Monday, January 17, 2011

Compiled Research on Prevnar

Continuing the vaccine series, here is the information I have saved on the Prevnar vaccine, which is supposed to provide protection against the bacteria Streptococcus Pneumoniae.

This bacteria is typically present on the nares of healthy people. (Meaning, it colonizes on our bodies). In unhealthy people, it can result in pneumonia and otitis media. Similar to the way you get an overgrowth of yeast and then a yeast infection because you are not healthy, streptococcus becomes invasive when you are run down or your body is out of balance. Those with chronic health conditions, autoimmune disorders, transplant patients, etc are also at increased risk of complications.

Here is the product insert for the original vaccine, Prevnar7, which was used into 2010:

Here is the product insert for the new vaccine, Prevnar13:

Prevnar contains aluminum as an adjuvant. Check out this discussion to learn how aluminum works:

The primary concern with bacterial vaccines (Prevnar, Menactra, Hib etc) is Serotype Replacement. (SR) Here is a one-stop shop for a compilation of peer-reviewed studies on Serotype Replacement:

This article shows that SR concerns were identified in 1992 but basically ignored:

News articles:

Following the deaths of three babies within a two-week period, authorities in Holland have banned a batch of Prevenar, also known as Prevnar, reported Reuters. The babies all died within two weeks of receiving the vaccination.

A vaccine that has dramatically curbed pneumonia and other serious illnesses in children is having an unfortunate effect: promoting new superbugs that cause ear infections.”

Cases of a life-threatening form of pneumonia that affects the young are rising rapidly in Britain. It now affects around 1,000 children a year. The cause of the increase is unknown but experts fear a vaccine in the immunisation programme could be contributing.”

Medical literature:

Vaccine complications:

The increase in bacterial colonization of the nasopharynx during AOM could be associated with an increase in AOM pathogens and theoretically can predispose PCV7-immunized children with AOM to a higher rate of antibiotic treatment failure or recurrent AOM.” 

These findings suggest a natural competition between colonisation with vaccine-type pneumococci and S aureus, which might explain the increase in S aureus-related otitis media after vaccination.”

”In the years following introduction of PCV7, a strain of S pneumoniae has emerged in the United States as an otopathogen that is resistant to all FDA-approved antibiotics for treatment of AOM in children.” 

”The number of episodes attributed to serotypes that are cross-reactive with those in the vaccine was reduced by 51 percent, whereas the number of episodes due to all other serotypes increased by 33 percent.” 

Five-fold increase in pediatric parapneumonic empyema since introduction of pneumococcal conjugate vaccine:

Incidence of pneumonia is not reduced by pneumococcal conjugate vaccine: 

”The proportion of Gram-negative bacteria became 2-fold more frequent than S. pneumoniae in AOM in PCV7-vaccinated young children where PCV7 uptake was community-wide and supply was adequate.”

“However, immunization can also place selective pressure on the nasopharyngeal flora, promoting the emergence of new pathogens. A shift towards non-vaccineserotypes has been observed among vaccinees in several studies. 109 In South Africa, the carriage of non-vaccine serotypes was increased from 24% in controls to 36% in the vaccines group. A significant increase was seen in the carriage of serotypes 7 and 15, important causes of invasive disease.109”

“FINDINGS: We noted no reduction of AOM episodes in the pneumococcal vaccine group compared with controls (intention-to-treat analysis: rate ratio 1.25, 95% CI 0.99-1.57). Although nasopharyngeal carriage of pneumococci of serotypes included in the conjugate-vaccine was greatly reduced after pneumococcal vaccinations, immediate and complete replacement by non-vaccine pneumococcal serotypes took place.”

“The bactericidal activity of Streptococcus pneumoniae toward Staphylococcus aureus is mediated by hydrogen peroxide. Catalase eliminated this activity. Pneumococci grown anaerobically or genetically lacking pyruvate oxidase (SpxB) were not bactericidal, nor were nonpneumococcal streptococci. These results provide a possible mechanistic explanation for the interspecies interference observed in epidemiologic studies.”

”Among 790 children screened, 43% carried S pneumoniae and 10% carried S aureus. Staphylococcus aureus carriage among S pneumoniae carriers was 6.5% vs 12.9% in S pneumoniae noncarriers. Streptococcus pneumoniae carriage among S aureus carriers was 27.5% vs 44.8% in S aureus noncarriers. Only 2.8% carried both pathogens concomitantly vs 4.3% expected dual carriage (P = .03). Risk factors for S pneumoniae carriage (attending day care, having young siblings, and age older than 3 months) were negatively associated with S aureus carriage. 

Streptococcus pneumoniae carriage, specifically of vaccine-type strains, is negatively associated with S aureus carriage in children. The implications of these findings in the pneumococcal vaccine era require further investigation.”

Whether the current increase in severe community-acquired S. aureus infections, including methicillin-resistant S. aureus (6), is partially caused by the recent introduction of the pneumococcal conjugate vaccine is yet to be determined.”

More recent studies have shown increases in the proportion of Haemophilus influenzae and Moraxella catarrhalis in the middle-ear fluid of PCV7-immunized children. There has been no report on the effect of PCV7 on all 3 bacterial pathogens combined, either in the middle-ear fluid or nasopharynx of individual children with AOM. We investigated the impact of PCV7 on nasopharyngeal colonization with bacterial pathogens during AOM in the pre-PCV7 and post-PCV7 vaccination eras. Four hundred seventeen children (6 months to 4 years of age) were enrolled onto AOM studies between September 1995 and December 2004. Of these, 200 were enrolled before the vaccine use (historical controls), and 217 were enrolled after the initiation of PCV7 vaccination (101 were underimmunized, and 116 were immunized). Although the nasopharyngeal colonization rate for S pneumoniae was not different between the 3 groups, a significantly higher proportion of PCV7-immunized children with AOM were colonized with M catarrhalis. Overall, the mean number of pathogenic bacteria types isolated from immunized children (1.7) was significantly higher than in controls (1.4). The increase in bacterial colonization of the nasopharynx during AOM could be associated with an increase in AOM pathogens and theoretically can predispose PCV7-immunized children with AOM to a higher rate of antibiotic treatment failure or recurrent AOM.”

 “The rates of invasive pneumococcal disease (IPD), serotype distribution and antimicrobial susceptibility prior to and after the introduction of the heptavalent pneumococcal conjugate vaccine in Portuguese children were evaluated. The changes in incidence of IPD in children under 1 year old between the two periods of the study was not significant (P=0.53), despite the 21% decline. In children under 18 years old there was a 27.7% decrease in vaccine serotypes. All nonvaccine serotypes increased 71.4%. The decrease in vaccine serotypes was more impressive during the first year of life (−54.8%) than for children between 1 and 5 years of age (−19.1%). Among children under 1 year old, penicillin nonsusceptible isolates declined between the two periods of the study (47.2% vs. 25.0%) (P=0.03), as did those of cefotaxime and ceftriaxone nonsusceptible isolates. No changes were observed for isolates nonsusceptible to tetracycline and macrolides. The serotypes of these nonsusceptible isolates differed after the introduction of vaccine (P=0.01). Multiresistance increased 57.1% after the introduction of vaccine. Multiresistant isolates with vaccine serotype declined 42.9% (P<0.001), and nonvaccine serotypes appeared during the vaccination period (P<0.001). These findings suggest a replacement of vaccine serotypes by nonvaccine serotypes, mainly among nonsusceptible isolates.”

"In France, despite a high rate of pneumococcal conjugate vaccine coverage, the number of cases of pneumococcal meningitis in children did not decline significantly between 2001–2002 (n = 264) and 2007–2008"

The vaccine is not effective for post-exposure concerns, either:

“Immunization with Prevnar after the known exposure has occurred is also not effective in preventing disease, since there is insufficient time for protective antibodies to develop to protect the vaccinated person”

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