Webster's New World Medical Dictionary

cervix, incompetent
A cervix that has an abnor-
mal tendency to dilate and so may not be able to
keep a fetus from being spontaneously aborted
(miscarried).
cesarean section
See 
caesarean section.
CFS
Chronic fatigue syndrome.
Chagas disease
An infectious disease found in
Central and South America caused by the parasite
Trypanosoma cruzi. The parasite can be transmitted
through bites from bugs that carry it (known as
kissing bugs) or via blood transfusion. Soon after
infection, there may be symptoms such as swelling
of the eye on one side of the face, usually at the bite
wound, but many people do not become ill until
many years after being infected. Infants and persons
with immunodeficiency are at risk of severe infec-
tions and complications such as meningitis and
heart failure. Also known as American trypanosomi-
asis. See also 
kissing bugs.
chalazion
See 
cyst, Meibomian.
CHAMPUS
Civilian Health and Medical Program
of the Uniformed Services. CHAMPUS is a US feder-
ally funded health program that provides benefici-
aries with medical care, supplemental to that
available in US military and Public Health Service
facilities. All CHAMPUS beneficiaries switch to using
Medicare at age 65. CHAMPUS is like Medicare in
that the government contracts with private parties to
administer the program. CHAMPUS was revamped
as a managed care system and renamed TRICARE.
chancre
The classic nonpainful ulcer of syphilis
that teems with spirochetes. A chancre forms in the
first (primary) stage of syphilis, is highly conta-
gious, and can last from 1 to 5 weeks. Syphilis can
be transmitted from any contact with a chancre. If a
chancre is outside the vagina or on the scrotum of
the male, the use of condoms may not help in pre-
venting transmission of syphilis. Likewise, if a chan-
cre is in the mouth, merely kissing an infected
individual can spread syphilis. See also 
syphilis.