Novel smallpox vaccine should be safe for eczema patients

The US government has ordered 20 million doses of a vaccine that should protect eczema patients from smallpox without exposing them to the risk of developing eczema vaccinatum, a life-threatening infection, according to a press release by the vaccine’s manufacturer, the Danish biotechnology company Bavarian Nordic.

This means that, in the event of a smallpox bioterror attack, instead of relying on the dubious security of herd immunity, people like you and me can get vaccinated. Until the advent of this new vaccine, we could not.

Eczema vaccinatum made the headlines in 2007 when an Iraq-bound US soldier received a live smallpox vaccine and transmitted the vaccinia virus to his two-year-old son, who nearly died. The son suffered from eczema, which the father had had as a child.

According to a story in Science magazine,

The current smallpox vaccine is an old formulation made with live vaccinia virus, a relatively benign cousin of the variola virus that causes smallpox. Serious side effects in immunocompromised patients and children are rare but well-known; former chancellor of the University of Colorado Health Sciences Center Vincent Fulginiti, 75, an expert on these adverse events, saw eczema vaccinatum cases often in the 1960s through 1972, when children were routinely immunized for smallpox.

After wild smallpox was declared eradicated in 1979, vaccinations continued only for members of the U.S. military. They had to be protected, the government decided, because they might be the first to encounter the lethal virus if secret stocks were deployed by an enemy. That program ended in 1990. In 2002, however, in the wake of the post-9/11 anthrax attacks, the Bush Administration resumed vaccinations for soldiers, but included screening so that people at risk for side effects would be excluded.

The Centers for Disease Control and Prevention currently recommend that

If smallpox is not an immediate risk, vaccination should not be performed in persons with eczema or atopic dermatitis or in persons with household or close physical contacts with these conditions.

The new vaccine, “IMVAMUNE®,” is based on a strain of vaccinia virus developed by Bavarian Nordic. IMVAMUNE®, while live, has been “attenuated,”  which I take to mean genetically altered, so that it cannot make copies of itself. After developing antibodies against the virus, the immune system clears it from the body.

Bavarian Nordic says it will deliver the 20 million doses to the US by [the end of?] 2013.

The US military has long disqualified potential recruits from service if they had eczema after the age of nine. I wonder whether this vaccine will change anything. If so, probably not for a long time!