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.

"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 majority of cases (85%) occur during birth when the baby comes in contact with infected genital secretions in the birth canal, most common with mothers that have newly been exposed to the virus (mothers that had the virus before pregnancy have a lower risk of transmission), an estimated 5% are infected in utero, and approximately 10% of cases are acquired postnatally. Detection and prevention is difficult because transmission is asymptomatic in 60% - 98% of cases.

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

Among the maternal risk factors for Neonatal HSV-1: White non-Hispanic race, young maternal age (<25), primary infection in third trimester

, first pregnancy, HSV (1&2) seronegative, discordant partner, gestation <38 weeks, receptive oral sex in third trimester.

Neonatal HSV-2 maternal risk factors: Black race, young maternal age (<21), discordant partner, primary or non primary first episode infection in third trimester, four or more lifetime sexual partners, lower level of education, history of previous STD, history of pregnancy wastage, first viable pregnancy, gestation <38 weeks.

Individuals with a weak immune system are most at risk. This includes individuals taking immunosuppressive medication, cancer patients, HIV patients, premature babies with very low birth weight, the elderly, etc.

People who are at an increased risk of acquiring particular fungal infections in general may also be at an increased risk of developing fungal meningitis, as the infection may in some cases spread to the CNS. People residing in the Midwestern United States, and Southwestern United States and Mexico are at an increased risk of infection with "Histoplasma" and "Coccidioides", respectively.

Progressive disseminated histoplasmosis is an infection caused by Histoplasma capsulatum, and most people who develop this severe form of histoplasmosis are immunocompromised or taking systemic corticosteroids. Skin lesions are present in approximately 6% of patients with dissemination.

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.

Prognosis depends on the pathogen responsible for the infection and risk group. Overall mortality for "Candida" meningitis is 10-20%, 31% for patients with HIV, and 11% in neurosurgical cases (when treated). Prognosis for "Aspergillus" and coccidioidal infections is poor.

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.

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.

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 prognosis of nocardiosis is highly variable. The state of the host's health, site, duration, and severity of the infection all play parts in determining the prognosis. As of now, skin and soft tissue infections have a 100% cure rate, and pleuropulmonary infections have a 90% cure rate with appropriate therapy. The cure rate falls to 63% with those infected with dissemented nocardiosis, with only half of those surviving infections that cause brain abscess. Additionally, 44% of people who are infected in the spinal cord/brain die, increasing to 85% if that person has an already weakened immune system. Unfortunately, there is not a preventative to nocardiosis. The only recommendation is to protect open wounds to limit access.

Normally found in soil, these organisms cause occasional sporadic disease in humans and animals throughout the world. Another well publicized find is that of Nocardia as an oral microflora. Nocardia spp. have been reported in the normal gingiva and periodontal pockets along with other species such as "Actinomyces", "Arthromyces" and "Streptomyces" spp.

The usual mode of transmission is inhalation of organisms suspended in dust. Another very common method is that by traumatic introduction, especially in the jaw. This leads to the entrance of Nocardia into the blood stream and the propagation of its pathogenic effects. Transmission by direct inoculation through puncture wounds or abrasions is less common. Generally, nocardial infection requires some degree of immune suppression.

A weakened immune system is a general indicator of someone who is more susceptible to nocardiosis, such as someone who already has a disease that weakens their immune system. Additionally, those with low T-cell counts or other complications involving T-cells can expect to have a higher chance of becoming infected. Besides those with weak immune systems, a local traumatic inoculation can cause nocardiosis, specifically the cutaneous, lymphocutaneous, and subcutaneous forms of the disease.

In contrast to visceral larva migrans, ocular toxocariasis usually develops in older children or young adults with no history of pica. These patients seldom have eosinophilia or visceral manifestations.

Purpura fulminans is rare and most commonly occurs in babies and small children but can also be a rare manifestation in adults when it is associated with severe infections. For example, Meningococcal septicaemia is complicated by purpura fulminans in 10–20% of cases among children. Purpura fulminans associated with congenital (inherited) protein C deficiency occurs in 1:500,000–1,000,000 live births.

It can be treated with systemic antiviral drugs, such as aciclovir or valganciclovir. Foscarnet may also be used for immunocompromised host with Herpes simplex and acyclovir-resistant Herpes simplex.

The eye involvement can cause the following inflammatory disorders:

- endophthalmitis

- uveitis

- chorioretinitis

Eczema herpeticum is a rare but severe disseminated infection that generally occurs at sites of skin damage produced by, for example, atopic dermatitis, burns, long term usage of topical steroids or eczema. It is also known as Kaposi varicelliform eruption, Pustulosis varioliformis acute and Kaposi-Juliusberg dermatitis.

Some sources reserve the term "eczema herpeticum" when the cause is due to human herpes simplex virus, and the term "Kaposi varicelliform eruption" to describe the general presentation without specifying the virus.

This condition is most commonly caused by herpes simplex virus type 1 or 2, but may also be caused by coxsackievirus A16, or vaccinia virus. It appears as numerous umbilicated vesicles superimposed on healing atopic dermatitis. it is often accompanied by fever and lymphadenopathy. Eczema herpeticum can be life-threatening in babies.

Mendelian susceptibility to mycobacterial disease, also called familial disseminated atypical mycobacterial infection, is a rare genetic disease characterized by susceptibility to mycobacteria and Salmonella infection outside of the intestinal tract.

It is not practical to test or decontaminate most sites that may be contaminated with "H. capsulatum", but the following sources list environments where histoplasmosis is common, and precautions to reduce a person's risk of exposure, in the three parts of the world where the disease is prevalent. Precautions common to all geographical locations would be to avoid accumulations of bird or bat droppings.

The US National Institute for Occupational Safety and Health (NIOSH) provides information on work practices and personal protective equipment that may reduce the risk of infection. This document is available in English and Spanish.

Authors at the University of Nigeria have published a review which includes information on locations in which histoplasmosis has been found in Africa (in chicken runs, bats and the caves bats infest, and in soil), and a thorough reference list including English, French, and Spanish language references.

Disseminated disease refers to a diffuse disease-process, generally either infectious or neoplastic. The term may sometimes also characterize connective tissue disease.

A disseminated infection, for example, has extended beyond its origin or nidus and involved the bloodstream to "seed" other areas of the body. Similarly, one can view metastatic cancer as a disseminated infection in that it has extended into the bloodstream or into the lymphatic system and thus "seeded" distant sites (a process known as metastasis).

Disseminated disease often contrasts localized disease.

This is a partial list of human eye diseases and disorders.

The World Health Organization publishes a classification of known diseases and injuries, the International Statistical Classification of Diseases and Related Health Problems, or ICD-10. This list uses that classification.

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