The outbreak of COVID-19 poses unprecedent challenges to global health 1 . The new coronavirus, SARS-CoV-2, shares high sequence identity to SARS-CoV and a bat coronavirus RaTG13 2 . While bats may be the reservoir host for various coronaviruses 3,4 , whether SARS-CoV-2 has other hosts remains ambiguous. In this study, one coronavirus isolated from a Malayan pangolin showed 100%, 98.6%, 97.8% and 90.7% amino acid identity with SARS-CoV-2 in the E, M, N and S genes, respectively. In particular, the receptor-binding domain within the S protein of the Pangolin-CoV is virtually identical to that of SARS-CoV-2, with one noncritical amino acid difference. Results of comparative genomic analysis suggest that SARS-CoV-2 might have originated from the recombination of a Pangolin-CoV-like virus with a Bat-CoV-RaTG13-like virus. The Pangolin-CoV was detected in 17 of 25 Malayan pangolins analyzed. 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 that is highly related to SARS-CoV-2 in pangolins suggests that they have the potential to act as the intermediate host of SARS-CoV-2. The newly identified coronavirus in the most-trafficked mammal could represent a future threat to public health if wildlife trade is not effectively controlled.As coronaviruses (CoVs) are common in mammals and birds 5 , we used the whole genome sequence of SARS-CoV-2 (WHCV; GenBank accession No. MN908947) in a Blast search of SARS-relate CoV (SARSr-CoV) sequences in available mammalian and avian viromic, metagenomic, and transcriptomic data. This led to the identification of 34 highly related contigs in a set of pangolin viral metagenomes (Extended

The outbreak of 2019-nCoV in the central Chinese city of Wuhan at the end of 2019 poses unprecedent public health challenges to both China and the rest world 1 . The new coronavirus shares high sequence identity to SARS-CoV and a newly identified bat coronavirus 2 . While bats may be the reservoir host for various coronaviruses, whether 2019-nCoV has other hosts is still ambiguous. In this study, one coronavirus isolated from Malayan pangolins showed 100%, 98.2%, 96.7% and 90.4% amino acid identity with 2019-nCoV in the E, M, N and S genes, respectively. In particular, the receptor-binding domain of the S protein of the Pangolin-CoV is virtually identical to that of 2019-nCoV, with one amino acid difference. Comparison of available genomes suggests 2019-nCoV might have originated from the recombination of a Pangolin-CoV-like virus with a Bat-CoV-RaTG13-like virus. Infected pangolins showed clinical signs and histopathological changes, and the circulating antibodies reacted with the S protein of 2019-nCoV.

Toxoplasmosis is a disease caused by the protozoan Toxoplasma gondii which infects most genera of warm-blooded animals, including humans. The objective of this investigation is to evaluate the seroprevalence of toxoplasmosis in pigs in Chongqing Municipality, southwest China. Slaughterhouse pigs' serum samples collected from six different regions in Chongqing were assayed for T. gondii antibodies by an indirect hemagglutination test. The average seroprevalence of T. gondii were found in 30.6% (278/908) in slaughter pigs, ranging from 21.6% to 40.9% among different sampling sites. The results indicated that toxoplasmosis in swine of Chongqing Municipality was relatively serious, and the pork may be an important source for human infection with T. gondii. Comprehensive measures are needed to strengthen further prevention and control of the disease in Chongqing.

On mainland China, liver flukes of Fasciola spp. (Digenea: Fasciolidae) can cause serious acute and chronic morbidity in numerous species of mammals such as sheep, goats, cattle, and humans. The objective of the present study was to examine the taxonomic identity of Fasciola species in Yunnan province by sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2) of nuclear ribosomal DNA (rDNA). The ITS rDNA was amplified from 10 samples representing Fasciola species in cattle from 2 geographical locations in Yunnan Province, by polymerase chain reaction (PCR), and the products were sequenced directly. The lengths of the ITS-1 and ITS-2 sequences were 422 and 361-362 base pairs, respectively, for all samples sequenced. Using ITS sequences, 2 Fasciola species were revealed, namely Fasciola hepatica and Fasciola gigantica. This is the first demonstration of F. gigantica in cattle in Yunnan Province, China using a molecular approach; our findings have implications for studying the population genetic characterization of the Chinese Fasciola species and for the prevention and control of Fasciola spp. in this province.

Background Cryptosporidium spp., Giardia duodenalis and Enterocytozoon bieneusi are important zoonotic protists in humans and animals around the world, including nonhuman primates (NHPs). However, the prevalence, genetic identity and zoonotic potential of these pathogens in wild NHPs remain largely unclear. Methods A total of 348 fecal samples were collected from wild NHPs at four locations in Yunnan, southwestern China, and analyzed for these pathogens using nested PCR targeting various genetic loci and DNA sequence analysis of the PCR products. The zoonotic potential of the pathogens was assessed by comparing the genetic identity of the pathogens in these animals with that previously reported in humans. Results Altogether, two (0.6%), 25 (7.2%) and 30 (8.6%) samples were positive for Cryptosporidium sp., G. duodenalis and E. bieneusi, respectively. The Cryptosporidium sp. identified belonged to C. parvum subtype IIdA20G1. Both assemblages A (n = 3) and B (n = 22) were identified among G. duodenalis-positive animals. Five genotypes in zoonotic Group 1 were identified within E. bieneusi, including Type IV (n = 13), D (n = 7), Peru8 (n = 6), MMR86 (n = 2) and HNFS01 (n = 2). All genotypes and subtypes identified are known human pathogens or phylogenetically related to them. Conclusions Data from this study suggest a common occurrence of zoonotic genotypes of G. duodenalis and E. bieneusi in wild NHPs in southwestern China. Graphical Abstract

Cryptosporidium spp. are important foodborne and waterborne pathogens in humans and animals, causing diarrheal diseases. Cattle are one of the reservoirs of Cryptosporidium infection in humans. However, data on the occurrence of Cryptosporidium spp. in cattle in Yunnan Province remains limited. A total of 700 fecal samples were collected from Holstein cows (n = 442) and dairy buffaloes (n = 258) in six counties of Yunnan Province. The occurrence and genotypes of Cryptosporidium spp. were analyzed using nested PCR and DNA sequencing. Furthermore, the C. andersoni isolates were further analyzed using multilocus sequence typing (MLST) at four gene loci (MS1, MS2, MS3, and MS16), and the C. parvum isolate was subtyped by 60-kDa glycoprotein (gp60) loci. The occurrence of Cryptosporidium spp. in Holstein cows and dairy buffaloes was 14.7% (65/442) and 1.1% (3/258), respectively. Of these positive samples, 56 Holstein cow samples represented C. andersoni, four Holstein cow samples represented C. bovis, three Holstein cow samples represented C. ryanae, and one represented C. parvum. Meanwhile, only three dairy buffalo samples represented C. ryanae. MLST analysis of subtypes of C. andersoni detected four subtypes, including A5A4A2A1 (n = 7), A4A4A4A1 (n = 7), A1A4A4A1 (n = 2), and A4A4A2A1 (n = 1). One C. parvum isolate was identified as the IIdA18G1 subtype. These results revealed the high occurrence and high genetic diversity of Cryptosporidium spp. in Holstein cows in Yunnan Province, enriching the knowledge of the population genetic structure of Cryptosporidium spp. in Yunnan Province.

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Cyclospora spp. is a food-borne intestinal protozoan, which is widely distributed in the world and poses the risk of zoonosis. In order to reveal the prevalence of Cyclospora spp. in Holstein cattle in partial areas of the Yunnan Province, 524 fresh fecal samples of Holstein cattle were collected from Dali, Kunming, Chuxiong, and Qujing in Yunnan Province. A nested PCR amplification of the small subunit (SSU) rRNA gene of Cyclospora spp. was carried out, and the products of the nested PCR were further analyzed by restriction fragment length polymorphism (RFLP) using Bsp E Ⅰ. The results of the present study showed that 13 samples were positive for Cyclospora spp., and the total infection rate of Cyclospora sp. was 2.48%. The infection of Cyclospora spp. was detected in Dali, Qujing, and Chuxiong. Chuxiong showed the highest infection rate (5.71%), and infection rate in Dali and Qujing was 2.19% and 3.16%, respectively. Interestingly, the infection of Cyclospora spp. was not detected in Kunming. The infection of Cyclospora spp. showed no significant differences among different regions (p > 0.05). Cyclospora sp. infection was detected in all ages and sexes, but the differences were not significant (p > 0.05). Sequencing and phylogenetic analysis showed that five Cyclospora spp. samples were closely related to the Cyclospora spp. of humans, and the others were closely related to the Cyclospora spp. of bovines. The results of the present study suggested that there was an infection of Cyclospora spp. in Holstein cattle in the Yunnan Province, and the Cyclospora spp. showed a risk of zoonosis. Thus, the prevention and control of Cyclospora spp. should be strengthened in the Yunnan Province, China. The results of this investigation provide data references for the further research of Cyclosporiasis in Holstein cattle in the Yunnan Province.