CDC suggests that older adults may have pre-existing antibodies to combat H1N1
ATLANTA A study published last week in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report determined that older adults might have some pre-existing antibodies against the novel H1N1 virus, which would explain why this new virus is more prominent among younger, healthier populations.
Those antibodies may have come from past flu shots.
“The presence of preexisting antibody may be due to previous exposure through infection or vaccination to an Influenza A (H1N1) virus that more closely related to this novel H1N1 virus than the contemporary seasonal H1N1 strains that we had,” stated Anne Schuchat, director of immunizations and respiratory diseases. “We don’t know yet what that will mean in terms of actual immunity or clinical protection. It’s interesting that the laboratory findings we’re reporting seem to correlate with the epidemiologic data that we have so far that suggests most of the illnesses we’re seeing have occurred in younger people and have spared the elderly, who are at great risk for seasonal influenza.”
Of the cases reported to the CDC that have undergone laboratory testing, 64% are occurring in people between 5 and 24 years of age. Conversely, just about 1% of cases are in people over 65. “So the vast majority are in younger persons, and the biggest proportion of those are people in the 5- to 24-year-old age group,” Schuchat said.
The results presented in the study found that the current seasonal influenza vaccine provides little or no immune benefit against the novel H1N1 flu virus. Further, the laboratory results, while interesting, do not necessarily indicate that seniors may have some level of immunity to the H1N1 virus currently circulating, Schuchat said.
Study finds link between vitamin D deficiency, bacterial vaginosis
BETHESDA, Md. There may be a link between vitamin D deficiency and bacterial vaginosis, a vaginal infection that is common among pregnant women and can lead to complications.
According to data to be published in the June 2009 issue of the Journal of Nutrition, researchers tracking 469 pregnant women found that 41% of those women had BV, and that the prevalence of BV decreased as vitamin D concentration increased.
Researchers concluded that vitamin D insufficiency is associated with BV in the first four months of pregnancy. Further, poor vitamin D status may contribute to the strong racial disparity in the prevalence of BV in U.S. women. Controlled intervention trials will be needed to confirm this hypothesis, the researchers suggested.
Vitamin D intake can help asthma, COPD patients
SAN DIEGO Vitamin D may slow the progressive decline in the ability to breathe that can occur in people with asthma, as a result of human airway smooth muscle proliferation, according to researchers at the University of Pennsylvania in a study released Wednesday.
The group found that calcitriol, a form of vitamin D synthesized within the body, reduced growth-factor-induced HASM proliferation in cells isolated from both persons with asthma and from persons without the disease. The proliferation is a part of process called airway remodeling, which occurs in many people with asthma, and leads to reduced lung function over time.
The researchers believe that by slowing airway remodeling, they can prevent or forestall the irreversible decline in breathing that leaves many asthmatics even more vulnerable when they suffer an asthma attack.
“Calcitriol has recently earned prominence for its anti-inflammatory effects,” stated Gautam Damera, who presented the research at the American Thoracic Society’s 105th International Conference on Wednesday. “But our study is the first to reveal the potent role of calcitriol in inhibiting ASM proliferation.”
The investigators have also conducted experiments to determine whether calcitriol, which is currently used to treat psoriasis, could be an effective therapy for COPD.
Although preliminary, their data shows that calcitriol appears to reduce pro-inflammatory cytokine secretions in COPD. As with asthma, the researchers believe, calcitriol may also have the added benefit of slowing, if not stopping, the progression of airway remodeling. Others in the field believe calcitriol may also have the potential to inhibit the development and growth of several types of cancer.