Australian study links sunlight exposure to tuberculosis rates
The research, which was presented at the Annual Scientific Meeting of the Australian Society for Infectious Diseases in Canberra, found that rates of TB incidence increased up to 37 percent following the darker winter months when there is less light to aid in the body's production of vitamin D, according to ExchangeMagazine.com.
The study was conducted by Dr. Jennifer MacLachlan and Dr. Benjamin Cowie of the Victorian Infectious Diseases Reference Laboratory, Melbourne, and the University of Melbourne.
Experts have hypothesized that seasonal variation in TB incidence rates may occur because of an association between vitamin D deficiency and the reactivation of the latent form of TB infection. MacLachlan and Cowie found that TB cases peaked in Australia during September through December, which are two to three months after that country's winter.
The researchers found that notification rates in Australia were 24 percent higher in that period than during the rest of the year. The notification rates during the period increased to 37 percent in Australia's Southern states, where seasonal swings in sunlight levels are the highest, according to ExchangeMagazine.com.
The researchers said current recommendations to avoid sun exposure in Australia may need to be balanced to take into account the need to maintain an adequate level of vitamin D in the body.