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Last updated May 26, 1999
The Cascade Hospital is a resource website designed specifically to help FANFIC and other FICTION WRITERS who want to make their stories more medically authentic. It is NOT for people seeking answers to personal medical questions -- that is a job for your private physician.
Division of Infectious
Disease
~ Infectious diseases -- bacteria, viruses, parasites ~
Please read the Sentinel and Medical Disclaimers.
Flu virus
Bacterial meningitis
Malaria
Ebola virus
Rabies
Food poisoning
Pneumonia
Antibiotic-resistant organisms
Flu virus -- detection, does an infected person always get sick?
You can have a flu virus (or any virus probably, for that matter) in your system and not get sick. We are exposed to lots of viruses every day and they don't all make us sick because our immune system kills them before they can do any damage. That is why people who have a non-functioning immune system (such as those with AIDS) get sick from a lot of different things that normal people don't get because they can't clear viruses, bacteria, or parasites from their body well.
As for whether you can detect a virus in someone's blood, well, there is such a thing as a viral culture. You take the body fluid (blood, mucus, urine, whatever) that you think the virus is in and add it to a cell culture of human cells or some other kind of cells that the virus will grow in and kill (viruses are very specific in the kinds of cells they infect). If the stuff you add ends up killing the cells you added it to, then you conclude that you probably have a virus in that body fluid. This is rarely done, however, because a viral culture is time consuming and many hospital laboratories do not do such high-tech culturing. The CDC (Centers for Disease Control) has many ways of doing this, but they're different than your ordinary hospital. Also, doctors can't afford to wait around for the results of the test to come back, nor do they want to order really expensive tests if they don't have to. Another thing is that there aren't very many medicines out there that actually treat viral infections (unlike bacterial infections which we have antibiotics for), so knowing the exact virus isn't always helpful in treating a patient.
The way doctors detect viruses more often is through measurement of antibodies to the virus. That is how we detect HIV and viral hepatitis -- not through direct measurement of the virus, but through whether the person has antibodies to it (which means they've been exposed to the virus and their body reacted to it by making antibodies). There are also tests for detecting the presence of viral particles. There is a test for hepatitis surface antigen (a piece of the virus) and for p24 antigen for HIV. As for the flu virus, well, doctors do not get antibody levels or viral particle levels for the flu virus because it isn't cost effective, and it's just as easy to diagnose the flu just by looking at the person and getting them to tell you about their symptoms. The CDC has ways of culturing the flu virus and analyzing it every year for its structure (they are especially interested in the neuraminidase and hemaglutinin enzymes) which continually mutate. They use this information to find out if a new flu virus has appeared (such as that chicken virus from China) and they use it to predict what the next year's flu vaccine should be. But physicians do not ordinarily use these tests to diagnose or treat the flu.
Bacterial meningitis is an infection of the meninges or the lining of the brain. The two main organisms that cause meningitis in adults are Neisseria meningitidis and Streptococus pneumoniae. Both cause a nasty disease. Neisseria meningitis happens more often to young adults in institutional settings such as military barracks, dormitories, etc. Streptococcus can happen to anyone.
How is it contracted?
Neisseria meningitis starts with a person becoming a "carrier"
of the bacteria in their nose and throat. Many people walk around with
this bug living in their nose and throat and never know it and never get
meningitis. No one really knows why some people develop meningitis. Somehow
the bug invades the bloodstream and travels to the lining of the brain
and sets up housekeeping. Streptococcal meningitis can happen when a person
has another strep infection like pneumonia (not strep throat, though) and
the bug invades the blood and travels to the lining of the brain.
What are the symptoms?
The onset of meningitis is often very rapid, especially in younger people.
Over a day or even hours, the person "doesn't feel good" and
gets a headache which can be pretty bad. Then they get a stiff neck (can't
bend their head forward or backward or to the side without it hurting).
They also get a high fever. Nausea and vomiting are also common. This can
progress to lethargy and even unconsciousness. These symptoms are the same
for pretty much any meningitis. In Neisseria meningitis, people can also
develop a rash over the body (usually starts on arms and legs, then spreading
to the trunk). The rash is called a petechial rash, which means it looks
like a bunch of purple spots and splotches where little blood vessels have
broken open and caused little bleeds under the skin. This rash is a very
bad sign. In Neisseria meningitis, people can also go into shock from massive
bleeding--their blood pressure becomes very unstable and drops. Hopefully
they've gotten to a hospital before this stage, but sometimes the disease
progresses so rapidly that the person can be fine in the ER and then crash
in an hour and even die.
How would you diagnose it?
If any person comes into the ER complaining of fever, stiff neck, and headache,
they automatically get a spinal tap ("LP", or lumbar puncture,
is the medical term). That involves the person laying on their side and
the doctor putting a needle into their lower back and getting a sample
of the fluid that bathes the spinal cord and brain. Normally the fluid
should be clear. In bacterial meningitis the fluid is often cloudy. Laboratory
tests on the fluid tell the doctor if there are any bugs in it, what the
bugs are, and eventually what drugs the bugs can be killed by. Oh, on the
physical exam, a doctor would ask the patient to try and move their neck
around (if they can't, bad sign). There are also two maneuvers called the
Kernig test and the Brudinzski test. I always forget which is which, but
one involves telling the patient to bend their knee up to their chest (while
laying on their back). If that hurts, it's a pretty suspicious sign for
meningitis.
How is it treated?
IV (intravenous) antibiotics. The meningitis drug is called Rocephin, and
you start giving it to the patient immediately, before you know the results
of the LP. The person would also be given some IV fluids to make sure they
don't get too dehydrated, but you also don't want to give too much because
that could contribute to swelling in the brain. If the person goes into
shock, they get supportive therapy--oxygen, intubation if they stop breathing,
and drugs called "pressors" like dopamine if their heart stops
working well. If the person goes into shock, the prognosis is very poor.
Many people die. Many people with meningitis come in looking pretty sick,
so they get put in the ICU until they get better. Wherever they are put
in the hospital, many hospitals have a policy of putting the patient in
an isolation room (by themselves, anyone going in has to wear mask, gown,
and gloves) because if they have Neisseria meningitis it can be very contagious
at first. At my hospital it is for the first 24 hours of antibiotics.
How would recovery go?
That depends on how sick the person gets from the meningitis. If all they
really have is a fever, stiff neck, and headache, they could be feeling
better in a matter of days (2 or 3 if they're lucky), and the symptoms
usually improve within hours of starting the antibiotic. If they end up
going into shock, well, if they don't die, they could be in the ICU for
weeks depending on how long it takes them to recover. The standard treatment
is usually at least 10 days of IV antibiotics. The person can either stay
in the hospital for this, or they can go home when they feel better with
a special IV line called a PICC line and have a home nurse come and help
give them the antibiotics for the full course.
Are there any standard complications from the illness or the treatment?
Thank goodness most people with meningitis do not have lasting complications
from the illness. They get better, go home, and don't have any more problems.
Unfortunately, there are a few dreaded complications--the worst one is
death, which I've already said happens more often if the person goes into
shock. It's hard to predict which people are going to go into shock. It
could happen to anyone. Meningitis can cause the pressure on the brain
to increase, and the brain may swell. This can damage the brain tissue
itself and cause neurological deficits-- anything from deafness, blindness,
problems with memory, personality, motor functions, you name it. I took
care of a baby who got meningitis and she developed seizures from it and
a lot of neurological problems--it was very sad. These possible complications
make meningitis one of the most feared diseases one can have. Even though
it is treatable, you can still die from it, even if you get the antibiotics.
People with meningitis look very sick and it is very scary for family members
and friends to see their loved one so sick.
Ah yes, I remembered one more thing. If the person ends up having Neisseria meningitis, all their close personal contacts--family members, co-workers, roommates, everyone in the school class or daycare if they're a kid--have to be given a antibiotic drug (pill) called Rifampin for two days to kill off any bugs in any possible carriers. The doctor can write prescriptions for all of these people, but they have to be told that they must go to some doctor and get the Rifampin. Rifampin is a fun little drug to take (not really) because it happens to turn all your body secretions (urine, tears) a very bright orange. So you have to warn people about that or they freak out. The stain is so strong it can permanently stain contact lenses orange. Any other kind of meningitis does not require giving close contacts a drug.
Oh, another name for Neisseria meningitis is "meningococcal meningitis". The strep one is also called "pneumococcal meningitis."
Malaria is a disease where a parasite called Plasmodium infects the blood of a person and basically sets up shop, living and reproducing in the blood. You get malaria by being bitten by an Anopheles mosquito with malaria. The mosquito got it by biting another person with malaria and sucking their blood. These mosquitoes are present in almost all countries in the tropics and subtropics. Anopheles mosquitoes bite during nighttime hours, from dusk to dawn.
There are four kinds of malaria, caused by four different strains of Plasmodium -- suffice it to say that one kind is very, very, bad and life-threatening, and the others are more chronic problems that tend to relapse. The bad one is caused by Plasmodium falciparum and is considered a medical emergency, life-threatening.
After the mosquito bite, the person is fine for about 1 week while the parasite goes to the liver and reproduces. After one week, the parasite's children travel out of the liver to the person's blood stream and invade red blood cells. This causes paroxsyms of malaria -- high fever, sweats, chills, headache, muscle ache, and malaise. Early stages of malaria may resemble the onset of the flu. Apparently it starts with the chills and the whole attack lasts 1 to 2 hours. Then the person feels better. It takes 48 hours for the next batch of parasites to emerge from the liver and cause another attack of fever and chills. This goes on basically until the person dies or gets treated with the proper medicine.
The extra-bad kind, P. falciparum malaria, has extreme fevers (up to 107 degrees), affects the brain, and causes massive destruction of the person's red blood cells. The person's urine turns dark (black) because so many red blood cells are being destroyed. This can cause kidney failure and death from lack blood or kidney failure, or the fevers cook your brain. Not nice.
Malaria symptoms can develop as early as 6-8 days after being bitten by an infected mosquito or as late as several months (up to 6 months or even more) after departure from a malarious area, after antimalarial drugs are discontinued.
Between attacks, a person feels a lot better than during the attacks, but they probably don't feel totally great -- probably tired, weak, low energy. Since their blood cells are being destroyed by the parasite, patients develop anemia (thus tired, weak, etc.).
If a person goes untreated, especially if it's the really bad kind of malaria, they will die. If it's one of the types that isn't so bad, they'll probably be chronically ill until they get treated. I think it's pretty hard for a normal person's immune system to get rid of the malaria infection without help from drugs.
Current treatment: the main drug for malaria is called chloroquine (relative of quinine) trade name Aralen. It works for all kinds of malaria that aren't "chloroquine-resistant". Unfortunately, more and more malaria is resistant to chloroquine, which means the parasite isn't killed by chloroquine. And bummer, most resistant malaria is the extra-bad kind -- P. falciparum. For chloroquine-resistant malaria, the drug is called mefloquine (trade name Larium). Larium makes your stomach upset and can also cause dizziness. My teacher says that he felt awful when he took the medicine, but I guess some people don't have a problem.
There's also another drug called Primaquine that you can take to prevent relapses.
Once a person has recovered, they can be reinfected, as far as I can understand. I don't think you have immunity.
Relapses happen with the other kinds of malaria (basically with P. falciparum you either get over it totally or die.), and I think it's pretty common. Relapses happen when some of the parasite isn't totally killed off by the medicine, and it hangs out in your liver until it decides to come out again. You can get relapses over several years (2-3 years for P. ovale and 6-8 years for P. vivax). I think the relapses are pretty much the same severity as the initial attacks. You have to take medicine again to stop the attack.
Current places in the world where malaria is a problem: Basically anywhere in the third world tropics and subtropics. Malaria is common in central and south america (jungles especially), and most of Africa. I think some in Asia, too, but I'm not sure which countries exactly -- probably south-east Asia. You have to go to a place where Anopheles mosquitos live, since they're the things that pass the bug from person to person. Malaria is rare in the U.S., but you do see it occasionally, mostly in immuno-compromised people (like AIDS), and IV drug users that share needles (they can pass the parasite that way).
Some other things you might be interested in for malaria...
Prevention: The most important thing is to avoid mosquitos. To reduce mosquito bites travelers should remain in well-screened areas, use mosquito nets, and wear clothes that cover most of the body. Travelers should also take insect repellent with them to use on any exposed areas of the skin. The most effective repellent is DEET, the active ingredient in most insect repellants.
Also, people traveling to areas with malaria should also take preventive medicine -- chloroquine once a week, or Larium once a week if the area is a chloroquine-resistant area. They should start taking the medicine one week before they enter the area, weekly during the whole time they're in the area, and then for 4 weeks after they leave the area. They should be instructed about the symptoms of malaria and know to get medical help immediately if they develop symptoms. It is also important to know that even if you take these drugs as a preventive measure, you can still get malaria.
A really good website that might be helpful is the CDC's website. They have a lot of information there on all kinds of infectious diseases, and a special section for travel information. Their malaria section is under "Travelers Health" at the bottom of the section. I got some of the information above at their site. It's really good, written for lay people and medical professionals. They have a travel page where you can say where you're going in the world, and they'll tell you what vaccines and drugs you need, how to prevent traveler's diarrhea, all sorts of neat stuff.
The Ebola virus is spread by close personal contact with blood or body fluids of a person with an active infection (very ill) with the disease. I do not know if the Ebola virus would have been spread very effectively through massive airborne release as Brackett threatened to do in Rogue. The infection begins somewhat like the flu (fever, muscle aches), about a week after exposure. It can progress to a rapidly fatal hemorrhagic diathesis, meaning that your blood basically no longer clots and you start bleeding from every orifice of your body (intestinal tract, mucous membranes, etc.) The person dies from massive loss of blood.
Would Brackett have been able to obtain it as easily as he did in the episode? I doubt it (though I don't know for sure). The CDC (Centers for Disease Control) takes all samples of infectious particles (bacteria, viruses, whatever) very seriously, as would (I hope) all institutions who wished to do scientific research on all fatal substances with potential for biogenic warfare. Though I have not worked in a lab or company handling such substances, I'm sure security is much more strict than the episode showed Rainier's security to be.
For more information on Ebola, I recommend the CDC's National Center for Infectious Disease page on the Ebola virus, which gives some real basic info (what it is, how you get it, symptoms, what was up with the previous outbreak, etc.) in concise, easy-to-understand layperson language.
Rabies -- treatment, need for vaccine
If a person gets bitten by an animal, usually the animal must be caught. They try to find out if the animal has been vaccinated for rabies or not. If it's displaying behavior that is rabid or supicious for rabies, it is usually sacrificed and tested. If it's not acting particularly funny, then it may be observed for 10 days.
As for the person that got bit, the decision on whether or not to give rabies shots depends on the nature of the biting animal (is it obviously or suspiciously rabid), whether or not the animal was vaccinated for rabies and whether it can be caught for testing, the manner of attack, and the severity of the wound. Also extremely important are the prevalence of rabies in the area and especially advice from public health officials -- particularly if the animal was a wild animal and/or couldn't be caught. Doctors will generally contact the local public health department and consult with them on whether or not the person is at risk for getting rabies.
Rabies shots are actually two kinds of medicine -- one is a rabies vaccine and one is rabies immune globulin. The rabies virus must travel from the site where the person was bitten up the nerves to the brain where the encephalitis occurs (hydrophobia, etc.), and the virus travels very slowly. The incubation period is usually from 2 to 16 weeks. Because the virus moves so slowly, it is important to give the vaccine "after the fact" (called "postexposure prophylaxis") because you still have time to induce immunity in the victim before the virus reaches the brain and sets up the fatal infection.
The vaccine induces the body to produce antibodies to the rabies virus so it can kill it before it reaches the brain, and the immune globulin is a solution of pre-made human antibodies (the rabies virus is actually injected in very dilute solutions into real people who have built up a tolerance to the rabies virus ("hyperimmunized") and the antibodies from their blood are extracted!). You need to get 5 shots of the vaccine and some immune globulin if you haven't been previously immunized for rabies. According to the CDC, the directions are as follows:
Assuming the person wasn't immunized before, after you wash the wound out really good, the person should get a dose of rabies immune globulin (amount determined by the person's weight), with half of the amount injected at the bite site and the other half given as a shot in the arm (just like a tetanus shot). Then they also need 5 doses of the rabies vaccine, also given in the arm like a tetanus shot. The first dose is given when you first see the patient, then the next 4 doses on day #3, 7, 14, and 28. So the entire series is finished within 4 weeks of the attack. I don't think this shot is a whole lot more painful than other intramuscular shots in the arm like a tetanus shot.
If the person has been immunized for rabies before, you don't give the immune globulin and you give only 3 shots of the vaccine.
The new rabies vaccine they are using now (since the 1980's in the U.S.) is much nicer than the old vaccine which I think they used to give in the stomach and you had to get a shot every day for 14 to 21 days! Ouch! This old vaccine is still used in many other countries and has a higher risk for encephalomyelitis as a side effect, which is a nasty brain inflammation which you do not want.
Side effects for the new rabies vaccine are as follows: Persons may experience local reactions (30-70% of recipients) such as pain, erythema, and swelling or itching at the injection site, or mild systemic reactions (20% of recipients), such as headache, nausea, abdominal pain, muscle aches, and dizziness. Approximately 6% of persons receiving booster vaccinations with HDCV may experience an immune complex-like reaction characterized by urticaria, pruritis, and malaise. Once initiated, rabies postexposure prophylaxis should not be interrupted or discontinued because of local or mild systemic reactions to rabies vaccine.
The immune globulin is from humans, not horses like some immune globulin, so there is much less risk of a reaction ("serum sickness" -- bad rash and other things) from that.
Other facts about rabies:
All warm-blooded animals can get rabies; in the U.S. the most common animals are dogs, cats, cattle, skunks, raccoons, and bats.
You get infected with rabies usually by getting bitten by an infected animal, but inhalation of bat feces in bat caves (spelunkers beware!!!) has also been reported.
The incubation period is usually 2 - 16 weeks (10 days to 1 year is possible), and depends on the strain of the virus, how bad the bite was, and the physical length the virus must travel from the bite site to the brain.
The symptoms are a very severe, sudden encephalitis. It starts out with malaise, anorexia (no appetite), headache, nausea, vomiting, sore throat, and fever. The person then has increasing nervousness, apprehension, hyperventilation (breathing fast), salivation, sweating, confusion, hallucination, tearing (as in eyes), and spasms of throat muscles upon swallowing -- "hydrophobia". If the person has hydrophobia you pretty much know for sure that they have rabies. Eventually this progresses to convulsive seizures, coma, and death from respiratory paralysis. The person may have periods of brief hyperactivity, triggered by bright light, sound, or touch, with longer periods of quiet in between.
If a person develops these symptoms, pretty much 100% die within 3 to 5 days after the symptoms begin. My textbook says there are "extremely rare cases of survival."
30 to 50% of people with known exposure develop symptoms (I think this means people who didn't get the vaccine).
Diagnosis is made by seeing these things called "negri bodies" in nerves on a microscopic examination of a brain or corneal (eye) biopsy. I don't know how often they actually do this to people, though -- maybe animals more often.
Food poisoning (a.k.a. stomach flu, acute gastroenteritis)
Run-of-the mill food poisoning is usually caused by a toxin produced by a bacteria called Staph aureus, or by bacterial contamination of the food by Salmonella (or other bacteria). That's the kind that usually ends up in the picnic potato salad or anything with uncooked meat or poultry or raw eggs (including mayonaisse).
The toxin kind of food poisoning comes on very quickly, within an hour of eating the food. Symptoms include bad vomiting and diarrhea, with stomach cramps coming on later. Vomiting is more prominent than the diarrhea. The symptoms usually last around 24 hours, then the person gets better.
Salmonella food poisoning takes longer to come on -- it can be hours or up to several days later. The symptoms are similar -- stomach cramps, vomiting and diarrhea, with diarrhea often being worse. It also takes longer to get better -- it can be up to a week before the diarrhea resolves. You can also have a mild fever with it. If Salmonella is suspected, an antibiotic such as Ciprofloxacin can be given to cure the infection.
The most important thing with acute gastroenteritis (the medical term for food poisoning) is to keep from getting dehydrated. People should drink lots of fluids -- electrolyte solutions like Gatorade work well. If vomiting is a bad problem, they should avoid eating (usually they don't feel like eating anyway) and drink small sips of liquid, which tend to stay down better. When their stomach feels a little better (usually the next day), bland foods should be tried in small amounts (chicken soup, rice, crackers, cereal) without forcing themselves to eat if they don't feel like it. Fatty foods, high-protein foods (hamburger and french fries), and high fiber foods should be avoided initially because they are harder to digest. If the person cannot hold anything down and gets very dehydrated, they might have to go to the ER and get IV fluids to get rehydrated. An antiemetic (vomiting medicine) such as Phenergan or Compazine can be given as a suppository or through an IV (they come in pill form too but if you're vomiting it doesn't stay down too well). If diarrhea is the main problem, Kaopectate, Imodium, or Pepto-Bismol can work well. In general, if the diarrhea isn't causing bad dehydration, though, it may be better for the person to wait it out, since it is thought that giving anti-diarrheal medicines may slow the process of getting the bugs/toxin out of the body.
In severe acute gastroenteritis, a person can develop severe electrolyte disturbances from severe vomiting and diarrhea. In that case, they would have to be admitted to the hospital for correction of these electrolyte abnormalities. But most people don't usually get sick enough to need to stay in the hospital.
Does size have any affect on the severity? It can, especially in children who don't have the reserves of an adult and can get dehydrated very quickly. However, for most adults, size isn't a big factor in the severity of food poisoning.
The symptoms of dehydration may develop from too much vomiting or diarrhea and consist of thirst, dry mouth and skin, and feeling dizzy when getting up from a lying down position. Decreased urine output is another sign, as is a faster pulse rate. In severe dehydration the person can have a decline in mental alertness. The time it takes to get dehydrated all depends on how badly the person is vomiting/having diarrhea. The worse the vomiting/diarrhea and the less they are able to drink, the quicker they will get dehydrated. In the most severe cases, dehydration can develop over a few hours.
BTW, diarrhea caused by E.coli can be life-threatening, but only a specific type of E coli (causes renal failure, coma, bleeding problems, etc.). Most E coli diarrhea is simply what causes typical traveler's diarrhea. It's similar to Salmonella diarrhea I described above.
Pneumonia is an infection of the lungs. There are several different types of pneumonia, and it can be caused by viruses or bacteria. The nastiest kinds of pneumonia are caused by bacteria.
I'll describe community-acquired pneumonia, meaning the person wasn't in a hospital when they got sick. Hospital-acquired pneumonia is caused by different bugs and is treated with different antibiotics.
Classic community-acquired bacterial pneumonia is often caused by Streptococcus pneumoniae, Hemophilus influenzae, Staphylococcus, or anaerobic bacteria. Strep is probably the most common. The classic symptoms are high fever, chills, productive cough, difficulty breathing, and looking very sick. If you do a chest x-ray, you'll see a big white patch in the lungs where they have the pneumonia, and if you measure an oxygen saturation it may be low, and they may be breathing very fast. People with pneumonia do not necesasrily have to be hospitalized, if they don't look too bad and they have someone to take care of them and bring them back to the hospital if they get worse. Someone who should be hospitalized is a person who doesn't have someone to take care of them, who you don't think will come back if they get worse, or if their oxygen levels are too low (< 90% on room air), and they are having a lot of trouble breathing (breathing more than 30 times per minute) and look very sick, or if you tried to give them pills as an outpatient and they didn't get better. People who get the worst pneumonias are people with underlying lung disease (emphysema, cystic fibrosis, or other lung problems) or other medical problems and should also probably be admitted to the hospital. If it's a young, healthy person, they usually don't get really bad pneumonias. If they do, they usually recover with antibiotics.
The treatment for a classical bacterial pneumonia is antibiotics. For outpatient treatment, there are a lot of different oral antibiotics you can use. Erythromycin is the old standby, but the newer drugs Azithromax and Biaxin are very good (some doctors say better). The person should take the pills for at least a week, maybe 2, and be instructed to come back if they don't feel better in 2 or 3 days. If they get much worse (cannot breathe), they should go immediately to the E.R. for evaluation. Sometimes people with pneumonia have an element of airway constriction (bronchospasm), so they will benefit from inhaled medications such as albuterol.
If they don't get better and end up being admitted to the hospital, IV antibiotics are used: IV erythromycin plus an IV cephalosporin (usually cefotaxime or ceftriaxone). If the person is coughing up junk, the doctor may get a blood culture or sputum culture to see if they can figure out exactly which bugs are causing the pneumonia and which drugs the bacteria are sensitive to. The person should keep getting the antibiotic for several days *after* the fever stops (5 days to 2 weeks usually).
Not all community-acquired pneumonia is "classic." The other type is called "atypical community-acquired pneumonia" and is caused by different kinds of bacteria (namely Mycoplasma or Chlamydia), or a virus. This kind isn't as bad and is often referred to as "walking pneumonia." The person isn't incapacitated or bed-ridden, but they feel sick. The fever is milder, and the cough is often a dry hacking cough instead of a wet cough. The chest x-ray shows scattered white patches instead of one big one. These people rarely have to be admitted to the hospital. Erythromycin, Azithromax, or Biaxin work fine for Mycoplasma and Chlamydia (which is why you give these drugs to someone with pneumonia, because they cover classic and atypical pneumonia). If it's a virus, then no antibiotic will help and you just have to wait it out. Since there's no easy way to tell if it is a virus or bacteria, most doctors will treat with antibiotics anyway.
How do you get pneumonia? Well, it all comes down to your resistance (immune system) not being strong enough to counteract the bugs. Stress, other illness, and poor nutrition can all do it. Many old people develop pneumonia after they've had the flu because their resistance is down. You also have to get exposed to the bug somehow, so being around other people who are sick doesn't help. Can a bronchitis develop into a pneumonia? Well, yes, in a sense. For one thing, your resistance will be down and make you more vulnerable. Also, I think the bugs could theoretically travel deeper into the lungs and set up an infection. Normally they can't do that, but some viruses inactivate the cilia which sweep the junk out of the lungs, and that way the bugs can sneak by. Many patients give a history of having a regular "cold" that they never fully recovered from and it eventually "settled in their lungs."
Time to recover depends on how healthy the person is in the first place, but with antibiotics, 5 days to 2 weeks. It is common to have a residual dry cough after recovering. This may be a mild form of asthma that persists due to the respiratory lining being irritated by the past infection.
Antibiotic-resistant Organisms
Two common antibiotic resistant bacteria are MRSA (Methicillin Resistant Staphylococcus aureus) and VRE (Vancomycin Resistant Enterococcus). These infections are scary because there are often very few antibiotics which will cure the patient of the infection. Patients carrying these organisms (even if they aren't actively "septic" with an infection -- they only need to have a history of such an infection) are put under strict isolation because both MRSA and VRE are often resistant to multiple antibiotics and difficult to treat. Hospitals obviously don't want these patients infecting other patients. Doctors will order tests to find out exactly what antibiotics an organisms is sensitive to (what antibiotic will kill the bug). The test is called "Culture and Sensitivity" or "C & S". MRSA is usually treated with the powerful drug Vancomycin. There is no reliable antibiotic for VRE; a new drug called Synercid has been used, along with 3 drug combinations. In both cases, particularly when a patient is very sick, an infectious disease specialist should be consulted for advice on how to proceed.
Multi-drug resistant tuberculosis (TB) is also becoming a huge menace, especially in urban areas with lots of foreign immigrants and drug users, since they often carry multi-drug resistant TB. People infected with drug resistant TB must often be on 4 to 5 medications at a time for months to years in order to erradicate the infection. Noncompliance with medications (not taking them) is often the cause of multi-drug resistant TB and a major reason why it is so difficult to cure.