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1.The diseases may be more likely to produce symptoms in one sex than the other but it remains contagious. For example, a man may readily see a primary chancre of syphilis on his glans whilst a woman is unaware of one on her cervix. Candida may cause vaginal discharge and pruritus vulvae but often in men it causes no symptoms.
2.some STDS take a long period before they show there symptoms
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