Epidemiology of Zygomycosis

Because zygomycosis is a rare infection, difficult to diagnose, and occurring in different patient populations with varied predisposing factors, epidemiology of this disease remains poorly understood. The only evaluation of incidence of zygomyco-sis among the general population has been published about 10 years ago after a population-based laboratory active surveillance performed in three counties of California, USA, during 1992-1993. Ten cases of zygomycosis have been reported for a total population of 2.94 million, which correspond to an incidence of 1.7 cases per million per year (Rees et al., 1998). Nevertheless, advances have been made during the past years, particularly in selected populations such as patients with malignancies although there have been no large-scale multicenter surveillance studies. Overall, these studies have reported an increase of the number of zygomy-cosis over time. In particular, analysis of the records of 5,589 patients who underwent hematopoietic stem cell transplantation from 1985 to 1999 at one center showed that the number of zygomycosis increased from seven cases in the period 1985-1989 to 15 cases in the period 1995-1999 (Marr et al., 2002). Similarly, in a large cancer center, 24 cases of zygomycosis have been reported over a 10-year period, with an increase of incidence from eight cases for 100,000 admissions during 1989-1993 to 20 cases for 100,000 admissions during 1994-1998 (Kontoyiannis et al., 2000). Interestingly all cases were diagnoses in patients with hematologic malignancy and none in patients with solid cancer. Of importance, since 2004 several publications have reported cases of breakthrough zygomycosis in patients receiving voriconazole as prophylaxis or empiric therapy (Marty et al., 2004; Siwek et al., 2004; Vigouroux et al., 2005; Oren, 2005; Kontoyiannis et al., 2005; Imhof et al., 2004). Voriconazole is known to have no activity against zygomycetes and this could explain the breakthrough infections. In a prospective case-control study in a cancer center it has been shown that voriconazole prophylaxis was an independent factor for zygomycosis (Kontoyiannis et al., 2005). Nevertheless, as recently highlighted (Kauffman, 2004), it is not clear if the use of voriconazole is directly responsible for the increased incidence of zygomycosis. It has to be noticed that the increase in the incidence of zygomycosis has started in the 1990s before the availability of voriconazole (Kontoyiannis et al., 2000; Marr et al., 2002), and that practices for management of patients with hematologic malignancy have changed with an increase frequency of graft-versus-host disease that requires aggressive immunosuppressive therapy (Kauffman, 2004).

Zygomycosis is acquired from environmental sources and there is no person to person transmission. Nevertheless, one should be aware that nosocomial outbreaks may occur and that grouped cases of zygomycosis should prompted investigations. Several outbreaks and pseudoepidemics have been reported in the past, and other reports have been published recently. An outbreak of gastric mucormycosis involving five patients in an intensive care unit, with an attributable mortality of 40%, was linked to the use of wooden tongue depressors contaminated with R. microsporus (Maravi-Poma et al., 2004). Outbreaks of cutaneous zygomycosis caused by R. oryzae and A. corymbifera have also been reported recently (LeMaile-Williams et al., 2006; Christiaens et al., 2005).

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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