In the wake of Portugal's pivotal shift to animal welfare legislation in 2018, where the no-kill policy for population control came into effect, animal shelters have emerged as critical sanctuaries for stray or unwanted animals. Recognising the critical role that adopter preferences play in the successful placement of shelter animals and the pressing need for shelters to expedite adoptions to liberate valuable space to accommodate more animals in need of refuge, this study seeks to investigate the intricate matrix of factors guiding adopters' choices. A descriptive cross-sectional study was performed with a convenience sample of the Portuguese population to assess their preferences and opinions about pet adoption. An online questionnaire was completed by 415 participants from February to October 2021. Among participants selecting attributes for pet adoption, the top preferences were behaviour (52.8%), size (49.6%), vaccination and deworming status (44.3%), and age (36.1%). Conversely, breed (7.2%), sex (6.3%), and animal colour (5.1%) were the least prioritised. Combinations were established based on the most selected attributes. Certain participant characteristics, such as education level and pet ownership history, exhibited distinct preferences in animal attributes. Portuguese people show a marked preference for shelter adoption, prioritising behaviour, size, and health over breed and colour. This insight allows shelters to allocate resources effectively. While promising, the trend towards shelter adoption needs adaptive strategies to align with evolving adopter preferences.

Canine leishmaniosis (CanL) is a chronic, systemic and often severe disease. The main causative agent of CanL is a protozoan parasite, Leishmania infantum, with phlebotomine sand flies acting as vectors. In Europe and other continents, L. infantum is also responsible for leishmaniosis in other animals, such as cats, horses and humans. In Portugal, animal and human leishmanioses are endemic, and high prevalence levels of infection and disease have been reported in dogs. There is a prejudice against stray animals and also those housed in shelters, assuming they have higher levels of infection with vector-borne pathogens, including L. infantum, when compared to domestic animals. In north-eastern Portugal, serum samples were obtained from March to May 2022 in three shelters (n = 179) and 13 veterinary clinics (n = 164), resulting in 343 dogs being analysed for antibodies to Leishmania spp. by the direct agglutination test (DAT). The overall seroprevalence was 9.9%, with 15.2% seroprevalence in domestic dogs and 5.0% in the shelter ones (p = 0.003). The fact that shelter dogs had a lower seroprevalence could be explained by more regular veterinary care provided in shelters regarding preventive measures, including insecticides with an antifeeding effect, in comparison with domestic dogs.

A cross-sectional study was conducted to gain insight into the epidemiology of canine ehrlichiosis and rickettsiosis in northern Portugal. Specific IgG antibodies to Ehrlichia canis were analysed using a commercial indirect ELISA test, and antibodies to Rickettsia conorii using a commercial IFAT. A total of 113 dogs from two different shelters were sampled, and seroprevalence values of 0.9% (95% confidence [CI]: 0.2–4.8%) for E. canis and 9.7 (95% CI: 5.5–16.6%) for R. conorii were found. Univariable models investigated risk factors for seropositivity. The odds ratios (OR) of R. conorii seropositivity were higher for female dogs (OR = 2.32; 95% CI: 1.58–3.39) and for dogs belonging to Shelter 2 (OR = 3.0; 95% CI: 2.28–3.95). Seropositive dogs for co-infection (E. canis + R. conorii) were more frequently observed in females (OR = 2.4; CI 95%: 1.66–3.47) and in Shelter 2 (OR = 2.72; 95% CI: 1.97–3.76). These findings show that shelter dogs in northern Portugal are exposed to E. canis and R. conorii, which can affect both canines and humans. It is imperative to adopt a One Health approach to educate the public about the hazards of canine zoonoses and develop legislation and procedures to control their spread and preserve public health.

West Nile virus (WNV) is an arbovirus mainly transmitted by Culex spp., which causes a worldwide zoonotic disease. This pathogen is endemically maintained in a life cycle with birds acting as reservoirs and humans and horses as accidental and dead-end hosts. Sporadic WNV outbreaks have been reported in Europe and the potential impact of WNV infection on populations of threatened or endangered birds of prey is considerable. Surveillance programs are needed for early detection of this virus. All four species of vultures present in Europe are considered protected species. As scavengers, vultures are at the top of the food chain, and can be susceptible to and negatively affected by pathogens like WNV. In a conservation perspective, the impact of WNV in European vultures, alone or concomitantly with other factors, should be addressed. This review of documented cases can be considered a state point.

Pet ownership is common in modern society. In Portugal, 38% and 31% of all households own, at least, one dog or cat, respectively. Few studies have ascertained the knowledge of pet owners about pet ownership and zoonoses, and none of them was carried out in Portugal. The aim of the present study was to assess household knowledge and practices related to pet ownership and zoonoses in the North of Portugal. A questionnaire was completed by 424 pet owners, during November 2019 to February 2020. Most respondents (97.2%) considered pets as an important part of the family, especially women (p = 0.036); 73.1% allowed their pets free access to indoors; 41.3% denied sharing the bed with their pets and 29% assumed they did it daily; 20.3% reported never kissing their pets/pets licking their faces; 73.6% considered animals as potential sources of diseases to humans, but only 25.9% reported knowing the definition of zoonoses; 96.9% considered important the role of veterinarians in protecting public health. The low level of knowledge of pet owners and the occurrence of high-risk behaviors indicate a need to strengthen communication between veterinarians, physicians, pet owners and the general public to reduce the risk of acquisition and transmission of zoonoses.

Hepatitis E virus (HEV) is a zoonotic foodborne virus with an annual infection prevalence of 20 million human cases, which seriously affects public health and economic development in both developed and developing countries. To better understand the epidemiology of HEV in the Centre of Portugal, a cross-sectional study was conducted from 2016 to 2023 with sera samples from wild ungulates. The seroprevalence and risk factors for HEV seropositivity were evaluated in the present study. Specifically, antibodies against HEV were determined by a commercial enzyme-linked immune-sorbent assay (ELISA). Our results show that in the 650 sera collected from 298 wild red deer and 352 wild boars from Portugal, 9.1% red deer (95% confidence interval [CI]: 6.312.9%) and 1.7% wild boar (95% CI: 0.63.3%) were positive for antibodies to HEV. Regarding age, the seropositivity in juvenile wild ungulates was 1.3% (95% CI: 0.273.72%) and 7.2% in adults (95% CI: 4.910.11%). Logistic regression models investigated risk factors for seropositivity. The odds of being seropositive was 3.6 higher in adults than in juveniles (95% CI: 1.7218.11%) and the risk was 4.2 higher in red deer than in wild boar (95% CI: 1.64–10.69%). Both wild ungulate species were exposed to HEV. The higher seroprevalence in red deer suggests that this species may have a major contribution to the ecology of HEV in the Centre of Portugal. Further research is important to understand how wildlife affects the epidemiology of HEV infection in Portugal.

Paratuberculosis, or Johne's disease, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic granulomatous enteritis affecting both domestic and wild ruminants. The agent was also found in wild mammals such as wild boar (Sus scrofa), however, the role of wild mammals in the epidemiology of MAP is unclear. During the research period, 941 free-ranging wild boar (S. scrofa) legally hunted in two locations in the Centre-eastern region of Portugal were examined. Ninety-seven wild boar exhibited one or more gross lesions and were tested for the presence of Mycobacterium avium subsp. paratuberculosis using acid-fast staining, mycobacterial culture, poly-merase chain reaction (PCR), and histopathological examination. Forty-five animals (46.4%, 95% CI: 36.5-56.3%) were identified as infected, as indicated by positive results in culture and/or PCR. The findings revealed that the most significant risk factor was being a juvenile compared to year-lings and adults (OR = 10.2, 95% CI: 2.2-48.0). Based on our results, 37.9% (n = 11) of the infected animals were considered suitable for human consumption. Our findings offer novel insights into mycobacterial infections in wild boar populations in Portugal and suggest that wild boar could be a source of human infection if zoonotic potential is considered.

Emerging infectious diseases are a major threat to biodiversity and an important public health issue. West Nile virus (WNV) is an emerging vector-borne zoonotic arbovirus that is currently broadening its distribution in Europe. The evidence of WNV circulating in resident and migratory species has implications for both animal and public health, and should therefore be studied in depth. An integrated surveillance program, namely in birds, is essential for reducing the risk of infection in human populations within the One Health principles. In the present study, wild birds admitted to wildlife rehabilitation centres in Portugal were sampled. Two-hundred and eight blood samples were assayed serologically to antibodies to WNV, by using a commercial ELISA kit. An overall seroprevalence of 19.6% (95% confidence interval [CI]: 13.7-26.7%) was observed. Antibodies to WNV were detected in 13 (35.1%) different species of wild birds. Accipitriformes (26.7%; 95% CI: 18.5-36.2%) and Strigiformes (26.7%; 95% CI: 14.6-42.0%) were the orders with the highest seroprevalence recorded. There were no statistically significant differences (p = 0.725) between the geographical regions (NUTS II) studied, but statistically significant difference (p = 0.017) was found between gender (male: 34.4%; female: 4.8%). A higher seroprevalence was found in adults (32.1%) compared to juvenile birds (9.3%) (p = 0.014), and age was considered a risk factor to WNV infection in wild birds (odds ratio 1.4; 95% CI: 0.5–4.0). More epidemiological studies are needed in Portugal, since the actual spread of the WNV throughout the country is unknown.