Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Malaria is an infectious disease caused by a parasite, Plasmodium, which infects red blood cells. Malaria is characterized by cycles of chills, fever, pain, and sweating. Historical records suggest
malaria has infected humans since the beginning of mankind. The name "mal aria" (meaning "bad air" in Italian) was first used in English in 1740 by H. Walpole when describing the disease. The term was shortened to "malaria" in the 20th century. C. Laveran in 1880 was the first to identify the parasites in human blood. In 1889, R. Ross discovered that mosquitoes transmitted malaria. Of the four common species that cause malaria, the most serious type is
Plasmodium falciparum malaria. It can be life-threatening. However, another relatively new species,
Plasmodium knowlesi, is also a dangerous species that is typically found only in long-tailed and pigtail macaque monkeys. Like
P. falciparum, P. knowlesi may be deadly to anyone infected. The other three common species of malaria (P. vivax, P. malariae, and
P. ovale) are generally less serious and are usually not life-threatening. It is possible to be infected with more than one species of
Plasmodium at the same time.
Currently, about 2 million deaths per year worldwide are due to Plasmodium infections. The majority occur in children under 5 years of
age in sub-Saharan African countries. There are about 400 million new cases per year worldwide. Most people diagnosed in the U.S. obtained their infection outside of the country, usually while living or traveling through an area where malaria is endemic.
Three main factors determine treatments: the infecting species of Plasmodium parasite, the clinical situation of the patient (for
example, adult, child, or pregnant female with either mild or severe malaria), and the drug susceptibility of the infecting parasites. Drug susceptibility is determined by the geographic area where the infection was acquired. Different areas of the world have malaria types that are resistant to certain medications. The correct drugs for each type of malaria must be prescribed by a doctor who is familiar with malaria treatment protocols. Since people infected with
P. falciparum malaria can die (often because of delayed treatment), immediate treatment for
P. falciparum malaria is necessary.
Kidney failure can occur from an acute event or a chronic condition or disease. Prerenal kidney failure is caused by blood loss, dehydration, medication.
Headaches can be divided into two categories: primary headaches and secondary headaches. Migraine headaches, tension headaches, and cluster headaches are
The spleen enlarges if it is asked to do excessive work in filtering or manufacturing blood cells, if there is abnormal blood flow to it, or if it is invaded
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy.
Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered
Neutropenia is a marked decrease in the number of neutrophils, neutrophils being a type of white blood cell (specifically a form of granulocyte) filled
Chronic cough is a cough that does not go away and is generally a symptom of another disorder such as asthma, allergic rhinitis, sinus infection, cigarette
Nausea is an uneasiness of the stomach that often precedes vomiting. Nausea and vomiting are not diseases, but they are symptoms of many conditions. The
Jaundice is a yellowish staining of the skin and whites of the eyes (sclerae) with bilirubin, the pigment found in bile. Jaundice can be an indicator of
Fatigue can be described in various ways. Sometimes fatigue is described as feeling a lack of energy and motivation (both mental and physical). The causes
G6PD deficiency (Glucose 6-phosphate dehydrogenase) leads to a condition called hemolytic anemia. Causes of G6PD deficiency is an abnormal gene located
Medical shock is a life-threatening medical condition. There are several types of medical shock, septic shock, anaphylactic shock, cardiogenic shock, hypovolemic
Influenza (flu) is a respiratory illness caused by a virus. Flu symptoms include fever, cough, sore throat, runny nose, headache, fatigue, and muscle aches.
Alpha thalassemia is a disorder in which the alpha globin protein is underproduced. There are two pairs of genes that carry the code for the alpha chains
Drug resistance (antimicrobial resistance) is the ability of bacteria, fungi, parasites, and viruses to grow, even in the presence of a drug that would
Travelers should prepare for their trip by visiting their physician to get the proper vaccinations and obtain the necessary medication if they have a medical
Chronic cough is a cough that persists. Chronic cough is not a
disease in itself; rather it is a symptom of an underlying condition. Chronic
cough is a common
problem and the reason for many doctor visits. "...
