If a pregnant mother is identified as being infected with syphilis, treatment can effectively prevent congenital syphilis from developing in the fetus, especially if he or she is treated before the sixteenth week of pregnancy. The fetus is at greatest risk of contracting syphilis when the mother is in the early stages of infection, but the disease can be passed at any point during pregnancy, even during delivery (if the child had not already contracted it). A woman in the secondary stage of syphilis decreases her fetus's risk of developing congenital syphilis by 98% if she receives treatment before the last month of pregnancy. An afflicted child can be treated using antibiotics much like an adult; however, any developmental symptoms are likely to be permanent.

Kassowitz’s law is an empirical observation used in context of congenital syphilis stating that the greater the duration between the infection of the mother and conception, the better is the outcome for the infant. Features of a better outcome include less chance of stillbirth and of developing congenital syphilis.

The Centers for Disease Control and Prevention recommends treating symptomatic or babies born to infected mother with unknown treatment status with procaine penicillin G, 50,000 U/kg dose IM a day in a single dose for 10 days. Treatment for these babies can vary on a case by case basis. Treatment cannot reverse any deformities, brain, or permanent tissue damage that has already occurred.

Congenital disease occurs due to the acquisition of the organism by a pregnant woman exposed to tissue cysts or oocytes in uncooked meat or substances contaminated with cat feces. Spontaneous abortion may result if the disease is acquired during the first trimester.

Congenital toxoplasmosis may lead to hydrocephalus, seizures, lymphadenopathy, hepatosplenomegaly, rash, and fever. However, retinochoroiditis is the most common manifestation, occurring in 3/4 of cases.

In congenital toxoplasmosis, the disease is bilateral in 65–85% of cases and involves the macula in 58%.

Chronic or recurrent maternal infection during pregnancy is not thought to confer a risk of congenital toxoplasmosis because maternal immunity protects against fetal transmission. In contrast, pregnant women without serologic evidence of prior exposure to Toxoplasma should take sanitary precautions when cleaning up after cats and avoid undercooked meats.

Death from congenital syphilis is usually due to bleeding into the lungs.

"Toxoplasma" infection can be prevented in large part by:

- cooking meat to a safe temperature (i.e., one sufficient to kill "Toxoplasma")

- peeling or thoroughly washing fruits and vegetables before eating

- cleaning cooking surfaces and utensils after they have contacted raw meat, poultry, seafood, or unwashed fruits or vegetables

- pregnant women avoiding changing cat litter or, if no one else is available to change the cat litter, using gloves, then washing hands thoroughly

- not feeding raw or undercooked meat to cats to prevent acquisition of "Toxoplasma"

Prolonged and intense rainfall periods are significantly associated with the reactivation of toxoplasmic retinochoroiditis. Changes promoted by this climatic condition concern both the parasite survival in the soil as well as a putative effect on the host immune response due to other comorbidities.

Developing countries are more severely affected by TORCH syndrome.

The formation of gummata is rare in developed countries, but common in areas that lack adequate medical treatment.

Syphilitic gummas are found in most but not all cases of tertiary syphilis, and can occur either singly or in groups. Gummatous lesions are usually associated with long-term syphilitic infection; however, such lesions can also be a symptom of benign late syphilis.

TORCH syndrome can be prevented by treating an infected pregnant person, thereby preventing the infection from affecting the fetus.

Meningeal syphilis (as known as syphilitic aseptic meningitis or meningeal neurosyphilis) is a chronic form of syphilis infection that affects the central nervous system. Treponema pallidum, which is a spirochate bacterium, is the main cause of syphilis, which spreads drastically throughout the body and can infect all the systems of the body if not treated appropriately. The bacterium is the main cause of the onset of meningeal syphilis and other treponemal diseases, and it consists of a cytoplasmic and outer membrane that can cause a diverse array of diseases in the central nervous system and brain.

Early symptomatic neurosyphillis (or acute syphilitic meningitis or neurorecurrence) is the onset of meningeal syphilis. The symptoms arise as a result of inflamed meninges, which eventually lead up to signs of meningitis.

"Treponema pallidum" invades the nervous system within three to eighteen months after the primary infection. The initial series of events is asymptomatic meningitis, which can remain in the human body system and produce more damage within the body. Every form of neurosyphilis has meningitis as a component; however, every case differs in severity. The individual is infected with syphilis through a gram negative bacteria that only humans can obtain. Syphilis has four stages of infection, which are primary, secondary, latent, and tertiary. If syphilis is not treated, the disease can affect various other systems in the body, including the brain, heart, and vessels. The infection of the heart and vessels leads to meningovascular syphilis, which is usually presented during the secondary stage of syphilis. If syphilis is prolonged, it can affect the nervous system, which is known as neurosyphilis. Meningeal syphilis is a component of neurosyphilis, which usually occurs in the tertiary stage of syphilis.

Congenital syphilis is that which is transmitted during pregnancy or during birth. Two-thirds of syphilitic infants are born without symptoms. Common symptoms that develop over the first couple of years of life include enlargement of the liver and spleen (70%), rash (70%), fever (40%), neurosyphilis (20%), and lung inflammation (20%). If untreated, late congenital syphilis may occur in 40%, including saddle nose deformation, Higoumenakis sign, saber shin, or Clutton's joints among others. Infection during pregnancy is also associated with miscarriage.

There are many different forms on prevention of syphilis and other sexually transmitted diseases in general. Prevention of syphilis includes avoiding contact of bodily fluids with an infected person. This can be particularly difficult because syphilis is usually transmitted by people who are unaware that they have the disease because they do not have any visible sores or rashes that may denote having an infection in general. Being abstinent or having mutually monogamous sex with a person who is uninfected with any type of sexually transmitted disease is the greatest guarantee of not becoming infected with syphilis or any form of a sexually transmitted disease. Using latex condoms can however reduce the risk of obtaining syphilis. In order to prevent further contamination to other individuals, benzathine penicillin is given to any contacts. Washing, douching, or urinating cannot prevent the transmission of a sexually transmitted disease in general.

Individuals obtain syphilis through a variety of circumstances. In general, syphilis can be transmitted from individual to individual through direct contact with sores that are present on the external genitals, vagina, rectum, anus, lips, or mouth. Transmission can occur through any form of sexual contact, including vaginal, anal, and oral sex. In addition, women who are pregnant and infected with syphilis can transmit the disease onto their child as well. If transmission has occurred, it is important to check up immediately with a physician to avoid further damage.

Congenital syphilis in the newborn can be prevented by screening mothers during early pregnancy and treating those who are infected. The United States Preventive Services Task Force (USPSTF) strongly recommends universal screening of all pregnant women, while the World Health Organization recommends all women be tested at their first antenatal visit and again in the third trimester. If they are positive, it is recommend their partners also be treated. Congenital syphilis is still common in the developing world, as many women do not receive antenatal care at all, and the antenatal care others receive does not include screening. It still occasionally occurs in the developed world, as those most likely to acquire syphilis (through drug use, etc.) are least likely to receive care during pregnancy. Several measures to increase access to testing appear effective at reducing rates of congenital syphilis in low- to middle-income countries. Point-of-care testing to detect syphilis appeared to be good although more research is needed to assess its effectiveness and into improving outcomes in mothers and babies.

In syphilis, the gumma is caused by reaction to spirochaete bacteria in the tissue.

It appears to be the human body's way to slow down the action of this bacteria, it is a unique immune response that develops in humans after the immune system fails to kill off syphilis.

Chancroid is a bacterial infection caused by the fastidious Gram-negative streptobacillus "Haemophilus ducreyi". It is a disease found primarily in developing countries, most prevalent in low socioeconomic groups, associated with commercial sex workers. In the United States socioeconomic status has not been found to be a factor in the spread of sexually transmitted diseases.

Chancroid, caused by H. ducreyi has infrequently been associated with cases of Genital Ulcer Disease in the US, but has been isolated in up to 10% of genital ulcers diagnosed from STD clinics in Memphis and Chicago.

Infection levels are very low in the Western world, typically around one case per two million of the population (Canada, France, Australia, UK and US). Most individuals diagnosed with chancroid have visited countries or areas where the disease is known to occur frequently, although outbreaks have been observed in association with crack cocaine use and prostitution.

Chancroid is a risk factor for contracting HIV, due to their ecological association or shared risk of exposure, and biologically facilitated transmission of one infection by the other.

Human immunodeficiency virus type I (HIV) infection can occur during labor and delivery, in utero through mother-to-child transmission or postnatally by way of breastfeeding. Transmission can occur during pregnancy, delivery or breastfeeding. Most transmission occurs during delivery. In women with low detectable levels of the virus, the incidence of transmission is lower. Transmission risk can be reduced by:

- providing antiretroviral therapy during pregnancy and immediately after birth

- delivery by caesarean section

- not breastfeeding

- antiretroviral prophylaxis in infants born to mothers with HIV.

A low number of women whose HIV status are unknown until after the birth, do not benefit from interventions that could help lower the risk of mother-to-child HIV transmission.

The duration of the visible blistering caused by varicella zoster virus varies in children usually from 4 to 7 days, and the appearance of new blisters begins to subside after the fifth day. Chickenpox infection is milder in young children, and symptomatic treatment, with sodium bicarbonate baths or antihistamine medication may ease itching. It is recommended to keep new infants from birth up to age 6 months away from an infected person for 10 to 21 days because their immune systems are not developed enough to handle the stress it can bring on. Paracetamol (acetaminophen) is widely used to reduce fever. Aspirin, or products containing aspirin, should not be given to children with chickenpox, as it can cause Reye's Syndrome.

In adults, the disease is more severe, though the incidence is much less common. Infection in adults is associated with greater morbidity and mortality due to pneumonia (either direct viral pneumonia or secondary bacterial pneumonia), bronchitis (either viral bronchitis or secondary bacterial bronchitis), hepatitis, and encephalitis. In particular, up to 10% of pregnant women with chickenpox develop pneumonia, the severity of which increases with onset later in gestation. In England and Wales, 75% of deaths due to chickenpox are in adults. Inflammation of the brain, or encephalitis, can occur in immunocompromised individuals, although the risk is higher with herpes zoster. Necrotizing fasciitis is also a rare complication.

Varicella can be lethal to adults with impaired immunity. The number of people in this high-risk group has increased, due to the HIV epidemic and the increased use of immunosuppressive therapies. Varicella is a particular problem in hospitals, when there are patients with immune systems weakened by drugs (e.g., high-dose steroids) or HIV.

Secondary bacterial infection of skin lesions, manifesting as impetigo, cellulitis, and erysipelas, is the most common complication in healthy children. Disseminated primary varicella infection usually seen in the immunocompromised may have high morbidity. Ninety percent of cases of varicella pneumonia occur in the adult population. Rarer complications of disseminated chickenpox include myocarditis, hepatitis, and glomerulonephritis.

Hemorrhagic complications are more common in the immunocompromised or immunosuppressed populations, although healthy children and adults have been affected. Five major clinical syndromes have been described: febrile purpura, malignant chickenpox with purpura, postinfectious purpura, purpura fulminans, and anaphylactoid purpura. These syndromes have variable courses, with febrile purpura being the most benign of the syndromes and having an uncomplicated outcome. In contrast, malignant chickenpox with purpura is a grave clinical condition that has a mortality rate of greater than 70%. The cause of these hemorrhagic chickenpox syndromes is not known.

Sixty percent of mothers of preterm infants are infected with cytomegalovirus (CMV). Infection is asymptomatic in most instances but 9% to 12% of postnatally infected low birth weight, preterm infants have severe, sepsis-like infection. CMV infection duration can be long and result in pneumonitis in association with fibrosis. CMV infection in infants has an unexpected effect on the white blood cells of the immune system causing them to prematurely age. This leads to a reduced immune response similar to that found in the elderly.

Late congenital syphilitic oculopathy is a disease of the eye, a manifestation of late congenital syphilis. It can appear as:

- Interstitial keratitis – this commonly appears between ages 6 and 12. Symptoms include lacrimation and photophobia. Pathological vascularization of the cornea cause it to turn pink or salmon colored. 90% of cases affect both eyes.

- Episcleritis or scleritis – nodules appear in or overlying the sclera (white of eye)

- Iritis or iris papules – vascular infiltration of the iris causes rosy color change and yellow/red nodules.

- Chorioretinitis, papillitis, retinal vasculitis – retinal changes can resemble retinitis pigmentosa.

- Exudative retinal detachment

Congenital syphilis is categorized by the age of the child. Early congenital syphilis occurs in children under 2 years old, and late congenital syphilis in children at or greater than 2 years old. Manifestations of late congenital syphilis are similar to those of secondary syphilis and tertiary syphilis in adults.

Chorioretinitis is often caused by toxoplasmosis and cytomegalovirus infections (mostly seen in immunodeficient subjects such as people with HIV or on immunosuppressant drugs). Congenital toxoplasmosis via transplacental transmission can also lead to sequelae such as chorioretinitis along with hydrocephalus and cerebral calcifications. Other possible causes of chorioretinitis are syphilis, sarcoidosis, tuberculosis, Behcet's disease, onchocerciasis, or West Nile virus. Chorioretinitis may also occur in presumed ocular histoplasmosis syndrome (POHS); despite its name, the relationship of POHS to "Histoplasma" is controversial.

Congenital toxoplasmosis is a specific form of toxoplasmosis in which an unborn fetus is infected via the placenta. Congenital toxoplasmosis is associated with fetal death and abortion, and in infants, it is associated with neurologic deficits, neurocognitive deficits, and chorioretinitis. A positive antibody titer indicates previous exposure and immunity, and largely ensures the unborn fetus' safety. A simple blood draw at the first prenatal doctor visit can determine whether or not a woman has had previous exposure and therefore whether or not she is at risk. If a woman receives her first exposure to "T. gondii" while pregnant, the fetus is at particular risk.

Not much evidence exists around the effect of education before pregnancy to prevent congenital toxoplasmosis. However educating parents before the baby is born has been suggested to be effective because it may improve food, personal and pet hygiene. More research is needed to find whether antenatal education can reduce congenital toxoplasmosis.

For pregnant women with negative antibody titers, indicating no previous exposure to "T. gondii", serology testing as frequent as monthly is advisable as treatment during pregnancy for those women exposed to "T. gondii" for the first time dramatically decreases the risk of passing the parasite to the fetus. Since a baby's immune system does not develop fully for the first year of life, and the resilient cysts that form throughout the body are very difficult to eradicate with antiprotozoans, an infection can be very serious in the young.

Despite these risks, pregnant women are not routinely screened for toxoplasmosis in most countries, for reasons of cost-effectiveness and the high number of false positives generated; Portugal, France, Austria, Uruguay, and Italy are notable exceptions, and some regional screening programmes operate in Germany, Switzerland and Belgium. As invasive prenatal testing incurs some risk to the fetus (18.5 pregnancy losses per toxoplasmosis case prevented), postnatal or neonatal screening is preferred. The exceptions are cases where fetal abnormalities are noted, and thus screening can be targeted.

Pregnant women should avoid handling raw meat, drinking raw milk (especially goat milk) and be advised to not eat raw or undercooked meat regardless of type. Because of the obvious relationship between "Toxoplasma" and cats it is also often advised to avoid exposure to cat feces, and refrain from gardening (cat feces are common in garden soil) or at least wear gloves when so engaged. Most cats are not actively shedding oocysts, since they get infected in the first six months of their life, when they shed oocysts for a short period of time (1–2 weeks.) However, these oocysts get buried in the soil, sporulate and remain infectious for periods ranging from several months to more than a year. Numerous studies have shown living in a household with a cat is not a significant risk factor for "T. gondii" infection, though living with several kittens has some significance.

In 2006, a Czech research team discovered women with high levels of toxoplasmosis antibodies were significantly more likely to have baby boys than baby girls. In most populations, the birth rate is around 51% boys, but women infected with "T. gondii" had up to a 72% chance of a boy. In mice, the sex ratio was higher in early latent toxoplasmosis and lower in later latent toxoplasmosis.

When a pregnant woman is diagnosed with acute toxoplasmosis, amniocentesis can be used to determine whether the fetus has been infected or not. When a pregnant woman develops acute toxoplasmosis, the tachyzoites have approximately a 30% chance of entering the placental tissue, and from there entering and infecting the fetus. As gestational age at the time of infection increases, the chance of fetal infection also increases.

If the parasite has not yet reached the fetus, spiramycin can help to prevent placental transmission. If the fetus has been infected, the pregnant woman can be treated with pyrimethamine and sulfadiazine, with folinic acid, after the first trimester. They are treated after the first trimester because pyrimethamine has an antifolate effect, and lack of folic acid can interfere with fetal brain formation and cause thrombocytopaenia. Infection in earlier gestational stages correlates with poorer fetal and neonatal outcomes, particularly when the infection is untreated.

Chorioretinitis is usually treated with a combination of corticosteroids and antibiotics. However, if there is an underlying cause such as HIV, specific therapy can be started as well.

A 2012 Cochrane Review found weak evidence suggesting that ivermectin could result in reduced chorioretinal lesions in patients with onchocercal eye disease. More research is needed to support this finding.

Uveitis may be an immune response to fight an infection inside the eye. While representing the minority of patients with uveitis, such possible infections include:

- brucellosis

- leptospirosis

- Lyme disease

- presumed ocular histoplasmosis syndrome

- syphilis

- toxocariasis

- toxoplasmic chorioretinitis

- tuberculosis

- Zika fever

"H. ducreyi" enters skin through microabrasions incurred during sexual intercourse. A local tissue reaction leads to development of erythomatous papule, which progresses to pustule in 4–7 days. It then undergoes central necrosis to ulcerate.

Granuloma inguinale (also known as donovanosis) is a bacterial disease caused by "Klebsiella granulomatis" (formerly known as "Calymmatobacterium granulomatis") characterized by ulcerative genital lesions. It is endemic in many less developed regions. It is also known as donovanosis, granuloma genitoinguinale, granuloma inguinale tropicum, granuloma venereum, granuloma venereum genitoinguinale, lupoid form of groin ulceration, serpiginous ulceration of the groin, ulcerating granuloma of the pudendum, and ulcerating sclerosing granuloma.

The disease often goes untreated because of the scarcity of medical treatment in the countries in which it is found. In addition, the painless genital ulcers can be mistaken for syphilis. The ulcers ultimately progress to destruction of internal and external tissue, with extensive leakage of mucus and blood from the highly vascular lesions. The destructive nature of donovanosis also increases the risk of superinfection by other pathogenic microbes.

Uveitis is usually an isolated illness, but can be associated with many other medical conditions.

In anterior uveitis, no associated condition or syndrome is found in approximately one-half of cases. However, anterior uveitis is often one of the syndromes associated with HLA-B27. Presence of this type of HLA allele has a relative risk of evolving this disease by approximately 15%.

The most common form of uveitis is acute anterior uveitis (AAU). It is most commonly associated with HLA-B27, which has important features: HLA-B27 AAU can be associated with ocular inflammation alone or in association with systemic disease. HLA-B27 AAU has characteristic clinical features including male preponderance, unilateral alternating acute onset, a non-granulomatous appearance, and frequent recurrences, whereas HLA-B27 negative AAU has an equivalent male to female onset, bilateral chronic course, and more frequent granulomatous appearance. Rheumatoid arthritis is not uncommon in Asian countries as a significant association of uveitis.