Navigation Links
Inherited virus can cause cognitive dysfunction and fatigue
Date:7/26/2013

Tampa, FL (July 25, 2013) -- Many experts believe that chronic fatigue syndrome (CFS) has several root causes including some viruses. Now, lead scientists Shara Pantry, Maria Medveczky and Peter Medveczky of the University of South Florida's Morsani College of Medicine, along with the help of several collaborating scientists and clinicians, have published an article in the Journal of Medical Virology suggesting that a common virus, Human Herpesvirus 6 (HHV-6), is the possible cause of some CFS cases.

Over 95 percent of the population is infected with HHV-6 by age 3, but in those with normal immune systems the virus remains inactive. HHV-6 causes fever and rash (or roseola) in infants during early childhood, and is spread by saliva. In immunocompromised patients, it can reactivate to cause neurological dysfunction, encephalitis, pneumonia and organ failure.

"The good news reported in our study is that antiviral drugs improve the severe neurological symptoms, including chronic pain and long-term fatigue, suffered by a certain group of patients with CFS," said Dr. Medveczky, who is a professor of molecular medicine at USF Health and the study's principal investigator. "An estimated 15,000 to 20,000 patients with this CFS-like disease in the United States alone may ultimately benefit from the application of this research including antiviral drug therapy."

The link between HHV-6 infection and CFS is quite complex. After the first encounter, or "primary infection," all nine known human herpesviruses become silent, or "latent," but may reactivate and cause diseases upon immunosuppression or during aging. A previous study from the Medveczky laboratory showed that HHV-6 is unique among human herpesviruses; during latency, its DNA integrates into the structures at the end of chromosomes known as telomeres.

Furthermore, this integrated HHV-6 genome can be inherited from parent to child, a condition commonly referred to as "chromosomally integrated HHV-6," or CIHHV-6. By contrast, the "latent" genome of all other human herpesviruses converts to a circular form in the nucleus of the cell, not integrated into the chromosomes, and not inheritable by future generations.

Most studies suggest that around 0.8 percent of the U.S. and U.K. population is CIHHV-6 positive, thus carrying a copy of HHV-6 in each cell. While most CIHHV-6 individuals appear healthy, they may be less able to defend themselves against other strains of HHV-6 that they might encounter. Medveczky reports that some of these individuals suffer from a CFS-like illness. In a cohort of CFS patients with serious neurological symptoms, the researchers found that the prevalence of CIHHV-6 was over 2 percent, or more than twice the level found in the general public. In light of this finding, the authors of the study suggest naming this sub-category of CFS "Inherited Human Herpesvirus 6 Syndrome," or IHS.

Medveczky's team discovered that untreated CIHHV-6 patients with CFS showed signs that the HHV-6 virus was actively replicating: determined by the presence of HHV-6 messenger RNA (mRNA), a substance produced only when the virus is active. The team followed these patients during treatment, and discovered that the HHV-6 mRNA disappeared by the sixth week of antiviral therapy with valganciclovir, a drug used to treat closely related cytomegalovirus (HHV-5). Of note, the group also found that short-term treatment regimens, even up to three weeks, had little or no impact on the HHV-6 mRNA level.

The investigators assumed that the integrated virus had become reactivated in these patients; however, to their surprise, they found that these IHS patients were infected by a second unrelated strain of HHV-6.

The USF-led study was supported by the HHV-6 Foundation and the National Institutes of Health.

Further studies are warranted to confirm that immune dysregulation, along with subsequent chronic persistence of the HHV-6 virus, is the root cause of the IHS patients' clinical symptoms, the researchers report.


'/>"/>

Contact: Anne DeLotto Baier
abaier@health.usf.edu
813-974-3303
University of South Florida (USF Health)
Source:Eurekalert

Related medicine news :

1. Inherited DNA change explains overactive leukemia gene
2. Mayo Clinic identifies promising treatment for inherited form of kidney disease
3. Cedars-Sinai physician-scientist awarded $3M to study most common inherited neurological disorder
4. Many Heart Defects Arent Inherited, Study Finds
5. Investigators trace of role reusable grocery bag in norovirus outbreak
6. 16th-century Korean mummy provides clue to hepatitis B virus genetic code
7. New study shows why swine flu virus develops drug resistance
8. Vygone Introduces A New Zapper For Effective Relief From Herpes Virus Related Skin Problems
9. Vygone Presents A New Product To Deal With Genital Warts And Other Herpes Virus Related Skin Problems
10. Moffitt researchers find cutaneous human papillomavirus infection a risk factor for skin cancer
11. Hepatitis C Virus Levels Higher in Certain Injection Drug Users
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... Viejo, California (PRWEB) , ... June 26, 2016 , ... ... Final Cut Pro X. , "Film editors can give their videos a whole new ... said Christina Austin - CEO of Pixel Film Studios. , ProSlice Levels contains ...
(Date:6/26/2016)... Clarkston, Michigan (PRWEB) , ... June 26, 2016 ... ... respect to fertility once they have been diagnosed with endometriosis. These women need ... but they also require a comprehensive approach that can help for preservation of ...
(Date:6/25/2016)... ... June 25, 2016 , ... The temporary closing of Bruton Memorial Library on June 21 due ... up a new, often overlooked aspect of head lice: the parasite’s ability to live away ... a common occurrence, but a necessary one in the event that lice have simply gotten ...
(Date:6/25/2016)... ... 25, 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned ... the David Geffen School of Medicine at UCLA. He trained in Internal Medicine at ... fellowship in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity ...
(Date:6/25/2016)... ... ... Conventional wisdom preaches the benefits of moderation, whether it’s a matter of ... too high can result in disappointment, perhaps even self-loathing. However, those who set the ... Research from PsychTests.com reveals that behind the tendency to set low expectations ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... Research and Markets has announced the ... report to their offering. ... favourable commercial environment for MedImmune to enter. The US ageing ... serve to drive considerable growth for effective anti-influenza medications. The ... sales considerably, but development is still in its infancy. ...
(Date:6/23/2016)... -- , , , WHEN: , ... , , , LOCATION: , , , Online, with free ... EXPERT PANELISTS:  , , , Frost & Sullivan,s Global Vice President ... Industry Analyst, Divyaa Ravishankar and Unmesh Lal, Program Manager , ... is witnessing an exceptional era. Several new demand spaces, such as ...
(Date:6/23/2016)... announced the establishment of Astellas Farma Colombia (AFC), a new affiliate with operations headquartered in Bogota. Colombia ... ... ... ... Astellas is a pharmaceutical ...
Breaking Medicine Technology: