97% to 97.8% for ORF1, and from 90.6% to 94.4% for ORF2. At the amino acid level, their identity varied from 98.7% to 99% for ORF1, and from 88% to 94.9% for ORF2. Online Blast analysis showed that buffalo1, buffalo2 and buffalo3 had highest nucleotide identity (varied from 99.77% to 99.83%) with porcine-origin PCV2 strains. Moreover, in the phylogenetic tree, they were divided into three different clusters and belonged to the worldwide accepted genotypes of PCV2b, PCV2c and PCV2a, respectively. To summarize, this study first recorded complete genome information of PCV2 for non-porcine origins in China., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A total of 127 porcine samples were collected from 48 farms in six provinces in south China. The positive rate of porcine epidemic diarrhea virus (PEDV) was 43.0 % (55/127), and the co-infection rate of PEDV and transmissible gastroenteritis virus (TGEV) was 12.0 % (15/127). The partial S gene and complete M gene were amplified from PEDV-positive strains by RT-PCR, cloned, sequenced and compared with each other, as well as with the reference strains in GenBank. Sequence homology results of the partial S gene and complete M gene showed that all south China field PEDV strains had nucleotide (deduced amino acid) sequence identities of 86.7-98.7 % (83.2-99.3 %) and 96.1-100 % (95.0-100%), respectively, with the foreign reference strains reported in GenBank. Phylogenetic analysis of the partial S gene showed that all the south China PEDV strains and two Thailand strains (08UB01 and 08RB07) belong to the same group and differ genetically from European strains and early domestic strains. Phylogenetic analysis of the complete M gene showed that all south China PEDV strains have a close relationship with most of the strains in Korea and Thailand, but differ genetically from the vaccine strain (CV777).

In an attempt to assess whether silica induces lung cancer, a nested case-control study of 316 male lung cancer cases and 1352 controls was carried out among pottery workers and tungsten, copper-iron, and tin miners from five provinces in south central China. Exposure to dust and silica for each study subject was evaluated quantitatively by cumulative exposure measures based on historical industrial hygiene records. Measurements on confounders such as inorganic arsenic, polycyclic aromatic hydrocarbons (PAHs), and radon were also collected from the worksites. Information on cigarette smoking was obtained by interviews of the subjects or their next of kin. A significant trend of increasing risk of lung cancer with exposure to silica was found for tin miners, but not for miners working in tungsten or copper-iron mines. Concomitant and highly correlated exposures to arsenic and PAHs among tin miners were also found. Risk of lung cancer among pottery workers was related to exposure to silica, although the dose-response gradient was not significant. Risks of lung cancer were significantly increased among silicotic subjects in iron-copper and tin mines, but not in pottery factories or tungsten mines. The results of this study provide only limited support for an aetiological association between silica and lung cancer.

A cohort study of approximately 68,000 persons employed during 1972 to 1974 at metal mines and pottery factories in south central China was conducted to evaluate mortality from cancer and other diseases among workers exposed to different levels of silica and other dusts. A follow-up of subjects through December 31, 1989 revealed 6,192 deaths, a number close to that expected based on Chinese national mortality rates. There was, however, a nearly 6-fold increase in deaths from pulmonary heart disease (standard mortality ratio, 581; 95% confidence interval 538 to 626), and a 48% excess of mortality from nonmalignant respiratory diseases (standard mortality ratio, 148; 95% confidence interval, 139 to 158), primarily because of a more than 30-fold excess of pneumoconiosis. Pulmonary heart disease and noncancerous respiratory disease rates rose in proportion to dust exposure. Cancer mortality overall was not increased among the miners or pottery workers. There was no increased risk of lung cancer, except among tin miners, and trends in risk of this cancer with increasing level of dust exposure were not significant. Risks of lung cancer were 22% higher among workers with than without silicosis. The findings indicate that respiratory disease continues to be an occupational hazard among Chinese miners and pottery workers, but that cancer risks are not as yet strongly associated with work in these dusty trades.