Journal of Zoonotic Diseases
Volume:8 Issue: 3, Summer 2024

Climate change is the twenty-first century's most significant threat to human health. Human activity has led to a gradual increase in greenhouse gas concentrations, resulting in global warming and other related hazards. Climate change is significantly impacting ecosystems and biodiversity, leading to a potential increase in zoonotic diseases. Zoonoses are infectious diseases that are transmitted among animals and humans. Vector-borne, foodborne, and waterborne diseases are major infectious diseases associated with climate change. Changes in temperature and precipitation patterns influence the survival, reproduction, and activity of disease-carrying vectors like mosquitoes, ticks, and sandflies. Variations in climate can affect the spread of diseases such as malaria, leishmaniasis, and rodent-borne illnesses like leptospirosis, bartonellosis, plague, and hantavirus infections. Climate change can also impact waterborne illnesses by altering water quality and increasing the risk of contamination during natural disasters. Additionally, higher temperatures and increased humidity can cause transmission of airborne zoonotic diseases, such as aspergillosis, tuberculosis, and influenza. The evolving climate may also contribute to the development of resistance in disease-causing microorganisms, making treatment more challenging. Human behavior influenced by climate change, such as changes in agricultural practices and land use, can indirectly affect disease transmission by altering vector habitats and human-animal interactions. Overall, the complex interplay between climate change, ecological factors, and human behavior underscores the need for comprehensive strategies to mitigate the risks posed by zoonotic diseases and protect public health.

Staphylococcus aureus (S. aureus) infections in livestock and humans pose serious health problems. Therefore, identifying the virulence genes of this bacterium and studying their characteristics are of great importance. The main objective of this study was to investigate the frequency of virulence (enterotoxin) genes of S. aureus isolated from sheep noses in the Sistan region. In this study, 100 isolates of S. aureus were collected. After genomic extraction of the identified isolates, a multiplex PCR reaction was performed for sea, seb, sec, see, tsst, and pvl genes using specific primers. In total, 49 isolates of S. aureus isolated contained one or more enterotoxin genes. The most abundant gene was tsst (37%), followed by sec (23%), seb (20%), and sea (2%). In general, it was found that the presence of S. aureus in sub-clinical animal isolates, especially enterotoxigenic strains, can be a potential health hazard.

Brucellosis is a communicable zoonotic disease that is endemic in Eastern Africa and other countries, humans contracted this infection from diseased animals. This study aimed to evaluate the seroprevalence and risk factors associated with brucellosis in dromedary camels and the knowledge, attitude, and practice of camel owners regarding brucellosis at the human-animal interface that could endanger humans in the study area. A cross-sectional study determined the seroprevalence of camel brucellosis in 404 camels. A questionnaire survey involving 120 participants was also conducted to assess the knowledge, attitude, and practice of camel owners regarding the disease. The seroprevalence of camel brucellosis was estimated as 6% by the Rose Bengal plate test and 0.5% (95% CI: 0.1-1.8) by indirect enzyme-linked immunosorbent assay (iELISA). Pastoralists are in close contact with their animals, and the consumption of raw milk and handling of abortive material is common, which exposes them to a higher risk of infection. The questionnaire survey indicated that about 40% of respondents had previous knowledge about the disease. Almost, 17% and 40% knew that the disease can be transmitted from camel to humans and between camels, respectively. About 67.5% of the respondents disposed of aborted fetuses and placenta in the open field and 86.7% of the respondents consumed raw milk. This indicates that an awareness campaign is important to equip pastoral communities in the study areas with knowledge about the disease and change their malpractice to protect themselves from brucellosis. Qualitative and quantitative research methods were used in the study. The present study revealed a low seroprevalence (0.5%). Although the seropositive animals in this study appeared to be healthy, the results indicated that the disease may manifest as a carrier and adversely affect productivity and public health.

Production-limiting diseases, such as helminth infections, are a major concern in temperate regions. They can lead to decreased meat and milk production and quality in livestock. This investigation aimed to assess the prevalence of Fasciola spp., Dicrocoelium spp., and Cystic echinococcosis in different livestock species (cattle, sheep, and goats) at the Khorramabad slaughterhouse between March 21, 2012, and March 20, 2022.ANOVA was employed to assess how disease prevalence varies across different periods and among various livestock species, aiming to comprehend the interplay of these independent variables on disease prevalence. The highest prevalence of Fasciola spp. was related to cattle, with a seasonal pattern showing a higher prevalence in autumn and winter. Hydatid cysts have increased over the past decade, with D. dendriticum being prevalent from 2017 to 2020. The investigation conducted has provided evidence that diseases caused by parasitic infestations in ruminants continue to persist even after treatment. This highlights the need for more effective and targeted sanitary and preventive measures that consider the type of parasite and its prevalence during different seasons. It is hence important to design and implement measures tailored to the specific needs of each parasite species, and aligned with the seasonal fluctuations in its population. This will help minimize the risk of disease transmission, thus reducing the impact on animal health and productivity, ultimately benefitting the livestock industry as a whole.

Pathogenic bacteria are the cause of many human food poisonings during the consumption of contaminated poultry products. This study was conducted to investigate the difference in the microbial load of poultry carcasses slaughtered at different temperatures in water chillers in the slaughterhouses of Kohgiluyeh and Boyer-Ahmad provinces, Iran. One hundred twenty samples were taken randomly, under sterile conditions from chillers with temperatures of 24, 10, and 4 °C. The total count of microorganisms and bacterial isolation was done according to the national standard of Iran. The results showed that 3.3% of the samples were above the permissible limit in terms of the number of microorganisms, and all the positive samples belonged to chillers with a temperature of 24 °C. Furthermore, 28.3% of the samples were positive for contamination with E. coli and the highest contamination belonged to the first chiller (24 °C). In addition, 16.2% of the samples were reported to be positive for Salmonella spp. This study showed that the cooling steps significantly (p < 0.05) decreased the number of microorganisms, E. coli and Salmonella spp. E. coli and Salmonella bacteria could be isolated from the studied poultry carcasses at all stages. Although the microbial load of carcasses decreases after cooling in chillers, due to cross-contamination with some bacteria, such as E. coli and Salmonella spp., there is a need to comply with health standards to modify the slaughter process and use other kinds of chillers that are not less carcasses combination such as air chillers instead of water chillers. Besides, as the Salmonella spp. Sources are mainly from the intestinal should special attention be paid to the discharge of internal organs during the slaughtering process and the reduction of Salmonella spp. Contamination during the breeding period in broiler farms.

Toxoplasmosis is an important health concern for people and farm animals, leading to many studies on its effects on these populations. Despite this, there is a lack of research on the prevalence of Toxoplasma gondii infection among horses in Iran. This study aims to determine the seroprevalence of toxoplasmosis using the Modified Agglutination Test (MAT) in northwest Iran horses. In this study, blood samples were taken from 385 horses in Ardabil, East Azerbaijan, and West Azerbaijan provinces. Data regarding the age, gender, and location of each horse was documented to assess their impact on the prevalence of toxoplasmosis. The data was analyzed using the chi-square test, with a significance level of p < 0.05. Of the 385 samples, 34 (8.8%) were positive for Toxoplasma gondii. Among the 271 male and 114 female horses, 24 (8.9%) and 10 (8.8%) were seropositive, respectively. Of the 116 horses under and 269 over five years old, 15 (12.9%) and 19 (7.1%) were seropositive, respectively. The prevalence rates in Ardabil, East Azerbaijan, and West Azerbaijan were 11.7% (18 out of 154), 5.1% (7 out of 136), and 9.5% (9 out of 95), respectively. According to the statistical analysis, there were no significant differences in the prevalence of Toxoplasma gondii infection based on age, gender, or sampling location. This study is the first extensive report on the toxoplasmosis seroprevalence among horses in northwest Iran. The results provide important information that can help control and prevent the spread of toxoplasmosis.