Public health officials face difficult choices in deciding who should get scarce doses of flu vaccine. Their job could be made easier with guidance from the federal Centers for Disease Control and Prevention, as suggested by Maine’s senators. They have asked the CDC and Department of Health and Human Services to serve as a clearinghouse of vaccines and information, rather than leaving decisions up to individual states. In addition, they have asked the department to look at individual state needs rather than simply sending each state half its requested supply of shots.

Last month, British regulators announced they were shutting down a Liverpool factory owned by Chiron Corp. The factory was supposed to send 48 doses of flu vaccine to the United States for use this fall and winter. The remainder of the U.S. supply comes from Aventis Pasteur in France, which has begun shipping 54 million doses. The number of available flu shots has been cut almost in half. An estimated 180 million people are considered at high risk for complications from the flu. But typically no more than 87 million Americans seek out the immunizations.

The Maine Bureau of Health ordered 150,000 doses of flu vaccine to be distributed to low-income, high-risk residents. The majority of those doses – 123,000 – were to come from Chiron because the CDC assigned Maine’s order to the company. The remaining doses are from Aventis. Private medical practices ordered their own doses from the two companies.

The HHS department has suggested that it will work with states to ensure that they get half the number of shots they ordered. Parceling out the vaccine in this way, although it might seem fair, does not make sense from a health perspective. Maine, for example, ranks seventh in the country for the percentage of residents over 65, people who are considered “high risk” for getting the flu. The state also has a high percentage of residents with chronic health problems, another high-risk group. On the other hand, it had the lowest percentage of population under the age of 5, according to the 2000 census.

The senators envision the CDC as a clearinghouse where health care providers could report their needs for vaccines. This information is now supposed to be reported to county health departments, which don’t exist everywhere. Further, many local departments can only request shots within the same states. Having the CDC oversee the process would broaden the scope while ensuring that doses get to those who need them most.

Sen. Susan Collins has also requested more information on the effectiveness of using partial doses to maximize the vaccine supply. She points to clinical studies that have shown that using as little as 1/10th of the usual dose is still effective.

Beyond these issues, the CDC is preparing to deal with questions about allocating the vaccine within the high-risk population. Last week, for the first time, the agency created a permanent panel of ethicists on vaccine distribution. The group, which has already met once, will be confronted with decisions such as whether to vaccinate babies, who are more susceptible to the flu, or the elderly, who are more likely to die from it.

These are tough decisions, but ones that likely will have to be made as more people want shots than will actually get them.