Antibiotic-resistant killer bugs spread to communities
Schools had been closed in the USA because of the problem of CA-MRSA (Community-acquired Methicillin-resistant Staphylococcus Aureus) and many people have died as a result of CA-MRSA.
In the USA, the National Centers for Disease Control in 2005 found that 94,000 Americans became seriously ill as a result of antibiotic-resistant MRSA infections; and 19,000 Americans were killed — more than the 17,000 Americans killed by AIDS.
With the spread of CA-MRSA to communities, more people will be affected. Find out what you can do to reduce your risks.
The common antibiotic-resistant bacteria, better known as MRSA (Methicillin-resistant Staphylococcus aureus), which used to strike only in hospitals, are now becoming widespread in public places. Today, new and more toxic forms of such bacteria are emerging that can kill people who have never even been in hospital!
The highly infectious new strains of the MRSA superbug that spread thorugh healthy communities may claim more lives than hospital-acquired infections.
Find out why, when, where and how they strike, and what you can do to protect yourself and your family.
Five continents — and spreading.
Hundreds of thousands, perhaps millions, of casualties — and counting. The world is now invaded by super-resistant superbugs that can attack healthy people, even the young, wherever they may be. Once encountered only in a hospital setting, now these killer microbes have struck in public places where there’s close contact among people. You can be infected even in the safety of your own home!
These much feared germs are airborne and spread easily. They can lead to life-threatening infections, and stronger and more potent antibiotics — yet to be invented — are required to fight them. They strike unawares, and are not easy to diagnose — leaving masked signs and symptoms that doctors easily miss.
Invasive, aggressive — and elusive: CA-MRSA — the stealthy 6-letter word life-stealer that has evaded doctors, alarmed scientists, has medical experts scrambling for cures that work, and that has put health authorities worldwide on heightened alert.
From UNTAMED …Superbugs in Hospitals
“Superbugs” or “smart” bacteria that have “learned” how to resist the arsenal of antibiotics, have been on the rise in recent decades. They can cause dangerous bacterial infections, which even the best antibiotics cannot cure.
In America today, according to the Centers for Disease Control, Superbug deaths may surpass AIDS toll. The Superbug threat is also prevalent in many other countries around the world, including Malaysia.
The reason: We have been overusing antibiotics (mainly due to overzealous antibiotic prescribing by doctors) and misusing the drugs (mainly through widespread use of antibiotics in livestock), and as a result, germs have figured out a way to become resistant to them.
The result: MRSA (Methicillin-resistant Staphylococcus aureus), a particular type or “strain” of Staphylococcus aureus bacteria that does not respond (is resistant) to many antibiotics. These antibiotics include methicillin, a type of penicillin.
MRSA, which is spread by casual contact, usually starts with minor abscesses and other skin infections. Confined to the surface of the skin, the bacteria do minimal damage. But in people with weak immune system (eg: children, the sick and the elderly), they can rapidly turn into serious health problems, including painful, disfiguring abscesses that eat away tissue.
… to UNWANTED …Proliferation of Hardier Strains
In some cases, the MRSA microbe gets into the lungs, causing unusually serious pneumonia, or spreads into bone, vital organs and the bloodstream, triggering life-threatening complications.
Such patients must be hospitalised and given intensive care, including intravenous antibiotics such as vancomycin. But even vancomycin, long the antibiotic of last resort reserved for hospitalised patients with MRSA infections, is becoming useless against bacteria — some hospitals in the world are already seeing outbreaks of vancomycin-resistant MRSA.
Death from MRSA and similarly resistant strains of bacteria are on the increase in many countries today. Hospital reports do not paint the full picture. Many hospitals overseas prefer to play down the MRSA factor and instead record the death as whatever the patient was suffering from, then add MRSA as a contributing factor, instead of the main cause. Some health authorities are only listing deaths from MRSA if the bacterium has entered the bloodstream and death has arisen from bacteraemia/septicaemia.
Many experts believe that estimates of deaths with MRSA as a contributing factor, are as high as 20,000 in the United Kingdom and a staggering 100,000 in the US, with some hospitals refusing to issue figures.
As more strains of MRSA develop, it is feared that MRSA may become the leading cause of death on the planet within a few years.
… and UNCONTROLLED…Newer, More Toxic Strains — in Communities!
MRSA used to be contracted only in hospitals or medical care settings. Not anymore. Today, antibiotic-resistant infections, which used to be acquired only in hospitals, are showing up in public places — in daycare centres, athletic fields, gyms and fitness clubs, prisons, correctional facilities, colleges, universities, even schools.
In other words, the deadly disease has become entrenched in wider communities. This means that anyone, and entire populations, not just hospital patients, can acquire the antibiotic-resistant infections!
Such infections, called community-acquired MRSA (CA-MRSA), have appeared with increasing frequency and are now epidemic within certain community populations in some countries.
In the US, for example, a little more than 10% of all MRSA infections are CA-MRSA (see also “World on Alert for Superbug”). Hospitalisation is required in about 1 out of 5 cases.
Identified as a lethal threat in 1999, this new strain is resistant to drugs and is highly toxic, responsible for 60% of all skin and soft-tissue infections treated in the country’s emergency rooms.
Two strains of Staphylococcus in the US (called USA300 and USA400) are associated with CA-MRSA. USA300 has emerged as the most prominent clone and is not found among hospital strains. It was not observed before the year 2000, when multiple other clones existed.
CA-MRSA: Old Foe, New Fangs
The difference between the hospital strain and the community strain is that hospital MRSA is almost always found in people with established risk factors associated with prior medical treatment. This is not so with CA-MRSA, which causes serious skin and soft tissue infections in otherwise healthy people who have not been recently hospitalised or undergone invasive medical procedures.
According to a study, drug-resistant Staph infections caught in the community may be more dangerous than those found in hospitals.
A major difference between the two types of MRSA is: The CA-MRSA bacterium secretes agents that attract and destroy immune cells that are supposed to protect against infection.
Unlike HA-MRSA, CA-MRSA has special genes that make it more likely to produce pus — it possesses a potent toxin called Panton-Valentine leukocidin (PVL), which attacks infection-fighting white blood cells called leukocytes. It has the ability to cause the body’s germ-fighting cells to explode, thus eliminating the body’s main defence against infections.
Dr John Conly, an infectious disease specialist and professor of medicine at the University of Calgary in Canada, calls it an “old foe with new fangs — a pathogen combining virulence, resistance and an ability to disseminate at large”.
CA-MRSA can be deadly.
An Aggressive “Superbug”
CA-MRSA is more vicious than the hospital-borne strain of MRSA (HA-MRSA), as it is able to evade the immune system. It can, among others, cause severe skin infections, including “flesh-eating” necrotising fasciitis (a severe, rapidly progressing and life-threatening skin infection), and potentially fatal blood poisoning.
Infections can recur and spread through families. The germ can penetrate bone and lungs, and the abscesses it causes often require surgery. In severe cases, up to a quarter patients die. In fact, people who contract MRSA can die in a matter of days (see “Silent Attack, Quick Death”).
“The new community associated MRSA strains appear to be more virulent and more easily spread between people,” says Dr Marina Morgan from the Royal Devon & Exeter Foundation NHS Trust in Britain.
“These community associated versions have been found in people with few, if any, reasons to have MRSA. Typically they haven’t recently been in hospital, or/and are not looking after or living with people with MRSA,” she told delegates at the recent Federation of Infection Societies Conference 2007 at the University of Cardiff, United Kingdom on 28 November 2007.
In recent years increasing numbers of cases of MRSA infection in the community have been seen in many countries around the world, particularly the US. Investigations of these cases have shown that in many instances, the strains of MRSA found in patients in the community are distinct from those strains seen in hospitals and it now appears that CA- MRSA have evolved independently of hospital MRSA.
Public health officials in some countries now consider CA-MRSA as a silent epidemic on the rise. In the US, for example, the country which is the hardest hit, more than 2 million people (almost 1% of the population) carry drug-resistant germs without symptoms, according to a January 2006 report (Journal of Infectious Diseases) by Matthew Kuehnert, amedical epidemiologist at the US Centers for Disease Control and Prevention.
Carriers can spread the disease and suddenly become ill themselves. What is alarming is that if CA-MRSA were to spread, victims’ lives would be at stake as the condition is not easily diagnosed and may not be treated in time, even in the most expert of hands.
Not Easy to Spot
The CA-MRSA strains are more virulent (ie extremely infectious, malignant or poisonous). In the medical context, it means they are capable of causing disease by breaking down protective mechanisms of the host. The majority of them produce the PVL toxin that kills white blood cells, the immune system’s first line of defence against pathogens like Staphylococcus aureus (bacteria commonly carried on the skin or in the nose of healthy people).
When this happens, the body responds by producing even more white blood cells to compenstate for those killed off by the first onslaught of PVL, and this produces the severe boils and abscesses
These infections are easy to miss, and can be dismissed as recurrent boils. It is not until the infection becomes serious that doctors then realise it could be something more serious. By then, it would have been too late to save the patient.
Infection by the PVL form of MRSA can, also, in some cases, lead to very severe infections like septicaemia and a deadly form of pneumonia called necrotising pneumonia, where the toxin eats away at lung tissue.
“With this type of necrotising PVL pneumonia, even with the strongest antibiotics, more than 60% of otherwise healthy young and fit people will die,” said Morgan.
Thus, with severe invasive infections like pneumonia, early diagnosis is vital to rule out CA-MRSA. In the case of children, Morgan said, treatment with the correct antibiotics and massive doses of immunoglobulin can save lives.
But the problem is, the condition is too easily missed, and to make things worse, highly spreadable — hence the widespread epidemic now.
How It Spreads
CA-MRSA is spread from human to human through close contact, so it spreads among family members at home, staff in the workplace and children in schools and nurseries, and also in athletic teams or any place where people congregate.
The infection can be spread by skin-to-skin contact as well as by sharing an item used by an infected person, particularly one with an open wound.
In hospitals, nursing homes and dialysis centres, they can hitch a ride inside the body on needles and other invasive devices, spreading through the bloodstream and causing severe illness.
They can also be spread by tattooing and drug use in prisons and by cuts and abrasions on the athletic field.
Who Is At Risk?
Children are especially at risk. Among children in the US, it has been found that the most frequent body parts affected are skin and soft tissues. Research also indicates that CA-MRSA may be becoming a more common cause of infection in other body sites, including the external and middle ear, in children.
CA-MRSA is currently spreading fast in the US and is a major cause of infection among American children.
Several reports have described this organism in individuals in prisons, military personnel, athletes (especially those involved in combat and ball sports, including wrestling and fencing), male homosexuals and ethnic populations (eg: native American Indians, Hawaiian islanders and Alaskan native people).
Risk factors for its acquisition include close physical contact, abrasion injuries and activities associated with poor communal hygiene (eg: sharing towels). This organism is now emerging in several European countries, as well as Asia.
Where the Vicious Bug Came From
Community epidemics of MRSA are indicated in some studies to originate from hospitals. In Scotland, a recent study at Aberdeen Royal Infirmary found that patients carrying MRSA are taking the superbug out of hospital and spreading it in the community.
Researchers now believe patients should be tested for MRSA when they leave hospital to halt infection levels. The research, published in the Journal of Hospital Infection, estimated that for every 10 cases of MRSA occurring in hospital, there would be 1 extra case in the community a month later.
It is estimated that 5-10% of patients discharged from hospital could be carrying the MRSA bug without showing any symptoms.
Scotland is set to start screening patients for MRSA when entering hospital. But the Aberdeen study has suggested that this be taken a step further — patients should be tested for MRSA when they leave hospital to stop it spreading in the community.
“The vast majority of MRSA in the UK is almost certainly acquired in hospital or nursing homes, but as nobody has ever published data from discharge screens we don’t know figures,” says lead researcher Dr Ian Gould.
Gould says that hospitals were probably reluctant to screen for MRSA on admission and discharge because it may provide “ammunition for litigation” among patients who are found negative on admission but positive when leaving hospital.
However, some experts believe that CA-MRSA strains are only distantly related to HA-MRSA strains, with the community-based strain rising on its own.
According to Dr Robert S. Daum, Professor of Pediatric Infectious Diseases at the University of Chicago in the US, “Molecular typing … revealed that the community-associated strains of MRSA affecting healthy people in the community were not the hospital strains simply migrating into the community (although that has also occurred to some extent), but rather the development of novel strains that have arisen de novo (i.e. anew or afresh).
“This is a crucial point that many people trying to understand the CA-MRSA epidemic have not yet grasped.”
The following informative articles are available from Utusan Konsumer January-February 2008:
- Silent Attack, Quick Death
- Infected people may be wrongly treated
- World on Alert for Superbug
- MRSA: Are you at risk?
- How the infection starts
- Bacterial resistance: how bad is the situation?
- MRSA in Malaysia
- What you can do