News in brief - Feb. 14, 2005

CDC takes steps to ensure use of remaining flu vaccine supplies - Aneurysm screening for men - Dietary fat -- the good and the bad - Increasing syphilis rates may be caused by bacterial factors

CDC takes steps to ensure use of remaining flu vaccine supplies

As the influenza vaccine season winds down and the flu season winds up, the Centers for Disease Control and Prevention endorsed the broadening of recommendations for who should receive the vaccine in areas with ample supplies.

The agency also made available 3.1 million doses in the federal government's emergency reserve to physicians and other health care providers and permitted the use of flu vaccine in the government's Vaccines for Children program for use by those not usually eligible for it.

These steps were taken because of increasing concern that limited vaccine supplies might not be used. The nation's expected vaccine supplies shrank significantly from nearly 100 million to 61 million in October, when Chiron Corp. announced that it would not be providing shots because of contamination problems.

"Too many people who are at high risk for the serious complications of influenza are not vaccinated, and, quite frankly, that is just tragic," said CDC Director Julie Gerberding, MD, MPH.

The 3.1 million doses are being turned over to Sanofi Pasteur, formerly Aventis Pasteur, to sell directly to those who provide shots. These doses can be administered to anyone who wants one, and, unlike most flu vaccine ordered this season, unused doses can be returned to the company for a credit.

The actions were praised by physicians for encouraging additional use of the vaccine.

"It is our hope that increased awareness of this new availability of the vaccine will encourage those who have not yet been vaccinated to protect themselves from the flu," said AMA Trustee Ronald M. Davis, MD.

Aneurysm screening for men

Men between the ages of 65 and 75 who are or have been smokers should have a one-time ultrasound to screen for abdominal aortic aneurysms, says a new recommendation from the U.S. Preventive Services Task Force. The recommendation is published in the Feb. 1 issue of the Annals of Internal Medicine.

This is the first time the task force has recommended such screening. New evidence shows that screening and surgery to repair large abdominal aortic aneurysms are effective at reducing the number of male deaths caused by this condition.

Estimates indicate that between 59% and 83% of patients with ruptured abdominal aortic aneurysms die before reaching the hospital and having surgery. Men age 65 or older who currently are or have been regular smokers are at the highest risk for abdominal aortic aneurysms. Although few studies have been conducted in women, the published research indicates that women are at low risk for aneurysms.

Each year, the condition causes about 9,000 deaths in the United States.

Dietary fat -- the good and the bad

The type of dietary fat consumed could be more important than total fat intake in reducing the risk of cardiovascular deaths, according to a study in the Jan. 24 issue of Archives of Internal Medicine.

Polyunsaturated fat has been recommended for several decades in the primary prevention of cardiovascular disease, but few studies had offered scientific support for the advice.

In the new study, Finnish researchers found that men who consumed higher levels of polyunsaturated fats were up to three times less likely to die of cardiovascular disease than men who consumed less.

"Carrying out recommendations to replace saturated fat with polyunsaturated fat in the primary prevention of cardiovascular diseases may substantially decrease cardiovascular disease and, to a lesser degree, overall mortality," the researchers concluded.

A separate study in the same Archives issue found that consuming tuna or other broiled or baked fish is associated with a lower risk of stroke in the elderly, while eating fried fish or fish sandwiches is linked to a higher risk.

Researchers identified a trend of 14% lower stroke risk with a consumption of broiled or baked fish one to three times per month. Eating broiled or baked fish one to four times per week, or five or more times per week, was associated with a respective 28% and 32% lower risk of ischemic stroke.

But fried fish and fish sandwich consumption was associated with a 37% higher risk of all types of stroke and a 44% higher risk of ischemic stroke.

Increasing syphilis rates may be caused by bacterial factors

Syphilis outbreaks could be caused by a 10-year cycle of increasing then waning immunity to the bacteria rather than changes in human behavior, according to a paper published in the Jan. 27 issue of Nature.

Public health officials long have been concerned about increasing syphilis rates for fear that they could be an indicator of increasing unsafe sex, which could, in turn, lead to increasing HIV incidence.

But researchers at the Imperial College London analyzed data from 68 U.S. cities since the 1940s and found that syphilis rates escalated every 10 years. Authors of the paper suspect that as immunity to syphilis in the population falls, the number of cases increases. Immediately after an epidemic, when immunity is at its highest, the numbers wane.

Authors suggested that this knowledge could lead to elimination of the disease.

"It may be possible to use these findings to help doctors and sexual health workers predict and prepare for future outbreaks of the disease," said Dr. Nicholas Grassly, lead author and professor of infectious disease epidemiology. "Troughs in the number of cases offer an unprecedented opportunity for eradication of the disease. However, when this opportunity is missed, an epidemic is likely to follow."

The paper also included data about gonorrhea but did not find the same cyclic pattern as syphilis. Authors suggest that this sexually transmitted disease might be a better marker of changes in behavior.