Last Updated

05 Dec 2002

Source: Baltimore Sun, December 19, 2001.

OPINION/EDITORIAL

Smallpox vaccine poses great danger

By Fred Rosen

BOSTON - In light of our recent experience with anthrax, should we vaccinate all Americans against the more deadly bio-weapon, smallpox?

Despite efforts to fit ourselves with new layers of protection - National Guard units in airports, stockpiles of Cipro, irradiated mail - a sense of heightened risk remains in the air. The remedies themselves are alarming, and so we reach for the comforting absolute of vaccination, as evidenced by the federal government's move to contract out the production of more than 200 million doses of smallpox vaccine.

There has always been a degree of morbidity associated with the smallpox vaccine, but in the past the threat of the devastating disease far outweighed the risks. Today, however, the risks of mass vaccination appear to outweigh the supposed threat.

Simply put, if we push forward a widespread program of smallpox vaccination, we will kill thousands of individuals infected with HIV, as well as many children suffering from primary immunodeficiency diseases. Also at risk are people with compromised immune systems such as the elderly, patients on steroids (a common treatment for children with asthma), and those receiving chemotherapy. We may be looking at 20 million people who will face adverse reactions to the smallpox vaccine.

AIDS, of course, had not appeared in the 1970s, the last time that schoolchildren were required to receive the smallpox vaccine. Nor did we have a new generation of anti-viral drugs; some of these drugs may effectively treat smallpox. So we are facing a new public health landscape, with new variables that must be carefully considered. Requiring HIV tests prior to vaccination would be a costly and controversial measure. Also, there's another risk. For those who remember receiving the smallpox vaccine, the shot produces a scab at the point of injection. This scab takes several days to fall off and is highly infectious. Contact with the scab - either before or after it falls off - could produce adverse or fatal reactions for anyone with an impaired immune system.

The public craves maximum immunity from threats both actual and perceived. We reach for the technological fix, the biomedical magic bullet. But it makes no sense to take extreme action out of fear or simply because we have the resources to do so. We must avoid traveling down a path of hysteria.

There are effective intermediate steps we can take.

Creating a national laboratory to speed the production of vaccines is a good idea. Producing a reasonable stockpile of smallpox vaccine, in case of a bio-terrorist attack, is also prudent. We must also strengthen support for basic research on regulation of the immune system. This will enhance our ability to develop safe vaccines that protect against potential bio-weapons as well as current epidemics such as AIDS, tuberculosis and malaria.

Smallpox, actually, was believed to be eradicated from the planet in 1977, roughly 200 years after an English doctor named Edward Jenner conducted the first scientific demonstration that vaccination works. His smallpox vaccine was an epochal discovery - for its science that launched modern immunology and for the innumerable lives it has saved (300,000 children died of smallpox in Sweden alone during the second half of the 18th century).

Thomas Jefferson, in a letter to Jenner, wrote that "future generations will know by history only that the loathsome smallpox existed and by you has been extirpated."

Future generations will also judge the wisdom of our actions as we react to the terrorist attacks against our country. We will not be judged well if we seek protection against an imaginary threat at the expense of the frailest among us.

Fred Rosen is president of the Center for Blood Research in Boston, the James L. Gamble Professor of Pediatrics at Harvard Medical School and an authority on immunodeficiences.