Sexually Transmitted Diseases

[Concerned Dad]

My son's wife contracted trichomoniasis. When he got tested, he was negative. She contends that she must have had it since before they were married, but has had no symptoms until just now. They have been married for nearly 2 years. Symptoms usually appear in women within 5 to 28 days of exposure. I believe that her being without symptoms for this long is possible, but unlikely. Also I believe that, if she has had the disease for as long as she says, my son would also be infected.

My conclusion: she has had unprotected sex with someone other than my son within the last month.

Question to any physicians: What are the chances of her being infected this long without infecting my son?