Archive for the ‘Governmental Efforts’ Category

The 1918 flu virus and its descendants: Part 2 Rediscovering the culprit

Sunday, May 13th, 2012

many other major pandemics were associated with rodents, but not the 1918 flu

I re-read my last post a day after writing it and amended the first line, since I found it misleading. It was the worst flu pandemic ever, but I knew that smallpox, the Black Plague, AIDS, malaria and perhaps even typhus each have caused nearly as many or even more deaths over a period of years. I eventually found a rather strange, non-medical website with the "7 Worst Killer Plagues in history," and confirmed my belief that no other bacteria or virus had wreaked as much havoc in brief span of time as the 1918-1919 H1N1 influenza virus.

I wanted to find out what happened to that highly pathogenic organism and, after searching the web, realized the PBS article on the "Spanish flu" was a good place to start. It mentions that the influenza virus was not identified until 1933 and that the actual genetic identity of the particular strain involved in that pandemic (as opposed to the basic type...H1N1) was not identified for many years. The influenza virus responsible for the 1918-1919 pandemic has had many descendants, none as deadly as their ancestor.

In 1950, Johan V Hultin, a graduate student starting his doctoral studies in microbiology, got a clue from a visiting professor who suggested hunting for the virus in bodies buried 32 years prior in the permafrost of the Arctic. Hultin and his faculty advisor traveled to Alaska where flu among the Inuits had been especially deadly with 50 to 100% death rates in five villages.

early days in the Far North

Gold miners, under contract with the Territorial government, had served as grave diggers in 1918-1919 and tissue samples were recovered from four bodies exhumed in 1951. Pathology slides fit with viral lung damage and, in some cases, secondary bacterial pneumonia. But tissue cultures from the samples did not cause disease in ferrets and no influenza virus was recovered.

It wasn't until 1995 that science had advanced enough to for researchers to start the work necessary to identify the virus's unique features. Jeffrey Taubenberger, a molecular pathologist then working at the Armed Forces Institute of Pathology (AFIP), began a ten-plus-year-long project starting with autopsy tissues from the time of the pandemic that had been preserved in the National Tissue Repository. His project was stimulated by a paper published in the journal Science in February, 1995, in which preserved tissue samples from the famous British scientist John Dalton (often called the father of modern atomic theory) were examined. Dalton was color-blind and had donated his eyes at his death in 1844 to determine the cause of the defect; his DNA was studied 150 years later and the resultant publication gave Taubenberger the impetus to do the same with the flu virus.

Hultin read the first paper from Taubenberger's group, wrote to him and eventually went back to Alaska to exhume more flu victims. One was an obese woman whose lungs had the findings of acute viral infection. Samples of these permafrost-preserved tissue had RNA incredibly similar to those obtained from the AFIP National Tissue repository.

And so began an amazing chapter in the history of virology.

Toxins for tots and the rest of us too: part one

Saturday, March 24th, 2012

This speaks for itself

All of us are exposed to potentially dangerous substances in many of our household products, but there's been increasing concern that pregnant women need to pay special attention to  the ever-growing list of chemicals around the home. I just read an article published in The New York Times nine days ago with the gripping title "Is It Safe to Play Yet?" The subtitle described what's going on in many families: "Going to Extreme Lengths to Purge Household Toxins."

I found a reference to an extraordinary study which examined umbilical cord blood samples drawn from ten infants of minority heritage: African-American, Asian or Hispanic. Five independent laboratories were involved and up to 232 toxic chemicals were found. I was familiar with the Environmental Working Group, one of the two non-profits who commissioned the research, but not with Rachel's Network which I found online. It's a women's organization named in honor of Rachel Carson whose book, Silent Spring, in many aspects launched the modern environmental movement.

EWG had been unable to find any published studies focused on minority group infants, yet some of their homes are more likely to be situated near busy highways and roads, to be closer to industrial shops and factories and to have been built before current safety standards were established.

Other studies have found up to 358 chemicals in cord blood of US infants; some are acknowledged as possible cancer-causing agents, nervous-system toxins or endocrine hormone disrupters. The National Institute of Environmental Health Sciences (NIEHS), part of NIH, says those latter toxins can be found in metal food cans, plastic bottles, food, toys, cosmetics, detergents, pesticides and flame retardants. Their adverse effects have increased potential to harm fetuses and young babies as their bodies develop.

asbestos can cause mesothelioma, a rare cancer usually of the lining of the lungs and chest cavity

Our Toxic Substances Control Act, is a 1976 law that, unfortunately, grandfathered most existing chemicals. The Environmental Protection Agency (EPA) was mandated to protect the public by regulating the manufacture and sale of chemicals But 60,000 chemicals were excluded because they were already in use and over the following years the EPA succeeded in restricting only five of those: one was asbestos, but two years after the chemical was banned the rule was overturned by the Fifth Circuit Court as being too broad.

In contrast, the European Union, in 2007, passed REACH, the Registration, Evaluation, Authorisation and Restriction of Chemicals act that applies to all chemical substances; not only those used in industrial processes but also in day-to-day lives, for example in cleaning products, paints as well as in articles such as clothes, furniture and electrical appliances.

REACH places the burden of proof on companies. To comply with the regulation, companies must identify and manage the risks linked to the substances they manufacture and market in the EU. They have to demonstrate to a governmental agency how the substance can be safely used, and they must communicate those risk management measures to the users.

One estimate, published in Health Affairs in 2011, estimated the US spends $76.6 billion a year on kids' medical issues that may be related to their environment.

We have a long ways to go, both in determining which chemicals are actually risky and banning or controlling their use.

And, on the other hand, knowing which chemicals, old and new, are safe for us and our offspring.

Influenza H5N1 HPAI research: lots of viewpoints

Friday, March 16th, 2012

When experts disagree, who should we believe?

Shortly after I wrote my post on the dangers of H5N1 HPAI, my weekly copy of JAMA, AKA the Journal of the American Medical Association, arrived containing a commentary titled "International Debate Erupts over Research on Potentially Dangerous Flu Strains." The pros and cons of release of the two groups' research were discussed and the rationale for publishing the methods and details was explained.

One expert in the field had a balanced view. He felt release of the details of the recent research on H5N1 HPAI might be extremely useful to  those who evaluate which strains of influenza are about to pose a real threat to humans and could potentially cause epidemics. Doing so might provide lead time for other scientists who work on vaccines to prevent wider spread of the particular strain of flu.

But in a January, 2012 online discussion of the controversy the head of a university Center for Biosecurity felt the lives of hundreds of millions of people could be at risk if such an engineered virus strain were to be released, even accidentally. He feels that continued research would require the level of biosecurity utilized with other dire agents such as smallpox.

The first infectious disease specialist countered with the concept that H5N1 HPAI wasn't an especially likely pick for those interested in bioterroism. It's certainly not a selective weapon and its use would require considerable expertise.

The second expert noted there had been no data that such a strain of flu would ever develop naturally, outside the lab, and we had to return to the concept of weighing potential harm versus good.

Now the original researchers have stated that the new viral subtype isn't as deadly as feared; it hasn't killed the ferrets being used as laboratory substitutes for humans and has proven to be controllable with vaccines and antiviral medications. Because of ethical limitations it hasn't been tried on human subjects and they don't know whether it even could be spread among humans.

And which of these is the worst?

I think we're treading very close to the edge here. I don't look forward to widespread beneficial effects of complete publication of the ongoing lab research results. And I do fear the possibility of groups who don't care if they kill off a third of everyone, including their own followers. Accidental release of a lab-engineered organism into the human population could also happen, even if unlikely.

Another online article said the work on the mutant form of H5N1 had been performed in BS-3 labs, used for studying agents that can cause serious or lethal disease, but do not ordinarily spread among humans and have existing preventives or treatments.

A GAO 2009 report counted 400 accidents at BS-3 labs in the previous decade. Scientists argued that the H5N1 HPAI studies must be moved to BS-4 labs with one professor stating, "An escape would still produce the worst pandemic in history." Yet between 1978 and 1999, over 1,200 people acquired deadly microbes from BS-4 laboratories, the biosafety-4 level facilities that normally deal with infectious agents that have no known preventive measures or treatment.

Scandia National Laboratory's International Biological Threat Reduction program directed by Ren Salerno has a worldwide ongoing effort to prevent laboratory accidents, but there are varying standards for biosafety and at least 18 BS-4 labs outside of the US as of 2011.

So I'm still worried.

 

The "sex life" of a virus

Saturday, March 10th, 2012

The double helix

Most of us who are adults (and many who are not) have personal knowledge of human sexual reproduction, the process by which a man and a woman each contribute genetic material that contains DNA (deoxyribonucleic acid), the chemical basis of new life. DNA is an incredibly long twisted molecule. Its structure is a double helix with two strands composed of a sugar-phosphate backbone linked by four specific chemicals: adenine (A), thymine (T), cytosine (C) and guanine (G). These are called bases and match up in specific pairs, A always with T and G with C.

DNA has an amazing ability to replicate itself; the strands separate and each becomes the pattern for a duplicate to be constructed. Occasional mistakes are made, but we have a cleanup chemical, DNA polymerase, a kind of automatic spellchecker, that makes corrections.

Our human DNA has about 3 billion pairs of these bases; yours and mine and Cousin Flo's will be 99% identical. The remaining 1% is what makes the difference between an Einstein, a sports hero, a jazz musician and you and me. Our DNA is 98% the same as a chimpanzees and 85% the same as a mouse, but these comparisons clearly understate the importance a single base pair difference can make.

Viral "reproduction" is quite different. Influenza viruses don't have DNA; instead they contain RNA and have to replicate in living cells. Once they are inside one, the process results in many viral "offspring." These eventually leave to infect other cells in the organism and in doing so kill the one they replicated in. RNA (ribonucleic acid) is somewhat like DNA, but has one different base and a slightly different sugar in its "backbone." It's usually found as single strands shorter than those of DNA or, in the case of the flu virus, in seven or eight pieces. It lacks a proofreading enzyme so most of the new influenza virus copies are actually mutants.

Most of these changes, called antigenic drift, are minor. So the flu shot I get every year, which is an educated best guess as to what this years flu virus will be, offers considerable, but not total protection.

flu shots make sense

Sometimes the mutations are more significant; the process is called antigenic shift. That may occur when a host is infected with two different influenza viruses at the same time. The swine flu, for example, contained genes from pigs, humans and birds. When this happens, pandemics may occur.

Influenza is spread in several different ways: an infected person coughs or sneezes and you inhale the aerosolized virus; humans may come into direct contact with bird droppings or nasal secretions; various surfaces may become contaminated (viral particles in mucous may survive several weeks on banknotes).

Modern techniques for producing new flu vaccines rapidly may prevent millions of deaths and steps toward a "universal flu vaccine" are being researched. In the meantime logical precautions and yearly flu shots can save lives.

 

 

Viral diseases old and new: Let's just begin with the flu

Sunday, March 4th, 2012

A cause for alarm and action

Two days ago I began a post on zoonoses, diseases that spread from animals to humans. As usual, my interest led me from one fairly-limited topic to more-generalized subjects and I eventually decide to write a multi-post discussion of viral diseases that either have caused massive, widespread epidemics (AKA pandemics) or could potentially lead to them.

The number of deaths they have resulted in is staggering. HIV/AIDS has killed over 25 million of us in the past 30 years; the Black Plague over a 330-year period killed 75 million and smallpox is estimated to have caused over 300 million deaths over the centuries.

But let's start with influenza, the virus that we read about year after year as a worldwide threat. In the fall my wife and I get flu shots; we got used to doing so when we were both on active duty as Air Force medical staff personnel. It was routine; I didn't pay a lot of attention to what this year's shot contained and only vaguely kept up with anything written about the flu itself.

Then so-called "bird flu" came along and  the world geared up for a terrible pandemic.Usually the kind of influenza virus found in birds doesn't infect humans. But one unusual strain, called H5N1 (I'll explain what that means later) killed a six-year-old boy in Thailand in 2003. Of the people who caught this virus, 60 % died.

Most of us have heard about the Spanish flu, a major pandemic that infected a third of everyone living in 1918-1919 and caused 20 to 40 million deaths worldwide. Yet only 3% of those whom the virus infected died from it.

The so-called Asian flu pandemic in 1956-1958 causes 2 million deaths; the Hong Kong flu in 1968-1969 killed 1 million and the yearly seasonal flu results in anywhere from 5 to 15% of us getting ill; 250,000 to 500,000 die as a result. But these flu strains actually only resulted in a death ratio of less than 0.1%.

As it turned out, there was very little person to person spread of the avian flu. If there had been the results could have been catastrophic.

But the pigs had nothing to worry about; we did!

One of the outcomes of the avian H5N1 outbreak was fortuitous. When the "Swine flu" pandemic occurred in 2009-2010, the public health establishment and the medical community were considerably better prepared. The CDC summary is worth reading as it documents the steps taken to contain the virus; actually this was a flu strain that was transmitted from person to person and wasn't present in US pig herds.

The virus itself had genes from four different influenza virus sources, two from pigs, one from birds and one from a human flu virus. The CDC widely distributed kits to labs enabling them to identify the new viral strain. They and the World Health Organization (WHO) kept tabs on the numbers of cases of the new disease and WHO announced a global pandemic in June, 2009 .

A vaccine was developed with unusual speed and a preliminary target group of higher-risk individuals was identified; this consisted of 159 million people in the US. Vaccine safety was tested in various groups and the vaccine itself was administered starting in early October; by late December 2009 enough had been produced to allow vaccination of anyone wishing it.

The final results were impressive; less than two-thirds of a million people caught the virus and the death rate was 0.03%

 

 

Vindication? Part 1

Thursday, January 5th, 2012

One way to get lots of protein

Since the late 1990s when I invented a diet, or perhaps I should say an eating pattern, I've relied on one principal concept: Eat Less; Do More. I came upon this simple idea after listening to a group of medical professionals who were discussing which diet they should go on while they were simultaneously consuming huge portions at our hospital cafeteria.

One of them, I recalled, had tried a high-carb, low-protein diet the past year; losing nearly twenty pounds, then regained it all and more in a few months. Now she was going to attempt  to lose twenty-five pounds with a different approach, this one with an emphasis on protein. I had seen weight-loss plans come and go and didn't believe any of them were the answer, at least not for everyone. I remember coming home and saying to my wife, "Lynn, I've invented a new diet"

I explained it was simply, "Never finish anything; No snacks between (meals); Nothing after eight." I added, "Get lots of exercise."

I lost the seven pounds I had gained on a two-week vacation and didn't need my strategy again until early in 2009. Then I weighed 177 one morning, up three pounds from my normal weight since 1991. I attributed that to eating out four times in the prior week. But when I tried on a pair of good suit slacks, I realized the weight hadn't changed much, but the distribution sure had.

I went back to my eating plan, lost five pounds easily, then coasted a while before resuming the diet. Lynn bought me a digital scale and I weighed myself daily. I also started going to our gym six days a week. Eventually I shed thirty pounds and five inches off my waistline. At 147 pounds I was twenty-five under my usual high school weight. This morning, nearly two years later, I weighed 148.

I allow myself a three-pound zone of weight fluctuation, thinking that would account for fluid shifts and the occasional big splurge. Whenever I exceed 150 pounds I go back on my plan.

Then I read a Wall Street Journal article titled "New Ways Calories Can Add Up to Weight Gain: Study Challenges Idea That Varying Amounts Of Fat, Protein and Carbohydrates Are Key to Weight Loss." It quoted the Journal of the American Medical Association, AKA: JAMA. I went online and found the JAMA article and an accompanying editorial.

I read both pieces in detail, even finding a wild typo, "...their diets were returned to baseline energy levels and diet compositions (15% from protein, 35% from fat and 60% from carbohydrate)." I called the AMA and suggested they correct the numbers since they added to 110%.

Is a high-carb, low-protein diet safer?

But the basic premise of the study's data intrigued me. It's something I've believed for years, calories count, as opposed to what form those calories come in. But there's one extra facet: low-protein diets can be dangerous.

I'll analyze that in detail in my next post.

 

 

Slim down those truckers

Wednesday, November 23rd, 2011

some truckers are relatively slender

I have two series of posts going, but couldn't resist the article I found in the New York Times while riding a recumbent bike in the gym. The title alone, "A Hard Turn: Better Health on the Highway," was enough to grab my attention.

The first story was typical, a trucker driving long hours every day, eating all the wrong foods, getting no exercise, gaining huge amounts of weight. I found the online abstract of a 2007 Journal of the American Dietetic Association article cited: long-haul truckers of necessity eat at truck stops and of 92 such truckers stopping at a Mid-eastern US truck stop nearly 86% were overweight and 56.5% were obese.

One of our family members used to be a truck driver and I've heard his stories of long days spent behind the wheel, eating greasy foods when he stopped. He's slimmer now and in better shape as his current employment allows him more exercise time and a choice of where and what to eat.

Now that insurance costs are rising sharply, the trucking firms are getting involved and the truckers themselves, there's over three million of them in the US, are coming to grips with the issue out of necessity. One group ran a blood-pressure screening clinic for 2,000 truckers at a truck show. Twenty-one were immediately sent to a nearby emergency room; one had a heart attack before reaching the hospital.

drive carefully around trucks like this

Trucks are involved in 400,000 accidents a year and 5,000 fatalities. I just watched a nearly eighteen minute video on how we, as drivers of passenger vehicles, contribute to those accidents; 70% are caused by the drivers of other vehicles (see link below). Yet many of the ones caused by trucker driver error occur because the trucker has a health problem or falls asleep.

http://www.sharetheroadsafely.org/cardrivers/Unsafe-Driving-Acts.asp

Some truckers are taking steps to decrease their weight and its accompanying risks for themselves and those who share the roads with them. A number of companies are helping (and perhaps finding a lucrative new client group). I just looked at a website for "Rolling Strong," and found a gym in my area that offers fitness programs for truckers. Others are joining Weight Watchers, a solid organization that my slender wife has belonged to for many years (she says she was "chunky" in high school) or creating their own programs for fitness: one carries a fold-up bike in his 18-wheeler and uses it whenever he stops for a break. Many are cooking in their trucks or even hiring a trainer.

Others joined the Healthy Truckers Association of America, paying $7.50 a month to belong to an organization that is rapidly growing (see link below to Chicago tribune article). That group now offers truckers a prescription drug card enabling its members to save ~60% on meds.

http://healthytruck.org/node/101

I applaud all these moves; if I'm on the road with a large truck or a series of them, I'd like their drivers to be in shape and wide awake.

Early cholesterol testing now recommended

Saturday, November 12th, 2011

We're seeing more obese kids

With our sweeping epidemic of childhood obesity ( current estimates say over one-sixth of American kids are obese, three times the prevalence rate seen thirty years ago), it's time to take some additional steps. On Friday 11, 2011, sweeping new guidelines for childhood lipid testing were espoused by both the NIH's Nation Heart Lung and Blood Institute and The American Academy of Pediatrics. I found these, of all places, not on the websites of the two august bodies, but on the front page of the Wall Street Journal, an NPR article and in the Los Angeles Times.

The actual article in the journal Pediatrics, won't be out for two more days and should find a fair amount of opposition. Previous position papers by the AAP and the US Preventive Services Task Force have either suggested lipid studies be done in focused groups (eg. family history of heart disease or lipid disorders) or, if universally, no earlier than age 20. The CDC (actually the acronym has changed since it's now the Centers for Disease Control and Prevention), in a 2010 report, commented that a single elevated LDL cholesterol reading in a child may be found to be normal in subsequent testing.

The current recommendation panel, headed by Dr. Stephen R. Daniels, an MD, PhD who is Chairman of Pediatrics at the University of Colorado School of Medicine, is quick to avoid any suggestion of widespread statin use for children found to have high levels of "bad cholesterol," LDLs over 190 milligrams per deciliter. Another panel member, Dr. Elaine M. Urbana, director of preventive cardiology at the Cincinnati Children's Hospital Medical Center, was quoted as saying, "This documents on the fact that this generation may be the first to have a shorter life expectancy than their parents."

So go back to the facts: one-third of US kids are overweight and about 12.5 million of them are actually obese. Even here in Colorado, the thinnest state in the nation, I see some of those kids every day. We're not just talking about high schoolers; some of these fat kids are as young as two.

What's missing is a balanced diet with emphasis on fruits and vegetables and a reasonable amount of daily exercise.

earlier blood tests may let them live longer

Daniels comments, "...the atherosclerosis process really begins early in life." he also said, "Heart disease is the number one killer in our society...people who are able to maintain a low risk through childhood and early adulthood have a lower risk (of dying from coronary artery disease)."

From my perspective, it's our responsibility as parents and grandparents, to help prevent childhood obesity, the accompanying risk of later type 2 diabetes and the huge risk of early heart disease. I filled out a health history form yesterday and noted my mother had a heart attack at age 74 (she lived 'till 90), but ignored my father's need for an artery unclogging procedure shortly before his 90th birthday. That may be something I can put off by eating well and exercising, but that's not the focus here.

I never want to see a child or grandchild die of a heart attack in their 50s or 40s or 30s or 20s.

So blood tests between ages 9 and 11 and again between 17 and 21 make sense.

 

 

Should the kids be in the middle? It may depend on the kid's middle

Tuesday, November 1st, 2011

This is not the example you should set

Wall Street Journal headline caught my eye, "Obesity Fuels Custody Fights." It noted that childhood obesity is frequently being used by one parent or the other as grounds for custody changes with accusations concerning poor diets and lack of exercise flying back and forth.

That led me to a July 13, 201 article in The Journal of the American Medical Association (henceforth JAMA), "State Intervention in Life-Threatening Childhood Obesity."

We're not talking about mildly overweight kids here; in 2009 a 555-pound fourteen-yer-old boy, living in one of the southeastern states, was taken  by court order from his mother and placed into foster care. She in turn was charged with criminal neglect as the Department of Social Services for that state felt they must intervene or the boy would be at considerable risk for major obesity-related problems, especially diabetes type 2. I found a photo online of the boy and my jaw dropped.

The JAMA article notes "even relatively mild parenting deficiencies" can contribute to a child's weight problems: having junk food in the home, frequently taking the kids to fast food restaurants, failing to model an active lifestyle.The CDC estimates `17% of America's kids and teens are obese (we're not just talking mildly overweight); that's 12.5 million kids at risk. The two Boston authors who wrote in JAMA quote a study showing 2 million of those obese kids are grossly obese with a BMI at or beyond the 99th percentile for their age (a very small percentage of those grossly obese kids, it turns out, may have a genetic abnormality; in those rare cases, the parents aren't to blame).

What can we do about this horrendous problem? Well, there are a variety of "bariatric" operations available in pediatric surgery programs; in dire cases state legal action may be

this makes more sense

necessary. But I liked what I saw the other day walking Yoda, our nine-year-old Tibetan terrier, on his morning constitutional (he gets an evening walk as well, which means either my wife or I or both get some extra exercise).

We came near the elementary school near us and there was a long line of kids, punctuated by an occasional teacher, running past. We stopped to watch, realized these were kindergarden and/or first grade kids, and finally had an opportunity to ask one of the teachers what was going on.

"It's a new program we've started in the Poudre School District," she said. "We keep the kids moving for thirty minutes. They can run and most do, or twirl around and walk the field next to the school, but they've got to keep moving."

The conclusion in the JAMA article was stark, but offered a road to resolution. The authors noted, "An increasing proportion of US children are so severely obese as to be at immediate risk for life-threatening complication including type 2 diabetes." They mentioned the pediatric weight loss surgical programs and state protective services, but finished with our need to decrease the need for those options through beefing up the social infrastructure and policies to improve both kids' diets and guide them toward more physical activity.

Those solutions may work.

Listeria

Friday, October 14th, 2011

The culprits, this time.

Reading "USA Today" online, I found an article detailing the repercussions of the recent/ongoing outbreak of disease linked to cantaloupes coming from one specific farm in Colorado. That operation, Jensen Farms, re-called its fruit in mid-September. The Food and Drug Administration and the Seattle-based Institute for Environmental Health have not yet found the root cause of the outbreak. Since the normal shelf life for cantaloupe is ~two weeks, none of the Jensen Farm product should still be in stores. And no other sources have been implicated. Nonetheless, cantaloupe producers in California and Arizona, the two states with the largest crops of this fruit, are seeing sales plummet 80% or more.

That probably shouldn't surprise us. Spinach sales, devastated by the 2006 E. coli outbreak, are still down nearly a third in one California county.

As of October 12, the current outbreak had led to 116 illnesses and 23 deaths, making it the deadliest in more than a quarter century. There was another outbreak in Texas in October of 2010; that one was related to celery and resulted in 10 total illnesses and five deaths.

I went to several online medical sites to refresh my memory on Listeriosis. When I dealt with infections from this bacteria it was in immuno-compromised patients. Listeria is found worldwide, often in association with farm animals, many of which are otherwise healthy carriers of the bacterium. People can also be carriers and perhaps five to ten percent of us have Listeria in our bowel flora.

There are roughly 2,500 US cases of Listeria infections yearly and about a fifth of those infected die. Most are isolated cases, not major outbreaks The bacteria isn't transferred from person to person with the exception of pregnant women and their fetuses or newborn babies.

This is a foodborne illness, most commonly associated with improperly processed deli meats or unpasteurized milk products.

About 30% of all reported US cases occur in pregnant women. As opposed to the majority of us, who may have nonspecific symptoms, or none at all, pregnant women can transmit the infection to their fetuses or to their newborn infants. They also may have minor symptoms, if they are otherwise healthy, but Listeria can lead to miscarriages, stillbirth, premature birth or, potentially, to serious disease or death of newborn babies.

Others at higher risk for serious disease when infected with this bacterium include the elderly, diabetics, cancer patient, AIDS patient, those with significant kidney disease and anyone on immunosuppressive drugs.

It's tough to diagnose Listeria infections: the most common signs and symptoms include fever, muscle aches, nausea and/or diarrhea. There are no reliable tests for the bacteria, so the diagnosis is difficult in the absence of a history of exposure to a potentially contaminated food source during an outbreak.

Most of us clear the infection without any treatment; those at higher risk should be considered for immediate IV antibiotics and consultation with an Infectious Disease specialist is recommended (and if a pregnant woman has the inception, an Ob-Gyn specialist and a Pediatrician should be involved.