Leishmaniasis is a widespread but still underdiagnosed parasitic disease that affects both humans and animals. There are at least 20 pathogenic species of Leishmania, most of them being zoonotic. The diagnosis of leishmaniasis remains a major challenge, with an important role being played by the species of parasites involved, the genetic background, the immunocompetence of the host. This paper brings to the fore the sensitivity of the balance in canine and human leishmaniasis and addresses the importance of the host’s immune response in establishing a correct diagnosis, especially in certain cases of asymptomatic leishmaniasis, or in the situation the host is immunosuppressed or acquired leishmaniasis through vertical transmission. The methods considered as a reference in the diagnosis of leishmaniasis no longer present certainty, the diagnosis being influenced mostly by the immune response of the host, which differs according to the presence of other associated diseases or even according to the breed in dogs. Consequently, the diagnosis and surveillance of leishmaniasis cases remains an open topic, requiring new diagnostic methods adapted to the immunological state of the host.

(1) Background: Few studies to date have assessed the influences induced by climate change on the spatial distribution and population abundance of Aedes albopictus using the latest climate scenarios. In this study, we updated the current distribution of Ae. albopictus mosquitoes and evaluated the changes in their distribution under future climate conditions, as well as the risk of dengue virus emergence in Romania. (2) Methods: Under the two scenarios: High scenario (HS) when no drastic measures to reduce the effects of global warming will be taken, or they are not effective and low scenario (LS) when very stringent greenhouse control measures will be implemented. (3) Results: The results estimate an increase in temperatures in Romania of up to 2.6 °C in HS and up to 0.4 °C in LS, with an increase in the period of virus replication within the vector from June to October in HS and from May to September in LS. Moreover, in 2022, Ae. albopictus was reported in a new county, where it was not identified at the last monitoring in 2020. (4) Conclusions: The rapid spread of this invasive species and the need to implement monitoring and control programs for the Aedes population in Romania are emphasized.

This study describes granulocytic anaplasmosis in two dogs naturally infected with Anaplasma phagocytophilum. The 3-year-old dogs (male and female) came from the same household and were referred to the Faculty of Veterinary Medicine in Iasi for blood donation. They were subject to standard routine tests: haematology blood test, blood smear, and serological tests (VETSCAN^® FLEX4 and IDEXX SNAP 4Dx Plus). The female dog had no medical problems, while the male dog experienced joint pain. The blood smear was negative for tick-borne pathogens, and the haematology findings indicated thrombocytopenia in both dogs, with the male dog also displaying eosinophilia. The two dogs were mildly positive in the ELISA tests for the detection of Anaplasma spp. antibodies; therefore, the blood samples were tested using the qRT-PCR method for Anaplasma platys and Anaplasma phagocytophilum. The qRT-PCR result was negative for A. platys, but it was positive for A. phagocytophilum. The treatment consisted of the administration of doxycycline for 28 days. In conclusion, the high number of cases with non-specific clinical signs, the different sensitivity and specificity of the immunochromatographic serological tests, as well as the possibility of confusing the morula during the cytological examination, make the molecular test mandatory for precise diagnosis.

Dirofilariosis, a parasitic disease caused by nematodes of the genus Dirofilaria, primarily affects dogs but can also infect other carnivores and, more rarely, humans. In Europe, the most commonly involved species are D. immitis and D. repens, transmitted through the bites of mosquito vectors. This study, conducted in Tulcea County between April and October 2024, aimed to determine the prevalence of D. immitis and D. repens in mosquitoes. A total of 1507 mosquitoes were collected and grouped into 76 pools, and subsequently molecular analysis was carried out using qPCR. The estimated infection rate (EIR) was calculated using statistical methods available in the ‘binGroup’ package in R, which allow the determination of the point estimate and confidence interval (CI) for a single binomial proportion in group testing. The study revealed a high infection rate with D. immitis (48%), while D. repens was identified in only two pools. The species with the highest vector potential was Anopheles maculipennis (PTP = 75%, EIR = 0.1168 with both Dirofilaria species), followed by Aedes vexans. Notably, Aedes albopictus was identified for the first time in Tulcea, and all individuals were positive for D. immitis. Simulations of local thermal conditions using the proposed model show that the favorable time window for mosquitoes will increase until 2100. Our results indicate an established and active transmission cycle of D. immitis in the region, a situation projected to intensify with climate change requiring urgent monitoring.

Laboratory diagnosis of leishmaniasis remains a major challenge, demonstrating variable efficacy in detecting infected mammalian hosts. Thus, there is a great need for the accuracy of the identification of appropriate antigens to also improve diagnostic tests. This review brings to the fore the sensitivity of the balance in canine and human leishmaniasis, which greatly influences the progression of the disease and especially the diagnostic methods. The problem of diagnosis arises in asymptomatic leishmaniasis, since in these conditions the methods considered as reference in the diagnosis of leishmaniasis no longer show certainty, being influenced for the most part by the immune response of the host, which is different according to the presence of other associated diseases or even according to the breed, when we talk about dogs. Consequently, the diagnosis and surveillance of leishmaniasis cases remains an open topic, with the need for new methods adapted to the immunological status of the host.

More zoonotic infections are carried by ticks than by any other kind of vector, and they are prevalent on all continents. Since all vector-borne diseases species have been affected by climate change detected in recent years, an important number of vector species (ticks, mosquitoes, fleas, sand-flies, etc.), and the pathogens they carry are currently expanding in both distribution and incidence, with significant implications for human and animal health and welfare. Therefore, the aim of this retrospective study was to determine the main vector-borne diseases identified in 45 canine patients with or without specific symptoms from Iasi County, between March 2023 and December 2025. Molecular screening was performed using multiplex quantitative real-time PCR (qPCR) instrument, being able to detect the DNA of more than 19 pathogens specific to dogs. The main species of pathogens requested by veterinarians (Babesia spp., Babesia canis, Babesia gibsoni, Babesia vogeli, Anaplasma/Ehrlichia spp., Mycoplasma haemocanis, Hepatozoon canis, Dirofilaria immitis, Borrelia spp., or Leptospira spp.) were detected in 51.12% of the samples analyzed. The molecular results showed that the most prevalent vector-borne species detected in canine blood were: Babesia spp. (30.43%; 7/23), followed by Babesia gibsoni (17.39%; 4/23), Babesia vogeli (8.7%; 2/23), Babesia canis (4.35%; 1/23), Hepatozoon canis (4.35%; 1/23), Dirofilaria immitis (4.35%; 1/23), Anaplasma/Ehrlichia spp. (4.35%; 1/23), and Mycoplasma haemocanis (4.35%; 1/23). Even though Leptospira is not part of the group of vector-borne diseases, it is an important zoonotic pathogen, and the high number of cases detected in dogs (21.73%; 5/23) raises numerous concerns regarding biosecurity measures in veterinary clinics, as well as insufficient prophylactic measures. These results underline the necessity of constant monitoring of vector-borne and zoonotic infections, being essential to both veterinary and human medicine within a One Health framework.