Kevin Chatham-Stephens, MD, MPH, FAAP
CDR U.S. Public Health Service
MedicalResearch.com: What is the background for this study?
Response: Typhoid fever is a life-threatening disease caused by Salmonella Typhi bacteria. It spreads when someone consumes food or water that has been contaminated with feces (poop) from someone carrying the bacteria. About 12–27 million cases of typhoid fever occur worldwide every year.
About 350 culture-confirmed cases of typhoid fever in the United States are reported to CDC each year. Most of these cases occur among international travelers.
Symptoms of typhoid fever often include high fever, weakness, stomach pain, cough, and loss of appetite. Some people have diarrhea or constipation. Typhoid fever can be prevented through vaccination and safe food and water practices. Typhoid fever is treated with antibiotics, although most infections diagnosed in the United States cannot be successfully treated with the class of antibiotics called fluoroquinolones.
Dr Anna C. Phillips PhD CPsychol AFBPsS
Reader in Behavioural Medicine
School of Sport, Exercise & Rehabilitation Sciences
University of Birmingham
MedicalResearch.com: What is the background for this study? What are the main findings?
Dr. Phillips: We know that various factors can affect the response to vaccination and that older adults have a poorer response than younger people, i.e. they produce fewer antibodies. We also know that many immune messengers and important hormones have daily rhythms in their levels and wanted to test whether the antibody response to vaccination might also be affected by time of day. We randomised surgeries to giving morning or afternoon vaccinations and tested before and one month after the vaccination for levels of antibodies.
Two of the three flu strains (viruses) contained in the vaccine showed a higher antibody response in the morning than in the afternoon, up to 4 x higher to one of the strains (A/California) and 1.5 x higher to the B strain. None of the potential mechanisms we measured (immune messengers, hormones) seemed to be driving this effect.
Louise-Anne McNutt, PhD Associate Director, Institute for Health and the Environment
University at Albany, State University of New York
Jessica Nadeau, PhD Epidemiologist, University at Albany, State University of New York
Medical Research: What are the main findings of the study?
Response: The study found that about 25% of infants consistently deviated from the routine vaccine schedule recommended by the American Academy of Pediatrics (AAP). Alterations included either consistently refusing a recommended vaccine or reducing the number of vaccines given at each visit.
These deviations are generally associated with intent to use an alternative vaccination schedule.
Infants who did not follow the AAP recommended schedule were more likely to be unprotected against vaccine preventable diseases for a longer period of time. Only 1 in10 infants vaccinated on an alternative schedule were up-to-date at 9 months of age. Continue reading →