Friday, 11 December 2009

26 deaths for every 100,000 cases of swine flu

(Research: Mortality from pandemic A/H1N1 2009 influenza in England: public health surveillance study)

New data, published today on, reveal that there were 26 deaths out of every 100,000 cases of swine flu in England (a fatality rate of 0.026%). The authors conclude that “the first influenza pandemic of the 21 st century is considerably less lethal than was feared in advance.” However, they emphasise that this is not a justification for public health inaction when death, serious illness and admission to hospital can be prevented.

This paper will be published on at 15:00 hrs UK time, Thursday 10 December, to coincide with the Department of Health’s weekly H1N1 update, hosted by the Chief Medical Officer for England , Sir Liam Donaldson.

After the pandemic was announced, from June 2009 the Department of Health in England compelled all primary care trusts and acute hospitals to collate data on individuals who were believed to have died from swine flu. Today’s study is the first analysis of this material and includes all known deaths in England from swine flu up until 8 November 2009. The research, which was carried out by Sir Liam Donaldson’s research team, reveals that two thirds of the patients who died (66.7%) from swine flu would now be eligible for vaccination. The authors say that this demonstrates the importance of getting high risk groups vaccinated. Donaldson and his team also argue that there is a case for extending the vaccination programme to the wider population given that a substantial minority (38%) of deaths occurred in non-high risk groups.

While the over 65’s had less chance of contracting swine flu, the study reveals that this group were more likely to die from the disease if they developed it. The authors argue that perhaps older people were less likely to become infected with swine flu because they had already been exposed to similar strains and that “without this previous exposure, the pandemic might have caused many more deaths in this age group.” The researchers say their fatality rate estimate compares well with the other three 20th century influenza pandemics – the rate for the 1918 Spanish flu was 2-3% and subsequent pandemics (1957-8 and 1967-8) had rates of around 0.2%.

Donaldson argues that “improvements in nutritional status, housing and health care availability might explain some of the apparent decrease in case fatality from one pandemic to the next” and that “since the most recent pandemic there have been major advances in intensive care medicine.” The authors conclude that “many more patients may have died in England without the ready availability of critical care support, including mechanical ventilation.”

Liam Donaldson, Chief Medical Officer for England, Department of Health, Richmond House, London, UK 
Tel (via Kate Pike or Peter Graham): +44 (0)20 7210 5703
Out of hours: +44 (0)7050 073 581 (DH duty press officer)

Saturday, 28 November 2009

Chikungunya fever: an old disease re-emerges

The new era of globalization and environmental change has witnessed the arrival of many new and re-emerging diseases which create new challenges for policy makers and researchers working on infectious diseases. Massive urbanization has facilitated the spread of contagious diseases in human populations due to faster travel over greater distances and worldwide trade. Although more affluent countries are better-equipped to manage the spread and treatment of infectious diseases, it has become increasingly clear that they still face major challenges when dealing with diseases whose boundaries have been expanding due to warmer and wetter weather. A good example of such an abrupt increase in the incidence of disease are infections caused by arboviruses, whose expansion to new geographic areas has been facilitated by the establishment of new vectors. The Chikungunya outbreaks in late 2005 represent a fine example of how a virus originally from Africa and mosquitoes originally from Asia can meet in the Indian Ocean and contribute to re-emergence of a disease, and then spread to other parts of the world.

Chikungunya fever - Re-emergence of an old disease. Lisa F.P. Ng, David M. Ojcius. Microbes and Infection, Volume 11, Issues 14-15, December 2009, Pages 1163-1164

Thursday, 26 November 2009

Lipid Factors From Common Bacteria Could Trigger Multiple Sclerosis

Current research suggests that a common oral bacterium may exacerbate autoimmune disease. The related report by Nichols et al, “Unique Lipids from a Common Human Bacterium Represent a New Class of TLR2 Ligands Capable of Enhancing Autoimmunity,” appears in the December 2009 issue of The American Journal of Pathology.

Multiple sclerosis (MS), a disease where the immune system attacks the brain and spinal cord, affects nearly 1 in 700 people in the United States. Patients with multiple sclerosis have a variety of neurological symptoms, including muscle weakness, difficulty in moving, and difficulty in speech.

Porphyromas gingivalis, a common oral bacterium in humans, produces a unique type of lipid, phosphorylated dihydroceramides (DHCs), which enhance inflammatory responses. These lipids are also likely produced by bacteria found in other parts of the body including the gastrointestinal tract. To determine if these lipids accentuate immune-mediated damage in autoimmune disease, researchers led by Robert B. Clark and Frank C. Nichols of the University of Connecticut Health Center administered phosphorylated DHCs in a mouse model of MS. The severity of disease was significantly enhanced by the addition of these lipids in a manner that was dependent on activation of the immune system. These data suggest that phosphorylated DHCs from bacteria commonly found in humans may trigger or increase the severity of autoimmune diseases such as multiple sclerosis.

The authors state that “while it is clear that the immune system in most individuals has the potential to attack self-tissues, the “tipping” factors that initiate and propagate autoimmune diseases such as multiple sclerosis in only a subset of individuals remain unknown. Overall, [their] results represent the first description that phosphorylated DHCs derived from common human bacteria are capable of enhancing autoimmune disease.” Thus, these lipids may function as “tipping” factors, playing a previously unrecognized role in initiating or exacerbating human autoimmune diseases. In future studies, Dr. Clark and colleagues plan to characterize the effects of phosphorylated DHCs on specific cells of the immune system and to identify how and where these lipids are deposited in tissues throughout the body. In addition to the role of these lipids in triggering and worsening MS, the authors believe that phosphorylated DHCs may have the potential to serve both as new markers of MS disease activity and as new targets for therapeutic intervention.

Nichols FC, Housley W, O’Conor C, Manning T, Wu S, Clark RB: Unique Lipids from a Common Human Bacterium Represent a New Class of TLR2 Ligands Capable of Enhancing Autoimmunity. Am J Pathol 175: 2430-2438.This work was supported by grants from the National MS Society (RG4070-A-6) (RBC) and the Patterson Trust Foundation (FN). There is a provisional patent application pending for the use of bacterial phosphorylated dihydroceramides. This application pertains to Dr. Frank Nichols and Dr. Robert B. Clark.

Ljungan Virus: a Zoonotic Human Pathogen?

Ljungan virus (LV), a picornavirus, was discovered in the Swedish vole population after six clustered deaths from myocarditis were noted in orienteers between 1989 and 1992. Four of five sera from the orienteer patients had detectable antibodies against one of the LV isolates. Researchers tracked data about the population density of Swedish voles carrying LV and compared them to various disease incidences in humans in northern Sweden. Both animal and human data support the possibility that LV causes or contributes to diabetes, fetal death, fetal malformations, and sudden infant death syndrome. Current research has raised the question of the importance of this newly recognized zoonotic pathogen within rodent vectors. Evidence indicates that it would be prudent to consider LV infection in clinical practice, and LV will no doubt be the subject of upcoming intensive research.

Ljungan Virus: an Emerging Zoonosis? Anna Greene McDonald. Clinical Microbiology Newsletter, Volume 31, Issue 23, 1 December 2009, Pages 177-182

Wednesday, 25 November 2009

MRSA Strain on the Rise in Hospitals

Study Shows Community-Associated MRSA Is Spreading in Health Care Facilities. By Bill Hendrick, WebMD Health News.

A potentially dangerous and rapidly spreading strain of the "superbug" MRSA poses a much greater public health threat than previously thought, new research shows.

Community-associated MRSA (CA-MRSA) is spreading in hospitals and other health care facilities, according to a study in the December issue of Emerging Infectious Diseases. The CA-MRSA strain of superbug can be picked up in fitness centers, schools, and other public places, and is increasing the already significant burden of MRSA (methicillin-resistant Staphylococcus aureus) in hospitals, the researchers report. CA-MRSA and hospital-associated MRSA (HA-MRSA) are bacteria resistant to most common antibiotics.

HA-MRSA infections occur mostly in hospitals and other health care settings, including dialysis centers and nursing homes, and often strike mostly older adults, people having invasive medical procedures, and people with weakened immune systems. CA-MRSA is a leading cause of serious skin and soft tissue infections, entering the body through scrapes and cuts, the researchers say.

The study, which analyzed data from more than 300 microbiology labs across the U.S., found a sevenfold increase in the proportion of CA-MRSA in outpatients between 1999 and 2006. This community-associated strain is making its way into hospitals, the researchers say, increasing threats to patient safety because patients and their doctors move back and forth between inpatient and outpatient units of hospitals. "This emerging epidemic of community-associated MRSA strains appears to add to the already high MRSA burden in hospitals," Ramanan Laxminarayan, PhD, MPH, a senior fellow at Extending the Cure, a project at the Resources for the Future think tank in Washington, D.C., says in a news release. This major increase in CA-MRSA, the researchers say, has become a major concern.

Over the length of the study, the scientists report finding that the proportion of MRSA had increased more than 90% among outpatients with staph, and now accounts for more than 50% of all Staphyloccus aureus infections. This was due, the findings suggest, almost entirely to an increase in CA-MRSA strains. Similar increases in inpatients suggest these strains are spreading rapidly into hospitals. "MRSA has generally been a significant problem only in hospitals," says Eili Klein, MA, the lead author of the report and also a researcher at Resources for the Future. "But the findings from this study suggest there is a significant reservoir in the community as well." This suggests that the increased cases of CA-MRSA are causing that bug to spread from the community into hospitals, Klein says.

Hospitals need to take steps to stop this by stepping up infection control procedures, the researchers say, adding that the best way to contain MRSA and other superbugs is through surveillance and regular efforts aimed at infection control. "Community-associated methicillin-resistant Staphylococcus aureus has become a major problem in U.S. hospitals already dealing with high levels of hospital-associated MRSA," the researchers write. They conclude that "more rapid diagnostic methods are urgently needed to better aid physicians" in fighting MRSA.

SOURCES: News release, Emerging Infectious Diseases, Burness Communications. 

Klein, E. Emerging Infection Diseases, December 2009; vol 15.

Cigarettes harbour bacterial pathogens

New research shows that cigarettes contain hundreds of different strains of bacteria, including many human pathogens that may play a role in lung diseases and respiratory infections.

Foodborne Illness

Foodborne Illness: An Acute And Long-term Health Challenge For The 21st Century
The Center for Foodborne Illness Research & Prevention (CFI) has released a report that documents what is currently known about the long-term health outcomes associated with several foodborne illnesses. The report also discusses how under-reporting, inadequate follow-up and a lack of research make it difficult to assess the impact that foodborne illness is having on Americans.

CFI's report, The Long-Term Health Outcomes of Selected Foodborne Pathogens, calls for a new approach to foodborne illness research and surveillance and provides expert reviews about some of the long-term health outcomes for five foodborne pathogens. The outcomes range from hypertension and diabetes to kidney failure and mental retardation.

"Foodborne illness is a serious public health issue in the 21st century," says Dr. Tanya Roberts, Chair of CFI's Board of Directors and an author of the report. "But the vast majority of these illnesses are never reported to public health agencies, leaving us with many unanswered questions about the impact that foodborne illness is having on different populations, particularly young children and the elderly."

The five foodborne pathogens reviewed in this report include:

  1. Campylobacter infection afflicts millions of Americans and hospitalizes over ten thousand annually. It is associated with Guillain-Barré syndrome (GBS), the most common cause of neuromuscular paralysis in the United States. GBS can result in permanent disabilities and many patients require long-term care. 

  2. E. coli O157:H7 can cause serious foodborne illness, particularly in children. E. coli O157:H7 can lead to hemolytic uremic syndrome (HUS), the leading cause of acute kidney failure in children in the United States. HUS can lead to death or long-term health complications such as end-stage kidney disease, neurological complications and other disabling conditions. 

  3. Listeria monocytogenes, the leading cause of foodborne illness deaths in the United States, infects thousands of Americans every year and has been associated with infections of the brain and spinal cord, resulting in serious long-term neurological dysfunctions and impaired ability to see, hear, speak or swallow. Most reported cases occur in children under the age of 4, but most of the deaths are in the elderly population. In pregnant women, listeriosis can cause miscarriage, premature birth or still birth. 

  4. Salmonella, as well as other foodborne pathogens, can trigger reactive arthritis (ReA) in certain individuals, leaving them with temporary or permanent arthritis. ReA causes painful and swollen joints and can greatly affect an individual's ability to work and quality of life. Besides ReA, Salmonella is also associated with many other complications and is the second leading cause of foodborne illness deaths in the United States. Nearly half of all reported Salmonella cases occur in children. 

  5. Toxoplasma gondii is the third leading cause of foodborne illness deaths in the United States. Infection can result in visual impairment or mild to severe mental retardation, with 80% of infected fetuses/infants manifesting impairment by age 17.
"Clearly, the United States needs to adopt a new approach to protect its citizens from the acute and long-term effects of foodborne illness," states Barbara Kowalcyk, CFI's Director of Food Safety and an author of the report. "Improving foodborne illness surveillance, along with systematic follow-up and improved data sharing between and among local, state and federal agencies, are important first steps to increase our knowledge about the frequency and severity of the long-term health outcomes of foodborne illness, which will, in turn, help identify food safety priorities so that limited resources can be applied appropriately to ensure the greatest public health benefit."

Other co-authors of the report include Patricia Buck, CFI's Executive Director; Martin J. Blaser, M.D.; J.K. Frenkel, M.D.; Bennett Lorber, M.D.; James Smith, Ph.D.; Phillip I. Tarr, M.D.

Source: Patricia Buck
Pew Health Group

Mycotoxins or Prokaryotoxins?

Mycotoxins are compounds of fungal origin that can adversely affect human, animal and plant health through food spoilage or infection, even to the point of epidemics such as turkey X disease and ergotism. The biosynthetic pathways of various mycotoxins (such as aflatoxin and fumonisins) are generally well understood. However, two examples have recently been described where a mycotoxin is not synthesized by the fungus itself but by bacteria residing within the fungal cytosol. These discoveries have implications in various fields, such as ecology, medicine and food processing.

Endofungal bacteria as producers of mycotoxins. Gerald Lackner, Laila P. Partida-Martinez, Christian Hertweck. Trends in Microbiology, Volume 17, Issue 12, December 2009, Pages 570-576.

Virus could cause prostate cancer

Worldwide, approximately 3% of men die from prostate cancer. The lifetime risk in developing prostate cancer is 1 in 6 (US). Xenotropic murine leukemia virus–related virus (XMRV) was discovered recently in human prostate cancers. It is the first gammaretrovirus that is known to infect humans.

XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors. PNAS USA September 8 2009 doi:10.1073/pnas.0906922106

Thursday, 19 November 2009

Pseudomonas aeruginosa

Pseudomonas aeruginosa is a versatile pathogen associated with a broad spectrum of infections in humans. In healthcare settings the bacterium is an important cause of infection in vulnerable individuals including those with burns or neutropenia or receiving intensive care. In these groups morbidity and mortality attributable to P. aeruginosa infection can be high. Management of infections is difficult as P. aeruginosa is inherently resistant to many antimicrobials. Furthermore, treatment is being rendered increasingly problematic due to the emergence and spread of resistance to the few agents that remain as therapeutic options. A notable recent development is the acquisition of carbapenemases by some strains of P. aeruginosa. Given these challenges, it would seem reasonable to identify strategies that would prevent acquisition of the bacterium by hospitalised patients. Environmental reservoirs of P. aeruginosa are readily identifiable, and there are numerous reports of outbreaks that have been attributed to an environmental source; however, the role of such sources in sporadic pseudomonal infection is less well understood. Nevertheless there is emerging evidence from prospective studies to suggest that environmental sources, especially water, may have significance in the epidemiology of sporadic P. aeruginosa infections in hospital settings, including intensive care units. A better understanding of the role of environmental reservoirs in pseudomonal infection will permit the development of new strategies and refinement of existing approaches to interrupt transmission from these sources to patients.

Pseudomonas aeruginosa: a formidable and ever-present adversary
Journal of Hospital Infection, Volume 73, Issue 4, December 2009, Pages 338-344
K.G. Kerr, A.M. Snelling


Acinetobacter emerged as a significant nosocomial pathogen during the late 1970s, probably as a consequence, at least in part, of increasing use of broad-spectrum antibiotics in hospitals. Most clinically significant isolates belong to the species Acinetobacter baumannii or its close relatives, with many infections concentrated in intensive care, burns or high dependency units treating severely ill or debilitated patients. Large outbreaks can occur in such units, involving the infection or colonisation of numerous patients by specific epidemic strains of A. baumannii. Recently, a particular problem has concerned cross-infection of injured military patients repatriated from combat regions of the world (e.g. Iraq and Afghanistan). Carbapenems have previously been the treatment of choice for infected patients, but increasing reports worldwide now describe A. baumannii isolates resistant to all conventional antimicrobial regimens. Data to support therapeutic use of the limited number of new antimicrobial agents (e.g. tigecycline) with in-vitro activity against these pathogens are still very limited. Detailed advice concerning prevention and control of outbreaks caused by multidrug-resistant strains of acinetobacter is available from the UK Health Protection Agency. In addition to antibiotic prescribing policies and audit, these measures focus on reinforcing standard infection control procedures and precautions, with particular attention to thorough cleaning of patient areas to take account of the long-term survival of acinetobacter after drying and inadequate disinfection. Despite these measures, the problem continues to escalate, with many hospitals worldwide now reporting outbreaks caused by multidrug-resistant strains of acinetobacter.

Acinetobacter: an old friend, but a new enemy
Journal of Hospital Infection, Volume 73, Issue 4, December 2009, Pages 355-363
K.J. Towner

Cronobacter: A new seperate genus

Enterobacter sakazakii is a member of the Enterobacteriaceae that has been implicated in causing necrotising enterocolitis, bacteraemia and meningitis in infants. The nomenclature of this species has been clarified recently and it has now been accepted as a separate genus, Cronobacter.

International Journal of Food Microbiology, Volume 136, Issue 2, 31 December 2009, Pages 169-178. Cronobacter Special Issue

Tuesday, 17 November 2009

Breakthrough in fight against deadly Hendra virus

There has been a breakthrough in the fight against the deadly Hendra virus following the development of a treatment which shows great potential to save the lives of people who become infected with the virus. First identified in Brisbane and isolated by CSIRO scientists in 1994, Hendra virus, which spreads from flying foxes, has regularly infected horses in Australia. Of the 12 equine outbreaks, four have led to human infection, with four of the seven known human cases being fatal, the most recent of these in September 2009. Human infection results from close contact with the blood and/or mucus of infected horses.

Mouthy Bacteria

Recent research suggests that the human mouth contains as many as 19,000 bacterial phylotypes.
J Dent Res 2008. 87, 1016–20.

Monday, 16 November 2009

A few snippets about tuberculosis

Individuals are assumed to have contracted and died from Mycobacterium tuberculosis infection as long ago as 15,000 years. The oldest fossil records are from Africa. In 1882, Robert Koch, who discovered the tubercle bacillus, estimated that one in seven deaths in Berlin was caused by tuberculosis. Today, about one-third of the world's population is infected with M. tuberculosis. Eight million people develop the disease each year. Of these, approximately 2 million die annually, with most of the deaths occurring in developing countries.
The story of tuberculosis, also called the “white plague,” is the story of the first modern day clinical trial. Selman Waksman was the first to discover that streptomycin was effective against M. tuberculosis; he subsequently won a Nobel Prize in medicine for this work. The history of tuberculosis is also the history of sanatoriums, where tuberculosis patients went to “take the cure” before anti-tuberculous therapy was available. These special hospitals allowed M. tuberculosis patients to breathe fresh, clean air; eat nutritious foods; and rest. The introduction of isoniazid in 1954 finally led to the closing of sanatoriums.

Infectious Diseases and Famous People Who Succumbed to Them
Clinical Microbiology Newsletter, Volume 31, Issue 22, 15 November 2009, Pages 169-172
Alice S. Weissfeld

Staphylococcus aureus transmitted from paper currency

Infection with Staphylococcus aureus was initially considered a major problem in hospitals, but over the last few decades the incidence of community-acquired infection has also increased. Paper currency has recently been identified as another mode of spread by which community-acquired S. aureus infection may be transmitted, since paper currency is frequently transferred from one person to another.

Detection of virulence genes in Staphylococcus aureus isolated from paper currency
International Journal of Infectious Diseases, Volume 13, Issue 6, November 2009, Pages e450-e455
J. Dinesh Kumar, Yogesh K. Negi, Abhishek Gaur, Deepshikha Khanna

Cigarette Smoke May Impair Lungs Natural Defense Against Harmful Pathogen

Exposure to cigarette smoke may impair the ability of immune cells to clear bacterial infections from the lungs, specifically nontypeable Haemophilus influenzae (NTHI), a pathogen often associated with respiratory infections and the progression of respiratory diseases.
P. Marti-Lliteras, V. Regueiro, P. Morey, D.W. Hood, C. Saus, J. Sauleda, A.G.N. Agusti, J.A. Bengoechea, J. Garmendia. 2009. Nontypeable Haemophilus influenzae clearance by alveolar macrophages is impaired by exposure to cigarette smoke. Infection and Immunity, 77. 10: 4232-4242.)

Pumpkin Skin Antibiotic

The skin of that pumpkin you carve into a Jack-o'-Lantern to scare away ghosts and goblins on Halloween contains a substance that could put a scare into microbes that cause millions of cases of yeast infections in adults and infants each year.

Wednesday, 11 November 2009

Frigid Antarctica Loaded with Viruses | LiveScience

Frigid Antarctica Loaded with Viruses | LiveScience: A lake in Antarctica was found to harbor a surprising variety of viruses. Here, an image of the Spanish, non-permanent camp in Byers Peninsula (Livingston Island, Antarctica). Credit: Science/AAAS.
Full Size
1 of 3
Antarctica's icy lakes are home to a surprisingly diverse community of viruses, including some that were previously unidentified, a new study finds.

Monday, 5 October 2009

Swine Flu Vaccine Misinformation


I didn't know there were so many dangerous people in the world. But then I came to this YouTube entry! The comments and advice could be life-threatening!

If anyone took the time to read the insert for any medication they would see a long list of POSSIBLE side-effects, that for most drugs have a small chance of occurring, and certainly after rigorous clinical trials are deemed to be outweighed by the benefits. Nothing is perfect in this life and we must be vigilant with all things that affect our wellbeing. But please don't be put off by the comments in the YouTube article from making a sensible judgement on whether your risk of exposure to flu, and your preexisting health or health history warrant taking or not taking the available vaccine. And please do this, if possible, with help and advice from your doctor or other knowledgeable medical professional (e.g. phamacist).

Remember, the inserts for drugs show that the company and government are prepared to be honest and upfront about the risks. But to make use of the information you need to get educated about what they mean, especially in terms of the chances they might occur relative to your own health history, and importantly what your risks are if you don't take the medication.

Influenza can be a serious illness, especially for certain individuals with present health issues, including immune disorders. And don't forget the "unknown" preexisting conditions that individuals can have. When was the last time you had a health check?

I am not a medical doctor, but I feel I am well enough informed to make comments on this issue. I have taken the time and effort to find facts, and not just anecdotes. The instantly made alarmist reactions from the internet are most often not facts, they are lay opinions. Having said that, many people make comments with the best intentions, although the information they give might be flawed. Mix this with the views of nutcases and the completely diversionary religious inserts (as in the YouTube article’s comments) and the outcome can be simply misinformation. This can be unhelpful and even dangerous. Of course, there are also examples of fallacious "medical" opinion, a notable example being the incorrect interpretations and advice from certain UK doctors about the MMR vaccine that led to major problems in its uptake due to concerned parents believing the (very small) minority opinion rather than reading widely and deeply. Now the consensus is that MMR is safe, but there was not real evidence to refute this originally had people looked! The media had a field day and due to their scaremongering many children have gotten ill.

To conclude, get hold of the medical/scientific facts (independently and from a doctor), discuss the issues widely and deeply, think long and hard about the benefits, think long and hard about the alternatives and their possible consequences, and then make the decision. You can't do more than that and so then whatever your decision it will be the right one, but YOU will have to live (or not) with the consequences!