Detection of Toxoplasma gondii oocysts in soil and risk mapping in an island environment in the Northeast of Brazil

Mapping high-risk areas for Mycobacterium tuberculosis complex bacteria transmission: Linking host space use and environmental contamination

In many Mediterranean ecosystems, animal tuberculosis (TB), caused by Mycobacterium bovis, an ecovar of Mycobacterium tuberculosis complex (MTBC), is maintained by multi-host communities. It is hypothesised that interspecies transmission is mainly indirect via shared contaminated environments. Therefore, identifying spatial areas where MTBC bacteria occur and quantifying space use by susceptible hosts might help predict the spatial likelihood of transmission across the landscape. Here, we aimed to evaluate the transmission risk of MTBC in a multi-host system involving wildlife (ungulates and carnivores) and cattle (Bos taurus). We collected eighty-nine samples from natural substrates (water, soil, and mud) at 38 sampling sites in a TB endemic area within a Mediterranean agroforestry system in Portugal. These samples were analysed by real-time PCR to detect MTBC DNA. Additionally, host-specific space use intensity maps were obtained through camera-trapping covering the same sampling sites. Results evidenced that a significant proportion of samples were positive for MTBC DNA (49 %), suggesting that the contamination is widespread in the area. Moreover, they showed that the probability of MTBC occurrence in the environment was significantly influenced by topographic features (i.e., slope), although other non-significant predictor related with soil conditions (SMI: soil moisture index) incorporated the MTBC contamination model. The integration of host space use intensity maps with the spatial detection of MTBC showed that the red deer (Cervus elaphus) and wild boar (Sus scrofa) exhibited the highest percentages of high-risk areas for MTBC transmission. Furthermore, when considering the co-occurrence of multiple hosts, transmission risk analyses revealed that 26.5 % of the study area represented high-risk conditions for MTBC transmission, mainly in forest areas.

Parasites and Viruses in Callithrix in Brazil

PURPOSE

As a result of environmental imbalances of anthropogenic origin, the potential for transmission of parasites and viruses between different primates, including humans, might increase. Thus, parasitic studies have great relevance to primatology, which motivated us to conduct a literature review to synthesize the information available in American primates of the Callithrix genus.

METHODS

We carried out the bibliographic search on the main groups of parasites (protozoa, helminths, arthropods, ectoparasites) and viruses found in Callithrix in Brazil in search platforms and consider all manuscript that appeared in search engines, published between the years 1910 and December 2022. In each selected article, the following information was recorded: the host species; parasite taxa; scientific classification of the parasite; host habitat (free-living, captive); diagnostic technique; state; and bibliographic reference. Data were tabulated and arranged in a parasite-host table.

RESULTS

Some endemic genera, such as Callithrix, are widely distributed geographically across Brazil and have characteristics of adaptation to different habitats due to their flexibility in diet and behavior. These factors can make them subject to a greater diversity of parasites and viruses in the country. Here, we identified 68 parasitic taxa, belonging to the clades protozoa (n = 22), helminths (n = 34), ectoparasites (n = 7), and viruses (n = 5). Out of this total, 19 have zoonotic potential. Of the six existing marmoset species, Callithrix jacchus was the most frequent in studies, and Callithrix flaviceps did not have reports. All regions of the country had occurrences, mainly the Southeast, where 54% of the cases were reported. In 46% of the reported parasites and viruses, it was not possible to identify the corresponding species.

CONCLUSION

We conclude that in part of the works the identification methods are not being specific, which makes it difficult to identify the species that affects Callithrix spp. Furthermore, the studies present geographic disparities, being concentrated in the southeast of the country, making it impossible to have a more uniform analysis of the findings. Thus, it is observed that information about parasites and viruses is incipient in the genus Callithrix in Brazil.

Brucellae as resilient intracellular pathogens: epidemiology, host-pathogen interaction, recent genomics and proteomics approaches, and future perspectives

Brucellosis is considered one of the most hazardous zoonotic diseases all over the world. It causes formidable economic losses in developed and developing countries. Despite the significant attempts to get rid of Brucella pathogens in many parts of the world, the disease continues to spread widely. Recently, many attempts proved to be effective for the prevention and control of highly contagious bovine brucellosis, which could be followed by others to achieve a prosperous future without rampant Brucella pathogens. In this study, the updated view for worldwide Brucella distribution, possible predisposing factors for emerging Brucella pathogens, immune response and different types of Brucella vaccines, genomics and proteomics approaches incorporated recently in the field of brucellosis, and future perspectives for prevention and control of bovine brucellosis have been discussed comprehensively. So, the current study will be used as a guide for researchers in planning their future work, which will pave the way for a new world without these highly contagious pathogens that have been infecting and threatening the health of humans and terrestrial animals.