Flu Vaccine Only Mildly Effective in Elderly
The flu vaccine, a cornerstone of public health policy, is only mildly effective in the population for which it is supposedly most critical: the elderly.
According to a study appearing in the Sept. 22 online issue of The Lancet, vaccines against influenza are only "modestly effective" in people in long-term care facilities and even less effective for elderly people still living in the community.
That research is twinned with another flu study, which found more bad news: that resistance to drugs used to treat influenza has risen 12 percent in the past decade.
This finding, the authors stated, raises questions about the government's policy of stockpiling such drugs.
Strong opinions to the vaccine study came from all sides of the issue.
"The vaccine doesn't work very well at all," said study author Dr. Tom Jefferson, an epidemiologist with the Cochrane Vaccines Field in Rome. "Vaccines are being used as an ideological weapon. What you see every year as the flu is caused by 200 or 300 different agents with a vaccine against two of them. That is simply nonsense."
Dr. Marc Siegel, author of False Alarm: The Truth About the Epidemic of Fear, agreed. "We have set up a situation where a fear is created, and then we try to create the treatment for this fear. The public gets the idea that the flu is going to kill them and the vaccine will save them. Neither is true," he said. "The flu vaccine has use in cutting down on deaths from complications in the chronically ill and people at great risk, but it's not a panacea."
The U.S. Centers for Disease Control and Prevention responded strongly on the other side.
"We certainly do hope that people will not be sidetracked from this important point. There are studies that show that the vaccine is effective in preventing serious complications of the flu," said CDC spokesman Tom Skinner. "This is not going to change the fact that we each and every year recommend people in high-risk categories to get the vaccine."
Health officials worldwide, including those at the CDC, push to get as many elderly individuals as possible vaccinated against the flu each year. According to the study, in 2000, 40 of 51 developed or rapidly developing countries recommended vaccines for all individuals aged 60 and older. In 2003, 290 million doses of vaccine were distributed worldwide.
Earlier this month, U.S. health officials starting urging all eligible persons to get a flu shot, with priority given to the elderly and certain other groups. And to avoid last year's flu vaccine shortage, U.S. health officials have planned for a total of 97 million doses of vaccine.
The current study provided no new data but, rather, looked at 64 existing studies which looked at the effectiveness of the flu vaccine over 96 flu seasons.
For elderly people living in the community, inactivated influenza vaccines prevented up to 30 percent of hospitalizations for pneumonia but were not effective against the flu, flu-like illnesses or pneumonia. "The vaccines didn't seem to prevent influenza," Jefferson said.
For elderly people living in long-term care facilities, the picture was slightly brighter, with vaccines preventing up to 42 percent of deaths caused by influenza and pneumonia only.
"We have to concentrate our resources elsewhere or invest in better vaccines," Jefferson stated.
The authors of the second study screened 7,000 influenza A isolates for gene mutations known to confer drug resistance to the antivirals amantadine and rimantadine.
Overall drug resistance increased from 0.4 percent in 1994-95 to 12.3 percent in 2003-04. Also, 61 percent of resistant viruses isolated since 2003 were from people in Asia. Some Asian countries had drug resistance frequencies exceeding 70 percent, possibly a reflection of different prescribing practices.
Strikingly, more than 84 percent of all resistant viruses during the 10-year period under question were identified since the 2003 flu season.
This highlights the importance of continuing to expand surveillance of the emergence of resistance to these drugs, said Rick Bright, lead author of the study and a research scientist with the CDC.
"This is a warning that overuse of antiviral drugs leads to resistance," Siegel said. "The drugs should be specifically used for influenza that is a problem in terms of duration and possible risk of death, not for everybody."
The study authors voiced concern that rising rates of resistance will render amantadine and rimantadine ineffective for treatment or prevention in the event of an influenza pandemic. That, in turn, would render government stockpiles useless.
"I question stockpiling these drugs. You're going to have to discard or overuse them. It's sending a message to the public that these are lifesaving drugs," Siegel said. "Antivirals should be considered in high-risk cases," but in other cases they may only be of limited effectiveness, he said.
"We have to differentiate between potential risk and something that clearly is in the offing. Fear is a warning system that is supposed to protect us against imminent danger such as a gorilla hanging over us," he added. "I want to know why more effort isn't put on getting our vaccination method up-to-date instead of stockpiling millions of doses of vaccine and sending a fear message. We need to see reality."
More information
The National Institute of Allergy and Infectious Diseases has a fact sheet on the flu.
Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
FDA Gives Conditional Approval to 2nd Silicone Breast Implant
The U.S. Food and Drug Administration said Wednesday that it has granted a second manufacturer of silicone gel-filled breast implants a "conditional approval," taking the company a step closer to returning the controversial implants to the market, the Associated Press reported.
The FDA told Inamed Corp., of Santa Barbara, Calif., that its implants can be approved under certain conditions, but the agency did not spell out those conditions.
In July, the agency gave a similar, conditional approval to manufacturer Mentor Corp., also of Santa Barbara, after an FDA advisory panel voted to recommend approval of the company's application to sell the implants, the AP said.
But the panel at the time recommended against Inamed's implants, citing safety concerns. The FDA said Wednesday that Inamed has subsequently provided additional information to address those concerns.
Silicone gel implants went on sale in 1962 in the United States. Thirty years later, the FDA banned all but those used for breast cancer reconstruction, amid fears that leaks might be responsible for autoimmune diseases and even cancer. Other problems included the fact that many women needed repeat operations to deal with painful scar tissue.
By 1998, more than 170,000 lawsuits had been filed against implant manufacturers by women claiming their silicone implants had caused immune system disorders and chronic diseases such as rheumatoid arthritis and systemic lupus. Four companies paid out millions of dollars in settlements to the women, and one of them, Dow Corning, filed for bankruptcy to pay $3.2 billion to settle its claims.
However, studies by the Mayo Clinic, Harvard Medical School and the Institute of Medicine (IOM) panel from the National Academy of Sciences subsequently found no evidence that leaked silicone from gel implants caused systemic disease.
Proponents of silicone implants say they look and feel more natural than saline implants.
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FDA Rejects Liquid Cox-2 Painkiller
Pfizer Inc.'s application for an injectable liquid form of a cox-2 painkiller was rejected by the U.S. Food and Drug Administration, the Associated Press reported.
The FDA issued a "non-approvable" letter for the drug parecoxib sodium, which is marketed as Dynastat in the European Union and other parts of the world. The reasons behind the refusal were not disclosed, the AP reported.
Pfizer said it plans to meet with the FDA to discuss the rejection of the drug. The company contends that Dynastat, the only injectable cox-2 inhibitor, reduces the need to use opioids to control post-surgical pain.
Cox-2 inhibitors have been linked to increased risk of heart problems. Vioxx and Bextra have been removed from the market, and Celebrex now contains a warning label.
This is the second recent FDA rejection of a Pfizer application. Less than a week ago, the agency denied a Pfizer application for an osteoporosis drug, the AP reported.
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Personalized Drug Treatment Still Years Away: Report
Despite much hype, individually tailored drug treatments based on a person's genes are still at least 15 to 20 years away, says a report by the Royal Society in Great Britain.
"Personalized medicines show promise but they have undoubtedly been over-hyped. With the human genome sequenced, some people are expecting personalized medicines within a few years, but the reality is still many years away," noted Royal Society working group chairman Sir David Weatherall.
"There are some examples around today, but the complex multiple causes of diseases mean it will be at least 15 to 20 years before a patient's genetic make-up is a major factor in determining which drugs they are prescribed," he said.
The report said more funding and research are required to further the development of individually tailored drugs, BBC News reported.
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Asian Countries Agree on Plan to Fight Emerging Diseases
A strategy to counter bird flu and other emerging diseases has been approved by a group of 37 Asian countries at a regional meeting of the World Health Organization (WHO), Agence France-Presse reported.
The strategy has five key objectives to be subject to annual monitoring. These include: reducing the risk of emerging diseases; strengthening early detection of outbreaks; better early response to emerging diseases; improved preparedness for emerging diseases; and a sustainable technical collaboration between Asian-Pacific countries.
"It is very heartening that the nations of Asia have made this commitment, the WHO is anxious to make sure it is followed through on the ground. What we really needed was a pan-Asian, country-by-country commitment and that is what we got today," WHO spokesman Peter Cordingley told AFP
However, another WHO official said the strategy would not work without the support of wealthier nations. It will cost about $160 million to implement the strategy.
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HIV Drug Trial Halted Due to Liver Worries
Tests of a new HIV drug called aplaviroc have been halted after two patients suffered serious liver damage, GlaxoSmithKline announced Tuesday.
The compound is one of a new generation of drugs called CCR5 antagonists, which are being developed in order to treat HIV patients who've developed resistance to protease inhibitors like AZT, the Philadelphia Inquirer reported.
GlaxoSmithKline said it has stopped treatment of all 300 HIV patients taking part in the phase II clinical trial of aplaviroc. This trial was being conducted on patients in the United States, Canada and Europe who've never received HIV drugs. The two patients who suffered liver damage did not die and were not given liver transplants.
"We don't know whether (the problems) were drug-related, but in the interest of safety we have notified the investigators to take all the patients off aplaviroc," GlaxoSmithKline spokesperson Rick Koenig told the Inquirer.
Although it halted this trial, GlaxoSmithKline is still testing aplaviroc in a phase III trial involving 40 patients who have previously received other HIV drugs.
Two other drug makers -- Pfizer Inc. and Schering-Plough Corp. -- are also developing CCR5 antagonist drugs and have not reported any liver damage problems, the Inquirer reported.
