The U.S. Centers for Disease Control and Prevention (CDC) has reported low rates of influenza vaccination among the elderly, high-risk groups, and pregnant women.

An analysis of data from a 2003 review of the US public health system showed that vaccination is not given to all potentially elderly people (65.6% vs 90% of the population target of people over 65), as well as adults with one or more risk factors for complications of the infection (34.1% vs 60% of the target population). Ethnic and racial differences were observed in the two population groups. Thus, the vaccination rate of Africans and Hispanics was lower than that of people with white skin (48% and 45.4% vs 68.7% for the elderly; 30.4% and 27% vs 35.8% for patients at risk). Analysis of temporal trends showed a slight increase in the frequency of vaccination in white-skinned people and elderly African-Americans, as well as in young people belonging to high-risk groups, and a decrease in its frequency in Hispanic elderly. The lack of immunization was helped by the poor financial situation, the low level of education, the inaccessibility of medical care and vaccines.

In 1997-2003 The United States Advisory Committee on Immunization included healthy pregnant women who are in the third to third trimesters of pregnancy during the seasonal incidence of influenza, as well as women of all ages. gestational age with a number of chronic diseases such as bronchial asthma, diabetes mellitus and pathology of the cardiovascular system, to a group of people at increased risk of infection who have been found to be vaccinated. However, despite these recommendations, only 13% of pregnant women in the United States received the flu vaccine in 2003.

A survey by the American College of Obstetrics and Gynecologists with the support of the CDC in 2004 showed that 52% of obstetrician-gynecologists support the use of the flu vaccine in healthy women during the first trimester of pregnancy , 95% after the first trimester and 63% recommend medical vaccination in the first trimester. However, 36 to 38% of physicians who recommend vaccination do not administer it in their own clinical practice.

According to the CDC, the data underscored the need for broader and more effective measures to increase vaccination rates, particularly among national minorities and pregnant women.