Crabs

Hi Doctor,
    I recently noticed that my pubic region was itching me, so I went on the internet to see what could be some causes.  Most of the sites talked about crabs.  Since I have been without sex for about 2 years (due to my paranoia about STD's), I didnt look in that direction.  I then saw some pictures of pubic lice and checked myself out.  To my shock I found pubic lice. Some of the websites stated you could get crabs from wearing others clothes, close contact, but mostly from sexual contact.  I have not had sex in 2 years, and have not wore anybody elses clothes or have had that type of close contact.  One website (New York Health Dept site) stated dogs can carry pubic lice and pass it to humans.  Most other websites stated this was not possible.  I work in the Veterinary field and deal with animals who are neglected and come in with fleas, ticks, scabies and other ecto and endoparasites.  Could I have contracted pubic lice from a dog, and if not, how else could I have come in contact with it.   Any answers would be most appreciative.  Thanks for your time

[H. Hunter Handsfield, M.D.]

My understanding is that Phthirus pubis--the crab louse--is a strictly human parasite, and certainly I am not aware of any animal lice that ever infect humans.  I am unaware of a dog connection, but the NYC health department is a respected institution.  Perhaps that information is accurate, but I cannot vouch for it.  Generally lice are very species-specific , except the common body louse likes both humans and rats (hence the historic association of lice with plague and typhus epidemics).

Pubic lice can be transmitted sexually, but need not be.  Many cases, like yours, are acquired by sharing intimate clothing or sleeping in contaminated beds.

Pubic lice are an unpleasant inconvenience, not an important health risk.  Normally it is recommended that people with crabs get tested for other common STDs, but that's not necessary in your case, if it is true you haven't been sexually active for two years.

Good luck--  HHH, MD