MedicineWorld.Org
Your gateway to the world of medicine
Home
News
Cancer News
About Us
Cancer
Health Professionals
Patients and public
Contact Us
Disclaimer

Medicineworld.org: Archives of infectious disease blog


Go Back to the main infectious disease blog

Subscribe To Health Blog RSS Feed  RSS content feed What is RSS feed?

Archives Of Infectious Disease Blog From Medicineworld.Org


June 19, 2007, 5:02 AM CT

Predicting Danger of Flu Pandemic

Predicting Danger of Flu Pandemic
Researchers studying the potential spread of a flu pandemic must be careful to distinguish the different rates of infection among different groups, including the sociable and the shy, those most susceptible to infection and those less so, as per a new study in the "O.R. Forum" section of Operations Research, a flagship journal of The Institute for Operations Research and the Management Sciences (INFORMS®).

In the study, "Simple Models of Influenza Progression Within a Heterogeneous Population," Dr. Richard C. Larson, a former president of INFORMS and a professor at MIT, discusses the importance of forecasting and ultimately limiting the spread of disease while taking into account the different infection rates among those who might contract the disease.

"We allow for socially active people who interact with a number of other people on a given day, and we allow for relatively inactive people who interact with few others," he writes. "We provide for highly susceptible people who are more likely to become infected once exposed to the virus, and we include those who are less susceptible. In a similar vein, we allow for highly contagious as well as less contagious infected persons.

"The reasoning behind these assumptions is that heterogeneity across the population in these attributes may affect in first-order ways the manner in which the disease propagates and, consequently, the manner in which we should address mitigation measures."........

Posted by: Mark      Read more         Source


June 15, 2007, 11:05 AM CT

Infectious diseases experts issue warnings

Infectious diseases experts issue warnings
New vaccines are available to make significant gains against cervical cancer deaths and debilitating pain from shingles, but infectious diseases experts warn that their full potential will not be realized without changes in the way vaccines for adults and adolescents are promoted, financed, and delivered in the United States.

The Infectious Diseases Society of America (IDSA) has released a new blueprint for action to prevent tens of thousands of deaths and illnesses caused by these and other diseases that can be avoided with a few simple shots. The blueprint is reported in the June 15 issue of Clinical Infectious Diseases.

We have done a great job in this country delivering vaccines to children, but we have done an awful job delivering vaccines to adults, said Neal A. Halsey, MD, professor at the Johns Hopkins University Bloomberg School of Public Health and chair of the IDSA Immunization Work Group that developed the policy blueprint.

For example, he points out that more than 90 percent of U.S. children are immunized against measles, mumps, whooping cough, hepatitis B, and other diseases. Rates of these diseases are at or near historic lows. In contrast, an estimated 175,000 adults are hospitalized and 6,000 die each year from pneumococcal pneumonia, but one in three adults over 65 has not been vaccinated against it. The Centers for Disease Control and Prevention (CDC) estimates that the cost of treating diseases that vaccines could prevent exceeds $10 billion annually.........

Posted by: Mark      Read more         Source


June 12, 2007, 5:06 AM CT

Antibiotic use in infants linked to asthma

Antibiotic use in infants linked to asthma
New research indicates that children who receive antibiotics before their first birthday are significantly more likely to develop asthma by age 7. The study, reported in the recent issue of CHEST, the peer-evaluated journal of the American College of Chest Physicians (ACCP), reports that children receiving antibiotics in the first year of life were at greater risk for developing asthma by age 7 than those not receiving antibiotics. The risk for asthma doubled in children receiving antibiotics for nonrespiratory infections, as well as in children who received multiple antibiotic courses and who did not live with a dog during the first year.

Antibiotics are prescribed mostly for respiratory tract infections, yet respiratory symptoms can be a sign of future asthma. This may make it difficult to attribute antibiotic use to asthma development, said lead study author Anita Kozyrskyj, PhD, University of Manitoba, Winnipeg, MB. Our study reported on antibiotic use in children being treated for nonrespiratory tract infections, which distinguishes the effect of the antibiotic.

By using a prescription database, Dr. Kozyrskyj and his colleagues from the University of Manitoba and McGill University in Montreal were able to monitor the antibiotic use of 13,116 children from birth to age 7, specifically noting antibiotic use during the first year of life and presence of asthma at 7. The reason for antibiotic use was categorized by lower respiratory tract infection (bronchitis, pneumonia), upper respiratory tract infection (otitis media, sinusitis), and nonrespiratory tract infection (urinary infections, impetigo). Risk and protective factors also were noted, including gender, urban or rural location, neighborhood income, number of siblings at age 7, maternal history of asthma, and pets reported living in the home. Within the study group, 6 percent of children had current asthma at age 7, while 65 percent of children had received at least one antibiotic prescription during the first year of life. Of the prescriptions, 40 percent of children received antibiotics for otitis media, 28 percent for other upper respiratory tract infections, 19 percent for lower respiratory tract infections, and 7 percent for non-respiratory tract infections. Results showed that antibiotic use in the first year was significantly linked to greater odds of asthma at age 7. This likelihood increased with the number of antibiotic courses, with children receiving more than four courses of antibiotics having 1.5 times the risk of asthma compared with children not receiving antibiotics. When scientists compared the reason for antibiotic use, their analysis indicated that asthma at age 7 was almost twice as likely in children receiving an antibiotic for nonrespiratory tract infections compared with children who did not receive antibiotics.........

Posted by: JoAnn      Read more         Source


June 7, 2007, 7:35 PM CT

How bacteria to resist human immune defenses

How bacteria to resist human immune defenses
Scientists at the National Institute of Allergy and Infectious Diseases (NIAID), a component of the National Institutes of Health, have discovered a survival mechanism in a common type of bacteria that can cause illness. The mechanism lets the bacteria protect itself by warding off attacks from antimicrobial peptides (AMPs), which are defense molecules sent by the body to kill bacteria.

Bacteria are divided into two types, gram-positive and gram-negative, with the primary difference being the nature of the bacterial cell wall. Little is known about how gram-positive bacteriasuch as those that can lead to food poisoning, skin disorders and toxic shockavoid being killed by AMPs. AMPs are made by virtually all groups of organisms, including amphibians, insects, several invertebrates and mammals, including humans.

Gram-positive bacteria are major threats to human health, particularly due to increasing problems with drug resistance, and these findings may help chart a path to designing new drugs to bolster our antimicrobial therapy options, notes NIAID Director Anthony S. Fauci, M.D.

Led by Michael Otto, Ph.D., of NIAIDs Rocky Mountain Laboratories (RML), the researchers used the gram-positive bacterium Staphylococcus epidermidis to study its response to a specific human AMP, human beta defensin 3. S. epidermidis is one of several hard-to-treat infectious agents that can be transmitted to patients in hospitals via contaminated medical implants. Findings by Dr. Ottos research group are reported in the May 29 issue of the Proceedings of the National Academy of Science. Other well-known types of gram-positive bacteria include agents that cause anthrax, strep throat, flesh-eating disease and various types of food poisoning.........

Posted by: Mark      Read more         Source


June 6, 2007, 9:57 PM CT

Insights Into Anti-malarial Drug Resistance

Insights Into Anti-malarial Drug Resistance
Scientists at Georgetown University Medical Center say they are moving closer to understanding why the most lethal form of human malaria has become resistant to drug therapy in the past three decades. They have been able to artificially construct, and then express in yeast, a protozoan gene that contributes to such resistance. And it was no small feat. The gene they laboriously constructed over a two-year period is thought to bethe largest "synthetic" one ever built, and it successfully produces large quantities of the encoded protein, whose function can now be easily studied.

In research reported in the May 22 issue of the journal Biochemistry, the scientists say that with the addition of the recreated gene, PfMDR1 and its protein, they have all the biomolecular tools necessary to molecularly understand how the malarial parasite Plasmodium falciparum (P. falciparum), has become resistant to most of the drugs that could once destroy it. They have already described and expressed two other genes known to confer drug resistance.

"Now that we have these genes expressed in a convenient yeast system, we can work to understand the molecular basis of anti-malarial drug resistance, providing insight into how future drugs might be designed to effectively kill the parasite," said Paul Roepe, PhD, a professor in the Department of Biochemistry and Cellular & Molecular Biology and the Department of Chemistry.........

Posted by: Mark      Read more         Source


June 6, 2007, 9:17 PM CT

New Bacterium That Cause Of Trench Fever

New Bacterium That Cause Of Trench Fever
Jane Koehler, MD
A close cousin of the bacterium that debilitated thousands of World War I soldiers has been isolated at UCSF from a patient who had been on an international vacation. The woman, who has since recovered, suffered from symptoms similar to malaria or typhoid fever, two infections that can occur in returning travelers.

But genetic detective work revealed that she was infected with a new bacterium that had never before been isolated from a human.

A UCSF infectious disease team, in collaboration with colleagues from other institutions, observed that the new microbe is genetically similar to one spread by body lice in the trenches during World War I. That bacterium, called Bartonella quintana, caused a disease known as trench fever, and debilitated tens of thousands of soldiers with severe leg and back pain and recurrent fevers.

The new species, recently named Bartonella rochalimae, is also closely correlation to the bacterium identified about 10 years ago as the cause of cat scratch disease: Bartonella henselae, which infects more than 25,000 people a year in the U.S.

The discovery is published in the June 7 issue of The New England Journal (NEJM).

The woman had been traveling in the Peruvian Andes. She suffered from potentially life-threatening anemia, an enlarged spleen and a high fever for several weeks, as do victims of malaria and typhoid. The Andes are also home to another Bartonella species, spread by sand flies. The scientists first thought this was causing the patients infection.........

Posted by: Mark      Read more         Source


June 1, 2007, 9:37 PM CT

Innovative Smallpox Vaccine Research Study

Innovative Smallpox Vaccine Research Study
University Hospitals Case Medical Center (UHCMC) and Case Western Reserve University School of Medicine are part of a nationwide research study to determine the safety and effectiveness of a new smallpox vaccine geared toward adults ages 18 to 34 who have never been vaccinated against the disease. The study is the first of its type in Northeast Ohio.

The current FDA-approved vaccine, Dryvax®, is not recommended for use on everyone because of the potential for serious side effects in certain individuals. "For example, the current vaccine cannot be used in immune-compromised individuals, such as patients with HIV or individuals with certain skin conditions such as eczema," says Robert A. Salata, M.D., chief of the Division of Infectious Diseases at Case Western Reserve University School of Medicine and UHCMC.

The new vaccine, IMVAMUNE®, is different from Dryvax® in that it contains a more weakened form of the live-virus within the vaccine.

"Because the vaccine is weakened, the side effects should be minimized enough to give the vaccine to all individuals, even those whose immune systems are suppressed," says Dr. Salata. "Our hope is that the new vaccine will be a safer alternative to the current vaccine".

UHCMC and the School of Medicine will act as a subunit of St. Louis University's Center for Vaccine Development, which is one of seven national testing sites known as Vaccine and Treatment Evaluation Units (VTEUs), designated by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.........

Posted by: Mark      Read more         Source


May 30, 2007, 0:03 AM CT

'Nurse cells' make life and death decisions

'Nurse cells' make life and death decisions
Thymocytes are taken up by thymic "nurse" cells.
Credit: Jerry Guyden, CUNY
"Nurse cells" play an important role in deciding which developing infection-fighting cells, called T cells, live and which die, as per research funded by the National Science Foundation (NSF) and published in the recent issue of the journal Experimental Biology and Medicine.

The infection-fighting cells, known as thymocytes or T cells, live in the thymus, an organ in the upper portion of the chest. Loss of the thymus results in severe immunodeficiency and increased susceptibility to infection. The function of T cells produced by the thymus is to recognize harmful invaders. Once invaders have been identified, T cells then attempt to eliminate disease-infected cells.

"In early studies, it was suggested that thymic nurse cells only removed non-functional thymocytes," said Eve Barak, program director in NSF's Division of Molecular and Cellular Biology. "This research shows that nurse cells are performing a much bigger role in the thymus than we thought".

Thymic nurse cells were given their name because of their close relationship with thymocytes. These nurse cells have been reported to take up as a number of as 50 destined-to-die thymocytes into their own cell bodies.

Thymic nurse cells were discovered in 1980. Their existence was debated because a number of researchers found it difficult to think that a cell could internalize another cell, said Jerry Guyden, a biologist at the City College of New York and lead researcher.........

Posted by: Mark      Read more         Source


May 29, 2007, 11:54 PM CT

Potential for a broadly-protective HIV vaccine

Potential for a broadly-protective HIV vaccine
New research conducted at the Uniformed Services University of the Health Sciences (USU) suggests that it may be possible to develop a vaccine that protects against the myriad strains of the HIV virus. HIV is extremely variable, so an effective vaccine may need to stimulate the body to produce cross-reactive antibodies that will neutralize multiple viral strains. These results demonstrate that induction of truly broad-spectrum neutralizing antibodies may be an achievable goal. This groundbreaking study titled: Extensively Cross-Reactive Anti-HIV-1 Neutralizing Antibodies Induced by gp140 Immunization appears this week in the Early Edition of Proceedings of the National Academy of Sciences http://www.pnas.org/papbyrecent.shtml.

To be effective, an HIV vaccine must induce the body to produce cross-reactive antibodies that can neutralize multiple strains. USU Professors CAPT Gerald Quinnan, Jr., M.D., USPHS, and Christopher Broder, Ph.D., and their colleagues at USU attempted to elicit these broad-range antibodies in an animal model by immunizing with a particular HIV-1 surface protein, designated R2 gp140, and an immune response-boosting component. The scientists tested antibodies generated by the immunizations to determine their effectiveness in neutralizing the infectivity of a variety of HIV-1 strains. Antibodies produced as a result of immunization neutralized all 48 strains of HIV-1 tested. The results are encouraging for vaccine development, because they showed that it is possible to elicit a broad-spectrum antibody response.........

Posted by: Mark      Read more         Source


May 23, 2007, 10:05 PM CT

Guideline For Treating Lyme Disease

Guideline For Treating Lyme Disease
A guideline developed by the American Academy of Neurology finds conventionally recommended courses of antibiotics are highly effective for treating nervous system Lyme disease. However, there is no compelling evidence that prolonged therapy with antibiotics has any benefit in treating symptoms that persist following standard treatment. The guideline is published May 23, 2007, in the online edition of Neurology, the scientific journal of the American Academy of Neurology.

Lyme disease, an infectious disease caused by tick-borne bacteria, affects the nervous system in 10 to 15 percent of infected patients.

"While other guidelines exist to help diagnose and treat general Lyme disease, there continues to be considerable controversy and uncertainty about the best approach to treating neuroborreliosis, in which Lyme disease involves the nervous system," said lead guideline author John J. Halperin, MD, with Atlantic Health in Summit, NJ, and Fellow of the American Academy of Neurology.

To develop the guideline, the authors analyzed all available scientific studies on the topic.

The evidence shows that using antibiotics for two to four weeks is highly effective for treating neuroborreliosis. Lyme disease responds well to the intravenous antibiotics penicillin, ceftriaxone, cefotaxime, and oral doxycycline, and these antibiotics are probably safe and effective when taken for 14 to 28 days by children and adults.........

Posted by: Mark      Read more         Source



Older Blog Entries   1   2   3   4   5   6   7   8   9   10   11   12   13   14   15   16   17   18   19   20   21   22  

Did you know?
Scientists at Baylor College of Medicine in Houston have found a genetic marker that may identify individuals at greater risk for life-threatening infection from the West Nile virus. Results of the study are reported in the Nov. 15 print edition of Journal of Infectious Diseases.

Medicineworld.org: Archives of infectious disease blog

SARS Main| SARS Abroad| SARS and Goverment| SARS Information in different languages| Media about SARS| Physicians resources for SARS| Reference information for SARS| Updates on SARS|

Copyright statement
The contents of this web page are protected. Legal action may follow for reproduction of materials without permission.