Why do some individuals have more infections than others?

Nasopharyngeal pneumococcal carriage after combined pneumococcal conjugate and polysaccharide vaccination in children with a history of recurrent acute otitis media

BACKGROUND

We recently showed that vaccination with a 7-valent pneumococcal conjugate vaccine (PCV7) followed by a 23-valent pneumococcal polysaccharide vaccine (PPSV23) failed to prevent new episodes of acute otitis media (AOM) in previously unvaccinated toddlers and children with a history of recurrent AOM. We describe in detail the impact of pneumococcal vaccinations on nasopharyngeal carriage of S. pneumoniae in this study population.

METHODS

The impact of vaccination with PCV7 followed by PPSV23 on pneumococcal nasopharyngeal carriage was studied in a prospective, randomized trial involving 383 children (age range, 1-7 years) with previous AOM. Nasopharyngeal swab specimens were collected at the time of first vaccination and at 6-7-month intervals during the 26-month follow-up period.

RESULTS

Overall, pneumococcal carriage rates did not diminish, remaining at approximately 50% in both PCV7/PPSV23 and control vaccinees. A significant shift from conjugate vaccine- to nonconjugate vaccine-type pneumococci was observed in children aged 1-2 years, who received the conjugate vaccine twice before the polysaccharide vaccine was administered. Conjugate vaccine serotype carriage was not influenced in older children, who received the conjugate vaccine once before receiving the polysaccharide booster.

CONCLUSIONS

The administration of conjugate vaccines at least twice also after 2 years of age may be mandatory for reducing the carriage of conjugate vaccine serotypes in children with recurrent AOM. Polysaccharide booster vaccination did not affect nasopharyngeal colonization with serotypes not included in the conjugate vaccine.

How the mind hurts and heals the body

The author reviews some of the social and behavioral factors acting on the brain that influence health, illness, and death. Supported with data from several areas of research, his proposal for understanding health and illness provides both the concepts and the mechanisms for studying and explaining mind-body relationships. The brain is the body's first line of defense against illness, and the mind is the emergent functioning of the brain. This mind-body approach incorporates ideas, belief systems, and hopes as well as biochemistry, physiology, and anatomy. Changing thoughts imply a changing brain and thus a changing biology and body. Belief systems provide a baseline for the functioning brain upon which other variables act and have their effects.

Genetic predisposition to infectious pathogens: a review of less familiar variants

The susceptibility and clinical manifestations of infectious diseases in human populations are influenced by a variety of factors, among them host genetics. Obvious examples for the effect of host genetics on predisposition to unique infections are the primary immunodeficiency diseases. Minor gene variants that influence the host immune system are much more common. The iceberg model can be used to illustrate the epidemiology of immunodeficiency states. Accordingly only a few individuals have known and severe recognized primary immunodeficiencies, whereas many more patients have mild immunodeficiencies that may remain undiagnosed and are predisposed to a unique infectious disease. We review some of the less common variants that influence the host defense and predispose to certain infectious agents or change their outcome.

Stroke prevention therapy beyond antithrombotics: unifying mechanisms in ischemic stroke pathogenesis and implications for therapy: an invited review

BACKGROUND

It is estimated that about half of cardiovascular disease risk is explained by conventional risk factors. The realization that atherosclerosis is an inflammatory disease has led to a search for new stroke and cardiovascular disease risk factors and treatments. As such, the vulnerable atherosclerotic plaque has become the main focus for new medical strategies for plaque stabilization and stroke prevention.

SUMMARY OF REVIEW

In this invited review, I discuss inflammation as a possible risk factor for stroke, unifying mechanisms in ischemic stroke pathogenesis, and new avenues for stroke prevention---statin agents, angiotensin-converting enzyme inhibitors, and vitamins. These new stroke prevention therapies may help to reduce inflammation, serve to stabilize the atherosclerotic plaque, or act by other protective mechanisms.

CONCLUSION

Beyond the traditional antithrombotic agents, statin agents, angiotensin-converting enzyme inhibitors, and vitamins may prove to be important additions to our armamentarium for stroke prevention.