According to a press release from publisher Wiley-Blackwell, “The team of researchers at Waikato Hospital and the Universities of Waikato and Otago, measured vitamin D in the blood samples of 112 adult patients admitted with community acquired pneumonia during the winter at the only acute-care hospital in Hamilton, New Zealand.”
When looking at outcomes from that group, the researchers found that Vitamin D deficiency correlated with outcomes.
The Wiley-Blackwell press release notes: “The researchers found that Vitamin D deficiency was associated with higher mortality within the first 30 days after hospital admission for pneumonia. The association between vitamin D deficiency was not explained by patient age, sex, comorbidities, the severity of the systemic inflammatory response, or other known prognostic factors.”

University of Eastern Finland study showed that low serum vitamin D levels are a risk factor for pneumonia. The risk of contracting pneumonia was more than 2.5 times greater in subjects with the lowest vitamin D levels than in subjects with high vitamin D levels. The results were published in Journal of Epidemiology and Community Health

http://www.sciencedaily.com/releases/2013/04/130430091640.htm
http://www.medwirenews.com/43/105140/Infectious_diseases/Vitamin_D_status_optimization_could_cut_pneumonia_cases.html