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Coxiella burnetii is the etiologic agent of Q fever, a worldwide zoonosis. Cattle, sheep and goats are considered the main reservoirs of the disease. Transmission to humans occurs mainly through the inhalation of infectious aerosols from milk, faeces, urine, and birth products from infected ruminants. In this study, a 2-year longitudinal approach was performed to ascertain the excretion of C. burnetii in bulk tank milk samples of sheep from a mountain plateau in central Portugal, with sampling conducted during the years 2015 and 2016. From a total of 156 bulk tank milk samples tested by qPCR, only one showed to be positive for C. burnetii (1.28% [95%CI: 0.03-6.94]), from 2015, the first year of collection. Bidirectional sequencing and phylogenetic analysis of IS1111 transposase partial region confirmed the presence of C. burnetii DNA. The presence of C. burnetii in raw milk samples highlights the necessity for additional research to determine if raw milk is a potential source for human infection. Animal health surveillance and prevention measures against this zoonotic disease should be considered., (© 2024. The Author(s).)

Coronavirus disease-19 (COVID-19) is caused by the severe acute Respiratory syndrome coronavirus-2 (SARS-CoV-2), which has become unstoppable, spreading rapidly worldwide and, consequently, reaching a pandemic level. This review aims to provide the information available so far on the likely animal origin of SARS-CoV-2 and its possible hosts/reservoirs as well as all natural animal infections and experimental evidence using animal models. Horseshoe bats from the species Rhinolophus affinis seem to be a natural reservoir and pangolins (Manis javanica) appear to be an intermediate host of SARS-CoV-2. Humans remain the most likely spreading source of SARS-CoV-2 to other humans and also to domestic, zoo and farm animals. Indeed, human-to-animal transmission has been reported in cats, dogs, tigers, lions, a puma and minks. Animal-to-human transmission is not a sustained pathway, although mink-to-human transmission remains to be elucidated. Through experimental infections, other animals seem also to be susceptible hosts for SARS-CoV-2, namely ferrets, some non-human primate species, hamsters and transgenic mice, while dogs, pigs and poultry are resistant. A One Health perspective must be implemented in order to develop epidemiological surveillance and establish disease control mechanisms to limit zoonotic transmission. Moreover, research in this field is important to better understand SARS-CoV-2 and to obtain the long-awaited vaccine and specific treatment.

Toxoplasmosis is a global zoonosis caused by the protozoan parasite Toxoplasma gondii. Detection of antibodies to T. gondii in serum samples from hunted animals may represent a key step for public health protection. It is also important to assess the circulation of this parasite in wild boar population. However, in hunted animals, collection of blood is not feasible and meat juice may represent an alternative sample. The purpose of the present study was to evaluate heart meat juice of hunted wild boars as an alternative sample for post-mortem detection of antibodies to T. gondii by modified agglutination test (MAT). The agreement beyond chance between results from meat juice assessed with Cohen's kappa coefficient revealed that the 1:20 meat juice dilution provided the highest agreement. McNemars's test further revealed 1:10 as the most suitable meat juice dilution, as the proportion of positive paired samples (serum and meat juice from the same animal) did not differ at this dilution. All together, these results suggest a reasonable accuracy of heart meat juice to detect antibodies to T. gondii by MAT and support it as an alternative sample in post-mortem analysis in hunted wild boars.

Streptococcus pneumoniae is the agent responsible for infections such as pneumonia, otitis media, and meningitis. Among virulence factors, the Pneumococcal surface protein A (PspA) has been shown to be immunogenic and protective in mice, and is thus a good vaccine candidate. PspA has been classified into 6 clades and 3 families. Initially, pspA fragments, clades 1 and 3, were cloned into the pAE-6His expression vector. Proteins were expressed in Escherichia coli BL21(DE3) and purified by affinity and anion exchange chromatographies, with a yield of 11 mg/l of culture. Due to plasmid instability in E. coli, another construct using pspA1 was obtained based on pET-37b(+), which was shown to be stable in E. coli and increased the yield approximately 3-fold. Our results show good conditions for scale-up. Sera from immunized mice recognized PspA in total extracts of S. pneumoniae strains: anti-rPspA1p sera recognized native PspA clades 1 (+++), 2 (++) and 4 (+) and anti-rPspA3p sera recognized PspA clades 1 (+), 2 (+), 3 (+++) and 4 (+). The cross-reactivity pattern obtained confirms the notion that proteins from both families should be included for development of a broad-coverage vaccine; lower-cross reactivity between rPspAs of family 2 indicates that it may be necessary to include 2 proteins from this family.