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Crimean-Congo haemorrhagic fever (CCHF) is a re-emerging viral haemorrhagic fever causing outbreaks in Iran in the last 15 years. In this systematic review and meta-analysis, the status of Crimean-Congo haemorrhagic fever virus (CCHFV) in ticks would be evaluated. PubMed, Google Scholar and Web of Science were searched for peer-reviewed original papers published between 2000 and 1 July 2022. We included papers that evaluated the prevalence of CCHFV in individual ticks using reverse transcription polymerase chain reaction (RT-PCR). The pooled prevalence of CCHFV was 6.0% (95% confidence interval [CI]: 4.5–7.9%), with heterogeneity (I2 = 82.706; P < 0.0001). The prevalence of CCHFV was higher related to regions with above sea level of 1001–1500m (6.4%; 95% CI: 4.3–9.5%), an average temperature of ≤15 °C (8.3%; 95% CI: 5.6–12.0%), latitude of ≥36° (8.1%; 95% CI: 5.2–12.3%), an annual rainfall of 101–300 mm (9.8%; 95% CI: 6.1–15.4%) and humidity of ≥61% (10.2%; 95% CI: 5.1–19.3%). Due to the importance of CCHF, it is better to do new epidemiologic studies on ticks by related organizations and adjacent regions of some provinces in which human cases have been previously reported. • The remarkable burden of CCHFV infection in ticks in Iran compare to its neighbors. • Evaluation of the pooled prevalence of CCHFV in individual ticks. • Assessment of the pooled prevalence of CCHFV in different geographical regions of Iran. [ABSTRACT FROM AUTHOR]

Transmissible gastroenteritis virus (TGEV), which belongs to the coronaviruses (CoVs), causes diarrhea and high mortality rates in piglets and poses a huge threat and loss to the pig industry in China. We estimated the prevalence of TGEV in Chinese pig animals from 1983 to 2022 by screening 36 papers on TGEV investigations in China from databases such as China Knowledge Network (CNKI), Wanfang Database, Science and Technology Journal Repository (VIP), PubMed, and ScienceDirect, excluding duplicate literature and other host studies according to the exclusion criteria we developed, and excluding literature with incomplete data to extract information from studies that could estimate the prevalence of TGEV infection in pigs in mainland China. A total of 36 studies (including data from 50,403 pigs) met our evaluation criteria. The overall estimated prevalence of TGEV infection in pigs in China is 10% (3887/50403), and the prevalence of TGEV in northeast China is 38% (2582/3078700) is significantly higher than the rest of China. The prevalence of TGEV infection was related to the sampling season and region. The results of the study show that the prevalence of TGEV is clearly seasonal and regional. Therefore, further research and monitoring of the prevalence of TGEV infection and the development of control programs based on different conditions are essential. In addition, effective and robust regulatory measures should be taken in colder regions to prevent the spread and transmission of TGEV in pigs. • This is the first meta-analysis of the nationwide prevalence of Transmissible Gastroenteritis (TGEV) among swine in China. • The prevalence of TGEV was 10% in China. • Season and region were a risk factor associated with the prevalence rate of TGEV. • Through meta-analysis can provide adequate measures to control TGEV, reduce economic losses, and prevent the spread and transmission of TGEV in Chinese pig herds. [ABSTRACT FROM AUTHOR]

The possible role of Blastocystis sp. and Giardia lamblia infections in the development of irritable bowel syndrome (IBS) has long been controversial. In this study, we conducted a systematic review and meta-analysis to investigate whether these protozoan infections are associated with IBS development. We systematically searched international databases for all studies that reported these protozoa in IBS patients published by May 10, 2021. Studies were included in the review if they were observational studies with confirmed patients with IBS (in case-control and cross-sectional studies) or parasitic infections (cohort studies) with an appropriate control group. Pooled odds ratios (ORs) and 95% confidence intervals were estimated using a random-effects meta-analysis model for included studies. A total of 32 papers (42 datasets), including 29 papers (31 datasets) for Blastocystis sp./IBS and 11 papers (11 datasets) for G. lamblia /IBS met the eligibility criteria. Our results indicated that the individuals with Blastocystis sp. infection were significantly at a higher risk of IBS development (OR, 1.78; 95%CI, 1.29–2.44). Moreover, cohort studies indicated a significant positive association between G. lamblia infection and IBS risk (OR, 5.47; 95%CI, 4.23–7.08); while an increasing but no statistically significant risk was observed in case-control studies (OR, 1.19; 95%CI, 0.75–1.87). Our findings suggested that Blastocystis sp. and G. lamblia infections are associated with the increased risk of developing IBS. Despite these results, further studies are needed to determine the effect of these protozoa on IBS development. • We evaluate the role of Blastocystis sp. and Giardia lamblia infections in the development IBS. • Blastocystis sp. infection was significantly associated with IBS. • Giardiasis was significantly associated with IBS in cohort studies. [ABSTRACT FROM AUTHOR]

Abstract At present, there is not any available accepted vaccine for prevention of Toxoplasma gondii (T. gondii) in human and animals. We conducted literature search through English (Google Scholar, PubMed, Science Direct, Scopus, EBSCO, ISI Web of Science) scientific paper databases to find the best vaccine candidates against toxoplasmosis among T. gondii antigens. Articles with information on infective stage, pathogenicity, immunogenicity and characterization of antigens were selected. We considered that the ideal and significant vaccines should include different antigens and been expressed in all infective stages of the parasite with a high pathogenicity and immunogenicity. Evaluation within this systematic review indicates that MIC 3, 4, 13, ROP 2, RON 5, GRA 1, 6, 8, 14 are expressed in all three infective stages and have pathogenicity and immunogenicity. MIC 5, ROM 4, GRA 2, 4, 15, ROP 5, 16, 17, 38, RON 4, MIC 1, GRA 10, 12, 16, SAG 3 are expressed in only tachyzoites and bradyzoites stages of T. gondii with pathogenicity/immunogenicity. Some antigens appeared to be expressed in a single stage (tachyzoites) but have high pathogenicity and induce immune response. They include enolase2 (ENO2), SAG 1, SAG5D, HSP 70, ROM 1, ROM 5, AMA 1, ROP 18, RON2 and GRA 24. In conclusion, current vaccination against T. gondii infection is not satisfactory, and with the increasing number of high-risk individuals, the development of an effective and safe specific vaccine is greatly valuable for toxoplasmosis prevention. This systematic review reveals prepare candidates for immunization studies. [ABSTRACT FROM AUTHOR]

Theileria , one of the causative agents of blood protozoan, has brought a huge economic loss to the cattle industry worldwide. However, the epidemiology of Theileria in Chinese cattle has not been systematically investigated. This comprehensive review aimed at investigating the prevalence of Theileria infection in cattle in China. A total of 48 published papers on Theileria infection in cattle in China (including data from 21,366 animals) from inception to October 8, 2021 met the inclusion standard after searching in five databases (Technology Periodical Database, Wan Fang Database, China National Knowledge Infrastructure, PubMed, and ScienceDirect). The pooled prevalence of Theileria in cattle in China was 32.4% identified by using a random effects model. The prevalence in Northeastern China (45.3%) was higher than that in other regions. In the sex subgroup, the prevalence of Theileria was higher in females (48.9%) than that in males (45.8%). The prevalence of Theileria was higher in cattle of free range (34.4%) compared with that of intensive farming (22.3%). The prevalence prior to 2013 (36.1%) was higher than that after 2013 (33.6%). Among three cattle species, dairy cows had the lowest prevalence (21.5%). The prevalence of Theileria (T.) annulata (22.2%) and T. sergenti (26.2%) was higher than other species of Theileria (T. buffeli : 17.5%, T. luwenshuni : 0.9%, T. orientalis : 15.5%, T. ovis : 0.21%, T. sinensis : 20.2%, T. uilenbergi : 6.2%, Others: 0.9%). We also analyzed the impact of different geographic factor subgroups (longitude, latitude, precipitation, temperature, humidity, and altitude) on the prevalence of Theileria in cattle. Among them, climatic factors of longitude, latitude, precipitation, humidity, temperature were associated with the prevalence of Theileria. These analyses suggested that Theileria was common in cattle in China. Targeted prevention programs based on geographic and climatic conditions in different areas may play an important role in reducing Theileria infection among cattle. • This is the first meta-analysis of the prevalence of Theileria in cattle in China. • Theileriosis was common and unevenly varied in Chinese cattle, detection tests, species of Theileria had significant effects. • High temperature, heavy rainfall and humidity may be the key points for controlling the spread of Theileria. [ABSTRACT FROM AUTHOR]

The intestinal parasite Blastocystis sp. is a widely distributed protist among humans and various animal hosts, with significant prevalence in developing countries. Due to the zoonotic nature of its subtypes (STs), we aimed at global estimation of the prevalence, STs distribution, zoonotic potential, and associated risk factors of Blastocystis sp. infection in domestic pigs (Sus domesticus) and wild pigs/wild boars (Sus scrofa). The study was designed and conducted in 2021 via searching articles in PubMed, Scopus, Google Scholar, and Web of Science databases, based on the PRISMA checklist, and meta-analysis was done using a random-effects model to calculate the weighted estimates and 95% confidence intervals (95% CIs). Totally, 43 papers (47 datasets) reported data on 7977 examined pigs in 24 countries with a total prevalence of 50.9% (95% CI: 42.8–59%). In details, prevalence was higher among domestic pigs [52.4% (95% CI: 43.9–60.7%)] than wild boars [31.2% (95% CI: 11.2–62%)], but is poorly statistically supported as far as the CIs largely overlap. Out of 28 reported STs, nine (ST1-ST7, ST10, and ST15) were reported from domestic pigs, while six (ST1, ST3-ST5, ST8, and ST15) had been isolated from wild boars. Among nine zoonotic STs (ST1-ST8, and ST12), all were identified in examined swine populations, except for ST12. As well, ST1 and ST5 were probably the most frequently circulating STs among these animals. In addition, male and older pigs showed higher Blastocystis sp. infection. Altogether, Blastocystis epidemiology and the distribution of its related STs in pigs is still open to question and requires more extensive studies, especially in the neglected regions of the world. • The total prevalence of Blastocystis sp. infection in swine populations was 50.9% (95% CI: 42.8–59%). • The pooled frequency was higher among domestic pigs [52.4% (95% CI: 43.9–60.7%)] than wild boars [31.2% (95% CI: 11.2–62%)], but is poorly statistically supported as far as the CIs largely overlap. • Nine STs (ST1-ST7, ST10, and ST15) were reported from domestic pigs, while six STs (ST1, ST3-ST5, ST8, and ST15) had been isolated from wild boars. • Among nine zoonotic STs (ST1-ST8, and ST12), all were identified in examined swine populations, except for ST12. • Male and older pigs showed higher Blastocystis sp. infection. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is a zoonotic pathogen that has spread worldwide. The HEV reservoir associated with livestock hepatitis E poses a huge threat to public health. Awareness of the prevalence and spatial distribution of livestock hepatitis E is valuable to prevent and control diseases caused by HEV, especially human hepatitis E infection. Currently, swine, including pigs (Sus scrofa), are recognized as the major reservoir of HEV. Therefore, we conducted a systematic review and meta-analysis to evaluate the pooled prevalence of HEV among swine in China. A total of 71 published papers on HEV infection in swine in China (including data from 49,523 animals) from January 1, 2010 to December 31, 2019 met the standard after searching five databases including the Technology Periodical Database, the Wan Fang Database, the China National Knowledge Infrastructure, PubMed, and ScienceDirect. A random effects model was used to calculate the pooled prevalence of HEV in swine. The results showed that the seroprevalence was 48.0% (95% confidence interval (CI) 39.6–56.9) and the prevalence of HEV RNA was 14.4% (95% CI 10.7–18.5). The estimated overall prevalence was 34.1% (95% CI 27.2–41.4). Central China (68.0%, 95% CI 42.2–89.1) had a significantly higher prevalence than other regions. In the publication year subgroup, the prevalence in 2016 or later (27.2%, 95% CI 19.3–36.0) was significantly lower than that in 2011 or earlier (49.0%, 95% CI 36.2–61.8). The prevalence of IgG (42.9%, 95% CI 31.7–54.6) was significantly higher than that of IgM (4.9%, 95% CI 1.6–9.7). Suckling piglets (15.6%, 95% CI 6.6–27.1) had a lower prevalence compared with that in other age groups. In all sample types, body fluids showed the highest prevalence (50.5%, 95% CI 41.7–59.3). Moreover, the pooled prevalence of HEV in boars was higher than that in sows (35.4% > 17.3%). The analysis suggested that HEV infection is common among swine in China. Further strengthening HEV testing in boars, controlling environmental pollution, and reducing the mixed feeding of different stages could contribute to reducing HEV infection in pigs in China and the risk of porcine HEV infection in humans. • Hepatitis E virus (HEV) is prevalent among swine. • HEV distributed unevenly in different regions. • The prevalence of HEV varied in swine of different ages and sexes. • More accurate results may be obtained by comprehensive detections. [ABSTRACT FROM AUTHOR]

Bovine viral diarrhea is an infectious disease that causes symptoms such as bovine diarrhea and abortion. It can cause severe losses to the animal husbandry, and the overall epidemic situation of yak's BVDV in China is unclear. Meta-analysis can reveal the basic epidemic situation of BVDV in different yak distribution areas in China, and estimate potentially related factors, to pave the way for clarifying the epidemic situation of yak in the domestic scope. We proceeded to a systematic review and meta-analysis of data from papers on the BVDV incidence and prevalence in yaks in China by searching PubMed, ScienceDirect, Chinese Web of Knowledge (CNKI), Wanfang, and Chongqing VIP for publication from 1987 to 2019. We excluded reviews and duplicate studies, 24 studies denouncing the prevalence of BVDV in yak in China were selected upon our inclusion criterion finally. We estimated the pooled prevalence of BVDV infection in yaks by a random-effects model and evaluated its overall infection burden in China. In total, the pooled prevalence of BVDV in yaks in China was 36.0% (95% CI 25.6%–46.4%) based on the data obtained from 13,446 yaks, by detecting antigens and antibodies. The highest BVDV positive rate in yak reached 67.5% in Xinjiang province of China. The prevalence in the six provinces of China was validated to be quite variable (24.4%–67.5%) and reached 369% in yaks of northwest China. Besides, the BVDV antigen-positive rate was estimated at 13.8% (95% CI 8.6%–19.0%) based on 5 studies, comparatively, the pooled BVDV antibody-based on 18 studies was about 32.9% (95% CI 24.6%–41.2%) in China. This systematic review and meta-analysis firstly established an estimated prevalence of BVDV in yaks in China, as a whole, and estimates potential relevant factors, including geographic location, publication year, age, detection methods, etc., Our findings suggest that the scientific community or decision-makers can formulate corresponding prevention and control plans based on potential risk factors. • Systematic review and meta-analysis of BVDV infection in yaks of China for the first time. • We estimate potentially relevant factors, including geographic location, publication year, age, detection methods, etc. • ELISA method is more suitable for large-scale BVDV epidemiological investigation in yaks of China than other methods. [ABSTRACT FROM AUTHOR]

Avian influenza viruses (AIVs) in wild birds pose a pandemic threat to humans and to the poultry industry. To assess AIV and AIV antibody prevalence in wild birds in China, a systematic review and meta-analysis were conducted. We searched PubMed, Google Scholar, Cochrane Library, Clinical Trial, VIP, CNKI, and WANFANG for published papers related to the prevalence of AIVs and their associated antibodies in wild birds in China from Mar. 10, 2005 to Sept. 20, 2018. Repeat studies, reviews, and other host studies were excluded, as well as those with inconsistent data, incomplete information, or only prevalence data or data from outside of mainland China. In total, data from 28 publications were compiled and analyzed. Based on out meta-analysis, the pooled prevalence of AIVs in wild birds in China was found to be 2.5% (571/23,024), and the pooled prevalence of AIV antibodies was 26.5% (1,210/4,566). The pooled prevalence of AIVs was significantly higher in wild birds from Central China (5.5%, 271/4, 955) compared to all other regions and the pooled prevalence of AIV antibodies was significantly in wild birds from South China (56.8%, 92/162) in comparison to all other regions. The prevalence of both AIVs and AIV antibodies in Anseriformes were higher compared to non-Anseriformes. In addition, the largest number of studies found in this review were on the HA subtypes of AIVs (H5, H7, and H9) and their associated antibodies. In summary, our findings suggest that the prevalence of AIVs and their antibodies in wild birds vary among regions and species of wild bird. Thus, further monitoring of the prevalence of AIVs and their antibodies in wild birds in China is necessary and should be used for guiding powerful and effective regulatory measures that will prevent the spread of AIVs across species. • This is the first systematic review and meta-analysis of the prevalence of AIVs and its antibodies among wild birds in mainland China. • The data of 28 articles met the selection criteria, and the prevalence of AIVs was 2.5%, and the prevalence of AIVs antibodies was 26.5%. • The prevalence of AIVs and its antibodies among wild birds in different regions, species of wild birds, varied considerably. • Continuous monitoring AIVs and its antibodies among wild birds in China is necessary. [ABSTRACT FROM AUTHOR]