Burden of disease from cryptosporidiosis

Abstract

Purpose of review: The global significance of cryptosporidiosis is widespread and far-reaching. In this review, we present recent data about strain diversity and the burden of disease, along with developments in therapeutic and preventive strategies.

Recent findings: Cryptosporidium is an emerging pathogen that disproportionately affects children in developing countries and immunocompromised individuals. Without a diagnostic tool amenable for use in developing countries, the burden of infection and its relationship to growth faltering, malnutrition, and diarrheal mortality remain underappreciated. Disease incidence is also increasing in industrialized countries largely as a result of outbreaks in recreational water facilities. Advances in molecular methods, including subtyping analysis, have yielded new insights into the epidemiology of cryptosporidiosis. However, without practical point-of-care diagnostics, an effective treatment for immunocompromised patients, and a promising vaccine candidate, the ability to reduce the burden of disease in the near future is limited. This is compounded by inadequate coverage with antiretroviral therapy in developing countries, the only current means of managing HIV-infected patients with cryptosporidiosis.

Summary: Cryptosporidiosis is one of the most important diarrheal pathogens affecting people worldwide. Effective methods to control and treat cryptosporidiosis among high-risk groups present an ongoing problem in need of attention.

Figure 1

a: Hospital based cryptosporidiosis prevalence rates among children under 6 years with diarrhea in developing countries** ** HIV status was unknown or unreported in these studies; unless otherwise noted, primary detection of cryptosporidiosis was by microscopy with acid fast staining ^a Detection by PCR b: Urban Hospital and HIV clinic based cryptosporidiosis frequency rates among HIV-infected adult patients with diarrhea in developing countries*** *** Unless otherwise noted, primary detection of cryptosporidiosis was by microscopy with acid fast staining, ± = pediatric patients included, Φ = only 80% of HIV-infected patients in this study had diarrhea, ^X = HIV-infected controls without diarrhea, ^Y = HIV-negative controls, frequency of cryptosporidiosis was 0, ^Z = HIV-negative controls with diarrhea, • Studies above line included controls, IF = immunofluorescent staining, frequency 18.4% with acid fast staining