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Vaccines for adult diseases

When the flu and pneumonia season arrives, shortly a surprising number of Americans will be caught with their antibodies down, (or no good reason. Around 48 million adults should consider being vaccinated against influenza or pneumonia, medical authorities say. Another 4 million ought to be vaccinated against hepatitis В, а sometimes fatal liver infection that is spreading at an alarming rate: there were 50 percent more new cases in 1986 than in 1981,

according to the Federal Centers for disease control. All told, Health officials estimate, infections for which vaccines already exist kill 70000 Americans a year and strike hundreds of thousands more — costing tens of billions of dollars in medical care and lost work.

It is curious that while Americans are more fussy about their health than ever before, they're neglecting the most powerful preventive measure in medicine. Shots have saved countless lives since childhood vaccines became widely used. There were 200000 U.S. cases of diphtheria reported in 1921 — none in 1986. Paralytic polio struck around 57000 in 1952 — only two last year. But even in light of such well-known medical triumphs, researchers say, no more than one in five adults whose life would be jeopardized by a vaccine-preventable infection gets immunized against it. "Historically, we've thought of immunization as something for children", says Dr. Alan Hinman, director of the CDC's division of immunization. "But it's an adult thing to do".

Are you unprotected? Whether you should prime your disease-fighting antibodies depends on your age and medical history and the probability of direct infection. For final advice, consult your doctor. So that you can take stock of your bodily defenses, here is a survey of the most threatening diseases for which vaccines are available.

Influenza: In a typical year, influenza kills 10000 to 40000 Americans. In the 1984/85 epidemic, a CDC official estimates, the toll was at least 50000. Influenza costs the nation $3 billion to $5 billion annually in productivity losses and health care, says Dr. David S. Fedson of the University of Virginia, head of the immunization task force of the American College of Physicians. In an epidemic year, he says, the expense is about S12 billion. The CDC now recommends the vaccine for persons over 65, for sufferers of chronic lung and heart disease and for adults living with such high-risk persons, ft is also advised for any adult who wants to lower the odds of getting the flu. The vaccine, which prevents infection in 60 to 70 per cent of recipients and lessens its severity in many others, is reformulated annually and should be taken every fall.

Doctors and patients shun flu shots today partly because of fears stemming from the swine-flu controversy of 1976, in which some 500 of the 45 million people given the vaccine mysteriously developed a neurological disease. Since that episode, says Leonard Kurland, a neurologist and epidemiologist at the Mayo Clinic, flu shots have caused no additional cases of Guillain-Barre syndrome. Today's highly purified flu vaccines, researchers say, "rarely" cause the feverish aches that plagued recipients of the first flu shots 30 years ago.

Pneumonia: Between 20000 and 40000 Americans die annually of pneumonia caused by pneumococcal bacteria. Like the flu shot, the pneumococcal vaccine is advised for the elderly and the chronically ill and those with whom they live.- The once-in-a-lifetime vaccine is the only preventive measure of any kind that Medicare covers.

A Veterans Administration study published in the "New England Journal of Medicine" last fall has caused some physicians to lose faith in the vaccine. The VA researchers studied 2295 men (mostly over 55) with chronic illness such as diabetes and alcoholism; the 1145 men who received vaccine, the researchers found, had no fewer cases of pneumococcal infection than men who didn't. But the oft-mentioned study is "invalid", some researchers say. For instance, Fedson says, too few subjects were tested for the vaccine's benefits to become apparent, and subjects who received vaccine were by chance more feeble than the controls. Neither the U.S. Public Health Service nor the CDC has changed its vaccine recommendations in the wake of the VA study. Experts still say it prevents infection in two out of three recipients who would otherwise become infected.

Hepatitis B: Following the do-as-l-say-and-not-as-l-do medical dictum, most physicians fail to immunize themselves against hepatitis B. Since the virus is transmitted via blood and blood products as well as semen and saliva, health-care workers are urged to get a vaccination: Yet, Hinman says, no more than 30 percent of physicians and 40 percent of dentists have done so. Others at high risk are gay men with multiple partners and i.v. drug abusers who share needles. The CDC also says that heterosexuals with more than one sex partner should consider the vaccine; of the 300000 or so people who became infected last year, says CDC epidemiologist Gary Schatz, about 120000 got it from heterosexual contact.

A major purpose of the vaccine is to stem the tide of virus carriers — now at 500000 to 1 million Americans and rising. About 10 percent of infected persons can't get rid of the hepatitis В virus and become chronic carriers; a fraction of them die of cirrhosis or liver cancer. But the vaccine, which is administered in three doses over six months and is thought to spur lifelong immunity, is not likely to become more popular until it's more convenient and much cheaper.

% Time to bring your immune system up to date? For those who received a tetanus or diphtheria vaccine, researchers recommend a booster every 10 years. And as many as 20 percent of Americans in their 20s and early 30s are susceptible to measles; either they didn't get the disease in childhood, and so have no natural immunity,

or they received a weak measles vaccine. As a result, measles outbreaks have lately occurred on college campuses, prompting some schools to require students t6 prove their immunity or roll up their sleeve. Another immunity gap is rubella, or German measles. About 15 percent of women of childbearing age are susceptible to rubella, which can cause birth defects.

While several once dreaded diseases are disappearing, influenza and pneumonia and hepatitis В are flourishing, relatively unchecked by vaccines. Fear of shots isn't the problem. Repeated surveys show that when physicians advise high-risk patients to get a vaccine, most of them follow doctor's orders.

THREE NEW VACCINES FOR JUNIOR

Two childhood illnesses — chicken pox and meningitis — may soon go the way of measles, diphtheria and polio as new vaccines reach the market in the next year or two. And a third new vaccine, against pertussis (whooping cough), could soon quell fears about adverse reactions associated with the current DPT (diphtheria, pertussis, tetanus) vaccine.

At the annual meeting of the American Academy of Pediatrics in New Orleans, pediatricians will be told that a chicken-pox vaccine at last has tested safe and effective and should be available in two years. The vaccine, against the varicella virus, would protect some 3,5 million young Americans who come down with chicken pox each year.

The illness usually hits between ages 5 and 10 — bringing fever, aches and a rash — and lasts a week. It also strikes adults, in whom the vaccine appears less effective in limited studies so far. A bigger problem: It is not known how long immunity lasts. The vaccine is still protecting kids in Japan after eight years of widespread use—a promising sign, says Dr. Alan Hinman, director of immunization programs at the Centers for Disease Control. If immunity wanes, periodic booster shots may solve the problem. "Parents will certainly be eager for this vaccine", Hinman predicts.

A new vaccine against hemophilus influenza type В — a bacterium that causes 12000 cases of meningitis and 7000 cases of other serious complications in infants each year — is also sure to ease parents' minds. A vaccine exists now that protects children aged 2 and older from the bacteria, but it is ineffective in younger kids, who account for 80 percent of cases. The new vaccine, being tested in Finland and Alaska, has proved effective in kids under 2. It's expected to be available by the end of 1988 — possibly sooner.

The new pertussis vaccine causes fewer minor adverse reactions, such as fever and swelling at the injection site,-than the current

DPT vaccine, studies show. More important: A version of the new vaccine, used in Japan since 1981 and being tested in Sweden and the U.S., appears to cause fewer cases of permanent brain damage and mental retardation. Brain damage occurs in 1 out of every 340000 children who get the current vaccine ~— about 50 per year in the United States. Untreated whooping cough produces 10 times as much brain damage as the vaccine. Mortality is highest among infants.

One defect in the Japanese data is that kids there get the vaccine at .age 2, and the risk of the disease is highest in the first year of life. U.S. officials now eagerly await the outcome of a Swedish study of 3000 6-month-old children who were given the newer vaccine a year ago.

Even if results look good, however, Japanese vaccine makers are fearful about applying for licensing in the United States. The reason: Liability. But Congress went a long way toward solving that problem for all vaccine makers when it authorized an excise tax on the DPT, measles, mumps and polio vaccines for a fund to cover the expenses of children who suffer serious side effects of vaccination.