Relapse is rare but does occur even after a full course of treatment. Prognosis
Published estimates of the case fatality rate for blastomycosis have varied from 4% to 78%. A 2020 meta-analysis of published studies found an overall mortality rate of 6.6%. This rose to 37% for immunocompromised patients and 75% for patients with ARDS. A 2021 analysis of 20 years of disease surveillance data from the five US states where blastomycosis is reportable found an overall mortality rate of 8% and a hospitalization rate of 57%. These numbers may be affected by the under-reporting of mild cases. Epidemiology
Incidence in most endemic areas is about 0.5 per 100,000 population, with occasional local areas attaining as high as 12 per 100,000. Most Canadian data fit this picture. In Ontario, Canada, considering both endemic and non-endemic areas, the overall incidence is around 0.3 cases per 100,000; northern Ontario, mostly endemic, has 2.44 per 100,000. Manitoba is calculated at 0.62 cases per 100,000. Remarkably higher incidence was shown for the Kenora, Ontario region: 117 per 100,000 overall, with aboriginal reserve communities experiencing 404.9 per 100,000. In the United States, the incidence of blastomycosis is similarly high in hyperendemic areas. For example, the city of Eagle River, Vilas County, Wisconsin, which has an incidence rate of 101.3 per 100,000; the county as a whole has been shown in two successive studies to have an incidence of about 40 cases per 100,000.
Causes
This condition is caused due to incomplete fusion of both sides of the nose during embryonic life.This anomaly is highly hereditary: autosomal dominant and autosomal recessive inheritance patterns have been observed in multiple families.If the bifid nose is accompanied by abnormalities of the anorectal and renal systems, it may be part of a different separate genetic disorder (which is characterized by overlapping toes, renal adysplasia and variable anorectal anomalies) that is caused by autosomal recessive mutations in the FREM1 gene. Treatment
Generally, sutures and rhinoplasty can be done in order to get rid of a bifid nose tip (though what surgery should be done depends on the severity of the cleft nose). Open W-shaped surgical incisions have also proven to be effective. Surgery is usually done before the age of 5. Prevalence
This birth anomaly affects less than 0.0008% of people worldwide, making it the most common midline craniofacial cleft.8% of people with bifid nose also have hypertelorism. Bifid nose as a hereditary trait
Two forms of inheritance pattern for bifid noses have been described: autosomal recessive and autosomal dominant. One case per inheritance pattern follows:

Autosomal dominant: Anyane-Yeboa et al. (1984) describes 5 women from a 3-generation American family. Karyotypes and skull X-rays done on the younger sisters gave normal results. Autosomal recessive: Boo-Chai et al. (1965) describes 3 siblings from a continental Indian family. History
This condition was first described in medical literature in 1939 by Esser et al. when they described 5 children (4 siblings and a male first-cousin of theirs) from a single family.