Fig. 1From: Seroprevalence of IgG antibodies against diphtheria antitoxin among migrant workers in Singapore, 2016–2019Overall percentage of migrant workers with (A) at least basic protection against diphtheria (antitoxin titres ≥ 0.01 IU/ml) (B) full protection against diphtheria (antitoxin titres ≥ 0.10 IU/ml), by country of origin. The error bars indicate 95% confidence interval (CI)Back to article page