ETIDIOH - NEW

  {Summary} -- During current epidemiological week ( 11– 17 September 2025),  65 new confirmed human cases of infection with West Nile Virus have been reported.  -- The total number of confirmed cases , since the beginning of the epidemic season, has thus risen to 647 (it was 582 last week), of these:  - 300 were West Nile Neuroinvasive Disease (WNND): 15 in Piedmont, 39 Lombardy, 24 Veneto, 2 Friuli-Venezia Giulia, 1 Liguria, 23 Emilia-Romagna, 5 Tuscany, 83 Latium, 2 Molise, 77 Campania, 2 Apulia, 2 Basilicata, 5 Calabria, 1 Sicily, 19 Sardinia,  - 54 were asymptomatic cases detected among blood donors ,  - 284 were West Nile Fever cases (one imported from Kenya),  - 3 asymptomatic cases and  - 6 unspecified casese.  -- Among confirmed cases, there were 47 death cases : 7 in Piedmont, 5 Lombardy, 1 Emilia-Romagna, 16 Latium, 15 Campania, 2 Calabria, 1 Sardinia.  - The Case-Fatality Rate in WNND cases was 15.8% (it was 20% in 2018 and...

  Abstract Mosquito-borne diseases are deeply embedded within ecological communities, with environmental changes—particularly climate change—shaping their dynamics . Increasingly intense droughts across the globe have profound implications for the transmission of these diseases , as drought conditions can alter mosquito breeding habitats , host-seeking behaviours and mosquito–host contact rates . To quantify the effect of drought on disease transmission, we use West Nile virus as a model system and leverage a robust mosquito and virus dataset consisting of over 500 000 trap nights collected from 2010 to 2023, spanning a historic drought period followed by atmospheric rivers. We pair this surveillance dataset with a novel modelling approach that incorporates monthly changes in bird host community competence , along with drought conditions , to estimate the effect of drought severity on West Nile virus risk using panel regression models. Our results show that while drought decreases ...

  Abstract Climate change is increasingly recognized as a major driver of emerging infectious diseases, particularly vector-borne diseases (VBDs), which are expanding in range and intensity worldwide. Europe , traditionally considered low-risk for many arboviral infections , is now experiencing autochthonous transmission of pathogens such as dengue, chikungunya, Zika virus, West Nile virus, malaria, and leishmaniasis . Rising temperatures , altered precipitation patterns , and milder winters have facilitated the establishment and spread of competent vectors , including Aedes, Anopheles, Phlebotomus, and Culex species , in previously non-endemic areas. These climatic shifts not only impact vector survival and distribution but also influence vector competence and pathogen development , ultimately increasing transmission potential. This narrative review explores the complex relationship between climate change and VBDs, with a particular focus on pediatric populations . It highlights h...

Abstract Background :  The Liao ning virus (LNV), belonging to the genus Seadornavirus within the family Sedoreoviridae , is a mosquito-borne virus . It was originally isolated from Aedes dorsalis mosquitoes in China . The original LNV strain, LNVS-NE97-31, was reported to infect several mammalian cell lines and cause hemorrhagic symptoms in mice . Subsequently, another LNV strain, LNV NSW B115745, was isolated from Australian mosquitoes ; it was reported to exhibit insect-specific infection. Materials and Methods :  Virus isolation was performed on mosquitoes collected in northern Hokkaido, Japan, in 2022 . The isolated virus was subjected to genomic and growth kinetics analyses. Results :  A LNV strain was isolated from Aedes vexans mosquitoes . Genomic sequencing and phylogenetic analysis revealed the new strain as 22WN03, and it formed a robust clade with the original Chinese strain, LNVS-NE97-31. Growth kinetics analysis did not reveal any mammalian or avian cell lin...

{Excerpts} During the epidemiological week comprised between 24 and 30 July 2025, there were fifty-seven new confirmed cases of human infection with West Nile Virus . -- Since the start of the epidemic season, eighty-nine cases have been reported (there were thirty-two cases in the last week report), of which: -- forty were WNND (West Nile Neuroinvasive Disease): - 2 cases in Piedmont, 1 Lombardy, 3 Veneto, 1 Emilia-Romagna, twenty-three Latium, ten Campania); -- two cases of asymptomatic infection were detected among blood donors (one in Veneto and one in Campania); -- forty-six cases of West Nile Fever have been confirmed:  - one in Lombardy, five in Veneto, thirty-five in Latium, four in Campania, one in Sardinia; -- one asymptomatic case is from Campania; -- Among confirmed cases, eight fatalities have been recorded: one in Piedmont, two in Latium and five in Campania. The case-fatality rate among WNND so far is at 20% (during epidemic seasons 2018 it was 20% and in 2024, 14%)....

{Summary} -- During the Week 17-23 July 2025, Italy reported twenty-seven new cases of human infection with West Nile Virus. -- Since the beginning of the epidemic season, thirty-two confirmed human WNV infection cases have been reportede (there were five cases in the last update), of these: - twenty-three were West Nile Neuroinvasive Disease (WNND): 2 in Piedmont, 2 in Veneto, 1 Emilia-Romagna, 15 Latium, 3 Campania), - one asymptomatic case was detected in a blood donor (Veneto), - six cases of West Nile Fever have been reported (2 in Veneto, 4 Latium), and two asymptomatic cases (Latium), - among the cases, there were two fatalities (1 in Piedmont, 1 in Latium). -- The first confirmed case of the season was detected in Piedmont Region on March 20 2025 (sporadic case), then in Novara Province (July 3rd). -- No confirmed cases of Usutu Virus infection have been detected so far. (...) Source: Istituto Zooprofilattico Sperimentale di Teramo,  https://westnile.izs.it/j6_wnd/home ____...

Abstract Neuroinvasive arboviruses such as tick-borne encephalitis virus (TBEV), West Nile virus (WNV), Usutu virus (USUV), and Toscana virus (TOSV) have (re-)emerged with increasing incidence and geographic range . We analyzed the epidemiology of arboviral infections in Croatia during the 2024 transmission season. A total of 154 patients with neuroinvasive diseases (NID), 1596 horses , 69 dead birds , and 7726 mosquitoes were tested. Viral RNA was detected using RT-qPCR. IgM/IgG-specific antibodies were detected using commercial ELISA or IFA, with confirmation of cross-reactive samples by virus neutralization test. RT-qPCR-positive samples were Sanger sequenced. Arboviral etiology was confirmed in 33/21.42% of patients with NID. WNV was most frequently detected (17/11.03%), followed by TBEV (10/6.49%), USUV (5/3.24%), and TOSV (1/0.64%). WNV infections were reported in regions previously known as endemic, while in one continental county, WNV was recorded for the first time. USUV infec...

Summary Background Malaysia is one of the southeast Asian countries hardest hit by dengue . We implemented a proactive integrated vector management (IVM) approach in a large non-blinded, cluster-randomised controlled trial to quantify its effectiveness on dengue incidence in urban settings. Methods In this cluster-randomised controlled trial we enrolled low-cost and medium-cost residential housing blocks in the Federal Territory of Kuala Lumpur and Putrajaya with recurrent dengue outbreaks. Of the 329 eligible sites, 139 were randomly allocated to receive IVM measures (community engagement, targeted outdoor residual spraying using K-Othrine Polyzone , and deployment of autodissemination devices to target both larval and adult mosquitoes) and 141 received routine vector control activities, stratified by block housing cost. The primary outcome was the comparison of dengue incidence between the two groups using information provided by the national e-Dengue surveillance system. Routine vec...

Abstract {1} The 2023–24 epidemic of Oropouche fever in the Americas and the associated ongoing outbreak in Cuba suggests a potential state shift in the epidemiology of the disease , raising questions about which vectors are driving transmission. In this study, we conduct a systematic review of vector competence experiments with Oropouche virus (OROV, Orthobunyavirus ) that were published prior to the 2023–24 epidemic season. Only seven studies were published by September 2024, highlighting the chronic neglect that Oropouche virus (like many other orthobunyaviruses) has been subjected to since its discovery in 1954. Two species of midge (Culicoides paraensis and C. sonorensis) consistently demonstrate a high competence to transmit OROV (~30%), while mosquitoes (including both Aedes and Culex spp .) exhibited an infection rate consistently below ~20%, and showed limited OROV transmission . Further research is needed to establish which vectors are involved in the ongoing outbreak in Cub...

Abstract We describe introduction of the 2022–2023 Oropouche virus lineage from Brazil , which has caused large-scale outbreaks throughout Brazil , into the Amazon Region of Peru . This lineage is co-circulating with another lineage that was circulating previously. Our findings highlight the need for continued surveillance to monitor Oropouche virus in Peru. Source: US Centers for Disease Control and Prevention,  https://wwwnc.cdc.gov/eid/article/31/4/24-1748_article ____

Abstract Given recent outbreaks of Oropouche virus in Latin America and >100 confirmed travel-associated cases in the United States , we evaluated the competence of US vectors , including Aedes albopictus, Culex quinquefasciatus, Culex pipiens , and Anopheles quadrimaculatus mosquitoes . Results with historic and recent isolates suggest transmission potential for those species is low . Source: Emerging Infectious Diseases Journal,  https://wwwnc.cdc.gov/eid/article/31/3/24-1886_article _____