Transmission

Male circumcision reduces risk of HIV transmission from women to men

The first study to examine the probability ofHIV infection per act of heterosexual sex among a population withmultiple sexual partners has found that uncircumcised men have morethan twice the risk of acquiring HIV than do circumcised men.In the study, published in the Feb. 15 issue of The Journal ofInfectious Diseases, now available online, Jared Baeten and colleaguesfrom the United States...

New studies suggest airborne SARS transmission is possible

Two new studies present evidence that the virus causing severe acute respiratory syndrome (SARS) may spread through the air, not just through direct contact with contaminated water droplets as previous research had shown. SARS coronavirus was detected in the air in a patient's room during the 2003 outbreak in Toronto, according to a new study published in The Journal of Infectious Diseases...

Reducing malarial transmission in Africa

There are 300 million cases of malaria each year worldwide, causing one million deaths. Around 90% of these deaths occur in Africa, mostly in young children. One of the greatest challenges facing Africa in the fight against malaria is drug resistance; resistance to chloroquine (CQ), the cheapest and most widely used antimalarial, is common throughout Africa, and resistance to sulfadoxine-pyrimeth...

HIV-1 spread through six transmission lines in the UK

Contrary to the prevailing belief that the HIV epidemic in the UK can be traced back to one source, a new study suggests that HIV spread via at least six independent virus introductions and subsequent transmission chains. The findings, published in the latest issue of the Proceedings of the National Academy of Sciences, also suggest that antiviral therapy has not had a significant impact on the g...

Aircraft Cabin Ventilation Influences The Transmission Of Diseases In-flight

Increasing ventilation within aircraft cabins can reduce the spread of infectious diseases in-flight, suggests a review published in this week's issue of THE LANCET. Mark Gendreau (Lahey Clinic Medical Centre, MA, USA) and colleagues reviewed data from studies looking at the transmission of diseases during commercial air travel. They found that while commercial airlines are a suitable envi...

Antiretroviral Therapy May Prevent HIV Transmission From Breastfeeding Mothers To Infants

Two new studies support the hypothesis that combination antiretroviral drug therapy may reduce the risk of mother-to-child HIV transmission through breastfeeding, findings that could have significant implications in the developing world. Researchers in the first study found mothers pass antiretroviral medications on to their breastfeeding infants in concentrations high enough to prevent in...

Studies clarify risk factors for mother-to-child transmission of hepatitis C virus

Breastfeeding does not raise the risk of mother-to-child transmission of hepatitis C virus (HCV), according to two new studies published in the December 1 issue of The Journal of Infectious Diseases, now available online. One study found that infant girls are twice as likely to be infected as infant boys. Both studies provide new information with which to counsel pregnant women infected...

Study uncovers placental microtransfusions lead to transmission of AIDS virus during childbirth

Transmission of HIV, the virus that causes AIDS, from pregnant women to their infants sometime during childbirth is a huge international problem, studies have shown. Between 25 percent and 35 percent of babies born to untreated HIV-infected mothers become infected themselves. That's a half million newborn worldwide every year facing chronic illness and premature death on their first day ou...

Lateral thinking produces first map of gene transmission

A University of Queensland study mapping the evolution of genes has shed light on the role of gene transfer in bacterial diseases. Dr Robert Beiko, Professor Mark Ragan and Mr Timothy Harlow examined the genomes of 144...

Anti-HIV drug has potential to prevent transmission in women

A new study from infectious disease researchers at The Miriam Hospital and Brown Medical School finds that a drug already given orally to treat HIV is also safe when applied as a vaginal microbicide gel. Microbicides are designed to prevent the sexual transmission of HIV and other sexually transmitted diseases and may be formulated as vaginal gels, foams, creams, or suppositories. "The re...

Avian flu transmission to humans may be higher than thought

A new study suggests that there is an association between direct contact with dead or sick poultry and flu-like illness in humans and that the transmission is probably more common than expected, according to a new study in the January 9 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. Anna Thorson, M.D., Ph.D., from the Karolinska Institutet, Stockholm, Sweden, an...

Ritalin packs punch by elevating norepinephrine, suppressing nerve signal transmissions

Methylphenidate (Ritalin) elevates norepinephrine levels in the brains of rats to help focus attention while suppressing nerve signal transmissions in the sensory pathways to make it easier to block out extraneous stimuli, a Philadelphia research team has found. Their report in the Journal of Neurophysiology helps explain how a stimulant aids people with attention deficit and hyperactivity...

Cultural transmission in bats: When listening for dinner, bats learn from their neighbors

In an exciting study that provides new understanding of how animals learn--and learn from each other--researchers have demonstrated that bats that use frog acoustic cues to find quality prey can rapidly learn these cues by observing other bats. While numerous examples are known of instances where predators can use so-called "social learning" to learn new visual and olfactory cues associated with...

Defense peptide found in primates may block some human HIV transmissions

As primates evolved 7 million years ago, the more advanced species stopped making a protein that University of Central Florida researchers believe can effectively block the HIV-1 virus from entering and infecting blood cells. HIV-1 often mutates quickly to overcome antiviral compounds designed to prevent infections. But a research team led by Associate Professor Alexander Cole of UCF's Bu...

Transmission of antibiotic-resistant bacteria linked to previous intensive care unit room occupants

Staying in a room in the intensive care unit (ICU) previously occupied by a patient with treatment-resistant bacteria may increase the odds of acquiring such bacteria, according to a report in the October 9 issue of Archives of Internal Medicine, one of the JAMA/Archives journals. Two particular microorganisms cause significant illness and death in hospitals: methicillin-resistant Staphylo...

Household transmission of SARS: Lessons learned

In the 2003 outbreak of severe acute respiratory syndrome (SARS) in Toronto, Ontario, about 20% of cases resulted from household transmission (spread of the infection within a household). Wilson-Clark and colleagues studied the characteristics of these household transmissions and report on risk factors that contributed to the spread of infection. Primary risk factors for transmission fall...

Opening windows may be the best way of preventing transmission of airborne infection

A study of eight hospitals in Peru has shown that opening windows and doors provided ventilation more than double that of mechanically ventilated negative-pressure rooms and 18 times that of rooms with windows and doors closed. The researchers, led by Rod Escombe from Imperial College London, compared the airflow in 70 naturally ventilated clinical rooms such as respiratory isolation room...

Changes in amino acids in the 1918 influenza virus cut transmission

Modest changes in the 1918 flu virus's hemagglutinin receptor binding site—a molecular structure critical for the spread of infection—stopped viral transmission in ferrets, according to a new study conducted by researchers at Mount Sinai School of Medicine and at the Centers for Disease Control and Prevention. The finding, published in the February 1 issue of Science, could have significant clini...

Risk of HIV transmission highest early in infection

New evidence suggests that the risk of HIV transmission may be highest in the early stages of infection. According to a study published in the April 1 issue of The Journal of Infectious Diseases, now available online, early infection accounted for nearly half of all transmission occurrences in an HIV-infected population in the province of Quebec, Canada. Bluma Brenner, PhD, and Mark Wainb...

LIAI scientists make important finding on cytomegalovirus transmission

Researchers at the La Jolla Institute for Allergy & Immunology have shown that cytomegalovirus (CMV) in the salivary glands can be reduced ?and in some cases eliminated ?through the use of antibodies to enhance the disease-fighting power of the immune system. The research team’s findings, based on controlled laboratory studies of mice, may also have implications for other chronic virus infec...