Symptoms, when they occur, are similar to
those of influenza and may include
- FEVER
- MUSCLEaches and JOINT PAIN
- upper respiratory congestion
- tiredness or fatigue
A BLOODtest that shows the presence of anti-
bodies confirms the diagnosis. Anyone who has
ever had toxoplasmosis will have a positive blood
test; infection confers lifelong IMMUNITY. Toxoplas-
mosis is self-limiting; once the illness runs its
course any symptoms subside. Though the T.
gondiiremain in the body, the IMMUNE SYSTEMcan
contain them so they do not cause illness. Doctors
may recommend treatment with sulfadoxine and
pyrimethamine, two medications used to prevent
MALARIA, for pregnant women who acquire T.
gondii infection or develop toxoplasmosis and for
people who are immunocompromised. These
medications are effective because T. gondiiis simi-
lar to the parasite that causes malaria. The antibi-
otic clindamycin is also effective in people who are
immunocompromised.
Washing the hands with warm water and soap
after handling cats, cleaning litter boxes, garden-
ing, and preparing pork or lamb removes T. gondii,
preventing infection. Pregnant women should also
wear gloves when gardening or cleaning litter
boxes.
See also ANTIBIOTIC MEDICATIONS; HAND WASHING;
INVESTIGATIONAL NEW DRUG(IND).
transmission modes The methods by which
pathogens spread to cause INFECTION. Common
transmission modes include
- airborne, in which pathogens enter the respira-
tory tract as particles suspended in the air - sexual, in which pathogens enter the body
through sexual contact - direct contact, in which pathogens enter the
body via touch - foodborne, in which consumed foods contain
pathogens - waterborne, in which consumed water and
foods prepared in that water contain pathogens- bloodborne, in which pathogens enter the
blood circulation through BLOOD TRANSFUSIONor
contaminated needles
- bloodborne, in which pathogens enter the
Many infectious agents have multiple transmis-
sion modes. The common cold, for example,
spreads through direct contact with nasal secre-
tions as well as via airborne droplets.
See also COLDS; FOODBORNE ILLNESSES; PATHOGEN;
SNEEZE/COUGH ETIQUETTE; WATERBORNE ILLNESSES.trichomoniasis A sexually transmitted disease
(STD) resulting from INFECTIONwith the protozoan
Trichomonas vaginalis. Though trichomoniasis
affects men and women equally, women are more
likely to show symptoms. About two thirds of
men and half of women who have trichomoniasis
do not have symptoms, though they are nonethe-
less able to spread the infection through sexual
contact.
Symptoms of trichomoniasis include- greenish or yellowish, often foul-smelling, dis-
charge - lower abdominal discomfort
- in men, burning with URINATION
- in women, vaginal or vulvar itching or burning
The diagnostic path includes examination
under the microscope of a sample of the discharge,
which usually contains T. vaginalisthough a third
of people who have the infection may have nega-
tive findings with this test. Culture of discharge
samples can provide definitive diagnosis. Treat-
ment is oral therapy with the medication metro-
nidazole. It is important to also treat all sexual
partners, as the likelihood that they also have the
infection is very high. Appropriate treatment cures
trichomoniasis, though infection may recur with
reexposure. Without treatment the infection
remains active. Complications of untreated tricho-
moniasis include EPIDIDYMITIS and PROSTATITIS in
men and chronic vaginitis and vaginal ulcerations
in women.
See also CANDIDIASIS; CHLAMYDIA; GENITAL HERPES;
GONORRHEA; HUMAN PAPILLOMAVIRUS (HPV); SEXUAL
HEALTH; SEXUALLY TRANSMITTED DISEASE(STD) PREVEN-
TION; SEXUALLY TRANSMITTED DISEASES(STDS); SYPHILIS;
URETHRITIS.358 Infectious Diseases