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AfriSUD: A Dependency Treebank Collection for Evaluating Models on African Languages

Despite their linguistic diversity and global significance, African languages remain underrepresented in research and resources to support NLP. We aim to bridge this gap by introducing AfriSUD, the first large-scale collection of syntactically annotated treebanks for nine diverse African languages spanning major language families and regions across Sub-Saharan Africa. Using the Surface-Syntactic Universal Dependencies (SUD) framework, our community-led effort provides high-quality, native-speaker verified data that capture typological key features such as agglutination and tone. We evaluate a range of models on AfriSUD for part-of-speech tagging and dependency parsing including non-transformer baselines, multilingual pretrained encoders, and LLMs. Our results reveal a significant syntax gap, where models still show clear limitations across the nine languages, suggesting that existing architectures may not fully capture the structural diversity of African-language syntax.

Projected epidemiologic and economic impact of the 7-1-7 outbreak response framework in Uganda: a stochastic modelling study of Bundibugyo Ebola virus

The 7 1 7 framework (detection 7 days, notification & 1 day, response & 7 days) is a global target for epidemic preparedness, but its prospective value during an active cross border outbreak has not been quantified. Using a stochastic SEIR model parameterised for Uganda with the Bundibugyo Ebola strain and three daily importation probabilities (10%, 30%, and the observed 56%), we compared a rapid 3 1 5 response (detection 3 days, notification 1 day, response 5 days) against a delayed counterfactual (detection 11 days, notification 10 days, response 12 days). The rapid response reduced median cumulative cases by 60 to 66% (26 to 31 cases vs. 76 to 80 cases) and deaths by 62 to 63% (3 deaths vs. 8 deaths) across all import levels, with total costs of USD 29.1 to 29.9 million compared to USD 37.4 to 38.1 million for the delayed scenario. The rapid response was strictly dominant (cost saving and life saving). Variance based Sobol sensitivity analysis identified the case fatality rate, import probability, and basic reproduction number as the most influential parameters, with detection and response delays contributing through interactions. Institutionalising the 7 1 7 framework in Uganda is projected to be highly cost effective and should be supported with sustainable domestic financing, community based surveillance at unofficial border points, three consecutive PCR laboratory capacity, and multilingual risk communication.

Network-based modelling of Bundibugyo Ebola virus disease importation and spread in Uganda using Displacement Tracking Matrix flow data and non-pharmaceutical intervention compliance scenarios

The 2026 Bundibugyo Ebola outbreak in Uganda, linked to the ongoing epidemic in the Democratic Republic of the Congo (DRC), spread through human mobility across borders and within the country. We constructed a data&driven directed weighted mobility network using IOM Displacement Tracking Matrix (DTM) flows collected from 15 to 24 May 2026 (11,245 observed movements) and the 2024 Uganda census (45.9 million people). A stochastic metapopulation SEIR model, incorporating pre symptomatic transmission and the movement of both exposed and infectious individuals, was simulated over 90 days across 135 Ugandan districts and two DRC provinces. The mobility network was sparse (density 0.11), highly unequal (Gini coefficient 0.67), and modular (modularity 0.5). Kisoro district had the highest import risk (in strength 3,823) and export risk (out strength 1,350), while Kampala showed substantial in strength (1,290) but lower out strength (150). Under baseline mobility, the model projected a median of 69 to 70 cumulative cases (95% CrI: 57 to 98) and 3 deaths over 90 days. Non pharmaceutical interventions (community contact reduction, healthcare protection, movement restriction) at 20%, 40%, and 60% compliance produced no statistically significant reduction in cases. Superspreading events occurred in 34.6 to 40.6% of simulations. Kampala bore the highest predicted burden (median 22 cases, 100% outbreak probability more than 10 cases), followed by Wakiso (11 cases, 64.9%). Border districts had lower burdens (Bundibugyo 5, Kasese 3, Kisoro 2). Sobol sensitivity analysis (500 samples, 200 bootstraps) identified the infectious period (first order index 0.838), case fatality rate (0.738), and basic reproduction number (0.664) as the most influential parameters; mobility and related parameters had lower total order indices. Given that mobility already saturates the transmission potential in the connected network, resources should focus on targeted surveillance at high&risk importation hubs (Kisoro for border screening) and inland epidemic centres (Kampala for response capacity), rather than un targeted nationwide interventions.