the disease, typically through autosomal-dominant inheritance. Given the rarity of the disease, it is not yet possible to generalize on disease prevalence among ethnic and racial groups. CVID shortens the life-span; but no study currently has a median age recorded. One study suggests the median age of death for men and women is 42 and 44 years old, respectively, but most patients involved in the study are still alive. Those people with accompanying disorders had the worst prognosis (50% survival 33 years after diagnosis) and those people with only CVID-caused frequent infections had the longest survival rates, with another study stating a life expectancy almost equalling that of the general UK population. Additionally, people with CVID with one or more noninfectious complications have an 11 times higher risk of death as compared to people with only infections. History Immunodeficiencies comprise many diseases and are genetic defects affecting the immune system. There are roughly 150 immunodeficiencies spanning over 120 genetic defects. Charles Janeway Sr. is generally credited with the first description of a case of CVID in 1953. The case involved a 39-year-old who had recurrent infections, bronchiectasis, and meningitis. CVID has since emerged as the predominant class of primary antibody deficiencies. It is thought to affect between 1 in 25,000 to 1 in 50,000 people worldwide. Though described in 1953, there was no standard definition for CVID until the 1990s, which caused widespread confusion during diagnosis. During the 1990s, the European Society for Immunodeficiency (ESID) and Pan-American Group for Immunodeficiency (PAGID) developed diagnostic criteria, including minimum age of diagnosis and the need to exclude other conditions, to describe the disease. These criteria were published in 1999 and since that time, some aspects, like increasing the minimum age, have been changed. Research Current research is aimed at studying large cohorts of people with CVID in an attempt to better understand age of onset, as well as mechanism, genetic factors, and progression of the disease. Funding for research in the US is provided by the National Institutes of Health. Key research in the UK was previously funded by the Primary Immunodeficiency Association (PiA) until its closure in January 2012, and funding is raised through the annual Jeans for Genes campaign. Current efforts are aimed at studying the following: Causes of complications. Little is known about why such diverse complications arise during treatment. Underlying genetic factors. Though many polymorphisms and mutations have been