Oumayma Arbani

Background: Highly pathogenic avian influenza (HPAI) poses a critical global threat to both the poultry industry and public health. Although Morocco currently maintains HPAI-free status, the country faces substantial risk due to its location along major migratory flyways and its extensive commercial trade networks within the poultry sector. Available data indicate that the links between live bird markets, production farms, and related facilities in the poultry sector constitute a pivotal determinant of disease epidemiology. This study aimed to analyze these movements and determine how they can influence the spread of the disease and to guide policymakers in developing effective risk-based surveillance and control strategies tailored to the local context.: A questionnaire-based cross-sectional survey was conducted across the Casablanca-Settat region, including nine provinces and 138 municipalities, to investigate the movement patterns within the poultry sector in this region. Social network analysis (SNA) was employed to construct a movement network, and findings were spatially visualized using Geographic Information Systems (GIS) and analyzed through network analysis in R.: A total of 945 transport routes were recorded in 126 municipalities. Centrality measures identified three predominant network nodes exhibiting high degree and betweenness centrality values. Our findings indicate that although the network has a low density, the transmission of IAHP remains critical due to frequent bidirectional links and a heterogeneous network structure. The high concentration of movements by a few “hub” municipalities leads to an early emergence and rapid dissemination.: The identification of highly influential nodes allows veterinary authorities to prioritize and target surveillance activities toward municipalities with the greatest likelihood of disease introduction or persistence. The network’s structural connectivity suggests a theoretical potential for rapid HPAI spread, underscoring the importance of the frequent bidirectional links identified between municipalities. This protects both Morocco’s poultry industry and public health.

Background and Aim: Highly pathogenic avian influenza (HPAI) remains a global threat to poultry production, trade, and public health. While Morocco has not yet reported confirmed HPAI outbreaks, the endemic circulation of low-pathogenic avian influenza (LPAI) H9N2 since 2016, proximity to affected neighboring countries, and Morocco’s position along migratory bird flyways highlight the country’s vulnerability. This study aimed to identify high-risk areas for HPAI introduction and spread to inform risk-based surveillance and control policies. Materials and Methods: We applied a spatial multi-criteria decision analysis integrated with geographic information systems at the provincial scale. Relevant risk factors were identified through a literature review and expert consultation, and categorized into the introduction (wetlands, live poultry imports, recreational bird imports, and poultry products) and spread (poultry density and type, live bird markets, transport networks, and human population density) domains. Weights were assigned to factors using the analytic hierarchy process based on responses from 73 poultry-sector experts. Data were normalized, integrated into composite risk maps, and validated against historical LPAI H9N2 outbreak data (2016). Sensitivity and uncertainty analyses were used to assess model robustness. Results: The final maps revealed that 25 provinces (33.3% of the national territory) exhibited high-to-very high risk of HPAI introduction, particularly along northern coastal provinces, border regions, and areas linked to recreational bird imports. For spread risk, 41 provinces (41.3%) were classified as high to very high, concentrated in the Casablanca–Settat, Rabat–Salé–Kenitra, Fès–Meknès, and Marrakech–Safi regions, which are characterized by dense poultry production, major trade hubs, and extensive transport networks. Sensitivity analyses confirmed the model's stability, with variations in weight producing a minimal impact on risk classifications. Conclusion: This study provides the first comprehensive spatial risk maps of HPAI introduction and spread in Morocco, highlighting priority provinces for early detection, targeted surveillance, and preventive biosecurity measures. Despite limitations arising from reliance on LPAI data and expert judgment, the approach offers a robust decision-support tool for veterinary authorities. The methodology is adaptable to regional applications and can be refined with real-time surveillance data, enhancing Morocco’s preparedness and resilience against future avian influenza incursions. Keywords: avian influenza, biosecurity, geographic information system, Morocco, multi-criteria decision analysis, risk mapping, surveillance.

Since 2016, low pathogenic avian influenza virus (LPAIV) H9N2 became a major issue for poultry production in Morocco. Even though the agent was classified as low pathogenic, AI H9N2 cause significant economic losses, particularly during co-infections. Experimentally, it has been difficult to reproduce the clinical picture without appealing other viral or bacterial pathogens. Our study was carried out to evaluate a new challenge model using cold stress in commercial broilers infected with two Moroccan H9N2 viruses isolated in 2016 and 2022. One hundred twenty day-old chicks were divided into four groups: A, B, and C exposed to cold stress, and D was kept as negative control. At 21 days of age, Groups A and B were challenged by oculo-nasal route with 10⁷ EID₅₀ of H9N2 strains, isolated respectively during 2016 and 2022. Meanwhile, chicks of group C were exposed to only cold stress. The assessment of body weight gain, clinical signs, lesions, mortality, and oropharyngeal viral shedding was monitored for 15 days post-challenge. Results showed that cold stress exacerbated H9N2 clinical signs, allowing us to establish a scoring system and to validate the challenge model without co-infections. Gross and microscopic lesions, induced by the virus primarily in the respiratory tract, peaked at 5 dpi and significantly decreased at 15 dpi. Group B harbored the highest viral loads with viral shedding persisting beyond 11 dpi in both groups. This study demonstrates a clear clinical difference among the two isolates; A/chicken/Morocco/178-2/2022(H9N2) showed a significant increase in virulence compared to the firstly isolate A/chicken/Morocco/SF1/2016(H9N2). The novel H9N2 challenge model using cold stress will contribute to a better understanding of LPAI pathogenesis and epidemiology and allow for research closer to the field.

Backyard poultry farming is an important tool for poverty alleviation and food security in rural areas of Morocco. A descriptive epidemiologic survey was conducted in 286 backyard poultry flocks from the provinces of Khemisset and Skhirat-Temara to gain baseline data on the current status of backyard poultry flocks in Morocco as well as its potential implications on the transmission and spread of avian diseases. The findings indicated that 88.8% of flocks were raised in a mixed confinement system, with an average flock size of 30 birds (range 1–352). Chickens accounted for 83% of the overall reported birds. More than two-thirds of respondents (69%) kept chickens only, while the remaining flocks raising multiple bird species in total promiscuity. Diseases were the highest cause of mortality (84.7%), followed by predation (15.3%). According to 56.1% of the owners, respiratory symptoms were among the major disease signs reported, besides ectoparasite infestation. Flock health management revealed a lack of preventive vaccination, lack of veterinary consulting, lack of biosecurity practices, and irrational self-medication of diseased birds using antibiotics, pesticides, and hazardous chemicals that could be a significant health risk for consumers. The need for an outreach program about disease prevention and biosecurity practices, along with prophylactic campaigns, should be emphasized to further mitigate the risks of backyard poultry flocks on the commercial sector and public health.