Risk Factors For Human Infection Research Articles

Assessing concordance between Campylobacter prevalence in broilers and human cases before and during the COVID-19 pandemic in Lower Saxony, Germany, considering fresh chicken meat consumption patterns.

As the most common foodborne disease, number of campylobacteriosis decreased in Germany with the beginning of the COVID-19 pandemic in 2020. As the consumption of fresh chicken meat is a major risk factor for human infection, this study investigated the relationship between Campylobacter contamination levels on chicken carcasses and human cases in Lower Saxony, Germany and observed fresh chicken meat consumption patterns between 2018 and 2021 including the time of the COVID-19 pandemic. Campylobacter levels in broilers and human cases were classified based on the median and descriptively analysed per week using contingency tables. Before the COVID-19 pandemic (2018 and 2019), high Campylobacter contamination levels on neck samples and many human cases were more present, whereas with the beginning of the COVID-19 pandemic (2020 and 2021), low contamination levels on chicken carcasses and few human cases were more present. Lowest concordance between both parameters was shown in 2018 (Cohen's cappa coefficient: 0.37) and 2020 (0.38). The highest concordance was examined in 2021 (0.69). The private consumption of fresh chicken meat in Lower Saxony increased significantly with the beginning of the COVID-19 pandemic in 2020 by 63.9 tonnes compared to 2019 to an average of 453.5 tonnes per week. Public health measures and a reduced number of medical treatments have undoubtedly had an impact on less reported human cases during the COVID-19 pandemic. However, number of human cases remained at a low level in Germany in 2023 while chicken meat consumption increased. Thus, further risk assessments regarding the risk of campyloabcteriosis due to chicken meat consumption should include the country of origin, as the level of contamination of chicken carcasses varies between European countries.

Risk Factors Associated with Human Brucellosis: A Systematic Review and Meta-Analysis.

Background: Brucellosis is a zoonosis disease that can affect humans and a wide range of domestic and wild animals. Susceptibility to brucellosis in humans can be related to various factors, such as nutritional and occupational factors. This study evaluated factors related to brucellosis and identified influential risk factors for human infection. Methods: We performed a systematic literature review and meta-analysis of studies in PubMed, Web of Science, and Scopus. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to measure the strength of the association between some potential factors and the risk of brucellosis. Results: From 277 initial studies, 19 case-control studies were included in this review. Significant risk factors for brucellosis included occupation (OR 3.31, 95% CI 1.68-6.55), having aborted animals (OR 4.16, 95% CI 2.03-8.50), consumption of meat (OR 2.17, 95% CI 1.44-3.36), unpasteurized milk (OR 3.86, 95% CI 1.81-8.23), and raw cheese (OR 4.20, 95% CI 1.63-10.85). Conclusion: The results of this study advance the understanding of the etiology of brucellosis. In this meta-analysis, we found the association of different environmental factors with the risk of brucellosis. Additional high-quality prospective studies are needed to determine whether these factors cause brucellosis and to identify other factors.

Serosurvey for H5, H7 and H9 avian influenza viruses in local chickens in live bird markets within Kaduna metropolis, Nigeria

Since the first 2006 Avian Influenza (AI) outbreak in Nigeria, it has continued to circulate and ravage the poultry industry with huge economic losses above 130 billion naira. Local poultry are important sources of AI transmission and maintenance of the highly pathogenic avian influenza H5N1. Live bird markets (LBMs) are “breeding grounds” and major risk factors for human infection of AI. The seroprevalence of AI in local chickens in LBMs in Kaduna Metropolis, Nigeria was determined. Sera were obtained from the local chickens (n=300) in 5 daily LBMs and subjected to competitive enzyme-linked immunosorbent assay (c-ELISA) to detect the nucleoprotein antibodies. The c-ELISA positive samples were further screened by haemagglutination inhibition (HI) test for AI using H5, H7 and H9 antigens. The overall AI seroprevalence was 1.7 % with the highest individual seroprevalence of 3.3% in Kawo and Railway LBMs. There was no statistically significant association between the location of LBMs and AI presence, and between the sex and presence of AI antibodies (p = 0.427). One sample was HI positive for antibodies against H5, H7 and H9 with mean titers of 4, 2.5 and 3.5 log2, respectively. This implies the potential danger of the spread of AI among humans and animals. There should be sustained surveillance and biosecurity in the live bird market.

A Novel Quadruple Gene-Deleted BoHV-1-Vectored RVFV Subunit Vaccine Induces Humoral and Cell-Mediated Immune Response against Rift Valley Fever in Calves.

Rift Valley fever virus (RVFV) is considered to be a high biodefense priority based on its threat to livestock and its ability to cause human hemorrhagic fever. RVFV-infected livestock are also a significant risk factor for human infection by direct contact with contaminated blood, tissues, and aborted fetal materials. Therefore, livestock vaccination in the affected regions has the direct dual benefit and one-health approach of protecting the lives of millions of animals and eliminating the risk of severe and sometimes lethal human Rift Valley fever (RVF) disease. Recently, we have developed a bovine herpesvirus type 1 (BoHV-1) quadruple gene mutant virus (BoHV-1qmv) vector that lacks virulence and immunosuppressive properties due to the deletion of envelope proteins UL49.5, glycoprotein G (gG), gE cytoplasmic tail, and US9 coding sequences. In the current study, we engineered the BoHV-1qmv further by incorporating a chimeric gene sequence to express a proteolytically cleavable polyprotein: RVFV envelope proteins Gn ectodomain sequence fused with bovine granulocyte-macrophage colony-stimulating factor (GMCSF) and Gc, resulting in a live BoHV-1qmv-vectored subunit vaccine against RVFV for livestock. In vitro, the resulting recombinant virus, BoHV-1qmv Sub-RVFV, was replicated in cell culture with high titers. The chimeric Gn-GMCSF and Gc proteins expressed by the vaccine virus formed the Gn-Gc complex. In calves, the BoHV-1qmv Sub-RVFV vaccination was safe and induced moderate levels of the RVFV vaccine strain, MP12-specific neutralizing antibody titers. Additionally, the peripheral blood mononuclear cells from the vaccinated calves had six-fold increased levels of interferon-gamma transcription compared with that of the BoHV-1qmv (vector)-vaccinated calves when stimulated with heat-inactivated MP12 antigen in vitro. Based on these findings, we believe that a single dose of BoHV-1qmv Sub-RVFV vaccine generated a protective RVFV-MP12-specific humoral and cellular immune response. Therefore, the BoHV-1qmv sub-RVFV can potentially be a protective subunit vaccine for cattle against RVFV.

Salmonella in reptiles: a review of occurrence, interactions, shedding and risk factors for human infections.

Salmonella are considered a part of the normal reptile gut microbiota, but have also been associated with disease in reptiles. Reptile-associated salmonellosis (RAS) can pose a serious health threat to humans, especially children, and an estimated 6% of human sporadic salmonellosis cases have been attributed to direct or indirect contact with reptiles, although the exact number is not known. Two literature searches were conducted for this review. The first evaluated reports of the prevalence of Salmonella in the intestinal tracts of healthy reptiles. Salmonella were most commonly detected in snakes (56.0% overall), followed by lizards (36.9%) and tortoises (34.2%), with lower detection rates reported for turtles (18.6%) and crocodilians (9%). Reptiles in captivity were significantly more likely to shed Salmonella than those sampled in the wild. The majority of Salmonella strains described in reptiles belonged to subspecies I (70.3%), followed by subspecies IIIb (29.7%) and subspecies II (19.6%). The second literature search focused on reports of RAS, revealing that the highest number of cases was associated with contact with turtles (35.3%), followed by lizards (27.1%) and snakes (20.0%). Reptiles associated with RAS therefore did not directly reflect prevalence of Salmonella reported in healthy representatives of a given reptile group. Clinical symptoms associated with RAS predominantly involved the gastrointestinal tract, but also included fever, central nervous symptoms, problems with circulation, respiratory symptoms and others. Disease caused by Salmonella in reptiles appears to be dependent on additional factors, including stress, inadequate husbandry and hygiene, and other infectious agents. While it has been suggested that reptile serovars may cause more severe disease than human-derived strains, and some data is available on invasiveness of individual strains in cell culture, limited information is available on potential mechanisms influencing invasiveness and immune evasion in reptiles and in RAS. Strategies to mitigate the spread of Salmonella through reptiles and to reduce RAS focus mostly on education and hygiene, and have often been met with some success, but additional efforts are needed. Many aspects regarding Salmonella in reptiles remain poorly understood, including the mechanisms by which Salmonella persist in reptile hosts without causing disease.

Reemergence of Marburgvirus disease: Update on current control and prevention measures and review of the literature.

In 1967, the very first case of the Marburgvirus disease (MVD) was detected in Germany and Serbia sequentially. Since then, MVD has been considered one of the most serious and deadly infectious diseases in the world with a case-fatality rate between 23% and 90% and a substantial number of recorded deaths. Marburgvirus belongs to the family of Filoviridae (filoviruses), which causes severe viral hemorrhagic fever (VHF). Some major risk factors for human infections are close contact with African fruit bats, MVD-infected non-human primates, and MVD-infected individuals. Currently, there is no vaccine or specific treatment for MVD, which emphasizes the seriousness of this disease. In July 2022, the World Health Organization reported outbreaks of MVD in Ghana after two suspected VHF cases were detected. This was followed in February and March 2023 with the emergence of the virus in two countries new to the virus: Equatorial Guinea and Tanzania, respectively. In this review, we aim to highlight the characteristics, etiology, epidemiology, and clinical symptoms of MVD, along with the current prevention measures and the possible treatments to control this virus.

Current control options and a way towards risk-based control of Toxoplasma gondii in the meat chain

Toxoplasma gondii is a zoonotic protozoan with a wide range of hosts and cosmopolitan distribution. Due to its impact on human and animal health, as well as related economic losses, T. gondii is considered as one of the most significant foodborne pathogens nowadays. Consumption of raw or undercooked meat is a well known risk factor for human infection. However, there is no legislation regarding control of T. gondii in the meat chain, and current meat safety assurance systems (MSAS) have little control over this parasite. Traditional meat inspection is not capable of detecting microscopic cysts of T. gondii in the tissues of slaughter animals, and available laboratory tests are still not sufficiently sensitive or specific to detect infection in individual carcasses. Possible solutions for overcoming these challenges and gaining a higher level of control over T. gondii in the meat chain come in the form of a risk-based meat safety assurance system (RB-MSAS) that incorporates risk-categorisation of farms and targeted interventions, as well as education of all interested parties.

Presence of Coxiella burnetii in dairy cattle and farms in the Czech Republic.

The aims of this study were to evaluate the prevalence of Coxiella burnetii on both herd and animal level based on ELISA and PCR tests. Antibodies to C. burnetii were detected in 22 out of the 24 bulk tank milk samples (91.6%) tested by ELISA and the IS1111 element of C. burnetii was detected in 10 out of the 24 samples (41.6%) by real-time polymerase chain reaction (PCR). ELISA testing showed individual seropositivity in 67 out of the 165 cows (40.6%) examined in 24 dairy cattle farms in different parts of the Czech Republic. Our study revealed that the prevalence of C. burnetii has increased substantially in the Czech Republic over the past 30 years, and that the causative agent is a potential risk factor for some reproductive problems in dairy farms and a possible risk factor for human infection.

Seroprevalence, Direct Detection and Risk Factors for Toxoplasma gondii Infection in Pigs in Serbia, and Influence of Biosecurity Measures.

Consumption of Toxoplasma gondii contaminated pork is a major risk factor for human infection. We thus conducted a cross-sectional survey on the seroprevalence of T. gondii infection in a representative sample of slaughter pigs from throughout Serbia and examined the influence of farm biosecurity-related risk factors on infection. In addition, direct detection of the parasite (by mouse bioassay) or its DNA was performed in the hearts of a subset of seropositive sows. The overall seroprevalence in the sample of 825 pigs as determined by the modified agglutination test (MAT) was 16.5%. Older age and inadequate rodent control were independent infection risk factors for pigs. In a subset of 581 pigs with complete biosecurity-related data, in addition to older age, smallholders’ finishing type farms (as opposed to farrow-to-finish), multispecies farming, and origin from Western and Central and South-Eastern Serbia (vs. the Northern region), all increased the risk of infection, while the absence of disinfection boot-dips in front of each barn and Belgrade district origin (vs. the Northern region) were associated with a 62% and 75% lower risk of infection, respectively. Evidence of viable parasites was obtained in 13 (41.9%) of the 31 bioassayed sow hearts, of which by isolation of brain cysts in seven, by detection of T. gondii DNA in an additional four, and by serology in another two. Recovery of brain cysts mostly (5/7) from sows with a MAT titre of ≥1:100 indicates the risk for consumers. These results highlight the public health risk from pork consumption and point to mandatory use of professional rodent control services, abstaining from multispecies farming, keeping disinfection boot-dips clean and freshly refilled, as well as strict implementation of zoo-hygienic measures on smallholders’ farms as specific farm biosecurity measures needed for its reduction.

Prevalence of Toxoplasmic Retinochoroiditis in an Australian Adult Population: A Community-Based Study

Toxoplasmic retinochoroiditis is the most common clinical manifestation of an infection with the protozoan parasite, Toxoplasma gondii. Up to 50% of the human population is estimated to be infected with T.gondii; however, the epidemiology of toxoplasmic retinochoroiditis has not been widely reported. We sought to estimate the prevalence of toxoplasmic retinochoroiditis in Australia using data that were collected as part of the Busselton Healthy Ageing Study. Cross-sectional, community-based, prospective cohort study. 5020 Australian adults (2264 men and 2756 women; age range, 45-69 years, and median age, 58 years). Retinal color photographs, centered on the optic disc and macula, were captured using a digital retinal camera after the dilation of the pupils. Three uveitis-subspecialized ophthalmologists assessed each pigmented retinal lesion, and complete concordance of opinion was required to assign a toxoplasmic etiology. Serum T.gondii immunoglobulin (Ig)G levels were measured for those participants with retinal lesions judged to be toxoplasmic retinochoroiditis. Prevalence of toxoplasmic retinochoroiditis. Eight participants (0.16%) had retinal lesions that were considered to have the characteristic appearance of toxoplasmic retinochoroiditis, plus detectable serum T.gondii IgG, consistent with the diagnosis of toxoplasmic retinochoroiditis. On the assumption that 23.81% of retinal lesions occur at the posterior pole, as reported in a community-based survey conducted in Brazil (Sci Rep. 2021;11:3420), the prevalence of toxoplasmic retinochoroiditis was estimated to be 0.67% or 1 per 149 persons. Toxoplasmic retinochoroiditis is common in Australian adults. Efforts to quantify and address risk factors for human infection with T.gondii are justified.

Whole-Genome Sequencing and Virulome Analysis of Escherichia coli Isolated from New Zealand Environments of Contrasting Observed Land Use.

ABSTRACTGeneric Escherichia coli is commonly used as an indicator of fecal contamination to assess water quality and human health risk. Where measured E. coli exceedances occur, the presence of other pathogenic microorganisms, such as Shiga toxin-producing E. coli (STEC), is assumed, but confirmatory data are lacking. Putative E. coli isolates (n = 709) were isolated from water, sediment, soil, periphyton, and feces samples (n = 189) from five sites representing native forest and agricultural environments. Ten E. coli isolates (1.41%) were stx2 positive, 19 (2.7%) were eae positive, and stx1-positive isolates were absent. At the sample level, stx2-positive E. coli (5 of 189, 2.6%) and eae-positive isolates (16 of 189, 8.5%) were rare. Using real-time PCR, these STEC-associated virulence factors were determined to be more prevalent in sample enrichments (stx1, 23.9%; stx2, 31.4%; eae, 53.7%) and positively correlated with generic E. coli isolate numbers (P < 0.05) determined using culture-based methods. Whole-genome sequencing (WGS) was undertaken on a subset of 238 isolates with assemblies representing seven E. coli phylogroups (A, B1, B2, C, D, E, and F), 22 Escherichia marmotae isolates, and 1 Escherichia ruysiae isolate. Virulence factors, including those from extraintestinal pathogenic E. coli, were extremely diverse in isolates from the different locations and were more common in phylogroup B2. Analysis of the virulome from WGS data permitted the identification of gene repertoires that may be involved in environmental fitness and broadly align with phylogroup. Although recovery of STEC isolates was low, our molecular data indicate that they are likely to be widely present in environmental samples containing diverse E. coli phylogroups.IMPORTANCE This study takes a systematic sampling approach to assess the public health risk of Escherichia coli recovered from freshwater sites within forest and farmland. The New Zealand landscape is dominated by livestock farming, and previous work has demonstrated that “recreational exposure to water” is a risk factor for human infection by Shiga toxin-producing Escherichia coli (STEC). Though STEC isolates were rarely isolated from water samples, STEC-associated virulence factors were identified more commonly from water sample culture enrichments and were associated with increased generic E. coli concentrations. Whole-genome sequencing data from both E. coli and newly described Escherichia spp. demonstrated the presence of virulence factors from E. coli pathotypes, including extraintestinal pathogenic E. coli. This has significance for understanding and interpreting the potential health risk from E. coli where water quality is poor and suggests a role of virulence factors in survival and persistence of E. coli and Escherichia spp.

Intestinal Parasite Infections among Food Vendors at Awkuzu, Nigeria

Intestinal parasites have been known to cause severe symptoms of malnourishment and abdominal pains as well as impairment of physical and mental development especially in children. Poor hygiene among food vendors is a major risk factor for human infections with protozoan cysts, helminth eggs and larvae. This cross-sectional study on intestinal parasites among food vendors in Awkuzu, Oyi Local Government Area of Anambra State was carried out between April and June, 2021. Two hundred consenting males (32%) and females (68%) were studied under age-groups of ≤ 20, 21-30, 31-40, 41-50, and &gt;50 years. Stool sample submitted by each participant was routinely examined in our mobile laboratory using Saline/iodine wet preparation and Formol-ether concentration techniques. Parasites were identified with standard keys. Data obtained were analyzed using the Chi-square test for homogeneity of infection among gender and age groups. Forty-eight (24.0%) of all stool samples were positive for intestinal parasite infections; with overall prevalence of 12.5, 6.0 and 5.5% for helminth, protozoa, and mixed helminth-protozoa infections, respectively. Overall frequency of infection with Ascaris lumbricoides was 42.7%, followed by Strongyloides stercoralis (24%) while Entamoeba histolytica, Taenia spp., Hookworm spp., and Giardia lamblia recorded 10.7, 9.3, 8.0 and 5.3% respectively. Overall gender prevalence revealed that a total of 27 (13.5 %) males were infected and 21 (10.5 %) females were infected, there was no significant difference (p&lt;0.05) between infections in males and in females. Overall age prevalence revealed that more than one-third 18 (9.0 %) of the infections occurred in the ≤ 20 age group, and the least prevalence 2 (1.0%) occurred in the &gt;50 age group. This study has demonstrated intestinal parasite infections among food vendors studied. Irregular deworming and poor hand hygiene among food vendors are potential risks for food-borne diseases transmission to unsuspecting food consumers. Health education and social behavioral change communication on the importance of regular deworming, improved hand hygiene and WASH practices, as well as provision of better waste management infrastructure should be put in place to prevent any outbreak of food-borne diseases in the area.

Prevalence of Coxiella burnetii in bovine placentas in Hungary and Slovakia: Detection of a novel sequence type - Short communication.

Cotyledons (n = 167) from 30 Hungarian and 5 Slovakian dairy cattle herds were analysed for Coxiella burnetii by real-time PCR targeting the IS1111 gene. Eighty (88.9%) out of the 90 cotyledons from retained placentas and 31 (40.3%) out of the 77 cotyledons from normally separated placentas tested positive. Seventeen out of the 80 positive samples (21.3%) originating from retained placentas were found to be highly loaded with C. burnetii with a cycle threshold (Ct) value lower than or equal to 27.08, ranging between 11.92 and 27.08. The rest of the positive samples from retained fetal membranes and from normally separated placentas were moderately loaded with C. burnetii DNA. Five out of the ten samples showing the strongest positivity (Ct 11.92-18.28) from retained placentas were genotyped by multispacer sequence typing based on ten loci, which revealed sequence type (ST) 61, a type that had not been detected in Hungary and Slovakia previously. Retained placenta was more likely in cows with C. burnetii PCR-positive cotyledons (odds ratio: 12.61, P = 0.0023). The high C. burnetii DNA load found in retained fetal membranes may be a potential risk factor for human infection and may also be associated with the retention of fetal membranes.

High Seroprevalence of Toxoplasma gondii in Slovenian Wild Boars (Sus scrofa).

Simple SummaryToxoplasma gondii is a parasite that can cause serious disease in humans, especially in pregnant women. This parasite is found in many animals and people can be infected by eating raw or undercooked meat. Wild boar are known to harbor this parasite; populations and habitats have increased in the past decade, as it also increased the consumption of venison. The European population of wild boar has a mean prevalence of 26%. In our study, we found that the prevalence in the Slovenian wild boar population is 62%, the highest in the world to date. The prevalence was influenced by age and weight, but not by gender. In conclusion, the hunting community should be made aware of the high risk of parasite exposure when dealing with wild boar meat.Toxoplasma gondii is a zoonotic parasite of great public health concern. Wild boars could be considered an emerging source of toxoplasmosis in humans due to the popularity of venison and their increasing population. The aim of this study was to determine the seroprevalence of T. gondii in the Slovenian wild boar population and evaluate risk factors for human infection. Of 353 samples, 62% were positive for T. gondii using ELISA tests. This is the highest T. gondii seroprevalence reported to date in wild boar worldwide. The increase in prevalence with increasing age (p = 0.003) and weight (p = 0.002) were statistically significant, whereas gender was not (p = 0.781). Odds for being T. gondii-positive increased with age with the largest difference being between 2–3-year-old and 1–2-year-old animals (OR = 2.66, 95%CI: 1.03–6.85). Animals weighing 20–40 kg had a higher risk than animals weighing 0–20 kg (OR = 2.74, 95%CI: 1.21–6.20), whereas a further increase in the weight was not associated with increasing the odds. Due to the high Toxoplasma prevalence, the study concluded that the risk of exposure to T. gondii from handling raw or undercooked wild boar meat is high. Surveillance protocols should be established at the national level together with increased awareness within the hunting community.

Occupational Hantavirus Infections in Agricultural and Forestry Workers: A Systematic Review and Metanalysis.

Hantaviruses are zoonotic pathogens that can cause serious human disorders, including hemorrhagic fever with renal syndrome and hantavirus cardiopulmonary syndrome. As the main risk factor for human infections is the interaction with rodents, occupational groups such as farmers and forestry workers are reportedly at high risk, but no summary evidence has been collected to date. Therefore, we searched two different databases (PubMed and EMBASE), focusing on studies reporting the prevalence of hantaviruses in farmers and forestry workers. Data were extracted using a standardized assessment form, and results of such analyses were systematically reported, summarized and compared. We identified a total of 42 articles, including a total of 28 estimates on farmers, and 22 on forestry workers, with a total workforce of 15,043 cases (821 positive cases, 5.5%). A pooled seroprevalence of 3.7% (95% confidence interval [95% CI] 2.2–6.2) was identified in farmers, compared to 3.8% (95% CI 2.6–5.7) in forestry workers. Compared to the reference population, an increased occurrence was reported for both occupational groups (odds ratio [OR] 1.875, 95% CI 1.438–2.445 and OR 2.892, 95% CI 2.079–4.023 for farmers and forestry workers, respectively). In summary, our analyses stress the actual occurrence of hantaviruses in selected occupational groups. Improved understanding of appropriate preventive measures, as well as further studies on hantavirus infection rates in reservoir host species (rodents, shrews, and bats) and virus transmission to humans, is needed to prevent future outbreaks.

Prevalence of antimicrobial-resistant Streptococcus species among respiratory patients and meat products, and antibacterial effects of oregano oil nanoemulsion

Background and Aim: Antimicrobial-resistant Streptococcus species causes several diseases in humans with infection recurrence in some cases. Handling of food under unhygienic conditions resulted in transmission of pathogens to food leading to risks for consumers' health. This work studies the possible role of humans in transmission of human pathogens to food products. In this study, we focused on the presence of antimicrobial resistance Streptococcus pyogenes, Streptococcus mitis, and Streptococcus pneumoniae found in respiratory patients and in some meat products. We detected the risk factors for patient's infection and examined the antibacterial effect of oregano oil nanoemulsion (ONE) at different concentrations against the multi-drug resistance strains of streptococci. Materials and Methods: Microbiological culture and polymerase chain reaction were used to identify S. pyogenes, S. mitis, and S. pneumoniae in 120 throat swab samples and 200 meat products. The disk diffusion method was used for investigating the prevalence of resistance against 10 antimicrobials that are commonly used in the treatment of humans and animals. ONE at four concentrations (0.5%, 1.0%, 2.0%, and 3.0%) with an average particle size of 45.4 nm was identified using transmission electron microscopy. The effect of ONE on Streptococcus species isolates was examined using the well diffusion method. Risk factors for human infection were detected using statistical analysis. Results: S. pyogenes, S. mitis, and S. pneumoniae were detected in 14 (11.7%), 9 (7.5%), and 7 (5.8%), respectively, of 120 throat swabs of patients. These bacteria were also detected in 11 (5.5%), 8 (4%), and 6 (3%), respectively, of 200 meat products samples. Beef luncheon had the highest infection rate for the three species of streptococci. The majority of these isolates showed resistance to antimicrobials such as tetracycline and amoxicillin/clavulanic acid. ONE had an inhibitory effect on the growth of S. pyogenes, S. mitis, and S. pneumoniae, and its effect was significantly increased at a high concentration (3%), with a mean inhibition zone of 36.45±0.302 mm. Very young and old patients, those with chronic diseases, and those exposed to the infection several times were most susceptible to infection. Conclusion: ONE may be used as a therapeutic agent at safe and specific doses, and also in the food industry, to prevent the spoilage of food and protect human health.

Leptospira spp. Antibody in Wild Boars (Sus scrofa), Hunting Dogs (Canis lupus familiaris), and Hunters of Brazil.

Hunting activities are a potential risk factor for human infection with Leptospira spp. and, although wild boar seroprevalence has been studied, there are no concurrent serosurveys of wild boars (Sus scrofa), hunting dogs (Canis lupus familiaris), and hunters. The aim of our study was to assess the seroprevalence of Leptospira spp. antibodies in free-ranging wild boars, hunting dogs, and hunters, and risk factors associated with exposure in southern and central-western Brazil. Leptospira spp. antibodies were serologically detected using the microscopic agglutination test, with a total 30 serovars. Overall, 12.2% (9/74) of wild boars and 10.6% (16/170) of hunting dogs were seropositive for at least one serovar and all hunters 0.0% (0/49) were seronegative for Leptospira spp. Seropositivity was statistically higher in 42.1% (8/19) wild boars from natural areas when compared to 2.4% (1/41) from anthropized areas (P<0.001), with prevalence ratio of 17.14 (95% confidence interval: 2.29-128.36). Despite the limited sample size, our findings showed that hunters may be less exposed to Leptospira spp. than are wild boars, particularly in natural areas where Leptospira spp. may be maintained by wild reservoirs. In addition to acting as sentinels, hunting dogs may play a role in disease transmission of sylvatic leptospiral serovars.

Surveillance of multiple subtype specific antibodies against avian influenza viruses among egg yolk in wild ducks from northeast China, 2017–2019

Over the past decade, various avian influenza viruses have been isolated from wild ducks found in the northeast of China. To monitor the prevalence of multiple subtype specific AIVs antibodies, 1705 wild ducks’ eggs from six wetlands of northeast China were analyzed for surveillance of H1, H3, H5, and H7 AIVs antibodies by c-ELISA and HI test from Jan 2017 to Dec 2019. The results show that the combined frequency of multiple subtype specific AIVs antibodies were H1 (12.32%), H3 (8.15%), H5 (2.05%), and H7 (3.46%) respectively. Therefore, a detailed analysis of the geographical distribution of AIVs in China, and the risk factors for human infection is of vital importance. This study provides basic data for other researchers to deeply study AIVs distribution characteristics, and for governments to develop detailed measures to control the spread of AIVs.

Comparative genotyping of Blastocystis infecting cattle and human in the south of Iran

BackgroundBlastocystis is a unicellular protozoan and one of the most common parasites found in humans and many animals' intestinal tract. The present study aimed to compare the genotypes of Blastocystis infecting cattle and humans in the south of Iran. MethodsA total of 100 human stool samples and 75 cattle stool samples were microscopically examined for Blastocystis infection. DNA was extracted from thirty-eight microscopically positive samples (13 humans and 25 cattle). PCR was performed on positive samples targeting the Blastocystis-specific SSU rDNA gene. PCR products of eight humans and eleven cattle samples were sequenced and compared with available reference sequences in GenBank by BLAST queries. Genetic diversity was measured for Blastocystis subtypes in human and cattle, based on haplotype and nucleotide diversities. ResultsThe PCR detected Blastocystis in ten humans and twenty-four cattle samples. Blastocystis subtypes 1, 2, and 6 were found in humans whereas subtypes 5 and 10 were found in cattle. Subtype (ST) 2 was the most predominant subtypes in humans whereas, in cattle specimens, the ST5 was the most dominant subtype. Based on the Blastocystis sequences of SSU rDNA, 68 sites were polymorphic and 49 sites were parsimony informative, resulting in the identification of 15 haplotypes, 10 haplotypes in the cattle and 5 in humans. No haplotype was shared between cattle and human parasites. ConclusionHuman-derived Blastocystis subtypes were different from cattle subtypes in southern Iran. Nevertheless, subtype 5 in cattle can be a risk factor for human infection.

Survey of Toxocara eggs on Dog Hair as a Potential Transmission Route in Human Toxocariasis in Northeastern Iran

Toxocara canis is a gastrointestinal nematode of dogs and other canids with high zoonotic potential. Human infection occurs following ingestion of infective eggs that have been passed in the dogs' feces. Contact with contaminated soils, is one of the most important risk factors for human infection by T. canis eggs. However, in recent studies transmission of infective eggs, through human contact with contaminated dogs' hair have been proposed. The aim of the present study was to assess the prevalence of Toxocara eggs on the hair and feces of dogs which attended to Veterinary Clinic of Ferdowsi University of Mashhad, Iran. A total 100 dogs which attended to the clinic were used in the present study. The hair samples were collected from the head, back and perineal region of dogs' body. Besides collecting hairs, fecal samples were also collected and analyzed for the presence of T. canis eggs. T. canis eggs were found in 11% of the hair samples and 10% of the feces samples. Additionally, it has been observed that the risk factors impact such as breed, season of sampling, sex, hair length, indoor-outdoor access and age, were not significant on the T. canis eggs presence in the faecal and hair samples. Human exposure to the hair of dogs, may be significant risk factor for infection and regular anthelmintic treatment, hygiene of animals and public education of the importance of dogs are recommended to prevent human toxocariasis.