Rabies is a viral disease caused by Rabies Virus. Rabies is the most deadly disease known to mankind with an untreated death rate of 99%. Compared to Rabies, Ebola has a death rate of 50 to 90% (depending upon the variant).
Rabies is a zoonotic disease which means it is spread to humans through other animals, typically dog or bat bite. The virus is neurotropic i.e. it travels through the nervous system to the Central nervous system.
The symptoms of rabies include flu like symptoms, photophobia (sensitivity to light), hallucination, anxiety and hydrophobia (aversion to water). The best way to survive rabies is vaccination. As soon as a person is bitten by dog or any animal, it is advisable to get vaccinated. Rabies is a weird disease. With immediate vaccination after an animal bite, it is prevented in 100% of cases. But if untreated, it almost always results in death.
Jeanna, the first person to be treated with the Milwaukee protocol, is the first person to survive rabies after the onset of symptoms. Death in rabies is caused by temporary brain dysfunction. Thus to avoid death, in the Milwaukee protocol, the patient is put into a chemically induced coma and pumped full of antivirals. The coma suppresses brain activity and then the game is to wait and watch and hope that the body’s immune system fights off the rabies virus. Even this radical treatment has survival rate of only 8%.
Stress produces a steroid hormone (Glucocorticoid) known as Cortisol. Cortisol secretion is a natural response evolved to better deal with the live or death situations in our primitive jungle life. These stressors were expected to last for 30-60 seconds but the modern age with its variety of stresses has increased this duration to hours or even days. This causes considerable damage to the body and to the brain.
Cortisol counteracts the action of Insulin, the obvious evolutionary reason is to provide more glucose to the body in the time of stress. It lowers bone formation by accelerating excretion of potassium. It also enhances short term memory in cooperation with epinephrine but affects long term memory thus impairing learning. It shuts down reproductive system thus causing temporary infertility due to prolonged stress.
Caffeine increases Cortisol levels (Note to self: Avoid that extra cup!), Sleep deprivation increases Cortisol level (Note to self: Avoid that extra Criminal Minds episode!), Long travel increases Cortisol Level (Note to self: Take a house closer to the office!), Cortisol causes burnout (Note to Self: Avoid Cortisol!)
Glucocorticoids reduces the proliferation of T-Cells and also suppresses humoral immunity, thus reducing your natural immune system and making you susceptible to illness.
Disclaimer: As I have always maintained, do not take medical or for that matter any advice from a jobless “MBA” student like me. To put simply, I do not guarantee the accuracy of any information that I provide. And I am not a doctor or a microbiologist or a chemist or a PhD.
Antibiotic is a term coined by Selman Waksman in 1942 which means a product of a microorganism that is harmful to another microorganism. Selman, a Russian Immigrant to United States, won the 1952 Nobel prize for physiology or medicine for his discovery of Strepomycin, used for treatment of Tuberculosis.
Alexander Fleming in 1928 observed that a culture of Penicillium Notatum produces a substance that exhibits antibacterial properties. Florey, Chain and Fleming won the 1945 Nobel for the synthesis of Penicillin. Penicillin ushered in a new era in treatment of diseases and synthesis of new antibiotics.
Antibiotics are commonly classified based on their action, spectrum of bacteria that they work against and their chemical structure.
Mechanism of antibacterial action. Courtesy Wikipedia
The major classes of Antibiotics are as follows
Aminoglycocides – Action against gram negative bacteria. Mechanism of action is protein synthesis inhibition. Effective against bacteria like Escherichia Coli. e.g. Neomycin, synthesized by our very own Selman Waksman
Carbapenem – Broad spectrum beta-lactam antibiotic. Beta lactam indicates that they have beta lactam molecule at their core. Their mechanism of action is by attacking the bacterial cell wall. Other beta lactam antibiotics include Penicillins and cephalosporins. Carbapenems are the antibiotics of last resort. Bacteria containing NDM-1 (New Delhi Metallo – 1, Beta lactamase) enzymes are resistant to carbapenems. There are no other antibiotics capable to combat bacteria resistant to Cabapenem. Thus the appearance of NDM-1 poses a grave threat of pandemic. NDM-1 acts by breaking the Beta Lactam molecule at the core of these antibiotics thus making them ineffective. Coverage is broad spectrum. E.g. Imipenum
Cephalosporins like Carbapenems are broad spectrum, beta lactam antibiotics. E.g. Suprax.
Macrolide – They contain Macrolide ring in their molecule. Effective against infections like streptococcus and syphilis. E.g. Azithromycin (Throat infection, middle ear infection, tuberculosis, bronchitis, tonsilitis etc) Erythromycin.
Gram Staining is a method used to identify the type of the bacteria. The method was created by Hans Christian Gram, a Danish scientist. The method consists of using Crystal Violet chemical which ionises into CV+ and Cl- ions. CV+ enters into cell walls of bacteria and stains the cell purple. When Gram’s Iodine is added to the mixture, it forms large complexes with CV+ inside the cell. A decolorizing agent like Alcohol or Acetone is then added which dissolves the cell wall along with the CV-I complex in a gram negative bacteria while a gram positive bacteria keeps the CV-I complex because of the multilayered structure of its outer cell wall layer of Peptidoglycan. Thus the gram positive bacteria will retain the purple color while a gram negative bacteria will lose it. Another coloring agent like Safranin is added which gives a pink color to the gram negative bacteria.
Gram Negative Bacteria – Cyanobacteria, E. Coli, Salmonella.
Gram Positive Bacteria – Streptococcus (S. pneumoniae – Pneumonia), Staphylococcus, Clostridium (C. botulinum – Botulinum, C. tetani – Tetanus).
XDR-TB stands for eXtremely Drug Resistant Tuberculosis. One third of the world’s population is infected by TB bacteria but that does not mean that those individuals show symptoms. In most of them, the TB bacteria will lie dormant until the body’s immune system is compromised due to old age, HIV or other such causes. Normal TB is treated by a combination of four, first line drugs. Due to improper usage of these drugs, a resistant strain of TB called the MDR-TB (Most Drug Resistant – TB) is in the wild now.
The MDR-TB can still be treated by using second line drugs which are costlier and have more serious side effects. The patients needs to be isolated for longer duration and side effects include hallucinations and depression. The strain of bacteria that are resistant to even these last line of defense form the XDR-TB. These strains are currently seen in parts of Russia and South Africa.
Like the usual TB, XDR-TB also spreads through air when an infected person coughs or sneezes.
Treatment of XDR-TB is the same as for MDR-TB but the survival rate is lower and a much extensive regimen of antibiotics needs to be administered.
More research into finding an effective cure for these resistant variants is required. But since TB is more prevalent in the emerging world, the pharma giants do not have the same incentive to carry research on it like they have for more “rich” ailments like heart disease and cancer.