Traveling Children Should Get Japanese Encephalitis Vaccine

Fran Lowry

Jun 19, 2013

 

Children aged 2 months through 16 years should be vaccinated against Japanese encephalitis (JE) if they are going to be traveling to areas that are endemic for the disease.

A panel of 15 immunization experts convened by the Centers for Disease Control and Prevention (CDC), in Atlanta, voted unanimously to add the younger age group to the existing recommendations for travelers aged 17 years or older, which were made in 2009.

The request to add young children to the recommendations was put before the CDC's Advisory Committee on Immunization Practices (ACIP) by Marc Fischer, MD, medical epidemiologist with the CDC’s Arboviral Diseases Branch in Fort Collins, Colorado.

Fatal Disease With No Treatment

Japanese encephalitis is endemic to Asia and the Western Pacific and is transmitted by mosquitoes.

"There is no treatment for Japanese encephalitis and it is fatal in 20 to 30 percent of people who get the infection, and about a third to a half of the survivors have some neurologic, cognitive or behavioural sequelae," Dr. Fischer told Medscape Medical News.

He presented data to the ACIP panel that demonstrated that the JE vaccine, which was licensed for use in children aged 2 months or older in May of this year, is safe and effective.

The vaccine is marketed by Novartis as IXIARO.

"This is a safe vaccine, it has a low incidence of serious adverse events and in the studies that we reviewed, which included 3 in children and 9 in adults, the serious adverse events were similar to those seen in Prevnar and Havrix, the comparison vaccines," Dr. Fischer said.

In the period between 1973 and 2012, there have been 65 cases (59 adults, 6 children) of JE among US travelers.

Eleven (19%) adults and 2 (33%) children died, 25 (42%) adults and 3 (50%) children survived with sequelae, and 15 (25%) adults and zero children had no sequelae. Details of the remaining 8 adults and 1 child are unknown, Dr. Fischer said.

Itineraries for 47 of the travel-associated cases revealed that the majority (30, or 64%) had a travel duration of 1 month or more, 13 (27%) traveled for 2 to 4 weeks, and 4 (9%) traveled for 1 to 2 weeks.

There were no cases of JE reported in short-term travelers visiting urban areas only. However, travel to rural areas was dangerous, with 17 individuals getting infected.

Relative Risk Is Low

The JE disease risk for most travelers is very low and varies on location, duration of travel, the season, and travel activities, Dr. Fischer said.

In addition, the vaccine, although safe and effective, is very expensive.

"These are all factors to be taken into account when making recommendations for who gets vaccinated," he said.

Vaccinating children living in endemic areas is cost-saving, but the JE vaccine for all travelers to Asia would not be cost effective, he said.

"Over 5 and a half million Americans travel to Asia each year, and the overall risk of Japanese encephalitis is low, less than 1 case per million travelers. Also, the cost of the vaccine is high, at $200 to $250 a dose. For some travelers, even a low risk of serious adverse events due to the vaccine may be higher than the risk for disease. Because of these factors, we think the JE vaccine should be targeted to travelers who are at increased risk for disease based on their planned itinerary," Dr. Fischer said.

Including Kids the Only Change

The current recommendations for vaccination stand, with the only addition the inclusion of children aged over 2 months.

As confirmed by the ACIP panel, these are as follows:

• The JE vaccine is recommended for travelers who plan to spend a month or longer in endemic areas during the JE virus transmission season. This includes long-term travelers, recurrent travelers, or expatriates who will be based in urban areas but are likely to visit endemic rural or agricultural areas during a high-risk period of JE virus transmission (Recommendation category A)
• The JE vaccine should be considered for short-term (less than1 month) travelers to endemic areas during the JE virus transmission season if they plan to travel outside of an urban area and have an increased risk for JE virus exposure (eg, spending substantial time outdoors in rural or agricultural areas, participating in extensive outdoor activities, staying in accommodations without air conditioning, screens, or bed nets). The JE vaccine should also be considered for travelers to an area with an ongoing JE outbreak and those traveling to endemic areas who are uncertain of specific destinations, activities, or duration of travel (Recommendation category B).
• The JE vaccine is not recommended for short-term travelers whose visit will be restricted to urban areas or times outside of a well-defined JE virus transmission season (Recommendation Category A).

Dr. Fischer has disclosed no relevant financial relationships.

CDC's Advisory Committee on Immunization Practices Meeting: June 19, 2013.

Pediatric CT Scans Raise Future Cancer Risk

Ricki Lewis, PhD

Jun 10, 2013

 

The number of computed tomography (CT) scans of the head, abdomen/pelvis, chest, or spine performed on children younger than 14 years has risen dramatically since 1996, elevating radiation-induced cancer risk, according to studypublished online June 10 in JAMA Pediatrics.

Children are particularly sensitive to radiation, and their age allows many years for cancers to develop. CT scans deliver 100 to 500 times higher doses of ionizing radiation than conventional X-rays, and several studies have linked these doses to elevated cancer risk.

Diana L. Miglioretti, PhD, from the University of California, Davis, and colleagues conducted a retrospective observational study to quantify trends in pediatric CT use in 6 diverse US healthcare systems. They evaluated 4,857,736 child-years and calculated radiation doses for a random sample of 744 scans. The body regions studied account for 95% of pediatric CT scans.

Outcomes were rates of CT use, doses, and projected lifetime attributable risks of cancer.

From 1996 through 2005, CT use doubled for children younger than 5 years and tripled for children aged 5 to 14 years. Rates stabilized in 2006 and 2007 and have declined since then.

Effective doses varied widely, from 0.03 to 69.2 mSv per scan. From 14% to 25% of abdomen/pelvis scans received an effective dose of 20 mSv or higher, as did between 6% and 14% of spine scans and from 3% to 8% of chest scans.

Younger patients and girls face higher projected lifetime attributable risk for solid cancers than older patients and boys. The researchers calculated that for girls, 300 to 390 abdomen/pelvis scans would cause a single radiation-induced solid cancer, whereas 670 to 760 of such scans would do so for boys. Risks were highest for CT scans to the abdomen/pelvis or spine.

Leukemia risk was highest for head CTs on young children. The risk decreased from 1.9 cases per 10,000 scans for children younger than 5 years to 0.5 cases per 10,000 scans for children aged 10 to 14 years. Among the older children, leukemia risk was highest for abdomen/pelvis scans (1.0 cases per 10,000 scans).

Theoretically, the approximately 4 million pediatric CT scans performed in the United States each year to the specified body parts will cause approximately 4870 cancers. The researchers estimate that lowering the highest 25% of doses to the median could prevent 43% of the projected radiation-induced malignancies, but reducing the highest 50% of doses would only prevent an additional 8% of cancers.

The investigators call for further research to identify situations in which CT scans of children improve health outcomes and are the most effective diagnostic method. They conclude, "Implementation of...readily available dose-reduction strategies, combined with the elimination of unnecessary imaging, could dramatically reduce future radiation-induced cancers from CT use in pediatrics."

A limitation is that the assessment may have underestimated cancer risk projections because the protocol counted some multiple scans performed on a single day as 1 scan and considered only cancers with published predictive models.

This study was supported by the Cancer Research Network Across Health Care Systems and the National Cancer Institute. The authors have disclosed no relevant financial relationships.

JAMA Pediatr. Published online June 10, 2013. Abstract

Probiotics and Prebiotics in Preventing Food Allergy and Eczema

Mikael Kuitunen

Curr Opin Allergy Clin Immunol. 2013;13(3):280-286. 

 

Abstract and Introduction

Abstract

Purpose of review To describe the current literature on clinical trials of probiotics for eczema and food allergy prevention in view of recent new approaches and long-term follow-ups.

Recent findings Attempting allergy prevention by probiotic administration has been most successful when assessing atopic eczema, the most prevalent allergic disease at an early age. More than half of the published studies demonstrate a decrease in eczema prevalence until 2 years, whereas the remaining studies fail to show an effect. Effects have been most consistent with combined prenatal and direct postnatal supplementation of the infant and appear strain-specific, with Lactobacillus rhamnosus most often showing an effect. Prenatal-only and postnatal-only studies often fail to show effects. Recent long-time follow-ups have shown promising but not consistent results. A very recent follow-up of a large well conducted cohort shows that long-term effects of eczema prevention persists until age 4 and prevention of respiratory allergies might also be possible.

Summary Prevention of eczema with probiotics seem to work until age 2 years and extended effects until 4 years have been shown in high-risk for allergy cohorts. Effects are strain-specific, with L. rhamnosus showing the most consistent effects especially when combining pre and postnatal administration.

Introduction

The increase in allergic diseases has been linked to the relative lack of microbial stimulation, especially in early childhood when the permeability of the gut is higher and the gut immune system is not fully developed. A recent understanding is the coevolution of the human species and the metagenome. The diversity of the microbiome and its contribution to the development of allergic and autoimmune diseases has gained much attention. The body's largest immune system residing in the gut is complexly stimulated by the gut microbiome, which is considered central when evaluating the hygiene hypothesis, now rephrased as the micoflora hypothesis of allergic diseases. New molecular techniques enable broader analysis of microbiota and the microbiome.

Development of oral tolerance requires contacts with microbes.A low diversity of gut microbiota during the first months has been associated with development of atopic eczema. Mice reared in germ-free environments do not develop tolerance, but this can be reconstituted with the administration of bifidobacteria. Further, less lactobacilli and bifidobacteria have been shown in the gastrointestinal tract of infants developing allergy later. This led to the probiotic concept.

Supplementing microbes using probiotics, health-promoting nonpathogenic bacteria in an attempt to prevent allergies is a well tolerated alternative. Twenty-three randomized, placebo-controlled intervention studies regarding the clinical effect of probiotic supplementation on development of allergy and eczema in particular have been published. Eczema is the most prevalent allergic disease in early childhood and fairly easy to diagnose reliably using well defined validated criteria and a reliable marker of allergic disease being a significant risk factor for developing respiratory allergies later. Many studies also report on the prevention of food allergy, but its prevalence is significantly less than that of eczema. Around 60% of the studies show a favourable effect decreasing the risk of eczema during the first years of life. The remaining studies fail to show an effect. Most investigators have chosen high risk for allergy cohorts to study the probiotic preventive capacity. This review highlights recent work on prevention of eczema and food allergy using probiotics. Since the publication of earlier reviews on prevention and treatment of allergic diseases, several large prevention studies have been published that are the focus of this review.

Baby Matters Recalls Recliner Linked to Infant Deaths: U.S. Agency

Reuters Health Information

Jun 14, 2013

 

WASHINGTON (Reuters) Jun 14 - Baby Matters LLC is recalling baby recliners linked to five infant deaths as part of a settlement with the Consumer Product Safety Commission, the U.S. agency said on Friday.

The settlement calls for the company, based in Berwyn, Pennsylvania, to recall its foam rubber Nap Nanny and Nap Nanny Chill infant recliners and their covers, in exchange for the CPSC dropping an administrative complaint that it filed in December 2012, the agency said in a statement.

Four infants have died in the Nap Nanny Generation Two recliners, and a fifth death involved the Chill model, the agency said.The CPSC also received 92 reports of infants hanging or falling over the side of the recliners, including some children who were restrained in the product's harness.

The agency urged consumers to stop using Nap Nanny and Nap Nanny Chill recliners. It said Baby Matters was no longer in business and was not accepting returns.

About 165,000 of the Nap Nanny and Chill products were sold between 2009 and 2012 for about $130 each.

In December 2012, Amazon.com Inc, Buy Buy Baby Inc, Diapers.com, and Toys R Us/Babies R Us announced a voluntary recall of Nap Nanny and Chill models sold in their stores.

Consumers who bought a Nap Nanny from one of those retailers should contact them for information on receiving a refund, the CPSC said.

"CPSC urges other consumers to immediately dispose of the products to ensure that they are not used again," the statement said.

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