Influence of daily mean temperature on incidence of hand foot and mouth disease in Jingzhou, Hubei, 2010–2017

ObjectiveTo discuss the 1ag effects of daily mean temperature on incidence of hand foot and mouth disease (HFMD) in Jingzhou of Hubei province.

MethodsThe data of daily cases of HFMD in Jingzhou from 2010 to 2017 were collected, and local meteorological data during the same period were collected too. Spearman correlation test was used to analyze the relationship between the meteorological factors and the daily case number of HFMD, and the distributed lag non-linear model was used to analyze the relationship between the daily mean temperature and the daily case number of HFMD. The temperature of 18.18 ℃ was used as reference for the estimation of RRs at different temperature (P₂₅, P₅₀, P₉₅). The delayed and cumulative effects of daily mean temperature on daily case number of HFMD were also assessed.

ResultsA total of 48 591 cases were reported in Jingzhou from 2010 to 2017. The daily mean case number of HFMD was related to daily average temperature, daily precipitation, daily average pressure, daily relative humidity and wind speed. An inverse U-shaped relationship was found consistently between daily mean temperature and the daily case number of HFMD, and the maximum value of effect at 18.19 ℃ was 2.67 (95% CI: 2.12–3.37). When the temperature was set to 9.76 ℃ (P₂₅), 18.35 ℃ (P₅₀) and 30.96 ℃ (P₉₅), the lag effect time of the significant positive influence (RR＞1.00) on daily case number of HFMD was 6–19 d, 6–21 d and 0 d respectively. The lag effect was highest on lag 0–21 d, and the RR values of HFMD was 1.11(95% CI: 1.04–1.19), 1.56(95% CI: 1.31–1.86), 2.67, (95% CI: 2.12–3.37), 1.58 (95% CI: 1.19–2.10) for 5.17 ℃(P₁₀), 9.76 ℃(P₂₅), 18.35 ℃(P₅₀) and 25.21 ℃(P₉₅) respectively.

ConclusionAverage temperature had significant influence on the risk of HFMD in Jingzhou. High temperature and low temperature could reduce the risk of HFMD, and the influence on the daily case number of HFMD was nonlinear and lagging.