Fig. 2From: Evaluation of onchocerciasis seroprevalence in Bioko Island (Equatorial Guinea) after years of disease control programmesOnchocerciasis seropositivity for age groups. Y axis, number of samples. Statistically significant differences were found between percentage of positivity in age groups by Chi-square test (χ 2 = 33.762, df = 4, P < 0.001). Note: There is a positive sample that was not included because the person's age was unknownBack to article page