Updates

UPDATES

Much ado about vaccines

In the United States, progress in immunizing children against infectious diseases is--most of the time--straightforward, and the rewards in preventing disease are enormous. Last month's announcement by the CDC of the virtually total annihilation of measles in the US is a case in point. But occasionally the forward motion hits a snag. In August, there were two:

Hold the Rotashield. Responding to the CDC's request that Rotashield immunization be suspended until more data on a suspected connection with intussusception are available, the AAP's Committee on Infectious Disease has issued interim recommendations (Pediatrics 1999;104[3]:575). Clinicians are advised to suspend rotavirus vaccination of unimmunized or partially immunized children, teach parents of recently immunized children to recognize the signs and symptoms of intussusception, and report cases of intussusception that occur after vaccination to the vaccine adverse-event reporting system (VAERS), at 800-822-7967.

Get rid of the mercury. In this case, the problem is thimerosal, a preservative used in many vaccines to prevent bacterial contamination. Unfortunately, thimerosal is almost half mercury, and mercury is dangerous to the developing brain of very young infants. The Food and Drug Administration has recently determined that infants who receive thimerosal-containing vaccines at several visits may be exposed to more mercury than federal guidelines on mercury exposure recommend. The good news is that neither IPV nor OPV contain any thimerosal, nor do the MMR, varicella, rotavirus, or Lyme disease vaccines. Several Hib products that do not contain thimerosal are also available. The bad news is that all whole cell DTP vaccines and most acellular DPT vaccines do; the exception is Infanrix, which is thimerosal-free. Both hepatitis B vaccines, Engerix-B and Recombivax HB, also contain the preservative.

So what to do? The AAP Committees on Infectious Disease and Environmental Health believe that missed immunizations pose a far more serious danger to children than mercury in the amounts they may be exposed to by vaccination (Pediatrics 1999;104(3): 570). Therefore, the most important thing clinicians can do is follow the routine immunization schedule, using thimerosal-free vaccines when they are available. If these vaccines are scarce, clinicians should save them for premature infants and continue to use the thimerosal-containing vaccines until substitutes are available. For further protection, the initial HBV immunization for infants of HbsAg­negative mothers should be delayed until 6 months of age. Meanwhile, vaccine manufacturers and the FDA are urged to work together to reduce or eliminate mercury-containing preservatives in vaccines.

Happily, the bad press inspired by these two events is unlikely to slow the pace of vaccine development. Vaccine products now in the pipeline include new combinations of inactivated poliovirus vaccine (IPV) with DtaP, HBV, and Hib vaccines, as well as a conjugate meningococcus vaccine--all in stage three, large-scale trials. A conjugate pneumococcus vaccine has completed stage three trials and is awaiting FDA licensure.

Recalls

Several products that could pose dangers to children were recalled last month:

Crazy Ribbon and Crazy String, sold in party stores as birthday party entertainment for children. The manufacturers have recalled more than 900,000 cans after string sprayed near an open flame caught fire and seriously burned a child.

More than half a million self-injection kits for treating severe allergic reactions. Wyeth-Ayerst Laboratories, which manufactures the epinephrine used in the kits, said that routine quality-control tests had shown the drug was not as potent as it was supposed to be. The recalled products include the Insect Sting Treatment Kit packaged by Derm/Buro Inc., and the Hollister Stier-Ana kit and AnaGuard, packaged by Bayer Corporation.

Sensational Gourmet chocolate chip cookies, recalled because the label does not list pecans--which may be in some batches--as an ingredient. The cookies, which could pose a danger to children allergic to nuts, were sold in stores in CT, MD, MA, NJ, NY, OH, PA, RI, VA, and WV.

AIDS and the world's children

AIDS deaths continue to decline in the US, although not as rapidly as they were declining a few years ago. But the story is very different in the Third World, especially in Africa. According to the United Nations Children's Fund (UNICEF), AIDS is a major cause of mortality for children under 5 in many African countries, and is expected to remain such for some time (see graph). AIDS in adult caretakers also has tremendous repercussions for children, causing losses of family income that put surviving children at great risk of malnutrition, illiteracy, and disease.

In Africa, also, teenage girls appear to be particularly vulnerable to HIV infection, far more so than their male peers. In a recent study in western Kenya, for example, 25% of girls between the ages of 15 and 19 were found to be HIV positive, compared to 4% of boys in the same age group. These gender discrepancies, according to UNICEF, reflect the greater social and physical vulnerability of girls in African society and also indicate that girls are more likely to be infected by older men than by boys their own age.
The upswing in adolescent HIV infection is not limited to Africa; infection rates among teens--especially girls--are also rising in North America and Europe. In Eastern Europe and Central Asia, the proliferation of IV drug use has spurred the epidemic among teens.

There are some signs of hope: Educational programs have succeeded in reducing rates of infection in Uganda, where prevalence rates among 15- to 19-year-olds dropped from 38% in 1991 to 7.3% in some areas in 1996. And a new drug regimen developed by researchers in the US and Uganda--a single dose of nevirapine for a mother during labor and one for her newborn by the third day of life--shows great promise in preventing HIV transmission from mother to infant. The total cost for the nevirapine treatment of mother and newborn is $4. At that price, it may be possible for the first time for poor countries to institute wide-scale use of a treatment known to prevent one route of HIV transmission.

Emergency contraception: Still hard to get

The Preven emergency contraception kit that recently came on the market contains everything a teenager who has had unprotected intercourse needs: a urine pregnancy test, an information guide, and four blue tablets each containing 50 mcg of ethinyl estradiol and 0.25 mg of levonorgestrel (Contemporary Pediatrics 1999;16:59). While not the only available source of emergency contraception, the kit seems well suited for adolescent use. But pediatricians thinking of writing a script for Preven should warn teenage patients that not every pharmacy carries it. Wal-Mart, for example, refuses to fill Preven prescriptions, although the company says Wal-Mart pharmacists will refer customers with Preven prescriptions to other pharmacies. According to a survey conducted by the American College of Obstetricians and Gynecologists in Philadelphia several months after FDA approval of Preven, 71% of pharmacies surveyed did not carry it and many pharmacists were unaware of the product's existence.

Now another product that may meet teenagers' needs is available. The FDA has approved a POP (progestin-only pill) called Plan B. The Plan B package contains two 0.75 mg levonorgestrel tablets, one to be taken within 72 hours of unprotected intercourse and the second 12 hours after the first. In clinical trials, Plan B proved as effective in preventing pregnancy as the 4-pill Yuzpe regimen used in Preven, with only half as many users reporting adverse side effects of nausea and vomiting. Plan B is distributed by Women's Capital Corporation of Kirkland, WA.

Teenagers' drugs of choice

One way of tracking adolescent drug use is to check admissions to treatment facilities by age and primary substance. The Substance Abuse and Mental Health Services Administration (SAMHSA) has a data set on all such admissions to publicly funded facilities from 1992 to 1997. The 1997 data show that admissions for substance abusers age 17 or younger have risen, from 6.3% of all admission in 1993 to 8.9% in 1997. The favorite among these teens is alcohol, but marijuana is also high on their list. According to SAMHSA, teens 19 or younger accounted for half of all admissions for marijuana use and more than half the patients admitted for marijuana reported having used the drug by age 14. Next comes inhaled heroin, edging out smoked cocaine by a narrow margin. The percentage of heroin admissions for young people under the age of 20 was 3%. Then come stimulants, especially methamphetamine; admissions for stimulant abuse account for 5% of treatment admissions. A taste for methamphetamines is a regional thing, once limited to California but steadily spreading eastward as far as the Mississippi in the years covered by the survey.

These treatment data shed light on which drugs teen users prefer, but should be set into the context of larger trends in drug use. That context is provided by the recently released 1998 National Household Survey on Drug Abuse. The overall finding from the Household Survey is that illicit drug use among teens has leveled off; the most recent estimates are 9.9% of youths age 12 to 17 using illicit drugs, a statistically significant decrease from 11.4% of the year before, According to Drug Czar Barry McCaffrey, these findings indicate that efforts to reduce drug use among young people are on the right track. Educational materials to help in that effort are produced by the Department of Health and Human Services and SAMHSA. For free copies of Marijuana: What Parents Need To Know, Tips for Teens, and Keeping Youth Drug Free, call 800-729-6686 or access the National Clearinghouse for Drug and Alcohol Information, www.health.org.

Calendar

October 21­24, North American Society for Pediatric Gastroenterology and Nutrition, Denver, CO. To register, call NASPGN at 856-848-1000 or E-mail to naspgn@slackline.com

November 4­7, ADHD: Causes and Possible Solutions, Arlington, VA. For more information, E-mail Jacqueline Roberts at IRConsult@aol.com or call International Research Consultants at 703-998-6091

November 7­11, American Public Health Association, Chicago. To register, call 202-789-5670

November 18­21, Infectious Disease Society of America Annual Meeting, Philadelphia. For more information, call 703-299-0200

November 29­December 2, 14th National Conference on Chronic Disease Prevention and Control, Dallas, TX. For more information, send E-mail to cdcinfo@cdc.gov.

--Judith Asch-Goodkin

Contributing editor

EYE ON WASHINGTON

In the dog days of August, politicians flee the capital. Congress closes down for the summer recess, the President and the First Lady mix vacationing with fund-raising and promoting Mrs. Clinton's senatorial prospects, and presidential candidates of both parties hit the hustings. When Congress reassembles, their first order of business will probably be to send the Republican tax cut bill, passed just before the recess, to the White House. Then the President can veto it and the real horsetrading over what to do with budgetary surpluses can begin. The new session may also be able to tackle health-care reform and gun control legislation, problems the leadership was unable to resolve before the recess. Then again, members on both sides of the aisle may prefer to leave these issues dangling until after the election.

Meanwhile, the agencies of government continue to go about their business.

The Department of Health and Human Services has announced new measures to facilitate research into the medical uses of marijuana and its constituents. The Department created a process for providing research-grade marijuana on a reimbursable basis for approved clinical research, including projects other than those funded by the National Institutes of Health.

The Environmental Protection Agency banned use of the pesticide methyl parathion on fruit and vegetable crops, in the first instance of an EPA regulation specifically intended to protect children. The EPA was following a mandate in the 1996 Food Quality Protection Act, which upped the margin of safety the agency required by 10 times to compensate for the vulnerability of children to pesticide risks.

The Food and Drug Administration finalized regulations for over-the-counter sun protection products, specifying three categories for labeling: minimum, for sun protection factor (SPF) of 2 to 11; moderate, for SPF 12 to 29; and high, for SPF 30 or greater. Unsupported, absolute, or misleading terms such as "sunblock," "waterproof," and "all-day protection" are banned, and tanning products that do not contain sunscreen must warn users the product does not protect against harmful effects of sun exposure.

The Department of Agriculture's Food Safety and Inspection Service joined with the FDA to propose new egg regulations to protect consumers against Salmonella infection. Egg cartons must carry warning labels stating that eggs can contain harmful bacteria and instructing purchasers to keep eggs refrigerated, cook eggs until yolks are firm, and cook foods that contain eggs thoroughly.

Judith Asch-Goodkin. Updates. Contemporary Pediatrics 1999;10:13.