A new study has opined that people with less education could be more vulnerable to contracting H1N1 infection and the vaccine might be less effective in them compared to those who earned a high school diploma.
In the study, researchers focused on CMV, a latent virus in the herpes family. Infection is common but the majority of people aren't symptomatic because the immune system keeps the virus under control.
But people of lower income and education lose immune control more easily, probably due to stress.
"What is going on with the dramatic (downturn) in the economy could actually translate into people's susceptibility to these diseases," said study's co-author Jennifer Dowd.
Previous studies have shown that high levels of CMV antibodies make it tougher for the elderly to fight new infections like H1N1, and hampers the body's immune response to the flu vaccine.
The University of Michigan study suggests that lower socioeconomic status may make it tougher even for adults of all ages to fight new infections and may make the flu vaccine less effective.
"We're showing that the ability to keep CMV under control varies by income and education even at much younger ages, and this could have implications for the ability to fight new infections like H1N1 for all ages, not just the elderly," Dowd added.
"We looked at CMV because it is an infection that is not cleared from the body but rather persists in a latent state with periodic reactivations in generally healthy individuals," said co-author Allison Aiello, assistant professor of epidemiology at University of Michigan SPH.
"Immune response to CMV may serve as a marker of general immune alterations and is therefore an important indicator of health risks," Aiello added.
The study appears in an upcoming issue of the journal Epidemiology.