Human cytomegalovirus (HCMV) has been definitely implicated in certain human diseases. Additionally, there have been suggestions based on limited and not always consistent findings of a role of HCMV in numerous additional illnesses. These somewhat questionable findings are readily explainable by the existence of atypically structured cytomegaloviruses, some of which are actually of monkey origin. Such atypical viruses have been grouped under the terms stealth and stealth-adapted, referring to the lack of the few critical viral components targeted by the cellular immune system. Stealth viruses lacking these components can, nevertheless, induce cellular damage generally without an accompanying inflammatory response. ;
Congenital HCMV infection is the most common known cause of mental retardation. It has also been linked to some cases of autism. Newborns are thought to be prone to HCMV because of the absence/immaturity of an effective immune system. They can acquire infection through their mother's milk. Infections acquired shortly after birth have the potential of causing minimal brain damage. Even with an intact immune system, children and adults can develop a mononucleosis-type syndrome with signs of liver damage, enlarged lymph nodes and fatigue. More intense gastrointestinal diseases affecting the esophagus, stomach, small intestine (enteropathy) and/or large intestine (colitis) have been reported in immunocompetent CMV infected individuals. These diseases are far m ore common and severe in patients with impaired cellular immunity resulting from chemotherapy, radiation therapy and especially from HIV infection. Encephalitis, myelitis, retinitis, uveitis, myocarditis, hepatitis, anemia and thrombocytopenia, periodontal and apical dental diseases, and other illnesses have been ascribed to HCMV infections in immunocompromised individuals.
Suggestive evidence for an involvement of HCMV has also been provided for the following diseases: Atherosclerosis, Alzheimer's disease, schizophrenia, depression, type I and type II diabetes, thyroid, adrenal and pituitary dysfunctions, Wegener's granulmatosis, scleroderma, primary biliary cirrhosis, deafness and vitiligo. HCMV has been associated with several types of malignancies, most convincingly for salivary gland tumors, but also breast and prostate tumors.
What then of the potential illnesses associated with stealth-adapted cytomegaloviruses. At least they must include all of the above. Stealth viruses have also been shown to pass readily between species, a feature that is generally not seen with cytomegaloviruses of either human or animal origins. The list of illnesses potentially caused by stealth-adapted viruses therefore extends to animal diseases. The prototype stealth virus has acquired genetic sequences from bacteria suggesting they may readily pass through bacteria. They can also acquire cellular genes, including genes with potential cancer causing activity.
The Public Health response to learning of the existence of stealth adapted viruses has been more protective of its major institutions than of the public. Hopefully, there will be an intense catch up effort and mankind will not succumb to the indifference and neglect displayed by those who have been in authority. One can only hope.
