Pneumocystis Pneumonia

A light micrograph of a smear containing Pneumocystis jirovecii (dark purple cells) obtained from human lung tissue and stained with toluidine blue. (credit: Centers for Disease Control and Prevention) OpenStax Microbiology A type of pneumonia called Pneumocystis pneumonia (PCP) is caused by Pneumocystis jirovecii. Once thought to be a protozoan, this organism was formerly named P. carinii but it has been reclassified as … Continue reading Pneumocystis Pneumonia

The Blastomycosis

(a) These skin lesions are the result of disseminated cutaneous blastomycosis. (b) A differential interference contrast micrograph of B. dermatitidis yeast cultured on blood agar. (credit a: modification of work by Centers for Disease Control and Prevention) OpenStax Microbiology Blastomycosis is a rare disease caused by another dimorphic fungus, Blastomyces dermatitidis. Like Histoplasma and Coccidioides, Blastomyces uses the soil as a reservoir, and … Continue reading The Blastomycosis

The Influenza

Source: OpenStax Microbiology OpenStax Microbiology Commonly known as the flu, influenza is a common viral disease of the lower respiratory system caused by an orthomyxovirus. Influenza is pervasive worldwide and causes 3,000–50,000 deaths each year in the United States. The annual mortality rate can vary greatly depending on the virulence of the strain(s) responsible for seasonal epidemics.  Influenza … Continue reading The Influenza

The Coccidioidomycosis

(a) This patient has extensive facial lesions due to a disseminated Coccidioides infection. (b) This fluorescent micrograph depicts a spherule of C. immitis containing endospores. (credit a, b: modification of work by Centers for Disease Control and Prevention) OpenStax Microbiology Infection by the dimorphic fungus Coccidioides immitis causes coccidioidomycosis. Because the microbe is endemic to the San Joaquin Valley … Continue reading The Coccidioidomycosis

SARS and MERS

By Cynthia Goldsmith/Maureen Metcalfe/Azaibi Tamin - https://www.cdc.gov/coronavirus/mers/photos.html, Public Domain, https://commons.wikimedia.org/w/index.php?curid=26433945 OpenStax Microbiology Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) are two acute respiratory infections caused by coronaviruses. In both cases, these are thought to be zoonotic infections. Bats and civet cats are thought to have been the reservoirs for SARS; camels seem … Continue reading SARS and MERS

Pneumococcal Pneumonia

(a) This micrograph of Streptococcus pneumoniae grown from a blood culture shows the characteristic lancet-shaped diplococcal morphology. (b) A colorized scanning electron micrograph of S. pneumoniae. (credit a: modification of work by Centers for Disease Control and Prevention; credit b: modification of work by Janice Carr, Centers for Disease Control and Prevention) OpenStax Microbiology The most common cause … Continue reading Pneumococcal Pneumonia