The Associated Press
AP

Drugmaker Merck & Co. says the Food and Drug Administration is reviewing its second application to sell a new type of allergy treatment meant to gradually reduce allergic reactions over time, rather than just relieving sneezing, itching and other symptoms temporarily. 

Merck's latest application is for an allergy immunotherapy tablet for ragweed allergies that dissolves under the tongue. Patients in studies of the tablet took it daily for a year.

It could become an alternative to months of uncomfortable allergy shots. Both methods gradually desensitize the immune system to the substance triggering the allergic reaction.

In March, the Whitehouse Station, N.J., company said the FDA was reviewing its application for an immunotherapy tablet for grass pollen allergies.

Merck expects FDA rulings on both still-unnamed treatments in 2014's first half. 

By Steve James, NBC News contributor 

Allergies triggered by food or the environment have risen sharply in U.S. children in recent years, especially among more affluent families, according to a large government study. The "epidemic" rise in allergies, as one expert describes it, is of concern because it increases the risk of potentially fatal respiratory diseases or disfiguring skin conditions that could require long-term care.

The latest data, released on Thursday by the Centers for Disease Control, showed the prevalence of food allergies increased in children under age 18 from 3.4 percent in 1997 to 5.1 percent in 2011. Skin allergies rose from 7.4 percent to 12.5 percent in the same time period.

 “Allergic disease is an epidemic and it may not have plateaued yet," said Dr. Sakina Bajowala, an allergist in suburban Chicago, who was not associated with the CDC study. “Every day we get new calls from patients. We see a lot more kids, not with just one allergy, but several."

The CDC numbers show that black children are more likely to suffer skin allergies, while whites are at greater risk of respiratory problems. But the data also reveals that that the prevalence of allergies increases with income level and children whose family income is 200 percent of the poverty level had the highest prevalence rates.

According to the CDC’s National Center of Health Statistics, younger children were more likely to have skin allergies, while older children were more likely to have respiratory allergies. Hispanic children had a lower prevalence of food, skin and respiratory allergy than children of other races.

CDC statistician Lajeana Howie, who helped conduct the study, said researchers looked at data from 9,000 to 12,000 people representing a cross section of the U.S. population. But, she said, the study only looked at the prevalence of allergies, it did not determine the causes.

Howie said she could not speculate why children from more affluent families had higher incidences of allergies, because of the confidential nature of the CDC study.

Dr. Bajowala, whose practice is in the relatively affluent suburb of Aurora, Illinois, said: ”There is no hard data to explain why affluence is related to allergies.” In an interview with NBCNews.com, she suggested various reasons, ranging from more frequent doctor visits by affluent parents with health insurance, basic differences in diet between poorer and better-off kids, or a higher frequency of antibiotics in some children.

Foods are the most common cause of anaphylaxis—a potentially fatal severe allergic reaction-- among children and adolescents, the CDC said.

Just this week, Bajowala said she treated a 6-year-old boy with life-threatening allergies to more than five different foods, a 4-year-old girl with severe eczema over 20 percent of her body and a wheezing 3-year-old child whose parents worry might develop asthma.

 That case load is not unusual for Bajowala, who says she is seeing more and more children with skin and respiratory allergies triggered by food, such as eggs, or nuts or shellfish, or by pollution, diesel fumes, dust or even mice and cockroaches.

Bajowala, who is a fellow of the American Academy of Allergy, Asthma and Immunology, said that allergies are caused by a combination of genetics and the environment.  “You don’t become allergic to something you have not been exposed to,” she said. “Some, you inherit from your parents, but the environment has an effect, too.

“You could have identical twins, with the same genes and raise them in different environments, and one may manifest an allergic disease and the other may not.”

 The key to treating allergies, she said, is determining the allergen that is causing the reaction in a particular patient and then using specific immunology to counter it.

“Immunotherapy has a more than 80 percent success rate,” Bajowala said. “I like to explain to my patients that their immune system is overreacting (to an allergen) and we are retraining it to tolerate something it did not tolerate before.”

Such treatment is essential to stop the Atopic March -- the typical progression of allergic diseases that often begin early in life. These include atopic dermatitis (eczema), food allergy, allergic rhinitis (hay fever) and asthma.

“I may see a baby with a skin rash and later they get hay fever and that leads to asthma,” said Bajowala, who said 60 percent of her patients are children.

“Allergies are not a joke, it is very frightening for families impacted by it – they do not want it to control their lives, but it does.”

Dr. Jonathan Silverberg, an allergist in the dermatology department at St. Luke’s – Roosevelt Hospital in New York, said he was not surprised by the CDC figures. “We know it is on the rise, it just keeps going.”

Silverberg just published a study that showed that children born outside the United States had significantly lower odds of developing allergies than American-born children. “However, foreign-born Americans develop increased risk of allergic disease with prolonged residence in the United States,” he said.

He attributed the difference partly to the fact that children overseas are more likely to be exposed to diseases that build up protection against allergies. Also, the Western diet is associated with more allergic disease.

Silverberg said his patients from overseas question him daily. ”They say: ‘I came here from the Caribbean or Mexico and I never had problems like this. My skin flares up here but if I go back home, the problem is solved.’

 “Clearly there is something in the short- or longer-term exposure here,” Silverberg said.

He said his study was based on responses from 91,642 children to a National Survey of Children’s Health in 2007-08.

If you’ve been feeling guilty because you can’t keep your house spotless, stop.

As it turns out, allowing the odd germ to flourish here or there just might be saving your kid from a lifetime of allergies, Dr. Nancy Snyderman explained on "NBC Nightly News with Brian Williams" Monday.

It seems counterintuitive, but that’s exactly what the so-called "hygiene hypothesis" suggests. You can actually be too clean for your own good.

Scientists came up with the hypothesis as a way to explain the explosion of allergies and asthma in America’s youth. And what they discovered was intriguing, if a little disconcerting: kids who grow up in less tidy environments end up with a lower risk of developing sensitivities to benign substances, like pollen and dog dander.

A study released in June added to the growing mound of evidence that the too-clean-for-health hypothesis might be on track. That study, published in the Journal of Allergy and Clinical Immunology, found that Amish children who were raised on farms were less likely to develop allergies and asthma than their peers.

Why would exposure to dirt and microbes make a kid less sensitive to pollen and the like?

For one thing, it’s exposure to pathogens that allows the immune system to become fine-tuned as it learns to differentiate between harmful and harmless irritants.

Beyond this, exposure to certain bacteria gives the immune system's dedicated "fighters" something to do.

“I believe that the immune system is like an army,” explains Dr. Samuel Friedlander, an allergist at University Hospitals Case Medical Center in Cleveland. “So, if the army doesn’t have something to fight like microbes, it’s going to fight things like allergens in many cases. People [who] live on farms are exposed to more microbes and as a result the immune system tries to fight those bugs and then, in turn, the body doesn’t have to fight allergens.”

Dr. Richard Gallo puts it a little differently. If you keep your environment too clean – by using too many bacterial soaps and hand sanitizers, for example – then your immune system becomes more sensitized to any irritant that comes its way.

“It’s a change in your allergic set point,” says Gallo, a professor and chief of dermatology at the University of California, San Diego. “So being too clean can lead you to have a high allergic set point that will overreact to the environment.”

Does that mean we can all throw out our mop buckets and soap? No, experts say. We still need to keep things clean, just not Bubble Boy antiseptic.

And there's an interesting side note: Some really intriguing animal studies have shown that you might be able to reset your immune system even after you’ve grown up by exposing yourself to certain types of bacteria.

“Some very recent studies that have been published in very excellent scientific journals have shown that with the introduction of specific bacteria in laboratory animals, you can completely reset their immune status and their capacity for certain allergic responses,” Gallo says.

And keep in mind, experts say, that some bacteria are fairly benign.

“So my advice is that some hygiene is good, too much is bad,” Gallo says. “In many cases you have to use common sense. You’re in a situation where you’re likely to be exposed to pathogens – germs that could cause disease – it’s a better idea to use sanitizers to remove them.

"But indiscriminate use - overusing hand sanitizers, anti-microbial soaps and so forth - is also going to be doing harm. So you have to balance the two.”

It’s Healthy Week! Learn the small steps you can take in your life to go healthy and "like" us on Facebook! And then follow up on Twitter at twitter.com/healthyatnbcu 

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By Trevor Stokes, LiveScience contributor

People allergic to whey may be able to drink newly engineered milk without the unpleasant digestive consequences, according to research released Monday.

A team of New Zealand researchers genetically engineered a cow named Daisy to produce milk free of β-lactoglobulin protein that can cause allergic skin, digestive and respiratory reactions predominantly in infants.

"Since the protein is not produced in human milk, it's not surprising that this protein may be recognized as a foreign protein in infants and cause allergies," study author and scientist at AgResearch in New Zealand Stefan Wagner told LiveScience.

Studies show that about 1 in 12 infants develops an allergic response to whey, but most infants are able to outgrow their allergy.

For decades, food manufacturers have broken up whey protein, a mix of about 10 proteins including β-lactoglobulin, in milk products through a process called hydrolysis in an effort to decrease its allergenicity. [9 Weirdest Allergies]

"Infant formula uses hydrolyzed milk, which is supposed to be much less allergenic, but there is still residual risk to exposure of allergies," Wagner said.

Some outside researchers expressed concern because while the milk produced by Daisy does show much less β-lactoglobulin, it held more of a non-whey protein called casein, which is also responsible for allergies. "We wouldn't think that this has any relevance to milk allergy; whey protein is one of many, many proteins that people can be allergic to," said Robert Wood, allergy and immunology chief at The Johns Hopkins Hospital, who was not involved in the new research. 

Making Daisy
So instead of relying on manufacturing methods, the researchers focused on getting the source material free of whey.

To decrease whey in milk directly, the New Zealand group created a cow free of β-lactoglobulin. To do so, they combined two tools: Nuclear transfer, a technique established during the days of cloning the famous Dolly sheep; and RNA interference, a technique relatively new for livestock used to shut down genes.

The researchers inserted a DNA fragment into cow somatic cell lines, or those not inherited, for cow-lactating tissues; this DNA element shuts down production of β-lactoglobulin in lactating tissues. Researchers then transferred the transgenic nuclei into unfertilized egg cells that, when stimulated, became embryos that were implanted into cows — a total of 57 cloned cow embryos. [Genetics by the Numbers: 10 Tantalizing Tales]

The process resulted in five pregnancies — one of which was terminated to collect cells. Of the four remaining pregnancies, one resulted in offspring.

The whey-reduced milk is years away from market, if it ever makes it to grocery shelves.

"We are nowhere near any clinical tests — what we are currently doing is to show that milk from our transgenic cow is indeed less allergenic," Wagner said.

A ways to go

But why go to all the bother of producing a transgenic cow when manufacturers can reduce whey in postproduction?

"When we process milk with heat or enzymes, we lose some of the nutrients that are essential to our body," Anower Jabed, who completed his doctoral work on the transgenic cow and is currently at the University of Aukland, told LiveScience. "It is a way to solve the problem where we don't have to process every time."

Daisy was born unable to produce the major allergen in whey, but also born four weeks prematurely, and, to the surprise of researchers, without a tail.

"We do have evidence that suggests that the lacking tail is due to an epigenetic defect (that affects gene expression rather than the genes themselves), and we believe it is not related to the genetic modification of the calf, but this must be backed up by more results," Wagner said.

The whey-reduced milk still contained other allergenic proteins and even increased casein, the main protein that coagulates to form cheese.

However, getting cows to produce hypoallergenic milk may be far-fetched, according to some researchers.

"While it's an interesting idea, that's not going to eliminate the allergies," said Hugh Sampson, an immunologist at Mount Sinai School of Medicine, who was not involved in the current study.

Because federal law says transgenic milk can't be consumed, the researchers aren't sure what it tastes like yet.

Jabed hopes that isn't the case in the future.

"When I started this project in 2007, it was my dream to see a hypoallergenic cow, I wish in the future we can produce (hypoallergenic) milk and market it and see it in store shelves," he said.

The journal the Proceedings of the National Academy of Science published the research today.

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Giving children with egg allergies small, and then increasingly higher, doses of the very food they are allergic to may eliminate, or at least reduce, reactions, a new study shows.

In a multi-center trial, 28 percent of kids experienced long-term elimination of egg allergies, while another 47 percent were able to tolerate some egg in their diets so long as they were on regular therapy, according to the study published in the New England Journal of Medicine.

Called oral immunotherapy, the treatment is similar to the allergy shots people receive to reduce sensitivity to allergens such as dust, cat dander and ragweed, explains study co-author Dr. Robert Wood, director of allergy and immunology at the Johns Hopkins Children’s Center.

“Not having to worry about little exposures, and to be able to eat your birthday cake, is huge for these children,” Wood says.

Stephanie Kuroda agreed. Kuroda, the mom of Tad Berkery, now 10, one kid in the study who didn’t completely overcome his egg allergy, says she’s happy that her son is now able to eat foods that contain eggs so long as he gets a regular dose of egg protein in his diet.

Before the trial, “just 1/1,000 of an egg could cause breathing problems,” she explains. “It affected his life tremendously. We had to make his all his food and take it everywhere he went. He had to sit at a table separate from everyone else.”

And it wasn’t just Tad’s safety that Kuroda worried about. It was also how the allergy was affecting his social development.

“You end up with a child who is a little more separate from everyone,” she says. “As a parent you wonder how will this affect him. He goes to birthday parties and everyone else has cake and you have to bring his own dessert for him.

“It all contributes to making a child more hesitant to try new things – and not just food. From a safety standpoint that’s good, but from the standpoint of a childhood that should involve seeing the world and learning about new things, it’s not.”

About 8 percent of U.S. children have some sort of food allergy. More than 600,000 Americans, or 0.2 percent of the population, have an egg allergy. The numbers are highest among children, many of whom eventually outgrow their symptoms.

For the new study, 40 children between the ages of 5 and 11, were given small doses of egg white that increased with time. Another 15 children were given a cornstarch placebo powder.

Thirty-five of the 40 stuck with the study, and at the end of 22 months, they were tested with a larger dose of egg white powder -- the equivalent of half an egg. Of those, 30, or 75 percent of the original 40, had no reaction.

For the next four to six weeks, the children were then taken off their daily egg dose. When they were retested with the larger dose of egg white powder, just 11 children, or 28 percent of the original 40, had no reaction. A year later those children were eating eggs regularly, the researchers reported.

Wood believes this method will work on other food allergies, too, including peanuts. 

For those like Tad who didn’t pass the second test, it may be enough to know that regular doses of egg whites could keep an egg allergy at bay. 

“It’s life changing and liberating,” Kuroda says. “And it’s certainly made the world a lot safer for him. I think he’s more confident now and not so tentative as a result of the immunotherapy study.”

Related: 

• For healthier kids, get a cat or dog
• Food allergies more common in city kids

By Susan E. Matthews
MyHealthNewsDaily

Kids who grow up with cats or dogs tend to get fewer respiratory infections during their first year of life, according to a new study from Finland.

Researchers followed 397 children from pregnancy through their first year of life, and found that those living with dogs developed 31 percent fewer respiratory tract symptoms or infections, 44 percent fewer ear infections and received 29 percent fewer antibiotic prescriptions.

Contact with cats was also linked with fewer infections, but the effect was not as drastic as contact with dogs — for example, infants living with cats were 2 percent less likely to need antibiotics.

"We speculated that maybe the dogs somehow can bring dirt or soil inside the house, and then the immune system is strengthened, or maybe it’s something about the animals themselves," said study researcher Dr. Eija Bergroth, a pediatrician at the Kuopio University Hospital in Finland.

The link between pets and fewer infections held even when researchers took into account factors known to affect infants' infection rates, such as breast-feeding  and number of siblings. Still, the researchers acknowledged that couldn't account for all such factors, and noted that they found a correlation, not a cause-and-effect relationship.

Of the children in the study, 35 percent lived in homes with dogs, and 24 percent lived in homes with cats, though the researchers also accounted for pet contact  outside the home.

"According to our results, there’s no reason to be afraid of animal contact, or to avoid them," Bergroth said. While many people preparing to have a child attempt to create an extremely hygienic environment, Bergroth said, the results show this may not be the best choice, because the immune system is not challenged. 

The new findings are "incredibly novel," said Dr. Roya Samuels, a pediatrician at Cohen Children's Medical Center in New Hyde Park, N.Y., who was not involved with the study.

The research builds on the "hygiene hypothesis," a widely accepted theory that posits that children exposed to too-clean environments are more likely to develop allergies and asthma. The findings imply that the benefits of living in an environment that is more challenging to the immune system extend to lower rates of infectious diseases as well, Samuels said, which had not been previously shown.

"We associate exposure to dog and cat dander with lower allergy and asthma rates. But this paper is saying that, for reasons unknown, there is a protective mechanism at work lowering rates of infectious diseases," Samuels said.

However, exactly how this protection might work isn't clear, she said. While the researchers speculated that dirt in the home was behind the link, Samuels said there may be more to the story. Future studies to confirm the findings should further investigate the mechanisms at work, she said.

Bergroth said she hopes the research will stop people from thinking that if "they’re having children, they should get rid of animals."

Bergroth emphasized that the children studied lived in rural or suburban areas, so the study results may not translate to urban children. But she also said that urban pets may not track in the same dirt.

Karen Rowan contributed reporting to this story.

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Dr. Tyeese Gaines, an emergency medicine physician and health editor for theGrio.com, answers your questions about everything from shingles to concussions. Got a question you'd like her to answer in an upcoming column? Send it to askdoctorty@gmail.com.

Q: Is it normal for a child to develop a food allergy all of a sudden (in this case, shellfish)?
- Elizabeth C.
A: Yes. Allergies can develop at any time. They’re more likely to start in childhood, but anyone -- even adults -- can become allergic to foods that that person has eaten his or her entire life.

Q: I’m pregnant with our second child and due in August. Both my obstetrician and my son’s pediatrician recommend that my husband and I get a pertussis booster shot (for whooping cough).  My husband was in the ER and given a tetanus shot. Do all tetanus shots come with pertussis in them?
- Sarah D. J.
A: No. There are vaccines with tetanus alone, and others with both tetanus and pertussis. We get excited about pertussis vaccination because pertussis -- the bacteria that causes whooping cough -- is highly contagious and dangerous to infants. The current recommendation is to give pertussis when adults get tetanus vaccines because it decreases the chances of adults passing pertussis onto the children.

Q: Why is it that when I go to the emergency room for a mega migraine everyone assumes I am a pill popper or drug addict? If I wasn’t in such unbearable pain and vomiting, I wouldn’t go.
- Aron B.
A: Unfortunately, there are people looking for prescription pain medication for the wrong reasons -- not because they have pain, but because they either want to get a euphoric high or sell the pills illegally. The problem is, it can be difficult to tell the difference. If you have two patients writhing in pain, but one is being deceptive, how do you know? And, in your case, patients who come in frequently do tend to raise flags. The best thing to do is get a good primary physician who knows you well. Either he or she can prescribe you pain medication and help you avoid the emergency room altogether or that physician can call the ER and “vouch” for you and the fact that you’re not drug-seeking. 

Q: Black spots keep coming up on my face, and my neck is darker than the rest of my body, what can I do to clear it up?
- Nic-nak J.
A: The neck can be darker than the rest of the body, especially in the folds, in a condition called acanthosis nigricans. Sometimes, it is benign, other times it means there is an underlying health problem. Acanthosis nigricans affects people of African descent more often, and tends to run in families. Obesity and other hormonal problems can lead to this discoloration. And, it is often seen in obesity-related diabetes -- sometimes as a warning sign long before the patient develops diabetes.  The darker discoloration can spread to the armpits, groin and finger joints. It fades once the underlying cause is treated.

The spots that appear on the skin with age are usually signs of long-term sun damage. It also appears to be related to genetics. Visit your physician or a dermatologist to figure out whether those are aging spots or discoloration to be concerned about.

Q: I am not a drinker. I may have a drink once or twice a month. Sometimes, when I drink, I get the “blood pressure headache.” Is it safe to pop another pill prior to having a drink in order to control my blood pressure?
- Lynn E. P.
A: This concept of people developing a headache when their blood pressure is high is often debated. The problem is, pain can increase a person’s blood pressure, so simply having a headache can make one’s blood pressure go up. If the blood pressure is taken at that point, who knows which caused which?

With respect to your headache, some people do develop headaches when drinking alcohol. Some are very sensitive to the dehydration that comes with even a small amount of alcohol intake. Others are affected by the chemicals in certain types of alcohol, such as red wine -- a well-known trigger in migraine sufferers.

Talk to your doctor and don’t assume that taking an extra blood pressure pill will prevent the headache. It may not be caused by your blood pressure at all.

Q: If it’s late at night, or on a weekend, can you help parents decide if they should take their child to the ER as opposed to calling their on-call pediatrician or waiting until office hours?
- Michelle V. S.
A: If the child is having difficulty breathing, or some other life-threatening condition, call 911 immediately. Otherwise, call the pediatrician. There is always someone on call for their patients. The truth is, many pediatric ER visits can wait until the morning when the pediatrician’s office is open. Allow the doctor to help with that decision. He or she may even call in the prescriptions you need to the pharmacy without you having to come in.

Dr. Tyeese Gaines is a physician-journalist with over 10 years of print and broadcast experience, now serving as health editor for theGrio.com. Dr. Ty is also a practicing emergency medicine physician in New Jersey. Follow her on twitter at @doctorty.

Note: The information included in this post is for educational purposes only. It is not intended nor implied to be a substitute for professional medical advice. The reader should always consult his or her healthcare provider with questions. Reading the information on this website does not create a physician-patient relationship.

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By Joan Raymond

It's not just here in the US, Britain started off with a milder than average winter, when cherry blossoms were blooming at Christmas.

Spring is still around the corner, but the problem for many of the 40 million Americans who suffer seasonal allergies is that Mother Nature, which bestowed an unusually mild winter on most of the U.S., is giving them a big punch in their already drippy little noses. Allergy season seems to be starting earlier this year -- and it’s going to be lasting longer.
 
“What we’re hearing, at least anecdotally, is patients saying their allergies are more severe, symptoms begin a few weeks earlier than usual, and bother them for longer periods of time,” says allergist Dr. Thanai Pongdee, who practices at
the Mayo Clinic, Jacksonville, Fla., and sees patients not only from the southern region of the U.S., but also from the East Coast and parts of the Midwest. “It doesn’t seem to matter where they’re from.”
 
Some studies have already shown that milder temperatures are indeed creating a little bit of allergy hell for sufferers.
 
A study published in the Proceedings of the National Academy of Science last year showed a link between a longer ragweed season and warming temperatures. According to the researchers, in some areas, ragweed season is 13 to 27 days longer than in was in 1995, attributed mostly to a later onset of a first frost. In another study presented at the 2010 Annual Meeting of the American Academy of Allergy, Asthma & Immunology, researchers found that from 1981 to 2007 there was an increase in the duration of some pollen seasons due to an increase of average temperatures.
 
Allergy sufferers in Georgia are already rubbing their itchy eyes. “We’re getting patients in already who are having allergic type symptoms, and we think it’s a cold, but as high as the pollen levels have been on some days, it may well be from the pollen,” says allergist Dr. Andy Nish, of Gainesville, Ga.  Since they’ve had such a mild winter – just like most of us – Nish expects a longer growing season, giving rise to larger amounts of pollen in the air, for a lengthier time.
 
That’s a problem, since those lucky folks who don’t usually experience allergy symptoms may be at increased risk due to these longer exposure times and heavier pollen loads, says the Mayo Clinic’s Pongdee.
 
Even in Cleveland, Ohio, known for its notoriously cold, long winters, this season’s mild temperatures have doctors gearing up for an earlier arrival of itchy-eyed patients. “I’m expecting allergies to be worse due to the unusual weather,” says allergist Dr. Samuel Friedlander, of University Hospitals Case Medical Center. “I had a patient report seeing a bee flying around this month, so perhaps even bee allergies may occur early.”
 
There’s no need to panic and buy a biohazard suit.
 
Doctors say the majority of patients can be helped with either over-the-counter or prescription medication, and some common-sense preventive measures like keeping windows closed when pollen counts are high. You can always check pollen counts at aaaai.org.

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