Worrisome Infection Eludes a Leading Children’s Vaccine

By LAURA BEIL

A highly drug-resistant germ has become a common cause of meningitis, pneumonia and other life-threatening conditions in young children. The culprit — a strain of strep bacteria — can conquer almost all antibiotics in pediatrics, and has dodged a vaccine otherwise credited with causing the number of serious infections in children to plummet.

Since 2000, American toddlers have been immunized against Streptococcus pneumoniae, or pneumococcus, an organism that preys largely on children younger than 5 and the elderly. Pneumococcal meningitis can be fatal, and survivors are often left with deafness and other lifelong neurological problems.

And by most measures, the vaccine has worked: by 2002, rates of infection from these bacteria had dropped as much as 80 percent in some places. But progress has now stalled, and infection with a particular type of pneumococcus, Serotype 19A, is steadily rising.

“It’s very much a concern,” said Bernard Beall, a pneumococcal expert at the federal Centers for Disease Control and Prevention. Last year, in The Journal of the American Medical Association, pediatricians described an outbreak of Serotype 19A ear infections in Rochester that could be cured only by surgically implanting tubes, or by turning to adult medicines not yet tested for safety in children.

A greater worry, however, is the frequency of meningitis, pneumonia and bloodstream infections from Serotype 19A. Since 2001, rates of these and other invasive pneumococcal diseases have crept upward, to more than 10 per 100,000 children from about 2 per 100,000. A fourfold increase in life-threatening infections has also occurred among the elderly.

The vaccine, Prevnar, is aimed at seven types of bacteria that were responsible for 70 to 80 percent of pneumococcal illness during the 1990s. Because pneumococci come in 91 forms, experts have worried from the start whether bacteria that were just as deadly, but not wiped out by the vaccine, might move in as opportunists when the competition suddenly vanished.

“Nature abhors a vacuum,” said Dr. Steven Black of Cincinnati Children’s Hospital. Indeed, almost all pneumococcal infections among American children today are caused by versions not covered by the vaccine, and 19A is leading the way. “People hoped against hope it wouldn’t happen,” he said.

The vaccine’s manufacturer, Wyeth, says it has been working quickly to develop a new product to counter 19A and five other pneumococcal variations, along with the original seven. The company will release results of the first large studies of the newer version this month at an infectious disease meeting in Washington.

“There was no point where we said to ourselves, ‘We missed it, we need to put in 19A,’ ” said Emilio A. Emini, head of vaccine research and development for Wyeth. The company was always prepared to remake the product, he said.

Once a new vaccine demonstrates that it can protect against pneumococcus, it must work its way through the approval process — passing tests of effectiveness and safety — before it can be licensed. Researchers will also try to determine whether young children who have been immunized with the old Prevnar should be revaccinated to protect themselves from 19A.

The remodeling of a vaccine so soon after its approval is highly unusual, but so was the effort to tackle pneumococcus.

The bacteria live in the nose and throat, usually as microbial freeloaders of no consequence. Occasionally — often after a simple viral infection — pneumococci slip into inner areas of the body and cause disease. Weaker immune systems in the very young and the very old leave them most vulnerable. (The pneumonia shot in older people includes 19A, but many elderly people have not received the immunization.)

Not all of the 91 incarnations of pneumococcal bacteria are dangerous. They developed so much variety by mingling in the back of the throat, exchanging genetic material as eagerly as children trading Halloween candy. The variation in genes slightly alters how the bacteria function and how they are received by the immune system.

For vaccine manufacturers, pneumococci’s diversity presented a challenge: how to teach the immune system to recognize a target that may look a little different from child to child. “This is the most complex biological product ever made,” Dr. Emini said.

Serotype 19A was around in the 1990s, though uncommon, and the vaccine includes a similar version called 19F. The hope in 2000 was that 19F looked enough like 19A to set off an immune reaction. It did not.

Experts say it is hard to know what role the introduction of Prevnar may have played in the rise of the bacteria, which was gaining momentum in some countries before the vaccine’s adoption. For example, researchers from GlaxoSmithKline, which is introducing its own pneumococcal vaccine, reported last month that Serotype 19A became more common in Belgium from 2001 to 2004 — years when pneumococcal vaccination was rare in that country. Similar reports have emerged from China, South Korea and Israel.

Pneumococci ebb and flow in natural cycles, and some types have gained a survival advantage by growing resistant to a host of drugs. The vaccine may have simply amplified natural trends..

“I don’t think anyone can tell you the relative contributions of these factors,” said Dr. Sheldon L. Kaplan of Texas Children’s Hospital in Houston. This summer, he and his colleagues described a growing number of cases of drug-resistant mastoiditis, an infection of an inner-ear bone, from 19A.

Experts are now watching to see how forcefully the organism will spread before the new immunization arrives. Wyeth says it hopes to file an application with the Food and Drug Administration in 2009.

Disease experts also wonder what organisms like 19A mean for the future of pneumococcal infections. Public health experts once hoped the infection could be defeated, but it now appears that pneumococci may be playing a game of cat and mouse.

“The pneumococcus has shown an extraordinary ability to evolve to our strategies,” said Dr. Beall of the C.D.C.

Yet he and others are quick to say that immunization remains highly effective, even if it leaves some children behind. “This is not a failure of the vaccine,” said Dr. George H. McCracken Jr. of the University of Texas Southwestern Medical Center at Dallas. Even with the rise of 19A, children are much less likely to become ill from pneumococcal infections.

Dr. McCracken hopes that researchers will one day avoid threats like 19A entirely by developing a vaccine that primes the immune system to recognize some element common to all 91 types of pneumococci — in the way a quiche, an omelet and a custard pie are all versions of eggs. But until such an immunization comes along, he said, pediatricians will be forced to battle the pneumococcus as they always have, by trying to stay one strain ahead of its game.

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The Evolution of Trojan Man

By Kate Rope

When I was in middle school, I remember giggling at a condom ad that ran on late-night radio. A couple would be about to, you know, do it! when Trojan Man would ride up on his horse and give the amorous pair a simple weapon in the war against sexually transmitted diseases and unwanted pregnancy: a small piece of latex. I can still remember the baritone voice-over announcing his arrival: “TROJAN MAN!” It seemed so mysterious and exciting! (Of course, I would later learn that the word exciting is not really the most apt one to use when describing a condom.)

My, how times have changed. Recently, MTV and Trojan launched a campaign, Evolve One, Evolve All, asking real people to upload their own videos about whether they use condoms and why (a grassroots ad campaign, if you will). If you post a video or comment on the site, up to five condoms are donated to Americans at risk. The plan is to donate one million condoms across the United States, but the larger plan is obviously to make talking about and using condoms a natural and normal part of sex in America.

Yes, it’s a lot less mysterious than Trojan Man, but that’s the point.

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How much sleep do you really need? Probably a lot less than you think, says an expert

By Professor Jim Horne

Ask people whether they would like more sleep and the majority will say yes.

But does this mean they are not getting enough? I don't believe so.

Thanks to oft-repeated assertions that our ancestors slept longer than we did, not to mention claims that a lack of shut-eye can cause high blood pressure, diabetes and obesity, and it's easy to see why we think we are chronically deprived of sleep.

Wake up you sleepy head: Most people need less than 8 hours of sleep each night

The fact is, most of us are probably getting more sleep than we strictly need - we've just convinced ourselves we're sleep deprived.

It's nothing new. In 1894, the British Medical Journal ran an editorial warning that the 'hurry and excitement' of modern life was leading to an epidemic of insomnia.

But far from being chronically sleep-deprived, I believe things have never been better.

Unlike the typical worker from 150 years ago, who toiled for 14 hours a day, six days a week and went home to a crowded, flea-infested bed, most of us sleep perfectly adequately.

There have been several large studies over the past 40 years into how much sleep people actually get. The findings show that the average healthy adult sleeps for seven to seven-and-a-half hours a night.

The much-repeated 'fact' that our ancestors used to sleep around nine hours is a myth and originates from a study in 1913 by researchers in California, which found that children aged eight to 17 slept for this amount of time.

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Even today, this figure holds true for that age group - as the parents of any teenager will attest!

But adults do not need so much sleep. Some thrive on five hours a night, while others need seven.

The only part of your body that would be affected by a true lack of sleep - and that means several days without any sleep - is your brain.

Tests prove that there's no physiological difference in the muscles or organs of the body when you're asleep as opposed to when you're simply lying still and fully awake.

The brain however, is another matter. It needs sleep. Although it comprises only 2 per cent of your total body weight, it uses 20 per cent of the energy you consume in your body.

There are three main parts to the brain - the cortex, the mid-brain and the hind brain.

The mid and hind brain work flat out to control your motor functions, such as breathing, blood pressure, heart rate and liver function. They carry on working even when you're in deep sleep.

But the cortex, which controls thinking, speech, memory and perception needs time off - and that occurs when you go to sleep.

Without it, these functions deteriorate rapidly. After only one night without sleep, we are unable to deal with as much pressure, we get more irritable and we can't cope with disruption to our routine.

We forget things, we become like robots, unable to have conversations with people, unable to work out simple lists or sums.

Yet there are some parts of the cortex which are remarkably resilient.

In 1966, a 17-year-old high school student called Randy Gardner raised money for charity by staying awake for 11 days. It remains a record.

Four days into the experiment, he began to hallucinate. Towards the end he could barely converse with people or perceive what was going on around him.

But he could play pinball with remarkable ease. The part of the cortex which controls hand/eye coordination appears to be unaffected by lack of sleep.

There is a lot of fear-mongering about the so-called dangers of lack of sleep - but, in fact, the biggest danger of not having adequate sleep is having an accident, such as falling asleep at the wheel of a car.

Of course, I would never dismiss the distress that insomnia causes. But people who suffer from it tend to be very stressed - whether through work or a bereavement - and it's the stress that wears down their immune system and makes them more susceptible to infection.

Yet despite the fact most of us do get enough sleep, a whole industry has emerged to help us with our 'sleep problem' and I warn: 'caveat emptor' - let the buyer beware.

Herbal preparations or drinks are a useful short-term crutch for those suffering from sleepless nights, in the sense that people feel reassured that by taking them they will have a good night's sleep.

Drugs are inadequate in the long term because insomnia is not a physiological problem - it's a psychological one, usually caused by stress.

The only way to treat a true insomniac is by tackling their problems while they're awake.

Once the waking problem is sorted, they will find it much easier to drift off - and get the hours of sleep they need, not some arbitrary 'ideal' based on misinterpretations of history.

• Sleepfaring - A Journey Through The Science Of Sleep by Professor Jim Horne (Oxford University Press, £6.99).

Lavender, silk... and turn off the TV

Room temperature: The ideal temperature is 18c, according to Chris Idzikowski from the Edinburgh Sleep Clinic. This will ensure your body's core temperature drops enough to encourage sleep. If the room is too warm (above 24c) your brain won't send the correct triggers for sleep. If the room is too cold (below 12c), the body will struggle to maintain temperature and disturb sleep.

Duvet: Have both a summer and a winter duvet. A 10-13.5 tog winter duvet will be far too warm for the summer months, when a 4.5 tog is ideal.

Ventilation: Always have an open window, even in winter. Fresh air encourages sleep.

Your bed: Don't scrimp - this is where you will spend 25 years of your life. The typical person sweats half a pint of liquid during the night and changes position 40-60 times. Dr Neil Stanley, from the British Sleep Society, recommends choosing a good, supportive bed base with a firm, thick mattress. Your mattress should be changed every 12 years and a futon should be kept for a maximum of three years.

Bed linen: Cotton and linen are best as they absorb more moisture.

Lavender: You could sprinkle a tiny amount of lavender oil on your pillow or spray some in the air. Extensive research shows it can improve the quality of sleep by 20 per cent.

Nightwear: Loose and made of natural fibres. Bed socks are a good idea as warm feet signal healthy blood flow to the brain, inducing restful sleep.

Alarm clock: Turn it down or preferably off. Dr Neil Stanley says: 'Anticipating a shrill alarm clock is stressful and will make insomnia worse.'

Curtains/blinds: As thick and heavy as possible. Ideally, a bedroom should be totally dark until 4am for optimum sleep. Darkness stimulates the pineal gland to produce the hormone melatonin, which induces sleep. Switch off your landing light, too - even low levels of light under a door can keep you awake.

Television: Don't have one in the bedroom. 'It should be a haven of tranquillity,' says Dr Stanley. 'When you walk in, your mind must get the message that this is the place for sleep.'

Partner: If your other half is a fidget or a snorer, consider separate beds. Dr Stanley says: 'People who have poor sleep have higher rates of divorce and separate beds can improve, not ruin a sex life.'

Warm bath: This will soothe you and relax your muscles, but avoid showering as this will wake you up.

Avoid alcohol: Alcohol encourages the production of nore-epinephrine, a hormonelike neurotransmitter secreted in response to excitement and stress. Hours after drinking, a burst of noreepinephrine can disrupt your sleep and is likely to wake you earlier than usual.

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