Relative transmissibility of shigellosis among male and female individuals: a modeling study in Hubei Province, China

Background Developing countries exhibit a high disease burden from shigellosis. Owing to the different incidences in males and females, this study aims to analyze the features involved in the transmission of shigellosis among male (subscript m ) and female (subscript f ) individuals using a newly developed sex-based model. Methods The data of reported shigellosis cases were collected from the China Information System for Disease Control and Prevention in Hubei Province from 2005 to 2017. A sex-based Susceptible–Exposed–Infectious/Asymptomatic–Recovered (SEIAR) model was applied to explore the dataset, and a sex-age-based SEIAR model was applied in 2010 to explore the sex- and age-specific transmissions. Results From 2005 to 2017, 130 770 shigellosis cases (including 73 981 male and 56 789 female cases) were reported in Hubei Province. The SEIAR model exhibited a significant fitting effect with the shigellosis data ( P <  0.001). The median values of the shigellosis transmission were 2.3225 × 10 8 for SAR mm (secondary attack rate from male to male), 2.5729 × 10 8 for SAR mf , 2.7630 × 10 -8 for SAR fm , and 2.1061 × 10 -8 for SAR ff . The top five mean values of the transmission relative rate in 2010 (where the subscript 1 was defined as male and age ≤ 5 years, 2 was male and age 6 to 59 years, 3 was male and age ≥ 60 years, 4 was female and age ≤ 5 years, 5 was female and age 6 to 59 years, and 6 was male and age ≥ 60 years) were 5.76 × 10 -8 for β 61 , 5.32 × 10 -8 for β 31 , 4.01 × 10 -8 for β 34 , 7.52 × 10 -9 for β 62 , and 6.04 × 10 -9 for β 64 . Conclusions The transmissibility of shigellosis differed among male and female individuals. The transmissibility between the genders was higher than that within the genders, particularly female-to-male transmission. The most important route in children (age ≤ 5 years) was transmission from the elderly (age ≥ 60 years). Therefore, the greatest interventions should be applied in females and the elderly.