How effective is the new varicella zoster virus vaccine and when should adults receive it?
Who should recieve the new Tdap vaccine?
The answers to these and other immunization-related questions are addressed by the Centers for Disease Control and Prevention (CDC) in a number of recently-issued immunization recommendations. Here, by vaccine, is a quick review of these recommendations. (Several were reviewed in a previous Practice Alert. March 2007 issue of JFPRotavirus vaccine is 74% effective in preventing all rotavirus gastroenteritis and 98% effective in preventing severe rotavirus gastroenteritis.4 It is contraindicated in those who have had a severe allergic reaction to the vaccine and should be used with caution in children with altered immunocompetence, acute gastroenteritis, and moderate-to-severe illness. Even though it’s a modified live virus, it can be used in infants even if someone in the household is pregnant or immune-deficient.
Human papilloma virus
The quadrivalent human papilloma virus (HPV) vaccine was licensed by the US Food and Drug Administration (FDA) in June 2006; the CDC released its recommendations for its use in March 2007.5 The vaccine should be administered routinely to all girls aged 11 to 12 and can be started as early as age 9. The vaccine should also be given to women ages 13 to 26 who have not previously received the vaccine.
HPV is responsible for over 6 million new infections per year, although only a small proportion of these infections involve types that pose high risk for cervical cancer.5,6 The virus is associated with cervical cancer, genital warts, anal cancer, and possibly oral and pharyngeal cancer. TABLE 3 shows the number of each type of cancer that occurs in the US each year and the proportion attributed to HPV. There are over 11,000 new cases of cervical cancer and 3700 deaths from the disease each year.7,8
The HPV vaccine is produced in yeast using recombinant DNA technology and contains virus-like products of 4 HPV subtypes (6, 11, 16, and 18) that are responsible for between 60% and 80% of cervical cancers in the US. It prevents persistent HPV infection, genital warts, and cervical, vaginal and vulvar precancerous lesions due to the 4 subtypes contained. Since the vaccine does not completely protect from cervical cancer, Pap smear testing is still recommended after vaccination.
The vaccine is administered intramuscularly in 3 doses at months 0, 2, and 6. The minimum interval between doses 1 and 2 is 4 weeks and between doses 2 and 3, 12 weeks. It is contraindicated in those with allergies to yeast and other vaccine components. It can be coadministered with other vaccines but should be deferred for moderate to severe illness. The most common side effects are pain, swelling, and redness at the injection site; fever occurs at a rate slightly above placebo. The vaccine has not been tested for safety for use in pregnancy, but inadvertent administration during pregnancy has not led to any documented adverse effects.
TABLE 3
Cancers associated with HPV—US, 2003
| CANCER | CASES | % ATTRIBUTABLE TO ONCOGENIC HPV |
|---|---|---|
| Cervix* | 11,820 | 100 |
| Anus† | 4187 | 90 |
| Vulva† | 3507 | 40 |
| Vagina† | 1070 | 40 |
| Penis† | 1059 | 40 |
| Oral cavity/pharynx† | 29,627 | ≤12 |
| *A total of 70% of these cancers are attributable to HPV types 16 or 18. | ||
| †Majority of these cancers are attributable to HPV type 16. | ||
| Sources: US Cancer Statistics Working Group. United States Cancer Statistics: 2003. Incidence and Mortality. Altanta, Ga: US Department of Health and Human Services, CDC, and the National Cancer Institute; 2006; Parkin M. The global health burden of infection-associated cancers in the year 2002. Int J Cancer 2006; 118:3030–3044. | ||
Correspondence
Doug Campos-Outcalt, MD, MPA, 55 E. Van Buren, Phoenix, AZ 85004. dougco@u.arizona.edu