Lower immunity to tetanus in cigarette smoker subjects

Cigarette smoking has been linked with the suppression of immune responses and increased susceptibility to numerous infections in humans. Tetanus is also a major public health problem in many countries. The aim of the present study was to evaluate the serum levels of anti-tetanus toxin antibodies in c igarette smoking and healthy non-smoking people. A total of 100 c igarette smokers and 100 age-matched healthy non-smoker individuals were enrolled in this descriptive study. A blood sample was collected from each participant. The samples were tested for the levels of anti-tetanus toxin antibodies b y use of enzyme linked immunosorbent assay. The seroprotective rate of anti-tetanus toxin antibodies in non-smoking group (99%) was significantly higher than that observed in c igarette smoking group (78%, P<0.0001). The mean titer of anti-tetanus toxin antibodies in non-smoking group (5.32± 0.26 IU/ml) was also significantly higher than that in smoker subjects (1.03 ± 0.16 IU/ml; P<0.0001). The mean titer of anti-tetanus toxin antibodies in individuals with smoking duration >10 years was significantly lower than that among smokers with smoking duration ≤10 years (0.59 ± 0.12 IU/ml vs 1.98 ± 0.41 IU/ml; P<0.001). The seroprotection rate was also significantly lower in persons with smoking duration >10 years in comparison to smokers with smoking duration ≤10 years (72.1% vs 90.6%; P=0.037). The mean titer of anti-tetanus toxin antibodies in individuals with daily smoking >10 cigarettes was also significantly lower in comparison to smokers with daily smoking ≤10 cigarettes (0.68 ± 0.15 IU/ml vs 1.63 ± 0.36 IU/ml; P<0.001). These results showed lower levels of anti-tetanus toxin antibodies in cigarette smokers which represents c igarette smoking as a risk factor for susceptibility to tetanus. A negative association was also observed between the immunity to tetanus and smoking burden.