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CDC, Infectious Disease, Pediatrics, Public Health, Research

“Herd immunity” causes dramatic drop in infant chicken pox

In the early 1990s, Stanford scientist Ann Arvin, MD, led research that helped explain immune responses to varicella zoster, the virus that causes chicken pox. Her work contributed important scientific background for introducing the chicken pox vaccine.

Now a new study from the Centers for Disease Control examines how widespread use of this vaccine has protected infants too young for the chicken pox shot. The new paper is a stunning example of the power of “herd immunity” – the ability of broadly-used vaccination to protect those who are too fragile to be vaccinated themselves. The vaccine consists of a live but weakened version of the varicella virus, and is not safe to give until 12 months of age.

The study’s key finding is that chicken pox cases in infants dropped a whopping 90 percent between the vaccine’s 1995 introduction and 2008, the most recent year for which data were available. This is a big deal because in babies chicken pox can be quite severe. In the pre-vaccine era, death rates among infected infants were four times higher than among children who contracted chicken pox between ages 1 and 14.

Continued efforts to improve and expand varicella vaccination programs are well worth it, the study concludes. Some babies are still being exposed to chicken pox via unvaccinated or under-vaccinated older children, supporting the need to broaden “catch-up” programs that deliver a second dose of the vaccine to kids who have gotten only one of the two recommended doses. Babies can also catch chicken pox from adults who suffer shingles, a re-activation of the virus in the body of someone who had chicken pox years before, so shingles vaccination for adults should be expanded, too.

Previously: Vaccination could eliminate chicken pox-related deaths in the U.S.

Cancer, CDC, In the News, Pediatrics, Public Health, Sexual Health

Experts weigh in on recommendation that boys be given HPV vaccine

Experts weigh in on recommendation that boys be given HPV vaccine

As you may have heard yesterday, the CDC’s Advisory Committee on Immunization Practices is recommending that all preteen children, not just girls, get the HPV vaccine. The hope among public health experts is that widespread vaccination will lead to immunity to the virus and, eventually, cut rates of certain types of cancer.

In today’s San Francisco Chronicle, writer Erin Allday explores the issue and discusses some parents’ concerns with the vaccine:

…Pediatricians say there’s been clear discomfort among parents of preteen daughters to give their children a vaccine to prevent a sexually transmitted disease. The current political climate – with controversy in Texas over making the vaccine mandatory, and misleading comments from a potential presidential candidate about possible side effects – hasn’t helped, they said.

[Stanford's Paula Hillard, MD,] said some doctors, in talking to parents, are choosing to emphasize the vaccine as a tool to prevent cancer, glossing over the role of HPV. “The messaging is important,” she said. “And cancer prevention may be an easier message for parents than STD prevention.”

Still, she said, parents of preteen girls will often tell her they want to wait a little longer to vaccinate their children.

“The one thing I hear over and over again from parents is, ‘We’ll give it to her when she goes off to college,’ Hillard said. “Our current statistics are 50 percent of 17-year-olds have had intercourse. College may be too late. But parents don’t want to think too much about that.”

Hillard, who specializes in adolescent gynecology, told me yesterday that she strongly endorses the vaccine for both girls and boys.

Previously: Only one-third of teenage girls get HPV vaccine to prevent cervical cancer
Photo by alviseni

CDC, Humor, Public Health

CDC wants you to prepare for a zombie pandemic

Earlier this year, the Centers for Disease Control and Prevention (CDC) posted a blog entry outlining how you can prepare for a zombie apocalypse. The post proved to be tremendously popular and spurred the CDC to launch a contest for members of the public to submit 60-second videos showing how they’re preparing for a range of emergencies situations.

Now the government agency has introduced a graphic novel titled “Preparedness 101: Zombie Pandemic” to demonstrate  in an entertaining way the importance of being prepared. According to a recent USA Today story:

The comic begins with a couple, Todd and Julie, watching a news story about a strange virus that causes slow movement, slurred speech and violent tendencies. The newscaster says the CDC recommends the public avoid those with symptoms, gather emergency supplies and make an evacuation plan.

Todd checks the CDC’s website where he finds information about the new zombie virus and a list of items he’ll need for an emergency-preparedness kit. Just then, an infected zombie neighbor shows up at the door and tries to attack him.

The scene shifts to the CDC, where scientists are working around the clock to create a vaccine. In a cameo appearance, [Ali Kahn, director of the CDC's Office of Public Health Preparedness and Response] barks, “No, tell CNN I’ll call them back later…” into a phone as a Dr. Greene calls the Strategic National Stockpile to prepare to release its supplies of medicine.

Todd and Julie make it to a shelter, where trucks of vaccine arrive just as a horde of the undead crash through the doors.

To find out if Todd and Julie survive the zombie pandemic, download the full graphic novel here.

Previously: The CDC wants to help you prepare for the zombie apocalypse and CDC launches video contest for the zombie apocalypse
Photo by heather buckley

Cancer, CDC

Lung cancer rates declining in the U.S.

Some good news out of the CDC today: The rates of lung cancer among men in the United States decreased in 35 states between 1999 and 2008. And though the rates among women during that time period decreased in only six states (including California), the number of cases among women fell nationwide between 2006 and 2008. What’s more – and not surprisingly – states’ smoking patterns and anti-smoking efforts appear to play a role in cancer rates:

The decrease in lung cancer cases corresponds closely with smoking patterns across the nation. In the  West, where smoking prevalence is lower among men and women than in other  regions, lung cancer incidence is decreasing faster. Studies show declines in lung cancer rates can be seen as soon as five years after smoking rates decline.

The report also noted that states that make greater  investments in effective tobacco control strategies see larger reductions in smoking; and the longer they invest, the greater the savings in smoking–related health care costs. Such strategies include higher tobacco prices, hard–hitting media campaigns, 100 percent smoke-free policies, and  easily accessible quitting treatments and services for those who want to quit.

Previously: Study shows anti-tobacco programs targeting adults also curb teen smoking and A conversation about the FDA’s new graphic health warnings for cigarettes
Photo by andyket

CDC, Infectious Disease, Nutrition

Slight decrease in food-borne illnesses, reports CDC

Slight decrease in food-borne illnesses, reports CDC

On the heels of the U.S. Food and Drug Administration announcement introducing pilot programs to improve methods of identifying sources of tainted food, comes news from the Centers for Disease Control and Prevention that the latest data shows a decline in food-borne outbreaks and related illnesses.

The national food safety report card includes details on the more than 1,000 outbreaks of food-borne disease from 2008, the most recent year information is available. WebMD reports:

The outbreaks caused 23,152 cases of illness, nearly 1,300 hospitalizations, and 22 deaths. But because most food-borne illnesses go unreported, the actual numbers are much higher. The CDC estimates that contaminated food causes as many as 48 million illnesses annually.

According to the CDC, a food-borne outbreak occurs when two or more cases of a similar illness are caused by a common food. An average of 24 such outbreaks were reported from each state or territory in 2008.

The total number of outbreaks was 10% less than the average number reported from 2003 to 2007. The number of outbreak-related illnesses in 2008 was also lower, by 5%.

Overall, Salmonella (pictured above) lead the pathogen pack in causing the most illnesses and deaths. The CDC offers several tips for preventing food contamination by Salmonella or other bacteria.

Previously: FDA introduces pilot programs to improve methods of identifying foodborne illness sources, USDA to launch campaign on food safety, List grades best and worst states for food poisoning, Report shows high costs of foodborne illnesses and Image of the Week: The public health costs of Salmonella
Photo by News21-usa

CDC, In the News, Parenting, Patient Care, Pediatrics, Public Health, Women's Health

More breastfeeding support needed in hospitals

More breastfeeding support needed in hospitals

Just in time for World Breastfeeding Week (yes, there is one), the CDC has released a report (.pdf) showing that only a small percentage of U.S. hospitals – 4 percent - provide the necessary support for breastfeeding moms. Among the other bleak findings, as reported by Healthwatch:

• Almost 80 percent of hospitals give formula to healthy breastfeeding infants when it isn’t medically necessary, which the CDC says “makes it much harder for mothers and babies to learn how to breastfeed and continue breastfeeding at home”;

• Only 14 percent of hospitals have a written, model breastfeeding policy;

• Only one-third of hospitals practice rooming in, whereby mothers and babies stay together 24 hours a day; and

• Almost 75 percent of hospitals don’t provide mothers and babies the support they need when they leave the hospital, including a follow-up visit, a phone call from hospital staff and referrals to lactation consultants, Women Infants [and] Children and other support systems in their community.

The report, which follows a White House announcement that health plans will soon be required to provide women with no-cost breastfeeding services and counseling, spells out a clear need for better in-hospital support for new moms. (Public support is something to be worked on, too – but let’s take baby steps, shall we?)

The CDC goes on to outline ten ways for institutions to help ensure successful breastfeeding (among them: have a breastfeeding policy that is routinely communicated to staff, practice “rooming in” for moms and their babies, and encourage feeding on demand), and I hope medical professionals will pay attention and help remove the barriers facing  patients who want to breastfeed.  I also hope – though I’m not holding my breath – that when breastfeeding hits the headlines from now on, the focus won’t be on the trivial. After all, protecting children against illness and lowering our country’s health-care costs is pretty serious business.

Previously: Surgeon general calls for more breastfeeding support, Breastfeeding called a “secret weapon to save billions of dollars” and Free formula may discourage moms from breastfeeding exclusively
Photo by myllissa

CDC, Health Policy, Infectious Disease, Pediatrics, Public Health, Research

Vaccination could eliminate chicken pox-related deaths in the U.S.

Vaccination could eliminate chicken pox-related deaths in the U.S.

Chicken pox is, traditionally, temporarily uncomfortable for kids and troublesome for parents. But in some rare cases, it’s much more: Varicella (chicken pox’s scientific name) can lead to infections and pneumonia in otherwise healthy children and adults, and a small but significant number of people die each year.

Luckily, vaccination – this fairy tale’s hero – has just about vanquished varicella’s villainous virus, according to a CDC study published today in Pediatrics. 

For the study, the researchers tracked deaths by varicella since the introduction of the vaccine in 1995. In 2007, there were 14 directly varicella-related deaths in the United States, as opposed to an annual average of 105 in the four years leading up to the vaccine’s introduction. In 2006, the CDC suggested that a second dose of the vaccine could completely eliminate varicella deaths in the country.

Previously: The cost of forgoing routine vaccinations
Via Health Blog

CDC, FDA, Infectious Disease, Public Health

FDA announces this year’s approved flu vaccines

Influenza may not be the first thing on your mind on this sunny summer Monday, but it’s not too early to start thinking about the coming flu season. This morning, the FDA announced it has approved the 2011-2012 vaccines to be distributed in the United States:

Vaccination remains the cornerstone of preventing influenza, a contagious respiratory disease caused by influenza virus strains. The vaccine formulation protects against the three virus strains that surveillance indicates will be most common during the upcoming season and includes the same virus strains used for the 2010-2011 influenza season.

Influenza leads to more than 200,000 hospitalizations per year in the US, according to the CDC. The FDA encourages health-care personnel in particular to get vaccinated this flu season.

CDC, Humor, Public Health

CDC launches video contest for the zombie apocalypse

Apparently the Centers for Disease Control and Prevention zombie apocalypse post I wrote about earlier this week – the one written by Rear Admiral Ali Khan, MD, MPH – was quite popular: Health Blog is reporting the entry got some 1.2 million page views as of earlier this afternoon. And now:

. . .the CDC is following up Khan’s message with a video contest. The agency is asking people to create 60-second videos showing how they’re preparing for any emergency (“hurricanes, floods, tornadoes, zombies”) and send them to by June 3. Winners will be chosen by the “CDC Zombie Task Force.”

How I’d love to be a member of the CDC Zombie Task Force.

Previously: The CDC wants to help you prepare for the zombie apocalypse

CDC, Humor, Public Health

The CDC wants to help you prepare for the zombie apocalypse

This is is an extremely clever way to get people to read a disaster preparedness plan: The Centers for Disease Control and Prevention recently posted a blog entry outlining how you can prepare for a zombie apocalypse. Rear Admiral Ali Khan, MD, MPH, begins:

There are all kinds of emergencies out there that we can prepare for. Take a zombie apocalypse for example. That’s right, I said z-o-m-b-i-e a-p-o-c-a-l-y-p-s-e. You may laugh now, but when it happens you’ll be happy you read this, and hey, maybe you’ll even learn a thing or two about how to prepare for a real emergency.

In addition to offering some practical advice (which is, of course, useful in other disasters too), he outlines what the CDC would do in such a situation:

If zombies did start roaming the streets, CDC would conduct an investigation much like any other disease outbreak. CDC would provide technical assistance to cities, states, or international partners dealing with a zombie infestation. This assistance might include consultation, lab testing and analysis, patient management and care, tracking of contacts, and infection control (including isolation and quarantine). It’s likely that an investigation of this scenario would seek to accomplish several goals: determine the cause of the illness, the source of the infection/virus/toxin, learn how it is transmitted and how readily it is spread, how to break the cycle of transmission and thus prevent further cases, and how patients can best be treated. Not only would scientists be working to identify the cause and cure of the zombie outbreak, but CDC and other federal agencies would send medical teams and first responders to help those in affected areas (I will be volunteering the young nameless disease detectives for the field work).

Nicely done, Dr. Khan.

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