Infected Workers Pose Risk to Patients, Colleagues
By David Mitchell
At least 81 health care workers across the country have confirmed or probable cases of novel influenza A (H1N1), evidence that some workers are not following CDC guidance for personal protection from infectious disease.
Michael Bell, M.D., associate director for infection control in CDC's Division of Healthcare and Quality Promotion, said in a June 18 news conference that health care workers should use fit-tested respirators, gloves and eye protection when caring for a patient with probable H1N1 infection.
He also said that such patients should be placed in single-patient rooms to reduce the risk of transmission, and they should be instructed about proper respiratory hygiene and cough etiquette. Good hand-washing hygiene also is a standard precaution.
Aerosol-generating procedures should be performed in rooms with negative-pressure air handling to prevent spread to other parts of the facility, said Bell. And it is critical that infectious patients be identified "at the front door" in order to protect health care workers and other patients.
The CDC said in its June 19 Morbidity and Mortality Weekly Report or MMWR, that as of May 13, the agency had received reports of 48 confirmed or probable cases of health care workers infected with H1N1 in 18 states. Since that date, however, additional cases have since been reported and are under review, according to Bell.
Of the original 48 cases, CDC has detailed information for 26 patients, half of whom were deemed to have contracted the infection in a health care setting. Of those, 12 were possibly or probably infected through contact with an ill patient, and one case involved worker-to-worker transmission. Of the 26 cases, two workers were hospitalized; neither died.
Bell said that in the more recently reported cases, proportionately more instances of worker-to-worker transmission occurred.
"I think it's very important that health care personnel understand that if they're ill, especially during an epidemic of influenza like this, they need to stay home," said Bell, adding that health care facilities should have appropriate leave policies in place and ensure employees know they won't be penalized for using sick leave.
None of the 12 workers infected by ill patients reported adhering to all recommended infection control practices. Only five reported always using gloves, three used either a mask or respirator, and none used eye protection. The one physician who did use a respirator had not been fit-tested for the equipment.
INFECTION CONTINUES TO SPREAD
CDC officials said June 19 that there were 21,449 confirmed and probable H1N1 infections in the United States, with 87 confirmed deaths. The World Health Organization said June 19 there were 44,287 laboratory-confirmed cases worldwide, with 180 deaths.
Although CDC reports show that overall influenza activity in the United States decreased the week of June 7, with nine out of 10 surveillance regions reporting flu activity below baseline, Daniel Jernigan, M.D., Ph.D., deputy director of the CDC's Influenza Division, said during the June 18 CDC news conference there likely have been "hundreds of thousands" of cases in the United States, and the virus is expected to continue to spread here through the summer.
He added that the CDC is monitoring how the virus behaves during the flu season now going on in the Southern Hemisphere in preparation for the fall flu season in North America.
CDC ISSUES GUIDANCE FOR SUMMER CAMPS
Children have been among those most seriously affected by the H1N1 virus, and Jernigan said it was no surprise that outbreaks have been reported at summer camps in multiple states. Accordingly, the CDC has issued guidance for camps and parents of campers.
Briefly, the agency recommends that people who have had influenza-like symptoms within the past seven days should not attend, work or volunteer in a camp until at least seven days after their symptoms began or until they have been symptom-free for 24 hours.
Camp staff, volunteers and campers should be able to recognize flu symptoms -- in themselves or others -- and report them to staff. Ill campers and staff should be isolated and treated.
Among other highlights in the CDC recommendations:
Parents should plan ahead for the possibility that their child could become ill while at camp. Camps should communicate with local public health authorities to develop plans for addressing potential outbreaks. Hand-washing facilities should be readily available to campers and staff, and they should be reminded to use good hand and respiratory hygiene.
People 18 or younger with a confirmed or suspected case of influenza should not be given aspirin or aspirin-containing products because of the risk of Reye’s syndrome.
CDC URGES USE OF PNEUMOCOCCAL VACCINE
Finally, the CDC also has issued guidance for use of the 23-valent pneumococcal polysaccharide vaccine, or PPSV23, during the outbreak. CDC officials are drawing attention to the agency's existing recommendations that all people ages 65 and older and those ages 2-64 years who have certain high-risk conditions receive a single dose of PPSV23 because people in these groups are at increased risk for both pneumococcal disease and serious complications from influenza.
Those high-risk conditions are:
chronic cardiovascular disease,
chronic pulmonary disease,
chronic liver disease,
cerebrospinal fluid leaks,
functional or anatomic asplenia, and
Other high-risk patients indicated for PPSV23 vaccination are those ages 19-64 who smoke cigarettes or have asthma.
Infected Workers Pose Risk to Patients, Colleagues
The H1N1 virus is spreading in distinct regions of the globe. But the WHO says the pandemic is only 'moderate in severity' and cautions against overreaction by the public.
By Thomas H. Maugh II / Los Angeles Times
9:06 AM PDT, June 11, 2009
The World Health Organization this morning acknowledged what many health experts have been saying for weeks: The outbreak of novel H1N1 virus is now a pandemic.
In a letter sent to its member countries, the WHO said it is officially raising its infectious diseases alert to Phase 6, its highest level, in recognition of the fact that the virus is now undergoing communitywide transmission in Australia as well as in North America. Such spread in two distinct regions of the world is the primary criterion for raising the alert level.
But the agency said that the pandemic is only "moderate in severity" and cautioned against overreactions to the increased alert level.
The announcement marks the advent of the first global influenza epidemic in 41 years. The last one was the Hong Kong flu epidemic of 1968, which killed an estimated 1 million people worldwide.
So far, the H1N1 or swine flu pandemic this year has accounted for 27,737 laboratory-confirmed cases and 141 deaths, although health officials believe many times that number have been infected but have not been tested because their disease was mild.
A normal seasonal flu outbreak kills about 250,000 to 500,000 people worldwide.
In most industrialized countries, the rise in the alert level will have little practical effect because health authorities were already behaving as though a pandemic had been declared. In the United States, where there have been more than 13,000 cases and at least 27 deaths, "Our actions in the past month have been as if there was a pandemic in this country," said Glen Nowak, a spokesman for the Centers for Disease Control and Prevention.
But it will accelerate the production of a vaccine against the new virus. Several countries have signed contracts for the vaccine with manufacturers that call for its production if a pandemic is declared. Most of them have received so-called seed stock viruses from the CDC in the past two weeks, allowing them to begin the lengthy process of growing the virus in eggs and producing vaccines. But it will still take a minimum of four to six months for the vaccines to be available for use.
The announcement will have more impact on Third World countries, freeing up additional funds for treatment and prevention and helping to make stocks of antiviral drugs more readily available.
The WHO has hesitated to raise the alert level for fear that such an announcement would be misconstrued as an indication that the virus has become more pathogenic. WHO spokesman Gregory Hartl emphasized today that "Phase 6 doesn't mean anything concerning severity, it is concerning global spread. . . . Pandemic means global, but it doesn't have any connotation of severity or mildness."
In fact, he said, all evidence to date is overwhelming that the virus is mild in its effects. Experts fear, however, that as it passes through populations, it could mutate to become more lethal and return with increased force in the winter influenza season. That is what happened with the Spanish flu pandemic of 1918.
Officials had said they feared that the announcement would lead frightened people who are not really sick to overrun hospital emergency rooms, impairing the healthcare system's ability to treat the truly sick. That has happened in past outbreaks, and there is already some evidence that it is happening in South America, particularly in Chile, where the numbers of infected have been growing.
Dr. Keiji Fukuda, assistant director general of the WHO, also said earlier this week that he fears imposition of travel restrictions, border closing and bans on food imports -- all of which have already happened in the earlier stages of the outbreak.
by Michael Cover
As we learn more about the evolving situation with regard the new strain of influenza circulating around the world, it is useful to look to our past experiences with pandemic influenza to learn and apply any lessons that can help mitigate morbidity and mortality.
Let’s call this a tale of two cities … in the 1918 Spanish Influenza epidemic, a minimum of 50 million people around the world died from the flu or from secondary infection. But not all localities experienced the same death rate, largely due to the public health guidance that was followed in that specific area. In the US, St. Louis and Philadelphia had vastly different outcomes, despite the fact that the same strain of influenza infected their communities.
In 1918, there were no influenza vaccines or antivirals and limited international travel. The public health responses were limited to isolating the ill, quarantining houses, closing schools, canceling worship services, restricting the size of funerals and weddings, closing saloons and theaters, restricting door-to-door sales, discouraging the use of public transportation, staggering the hours of business and factory operations, imposing curfews and, in some places, recommending the use of face masks in public.
By the time officials in Philadelphia determined they had a real public health threat, it was already too late. Influenza was rampaging through the city, in most part because city leaders had not followed public health guidance. They did not close schools and movie theaters in time. They succumbed to federal pressure to sell war bonds and allowed large public gatherings, including a citywide parade in support of war bond sales. The result was that in 16 weeks, more than 12,000 Philadelphians died, an excess death rate of 719 people for every 100,000 inhabitants.
The story in St. Louis was quite different. Two weeks before Philadelphia officials began to take action, physicians persuaded the city to require that flu patients register with the health department. Two days after the first cases of influenza, police helped enforce a shutdown of schools, churches and other gathering places. Public health guidance was issued on coughing, spitting, sneezing and other forms of transmission. The result? Excess deaths in St. Louis were 347 per 100,000 people, less than half the rate in Philadelphia. Early action saved thousands of lives.
In a 2007 statement, Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases noted the importance of early intervention. “A primary lesson of the 1918 influenza pandemic is that it is critical to intervene early,” he said. “While researchers are working very hard to develop pandemic influenza vaccines and increase the speed with which they can be made, nonpharmaceutical interventions may buy valuable time at the beginning of a pandemic while a targeted vaccine is being produced.”
We do not yet know how severe this influenza infection will become. But we live in a very different world than our grandparents and great grand parents did in 1918. We have the capacity for vaccine development and production. We have access to antivirals and medical care. We know more about how to fight viral infections and secondary bacterial infections. But the best way to fight influenza may be by sticking to the simple, time tested methods.
So what are they? Simple. Follow the public health guidance from the CDC and other health institutions. Heck, follow the advice your mom probably gave you: know proper cough and sneeze hygiene. Wash your hands often. If you’re sick, stay home. For more information, go to http://www.pandemicflu.gov/
From University of Pittsburgh Medical Center
By Matthew Watson, August 4, 2008
The August issue of Emerging Infectious Diseases (EID) includes two articles on the impact and implications of bacterial co-infection, and resulting pneumonia in influenza patients, during a pandemic.
Authored by Dr. John Brundage and Dr. Dennis Shanks, the first article is a retrospective epidemiological review that analyzes the unusual nature and severity of the 1918–19 influenza pandemic.1 Dr. Brundage’s claim is that the high case fatality rates seen during that pandemic were not due, as some historians have claimed, to primary pneumonia caused by a hypervirulant strain of the influenza virus. Rather, he maintains that many of the deaths that occurred during the 1918 pandemic resulted from co-infection and subsequent pneumonia caused by common respiratory bacteria.
The second article, authored by Gupta, et al., identifies bacterial pneumonia as a likely source of mortality during a pandemic and offers recommendations for addressing gaps in medical pandemic preparedness. While acknowledging the scarcity of recent data regarding the incidence of bacterial co-infection during a pandemic, Gupta notes that “secondary bacterial infection is a common cause of death in persons with seasonal influenza; co-infections have been found with ≈25% of all influenza related deaths.”2
Both Brundage and Gupta agree that the pathogens most likely to cause respiratory disease are Streptococcus pneumoniae, Staphyloccus aureus (both methicillin sensitive and resistant3) and Haemophilus influenza. Accordingly, the use of antimicrobial medications effective against these pathogens will be indicated—for either treatment or prophylaxis. However, due to the use of “just in time” supply chains, pharmaceutical shortages are likely. Consequently, both authors recommend that hospitals work with suppliers on stockpiling efforts in order to mitigate shortages.
The two papers also generally agree on the following recommendations aimed at reduction of mortality due to bacterial pneumonia for influenza patients in a pandemic:
To the extent possible, make vaccination against S. pneumoniae a priority prior to a pandemic event.
Once a pandemic has begun, vaccinate communities that are still unaffected with a strain-specific influenza vaccine, if available.
During a pandemic, isolate patients with symptomatic respiratory disease as much as possible.
Conduct surveillance to track pandemic-related bacterial infections and emerging antimicrobial resistance.
Conduct further research into bacterial pneumonias that occur secondary to influenza infection.
Brundage JF, Shanks GD. Deaths from bacterial pneumonia during 1918-19 influenza pandemic. Emerg Infect Dis. 2008;14:1193-1199. http://www.cdc.gov/eid/content/14/8/pdfs/07-1313.pdf. Accessed July 24 2008.
Gupta RK, George R, Nguyen-Van-Tam JS. Bacterial pneumonia and pandemic influenza planning. Emerg Infect Dis. 2008;14:1187-1192. http://www.cdc.gov/eid/content/14/8/1187.htm. Accessed July 24 2008.
The Centers for Disease Control and Prevention. Severe methicillin-resistant Staphylococcus aureus community-acquired pneumonia associated with influenza—Louisiana and Georgia, December 2006–January 2007. MMWR. 2007;56:325-9. http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5614a1.htm?s_cid=mm5614a1_e. Accessed July 24, 2008.
June 3, 2009
Statement of Worldwatch Senior Researcher Danielle Nierenberg to Mexican Congress
Washington, D.C.-As health officials scramble to develop a vaccine for the H1N1 virus, commonly referred to as swine flu, there is reason to believe that the current swell is merely a sign of the larger pandemic to come. We should regard the current outbreak of H1N1 as a bad dress rehearsal for opening night. It is not a question of whether the virus will reemerge, but when, and we are woefully unprepared.
Influenza pandemics are often preceded by "herald waves" of a flu strain at the end of one flu season, only to return stronger the next flu season, according to the U.S. Centers for Disease Control. This was true of the 1918 pandemic, which first emerged as a moderate flu virus in the spring and returned much stronger in the fall, killing as many as 40 million people worldwide. While much has changed since then, this new strain poses new challenges and we are not prepared to handle the consequences of quarantining and treating people who are infected or limiting global air travel and international trade.
Rather than focusing all of our attention on developing a vaccine, we must find ways to stop these diseases before they start. Prevention of zoonotic diseases-diseases that animals can transfer to humans-requires a fundamental change in the way we raise animals. We can begin by raising fewer animals for food overall and phasing out the most intensive confinement practices.
While the connection between the Granjas Carroll industrial pig operation in Vera Cruz, Mexico (a Smithfield Foods subsidiary) and the emergence of H1N1 is circumstantial, there is some evidence to suggest that factory farming practices are to blame. Crowded conditions and the genetic uniformity of animals on factory farms make them ideal incubators for disease. Furthermore, the overuse and misuse of antibiotics to combat these diseases create multidrug-resistant bacteria, making it harder to fight illness among animals and humans alike.
As we raise more animals in industrial-style operations, confining them by the tens of thousands, it is likely that we will see other diseases emerging and jumping the species barrier from animals to humans. Because of their genetic similarity to humans, pigs and chickens often serve as "mixing vessels" for various diseases, stirring up their genetic traits and making them easier to pass along.
As we brace for the next wave of the swine flu pandemic, perhaps we will all become more aware of the conditions under which more than 40 percent of the world's nearly 1 billion pigs are raised. Ultimately, we must realize that how we raise animals for food is inherently linked to our own health and the health of our environment.
This statement is based on remarks Danielle Nierenberg will deliver to members of the Mexican Congress on June 3, 2009.
Thu Jun 11, 2009 8:31am EDT
By Stephanie Nebehay
GENEVA, June 11 (Reuters) - The World Health Organisation was poised on Thursday to declare that the new H1N1 virus has caused the first influenza pandemic in more than 40 years, health sources said on Thursday.
The move will trigger heightened health measures in the WHO's 193 member states as authorities brace for the worldwide spread of the virus that has so far caused mainly mild illness.
WHO Director-General Dr Margaret Chan was to hold a news conference on the outbreak at 1600 GMT. Flu experts advising Chan, who met earlier on Thursday, were expected to recommend moving to the top phase 6 on the WHO's six-point scale, the sources said.
That would reflect the fact that the disease, widely known as swine flu, was spreading geographically, but not necessarily indicate how virulent it is.
"Phase 6, if we call a phase 6, doesn't mean anything concerning severity, it is concerning geographic spread ... Pandemic means global, but it doesn't have any connotation of severity or mildness," WHO spokesman Gregory Hartl said.
"In fact, what we are seeing with this virus so far is overwhelmingly to date mild disease. So we would think that this event is really a moderate event for the time being, because the numbers are high but the disease is overwhelmingly mild," he told Reuters Television before the talks.
David Heymann, a former top WHO official now chairing Britain's Health Protection Agency, said that countries had tried to contain the virus through measures including school closures during the current phase 5. This has extended the precious time needed to prepare for a full-blown pandemic.
"During phase 5, the government and people in the U.K. have had the time to prepare for a pandemic -- this has hopefully decreased any surprise and concern that might be associated with a WHO announcement of phase 6, if one is made," he told Reuters.
As it spreads in humans, science cannot predict what course the virus will take, the disease it causes and the age groups infected, Heymann said. "The severity of that disease, the effectiveness of antiviral drugs and the stability of the virus must all be watched closely," he added.
A pandemic could cause enormous disruption to business as workers stay home because they are sick or to look after family members and authorities restrict gatherings of large numbers of people or movement of people or goods.
World markets shrugged off the possibility of a pandemic, as investors focused on possible global economic recovery.
AUSTRALIA LIKELY TRIGGER
Widespread transmission of the virus in Victoria, Australia, signalling that it is entrenched in another region besides North America, is likely to be the trigger for moving to phase 6.
Five people have been admitted to intensive care in Australia and more than 1,000 cases confirmed following widespread testing in the state. [ID:nSYD482995]
"We have tested 5,500 people in the last two weeks, that is more people than we test in our whole influenza season," said Victorian state premier John Brumby.
One health source, who declined to be named, said the experts were also expected to recommend finishing production currently under way of seasonal flu vaccine for the northern hemisphere next winter.
"They might say finish seasonal vaccine and say begin pandemic vaccine as soon as it is feasible," he said.
Drugmakers have obtained the new influenza A (H1N1) seed virus in the past two weeks, enabling them to begin the production process by growing the virus in eggs. [ID:nLA644931]
Company officials said on Wednesday that they were on track to have a vaccine against the new strain ready for the northern hemisphere autumn.
Seasonal flu each year kills up to half a million people, mainly elderly, and causes severe illness in millions, so a premature switch in vaccine production to cope with the new strain could put many people at risk.
The new strain can be treated by antiviral drugs oseltamivir, the generic name of Roche Holding's Tamiflu tablets, and Relenza, a spray made by GlaxoSmithKline.
The strain, which emerged in April in Mexico and the United States, has spread widely in nations including Australia, Britain, Chile and Japan.
Authorities in Germany have confirmed 27 cases of H1N1 at a school in the industrial Rhineland city of Duesseldorf, the most concentrated outbreak of the virus so far in Europe's biggest economy. [ID:nLB407116]
There have been 27,737 infections reported in 74 countries to date, including 141 deaths, according to the WHO's latest tally of laboratory confirmed cases, but the real number of people with the disease is likely to run into at least hundreds of thousands, as mild cases may not have been detected. (For more Reuters swine flu coverage, please go to: here ) (For WHO information on swine flu, go to: here ) (Additional reporting by Anne Richardson and Vincent Fribault in Geneva, Dave Graham in Berlin and Michael Perry in Sydney) (Editing by Jonathan Lynn and Richard Balmforth)
by Peter Collignon / Brisbane Times
May 29, 2009
IN THE past century we had three influenza pandemics. The worst was Spanish flu (1918-19), when tens of millions of people died.
The swine flu strain lacks one of the two essential characteristics needed to cause that kind of disaster. It readily spreads from person to person but it does not have a more aggressive (or virulent) effect in people compared to the winter flu strains.
The swine flu strain is not hyper-virulent. In the US, for every 1000 people who get infected, about 40 need to be admitted to hospital and one dies. Still aggressive, this virus is less so than many of the flu viruses that change slightly every year or so, and then circulate and cause epidemics (or pandemics) around the world, principally in winter.
This swine flu strain is an H1 strain. Variations of H1 strains have recirculated in people since 1918, and thus many may have some immunity already. This is reflected in the relatively low infection in people aged over 30. Even in children and young adults, with presumably little or no immunity, there does not seem to be excessive mortality compared to seasonal influenza. Again this reflects the relatively low virulence.
We need to consider what killed most people when new and virulent flu strains spread. It was bacteria, not the direct effect of the flu virus. Secondary bacterial infections, especially with pneumococcus and staph, caused nearly all deaths.
In 1918-19 there were no antibiotics. In the late 1950s when Asian flu struck, many deaths occurred because penicillin was the only antibiotic widely available and most strains of golden staph had developed resistance. Antibiotic resistance is a rapidly growing global problem.
Yet in Australia we still have a variety of antibiotics (especially injectables) that will work against nearly all strains of bacteria that might cause pneumonia.
Good hygiene can slow or stop the spread of flu virus. This means using alcohol hand rub and soap and water, masks and other general infection control measures, such as staying home if you are unwell.
We need to reconsider how we approach this virus. Flu strains every year cause proportionately more illness and deaths than this swine flu strain. Stricter controls will be necessary only when a new influenza arrives that is hyper-virulent and spreads easily.
Peter Collignon, an infectious diseases physician and microbiologist, is professor, school of clinical medicine, Australian National University.
Experts wrangle over effects of antibiotics use in livestock
by Michael Schroeder and Jenni GlennThe Journal Gazette
Dr. Tim Barman, director of veterinary services for Cooper Farms in Ohio, prescribes antibiotics to keep disease outbreaks among 12,000 baby turkeys from getting “bigger and bigger.”
Farms often use antibiotics to promote growth in livestock, which health groups say contributes to drug-resistant bacteria in people. Baby turkeys are sectioned off in pens at Cooper Farms. A benefit of using antibiotics to treat illness rather than promote growth, Barman said, is that healthy animals grow faster.
The bacteria: Methicillin-resistant Staphylococcus aureus, or MRSA, is a type of bacteria that’s resistant to certain antibiotics such as methicillin, oxacillin, penicillin and amoxicillin. Common in nature, MRSA can exist on the bodies of humans and animals – on the skin, in the nose – without causing damage.
Deaths: In cases where MRSA enters the body, such as through a wound, it can lead to serious infections. MRSA is responsible for an estimated 94,000 serious MRSA infections and 19,000 deaths in the U.S. annually.
Signs and symptoms: Most staph infections, including those caused by MRSA, appear as a bump or infected area on the skin that may be red, swollen, painful, warm to the touch, perhaps draining. The symptoms may also include a fever.
MRSA strains: MRSA infections usually fall into one of two categories: hospital-acquired or community-acquired. When MRSA was discovered, people typically contracted it at hospitals and health clinics. In the past two decades, however, the number of MRSA infections in people who have had no connection to any health care setting has increased. But hospital-acquired MRSA still makes up the bulk of known MRSA infections.
The strain of MRSA that is regularly isolated from livestock, often referred to as ST398, is different from the strains responsible for hospital-acquired and community-acquired MRSA.
Livestock and MRSA: A Denmark study several years ago identified MRSA in both swine and people who worked with swine. Those who worked with the infected pigs were more likely to be infected than those who didn’t. MRSA has also been isolated in cattle and poultry. But the exact relationship between resistance to certain antibiotics used in livestock, such as pencillin G, and resistant bacteria infecting people is unclear and the subject of considerable debate among health and farm officials.
The Preservation of Antibiotics for Medical Treatment Act of 2009 was introduced and referred to the House Committee on Energy and Commerce and Rules Committee on March 17. It hasn’t moved since that day.
The debate on the use of antibiotics in farm animals is decades old. Similar legislation has failed to gain traction. Fort Wayne – In the wake of an international flu outbreak, pigs have been unfairly vilified.
The so-called swine flu, which now appears more benign than first thought, is typically passed from person to person, not pig to person.
But the new flu strain, a mix of human, pig and bird flu strains, is a reminder that people and animals share much, including disease and infection.
More than 350,000 people call Allen County home, and even the healthiest are susceptible to the flu and other ailments. And humans are not the only potential germ carriers here.
In addition to pets such as cats and dogs, about 13,400 cattle, 36,700 hogs and 2,400 egg-laying chickens are kept here, according to U.S. Department of Agriculture figures.
The implications of that aren’t lost on health organizations such as the American Medical Association, which supports federal legislation to restrict the use of antibiotics in livestock primarily for treating disease.
Proponents of the legislation say rampant antibiotic use contributes to the spread of antibiotic-resistant bacteria in people. Such bacteria include MRSA, or methicillin-resistant Staphylococcus aureus.
MRSA is responsible for an estimated 94,000 serious infections and 19,000 deaths in the U.S. annually, according to a 2007 report by the Centers for Disease Control and Prevention.
But industry officials and other opponents say banning certain antibiotics used in livestock in the U.S. – something already done in Europe – could have unintended consequences, such as driving up food costs and endangering public health.
Why it matters
Experts on both sides of the debate say people’s health – not just animals’ – could be affected by antibiotic use in livestock. The overuse of antibiotics, sometimes to help animals gain weight, could cause problems. But so could underuse.
Frequent use of antibiotics makes it easier for bacteria to build resistance to drugs. Some resistant bacteria can be passed between animals and people, but the extent to which people become infected because of resistance built up in livestock is unclear.
People-to-people transmission is blamed for most MRSA infections. Still, Dr. Deborah McMahan, Allen County health commissioner, says it’s important to use antibiotics responsibly in people and animals. Doctors are getting better about not using antibiotics unnecessarily in people, McMahan said, but there’s room for improvement.
MRSA is a complex problem, she said; it demands an approach that considers all potential contributors – major and minor. But without more data, McMahan isn’t sure how antibiotic use in a rural Allen County farm affects someone in downtown Fort Wayne.
Marianne Ash, a trained veterinarian, is director of biosecurity and preparedness planner for the Indiana State Board of Animal Health. Ash said "very, very few" human MRSA infections are of the animal strain. The issue, if it could be called that, isn’t even on the board’s radar, officials there said.
Based on current science, Ash doesn’t believe a ban on using antibiotics for growth promotion is warranted.
Veterinarians are more likely to be MRSA carriers than the general population. The same is true of doctors who treat people. Only when the drug-resistant staph infects a person, perhaps entering through an open wound, does it cause problems.
But Ash said pets are more likely to spread MRSA to people than farm animals.
"The real issue is with companion animals rather than livestock," she said.
Antibiotics keep livestock healthy and free of pathogens that could wind up in the food supply and cause food poisoning, said Ron Phillips of the Animal Health Institute, a trade association representing pet and livestock pharmaceutical manufacturers. Without these tools, farmers would have limited ways to treat illnesses in their herds and flocks.
Without antibiotics, Adams County farmer Ben Rediger estimates 30 percent of the 900 young dairy cows he raises would die. He uses the antibiotics to treat cows for respiratory illnesses, diarrhea or infections.
"They get sick just like people," he said.
Rediger said he uses the expensive medications sparingly. He watches for signs that a heifer isn’t feeling well and then administers antibiotics.
Those favoring limits on antibiotic use wish all farmers would be so particular.
But others advocate more widespread use of antibiotics. They say low doses of antibiotics keep animals healthy and reduce the risk of food poisoning for people.
Risks of antibiotics
Antibiotic resistance increases almost every time a drug is prescribed, regardless of whether the patient is a person or an animal, said Paul Ebner, an assistant professor of animal sciences at Purdue University. But Ebner said it is difficult to trace the origins of human antibiotic-resistant illnesses, partly because people overuse many medications.
Studies are examining whether antibiotic use on farms affects human health. But the American Medical Association isn’t waiting to push for limits.
The association opposes farmers using low-dose antibiotics as pesticides or growth promoters. Proposed legislation would require those wanting to use new animal drugs for purposes such as growth promotion to first demonstrate that the antibiotics won’t harm people.
The effectiveness of antibiotics "is being compromised by bacterial resistance, arising in part from the excessive use of antibiotics in animal agriculture," the association said in a letter supporting proposed legislation.
A strain of MRSA recently found in pigs and pig farmers in Illinois and Iowa is the same strain found in one-fifth of all documented human cases in the Netherlands.
The strain, sequence type 398, or ST398, hasn’t proved prevalent in the U.S. But its discovery here raises questions about the potential role of livestock in the spread of MRSA among people.
The study published in January in the online Public Library of Science journal was the first to document MRSA in swine and swine workers in the U.S. As far as the researchers knew, it was also the first to report the presence of the ST398 strain in the U.S.
The findings suggested that "agricultural animals could become an important reservoir for this bacterium," according to lead study author Tara Smith, an assistant professor of epidemiology at the University of Iowa, and other researchers.
But because similar antibiotic protocols were in place at all farms studied, the study’s authors said they couldn’t speculate on the relationship between antibiotic use in the pigs and MRSA.
How much is used
Various organizations – some defending antibiotic use and some concerned about it – estimate that between 30 percent and 70 percent of all antibiotics are used on farms, said Bob Martin, former executive director of the Pew Commission on Industrial Farm Animal Production.
The Animal Health Institute, a trade industry for animal medication manufacturers, uses the 30 percent figure. The Union of Concerned Scientists, which supports restrictions on nonessential livestock antibiotics, uses the 70 percent figure.
Phillips, of the Animal Health Institute, said pet and livestock owners spend about $5 billion a year on antibiotics, vaccines and other medicines.
In 2005, 24.4 million pounds of antibiotics were sold for use in livestock and pets, according to the Animal Health Institute. Most livestock antibiotics are used to treat diseases, but in 2007 about 13 percent were used to help animals grow faster. That use has drawn criticism from health organizations.
USDA figures show antibiotics might be used more widely for growth promotion than farmers care to admit. About 55 percent of hog farms feed antimicrobials – drugs to fight bacteria or viruses – to hogs that have been weaned from their mother’s milk, according to a 2006 agency survey of hog farmers.
Nearly 18 percent of dairy farms feed weaned dairy cows antimicrobials for disease prevention or growth promotion, the USDA found in a 2002 survey.
The agency did not have figures for beef cattle or poultry operations.
Denmark banned growth-promoting antibiotics a decade ago, and opponents of antibiotic limits point to an increase in sick animals that needed antibiotic treatments. They say current farm practices would be more effective than a ban.
A ban in the Netherlands had similar results.
A 2002 World Health Organization report found the Danish ban was associated with slower growth and an increase in death and diarrhea in weaned pigs, but the changes weren’t seen in the older pigs.
The organization also said the ban could have indirectly increased salmonella resistance to the drug tetracycline. After the ban, farmers used the drug more often to treat sick animals. An increased resistance could lead to more human salmonella infections.
But the World Health Organization said the Danish ban produced "no serious negative effects." It found no reason why, under similar conditions, other countries couldn’t discontinue the use of antibiotics solely for growth promotion. In 2006, Europe banned the use of growth-promoting antibiotics.
The Danish ban could provide valuable future data on whether there is a relationship between human antibiotics resistance and doses given to animals, said Ebner, the Purdue assistant professor.
But there isn’t a simple cause-and-effect relationship between livestock antibiotic use and drug-resistant illnesses, he said. The relationship appears to be more complex than that.
By JOE SIMON and BRENDA J. LINERT / Tribune Chronicle
POSTED: May 31, 2009
The scary thoughts racing through the mind of Youngstown State University wide receiver Ferlando Williams when he discovered he had a staph infection wouldn't have been nearly as frightening 15 or 20 years ago.
That's because the development or ''mutation,'' as Dr. Anthony Cutrona of Youngstown called it, of staphylococcus has been quite extraordinary.
The bacteria has been affecting people, especially athletes, since before antibiotics were around. Cutrona said staph has caused pimples and many other common skin infections for years, yet its consequences become fierce when an open wound forms because it then invades the blood stream.
The severity of such an infection has become much more destructive over the years. As doctors have developed antibiotics to combat the effects of staph, innovative strains of the bacteria have evolved and become resistant to the medicines.
''Initially, in the early '50s, staph was sensitive to penicillin,'' said Cutrona, the chief infectious disease doctor at St. Elizabeth Health Center, Youngstown. ''Then in the '60s it became resistant to penicillin and we derived a synthetic penicillin that it was sensitive to. Then in the '70s it became resistant to that, and we named that type of staph MRSA.''
This new, more complex type of staph known as MRSA (methicillin-resistant Staphylococcus aureus) was mainly found in hospitals, Cutrona said. MRSA has the same effects as a regular staph infection, but it is more difficult to kill because of its resistance to medicines.
Staph continued to fend off the different antibiotics and advanced into yet another form around 1992, called USA300.
''It was a little different than the (MRSA) we see in the hospitals,'' Cutrona said. ''It had this virulent (poisonous) potential. It could invade and destroy tissue. Initially it started out in pediatric cases. Kids that developed pneumonia with MRSA ... it killed them. Then we saw outbreaks in different places. We saw it in prisons, we saw it in daycare centers, schools, locker-room facilities. And usually, this particular USA300, that was MRSA but from the community (not hospitals), when it started out, people thought they had insect bites.''
Instead, though, these small, reddish bumps sprouting near cuts and scrapes were the early signs of a vicious bacteria. From 1990 through 2000, this USA300 strand was very rare, Cutrona said. Yet since the turn of the century, it has become much more prevalent. Cutrona said he saw it ''two or three times a month'' at one point. The dangerous part of this strain is what happens if not treated.
In November, YSU's Williams had noticed a pimple-like bump on his left elbow but mistakenly believed it was just an insect bite.
Looking back, Williams now realizes how close he came to losing a limb, or worse.
''That was one of toughest times of my life,'' he said. ''Another day or so and that would have been it for me.''
Threats as serious as Williams' are not all that uncommon among athletes. That wasn't the case years ago when staph was just as prevalent but not as lethal.
Dr. Blaise Congeni, director of Pediatric Infectious Diseases at Akron Children's Hospital, agrees that the increase in the number of cases has been significant.
''We see a lot of athletes. There undoubtedly is a substantial increase in athletes - and non-athletes,'' Congeni said recently.
''What I can tell you, which is probably substantially more important in my mind, is a substantial number of humans carry staph on their skin or nose. Over 50 percent of the strains are of the MRSA variety. So we know that is increasing. Prior to 2003, it was zero. The strain we are talking about may have arrived on the scene about 2000. Before that, nobody was carrying MRSA of the community acquired variety,'' Congeni said.
Cutrona echoed that.
''We've always had staph around, it's just that this particular strain, this USA300, is loaded with a packet of enzymes called PVL (Panton-Valentine leukocidin), and it destroys tissue, it destroys white blood cells,'' Cutrona said. ''The outbreaks in the area have been notably seen, for example, in high school sport activity areas.''
The reason cases have been seen at area schools is mainly due to poor hygiene and not washing clothes, Cutrona said. When athletes perform in the same jerseys and undershirts on a daily basis, the bacteria is more likely to be picked up because of the damp and unclean conditions areas where staph forms. If an athlete then suffers a cut or abrasion, doesn't shower after practice and ignores signs of an infection, the bacteria can enter the bloodstream.
''You even see it in professional sports teams the Cleveland Browns had an episode of it,'' Cutrona said. ''It has to do with personal hygiene and locker-room hygiene. You'll get outbreaks because, if you think about it, a lot of guys who are athletes or jocks, they don't always follow the most hygenic lifestyle.''
Congeni agreed that hygiene and good skin care are the keys to avoiding staph.
''No. 1, we recommend that you try to keep the skin as intact as possible,'' Congeni said. ''As smooth as silk.''