Immunology

Researchers at Wake Forest University Baptist Medical Center have disproved a long-standing clinical belief that the hepatitis C virus slows or stunts the immune system's ability to restore itself after HIV patients are treated with a combination of drugs known as the "cocktail." Hepatitis C (HCV) infection is more serious in HIV-infected people, leading to rapid liver damage, according to the Centers for Disease Control. Intravenous drug use is a main method of contraction for both HIV and HCV and 50 to 90 percent of HIV-infected drug users are also infected with HCV. The Wake Forest…

A genetic variation which evolved to protect people of African descent against malaria has now been shown to increase their susceptibility to HIV infection by up to 40 per cent, according to new research published today in Cell Host & Microbe. The work analyzed data from a 25-year study of thousands of Americans of different ethnic backgrounds. Conversely, the same variation also appears to prolong survival of those infected with HIV by approximately two years. The discovery marks the first genetic risk factor for HIV found only in people of African descent, and sheds light on the…

A new study of African lions says climate extremes, which would include the increased frequency of droughts and floods predicted by global warming models, can create conditions in which diseases that are tolerated individually might converge and cause mass extinction of livestock or wildlife. The study suggests that extreme climatic conditions are capable of altering normal host-pathogen relationships and causing a "perfect storm" of multiple infectious outbreaks that could trigger epidemics with catastrophic mortality. Led by scientists at the University of California, Davis, the University…

Leprosy, attributable to infection with Mycobacterium leprae, was once endemic over much of the world. Though now often considered a “tropical disease,” cases occurred north of the Arctic Circle just 100 years ago. The disease has gradually disappeared from higher latitudes in recent centuries. The last case of leprosy attributable to continued transmission in the British Isles had onset around 1800 (1) and in Norway the last case had onset around 1950 (2). Mycobacterium leprae was carried repeatedly across the Atlantic from both Europe and Africa in the last few hundred years, becoming…

By disrupting the potassium channel of the malaria parasite, a team of researchers has been able to prevent new malaria parasites from forming in mosquitoes and has thereby broken the cycle of infection during recent animal tests. By genetically altering the malaria parasite through gene knock-out technol-ogy, a research team consisting of scientists at the University of Copenha-gen and John Hopkins University, Baltimore, has prevented the parasite from going through the normal stages of its life cycle and developing a cyst (egg-like structure or occyst), which spawns new infectious…

Researchers have demonstrated the possibility of preventing the human malaria parasite, Plasmodium falciparum, which is responsible for more than a million malaria deaths a year, from becoming sexually mature. The discovery could have implications for controlling the spread of drug resistance, which is a major public health problem and which hinders the control of malaria. The life cycle of Plasmodium falciparum is complex, and it is not yet known what triggers the production of parasite gametes or sex cells. These sexual forms of the parasite do not contribute to malaria symptoms, but are…

Alzheimer’s disease (AD), the most frequent cause of dementia, is a form of amyloidosis. It has been known for a century that dementia, brain atrophy and amyloidosis can be caused by chronic bacterial infections, namely by Treponema pallidum in the atrophic form of general paresis in syphilis. Bacteria and viruses are powerful stimulators of inflammation. It was suggested by Alois Alzheimer and his colleagues a century ago that microorganisms may be contributors in the generation of senile plaques in AD. A number of chronic diseases are in fact caused by one or more infectious agents -…

A new study reveals the genetic identity of human immunodeficiency virus (HIV), the version responsible for sexual transmission, in unprecedented detail. The finding provides important clues in the ongoing search for an effective HIV/AIDS vaccine, said researchers at the University of Alabama at Birmingham (UAB). The UAB team found that among billions of HIV variants only a few lead to sexual transmission. Earlier studies have shown that a ‘bottleneck’ effect occurs where few versions of the virus lead to infection while many variants are present in the blood. The UAB study is the first to…

On the 25th anniversary of the first scientific article linking a retrovirus to AIDS, Anthony S. Fauci, M.D., director of the National Institute of Allergy and Infectious Diseases, reflects on his experience treating and studying HIV/AIDS for the past quarter century. Outlining the peaks and valleys of the scientific community’s journey so far, Dr. Fauci writes, “…we must learn from our mis-steps, build on our successes in treatment and prevention, and renew our commitment to developing the truly transforming tools that will one day put this scourge behind us.” From the outset, AIDS was…

Red colobus monkeys in a park in western Uganda have been exposed to an unknown orthopoxvirus, a pathogen related to the viruses that cause smallpox, monkeypox and cowpox. Most of the monkeys screened harbor antibodies to a virus that is similar – but not identical – to known orthopoxviruses. The study was begun in 2006 when Colin Chapman, a researcher at McGill University, invited Goldberg to collaborate on a health assessment of two groups of red colobus monkeys in Kibale National Park, in western Uganda. Chapman, also an associate scientist with the Wildlife Conservation Society, had…