Although HBV has numerous antigens, only the presence of HBsAg indicates active infection. Antibody to HBsAg, from either disease or vaccine, indicates immunity.
This graphic shows the distribution of risk factors in 2001. Persons with multiple sexual contacts, men who have sex with men, and sexual contact with a person known to have HBV infection account for 54 percent of cases with a known risk factor. Injection drug use accounts for 20 percent of cases. About 3 percent of cases are in people who have household contact with a person with acute or chronic hepatitis B. Fifteen years ago, health care workers accounted for 2 percent of HBV infections- 2 or 3 thousand new infections each year. Since that time, the rate of infection among health care workers has declined by 95 percent, and is now lower than the rate for the general population. Hepatitis B vaccine has made occupational HBV infection a thing of the past.
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In December 2002, the US Food and Drug Administration approved a new combination vaccine- Pediarix- which is manufactured by Glaxo Smith Kline. This vaccine contains DTaP, inactivated polio and hepatitis B vaccines. The DTaP component is Infanrix, and the hepatitis B component is Engerix-B, which were previously licensed in the U.S. Pediarix is approved for the first three doses of the DTAP and IPV series, which are usually given at about 2, 4, and 6 months of age. However, Pediarix is approved for use through 6 years of age. The minimum age for the first dose of Pediarix is 6 weeks. So it can’t be used for the birth dose of the hepatitis B series.
Interchangeable Can be used after a birth dose of heaptitis B – total of 4 doses O.K. Pediarix may be used in infants born to women who are hepatitis B surface antigen positive or whose hepatitis B status is unknown. Like COMVAX, Pediarix is not approved for this use. But at it’s February 2003 meeting, ACIP voted to allow the use of Pediarix to complete the hepatitis B series in these infants. But remember that the minimum age for Pediarix is 6 weeks, so it must NOT be used for the birth or one month dose of the hepatitis B series. Another important fact to remember about Pediarix is that the minimum intervals between doses are dictated by the single antigen with the longest minimum intervals. Therefore, Pediarix minimum intervals are determined by the hepatitis B component. As for hepatitis B vaccine, the minimum interval between the first two doses of Pediarix is 4 weeks. The third dose must be administered at least 8 weeks after the second dose, and should follow the first dose by at least 16 weeks. The third dose should not be given before 6 months of age to be counted as a valid third dose of hepatitis B vaccine.
Recombivax HB (Merck) - 5.0 mcg/0.5 mL (pediatric) - 10 mcg/1 mL (adult) - 40 mcg/1 mL (dialysis)
Engerix-B (GSK) - 10 mcg/0.5 mL (pediatric) - 20 mcg/1 mL (adult)
Protection* by Age Group and Dose * Anti-HBs antibody titer of 10 mIU/mL or higher ** Preterm infants less than 2 kg have been shown to respond to vaccination less often *** Factors that may lower vaccine response rates are age >40 years, male gender, smoking, obesity, and immune deficiency 90%-95% 98%-100% 3 75%-80% 80%-95% 2 20%-30% 16%-40% 1 Teens and Adults*** Infants** Dose
HIV/AIDS, TB and malaria kill 6 million people every year; nearly 2 million deaths are caused by TB
2 billion people — one third of the world's population — are infected with TB bacilli, the microbes that cause TB. 1 in 10 people infected with TB bacilli will become sick with active TB in their lifetime; people with HIV are at a much greater risk
Almost 9 million new TB cases occurred in 2004 — 80% of them in 22 countries
Bacillus of Calmette and Guérin (BCG) is a vaccine against tuberculosis that is prepared from a strain of the attenuated (weakened) live bovine tuberculosis bacillus, Mycobacterium bovis, that has lost its virulence in humans by being specially cultured in an artificial medium for years. The bacilli have retained enough strong antigenicity to become a somewhat effective vaccine for the prevention of human tuberculosis. At best, the BCG vaccine is 80% effective in preventing tuberculosis for a duration of 15 years.
*Although skin testing programs should be conducted only among high-risk groups, certain individuals may require TST for employment or school attendance. Diagnosis and treatment of LTBI should always be tied to risk assessment. 15-mm induration is interpreted as positive in ____________________________________________________
Factors That May Cause False-Positive TST Reactions
Reactions caused by nontuberculous mycobacteria are usually 10 mm of induration
Reactivity in BCG vaccine recipients generally wanes over time; positive TST result is likely due to TB infection if risk factors are present
Factors That May Cause False-Negative TST Reactions (1)
Inability to react to a TST because of a weakened immune system
Usefulness of anergy testing in TST-negative persons who are HIV infected has not been demonstrated
Factors That May Cause False-Negative TST Reactions (2)
Recent TB infection
Defined as 2 to 10 weeks after exposure
Very young age
Factors That May Cause False-Negative TST Reactions (3)
For example, measles or smallpox
Can temporarily suppress TST reactivity
Overwhelming TB disease
Poor TST administration technique
For example, TST injection too shallow or too deep, or wheal is too small
Convulsions with or without fever occurring within 3 days
*may consider use in outbreaks
Pertussis Vaccine Use in Children with Underlying Neurologic Disorders Underlying Condition Prior seizure Suspected neurologic disorder Neurologic event between doses Stable/resolved neurologic condition Recommendation Delay and assess* Delay and assess* Delay and assess* Vaccinate * vaccinate after treatment initiated and condition stabilized
Tetanus Wound Management * Yes, if >10 years since last dose ** Yes, if >5 years since last dose Vaccination History Unknown or <3 doses 3+ doses Td TIG Yes No No* No Td TIG Yes Yes No** No Clean, minor wounds All other wounds