News in brief - Dec. 20, 2004

Teens and pertussis - Stronger Accutane safeguards - HIV testing higher among targeted populations - Drinking water could benefit those with low blood pressure

Teens and pertussis

An international group of pertussis researchers is recommending that adolescents and some adults be vaccinated against whooping cough to help prevent transmission to infants. The Global Pertussis Initiative made the recommendation in the Dec. 15 Clinical Infectious Diseases.

Worldwide, about 300,000 people -- mostly infants -- die each year from whooping cough. While vaccinations prevent infections for a few years, immunity declines if booster shots aren't administered later in life. A recent upswing in pertussis infection among teenagers and adults has been noted in many parts of the United States.

The initiative made several recommendations to help control the disease. The group's goal for North America is to enhance immunity by introducing universal adolescent vaccination programs and by vaccinating certain target groups, such as parents and relatives of newborns, health care workers and childcare workers.

A new pertussis vaccine suitable for teenagers and adults was developed about five years ago. "Now's the time to actually start using it," said Kevin Forsyth, MD, PhD, lead author of the study and chair of the pediatrics department at Flinders Medical Center in Adelaide, Australia.

Stronger Accutane safeguards

The Food and Drug Administration began strengthening the risk management plan that was already in place for Accutane, or isotretinoin, to try to further reduce the risk of congenital anomalies associated with fetal exposure to the drug.

The System to Manage Accutane Related Teratogenicity, or the SMART program, was one of several similar programs all designed to prevent fetal exposure.

An FDA advisory committee determined last February that the multiple programs could cause confusion and inadvertently allow a patient to take Accutane without being counseled on its dangers. The committee recommended that changes be considered.

The new program, which will go into effect in July 2005, will require registration of not only the physicians who prescribe the drug but also the pharmacies that dispense it and the patients who use it. The program will also require that a negative pregnancy test be obtained from all women who could become pregnant before they take the drug.

A single, centralized registry is to be developed to link prescribers, patients and pharmacies, according to the FDA. Privacy was of critical concern in devising the system, the agency noted.

HIV testing higher among targeted populations

Approximately 38% of Americans have been tested for HIV, with 10% to 12% of people being tested for HIV in 2002. These rates are higher for those more likely to test positive for the virus, according to a paper in the Dec. 3 Morbidity and Mortality Weekly Report.

Approximately a quarter of those with at least one risk factor such as hemophilia, being a man who has sex with men, using injection drugs, or trading sex for money or drugs have been tested. Also, about half of all pregnant women have been tested. The majority of this testing was provided by physicians and health care practitioners with only about 5% being administered at home.

The Centers for Disease Control and Prevention estimates that 25% of those who have the virus are not aware they are carriers.

Also, according to a separate report in the same issue of the MMWR, the number of new HIV diagnoses has remained steady with just more than 125,000 new cases reported in the 32 states with confidential name-based reporting, although it was higher among some groups. The rate for men increased by 5% from 2000 to 2003. More than half of new diagnoses were among African-Americans, and the rate for African-American women was 19 times that of white women.

Drinking water could benefit those with low blood pressure

Ingesting approximately 16 ounces of water could cause a rise in blood pressure sufficient to steady those with hypotension who faint while standing, according to a paper published in the December Journal of Neurology, Neurosurgery and Psychiatry.

Researchers at Imperial College London and St. Mary's Hospital in England measured the blood pressure of 14 patients with autonomic failure while they were lying down and standing.

Authors of the paper found that water could raise blood pressure in five to 13 minutes and that associated symptoms such as fainting were reduced or eliminated.

"This surprising discovery that water can have such an effect on blood pressure could help us to treat both sufferers of autonomic failure, and many people who suffer from low blood pressure generally, especially those who faint," said Dr. Christopher Mathias, senior author and clinical professor in the division of neurosciences and psychological medicine.