Last Updated

20 Nov 2002

Source: USA Today, November 19, 2002.

EDITORIAL/OPINION

Don't offer all Americans smallpox vaccinations now

By Henry I. Miller and David Longtin for USA TODAY

The Bush administration soon will decide whether to offer smallpox inoculations to all Americans, even without a clear bioterrorist threat. If it does, it will be caving in to growing but largely uninformed public demands for widespread "pre-emptive" vaccinations after long resisting this reckless idea.

Most Americans say they would take the smallpox vaccine if it were offered, even after hearing that the disease was eradicated from nature decades ago and that the vaccine carries major risks. A nationwide survey in May by Harvard University and the Robert Wood Johnson Foundation found that 59% of the 2,000 people questioned would get vaccinated, despite the potential consequences.

The vaccine is not much improved from the one introduced in 1796. It consists of a live vaccinia virus, a close relative of smallpox, and has little in common with much safer modern vaccines. The smallpox vaccine can cause several severe side effects, including widespread infection of mucous membranes and the brain, and is expected to kill from one to three out of every million people who get it.

Further complications

Recent media analyses have warned of these hazards. Yet even those alarming reports have overlooked three crucial points:

The Centers for Disease Control and Prevention now recommends against giving the smallpox vaccine to anyone under age 18 unless an emergency already exists. Government scientists plan studies to determine whether newer versions of the vaccine are safe enough for children, which could take years. If the CDC's policy stands, it would undercut a mass pre-emptive vaccination effort.

Drug companies are developing poxvirus-based vaccines against HIV, as well as therapies to fight many cancers. But Joanna Shisler, a University of Illinois virologist who works with smallpox vaccines, warns that those who receive the smallpox vaccine will develop a long-term immunity that will interfere with these newer poxvirus-based treatments.

Widespread smallpox vaccinations may cause substantial shortages in the U.S. blood supply. Kay Gregory, regulatory affairs director of the American Association of Blood Banks, says federal authorities have yet to issue guidelines regarding how long blood banks must wait before accepting blood from donors who have received smallpox inoculations.

In the 1960s, when smallpox inoculations were common, health officials reported that 15 of every million vaccine recipients suffered life-threatening side effects. About 10 in a million developed encephalitis, an inflammation of the brain that can cause permanent neurological damage. Those with weakened immune systems or eczema were at higher risk.

Based on those old statistics, if 59% of all Americans were vaccinated now, hundreds would die, and many others would be disfigured or maimed. The toll could be higher because many scientists believe those old reports were too low and because the population is now older, with many more people with immune systems compromised by HIV infections, organ transplants, cancer chemotherapy or steroid treatment.

It is not surprising, then, that the panel of vaccine experts that advises the CDC recommended in June that the vaccine not be offered to the general population, particularly given the "low" probability of terrorists using smallpox.

Even if rogue nations have smallpox, they are unlikely to use it as a weapon in the USA. It would be a daunting task to put the virus into an aerosol that could infect large numbers of Americans before medical authorities could react.

If a smallpox attack did occur, health officials would know what to do. Control depends upon quarantine of infected individuals and focused, aggressive vaccination of all possible contacts.

It would be imprudent to inoculate everyone against a non-existent disease with a vaccine that has serious side effects. Better to immunize only a minimum of hospital workers and government first-responders who would investigate a reported outbreak, then vaccinate more widely if an actual case is found. Any other course of action would be driven more by public relations than public health.

Henry I. Miller, M.D., is a fellow at the Hoover Institution. David Longtin is a freelance writer.