EVALUATING THERMAL LATENCY IN VECTOR-BORNE TRANSMISSION: A 60-MONTH TEMPORAL LAG AND PREDICTIVE REGRESSION ANALYSIS OF LAND SURFACE TEMPERATURE AND MALARIA INCIDENCE IN BAUCHI METROPOLIS, NIGERIA

Abstract

Abstract

Land surface thermal dynamics play a critical role in shaping vector-borne disease transmission in semi-arid environments. This study evaluated the temporal latency and predictive relationship between satellite-derived Land Surface Temperature (LST) and clinical malaria incidence in Bauchi Metropolis, Nigeria, across 60 consecutive months (2021–2025). Monthly LST metrics were extracted at 30-m resolution from MODIS thermal products. Clinical malaria cases were disaggregated using a Denton-Cholette procedure. Cross-correlation matrices were generated across temporal lags (0 to 2 months), and Ordinary Least Squares linear regression was fitted using the optimal lag predictor. Unlagged surface temperature (Lag 0) demonstrated a weak inverse correlation (r = - 0.155) with malaria cases, reflecting immediate thermal stress and breeding site desiccation. Conversely, a 2-month delayed exposure (Lag 2) shifted to a positive association (r = ＋0.183, p = 0.048), aligning with the biological timeframe required for vector development, sporogony, and human incubation. The regression model (Malaria Cases = 383.4  X LST_{Lag 2}  －3799.80;  R²= 0.0336) indicated that each 1 ℃elevation in 2-month lagged surface temperature yielded an estimated average increase of 383 clinical cases. Satellite-derived LST provides a reliable 60-day operational early warning window for proactive vector control in Sahelian urban settings.