Antibiotics!

• Antibiotics are among the most frequently prescribed medications in modern medicine.

• Antibiotics cure disease by killing or injuring bacteria.

• The first antibiotic was penicillin, discovered accidentally from a mold culture. Today, over 100 different antibiotics are available to cure minor, as well as life-threatening infections.

• Although antibiotics are useful in a wide variety of infections, it is important to realize that antibiotics only treat bacterial infections. –Antibiotics are useless against viral

infections (for example, the common cold) and fungal infections (such as ringworm).

• Antibacterial antibiotics are commonly classified based on their mechanism of action, chemical structure, or spectrum of activity.

• Most target bacterial functions or growth processes.– Target the bacterial cell wall.– The cell membrane – Interfere with essential bacterial enzymes– Target protein synthesis

Resistance of bacteria• The emergence of resistance of bacteria to

antibacterial drugs is a common phenomenon. • Reflects evolution (natural selection). • Basically, antibacterial treatment selects for

bacterial strains with enhanced capacity to survive high doses of antibacterials.

• Under certain conditions, it may result in preferential growth of resistant bacteria (ie, selecting the “most fit”)

• Resistance to antibacterials also occurs through horizontal gene transfer. This is when bacteria swap some DNA!

• Horizontal transfer is more likely to happen in locations of frequent antibiotic use, like a hospital!

• Many antibacterials have become less effective, because of increased resistance.

• Antibacterial-resistant strains and species, sometimes referred to as "superbugs", now contribute to the emergence of diseases that were for a while well controlled.

• For example, emergent bacterial strains causing tuberculosis (TB) that are resistant to previously effective antibacterial treatments pose many therapeutic challenges.

• Every year, nearly half a million new cases of multidrug-resistant tuberculosis (MDR-TB) are estimated to occur worldwide.[

Causes of the increase in resistance?• Inappropriate antibacterial treatment and overuse

of antibiotics have contributed to the emergence of antibacterial-resistant bacteria.

• Self prescription of antibacterials is an example of misuse.

• Many antibacterials are frequently prescribed to treat symptoms or diseases that do not respond to antibacterial therapy or are likely to resolve without treatment. One study on respiratory tract infections found "physicians were more likely to prescribe antibiotics to patients who appeared to expect them".

• Failure of medical professionals to prescribe the correct dosage of antibacterials on the basis of the patient's weight and history of prior use.

• Failure to take the entire prescribed course of the antibacterial.

• There has been extensive use of antibiotics in animal husbandry.

• The overuse of antibacterials, like penicillin and erythromycin, have been associated with emerging antibacterial resistance since the 1950s.

• Widespread usage of antibacterial drugs in hospitals has also been associated with increases in bacterial strains and species that no longer respond to treatment with the most common antibacterials

Reduce the resistance?• Take your entire course of antibiotics.– Even though you may feel better before your

medicine is entirely gone, follow through and take the entire course. – If an antibiotic is stopped in midcourse, the

bacteria may be partially treated and not completely killed, allowing for more resistant bacteria to survive.– This can cause a serious problem if those now-

resistant bacteria grow enough to cause a reinfection.

• Holiday Lecture on Bacterial resistance.

Vaccine Debate!

• The vaccine debate comes from misinformation/mistrust & vs. scientific data & testing.

• It is difficult to summarize the two sides but not impossible!

Anti-Vaccine• DON’T GET VACCINATED• CLAIMS:• Too many during childhood.• Just get the disease is fine.• Probably won’t get the disease because it’s so rare

now so why vaccinate?• Preservatives in the vaccines are toxic and placed

right into the blood steam, no way for your body to filter.

• Unvaccinated kids are healthier overall.• Side effects like seizure, autism, etc

Pro-Vaccine• GET VACCINATED• Claims:• Diseases that were “gone” come back b/c we do not

live in a bubble. What might not exist here probably does in other places thus get vaccinated

• Prevent diseases with side effects that cripple or kill• Vaccinate for the greater good- some people cannot

get vaccinated for medical reasons• No significant correlation between many side effects

claimed by anti-vaccine types and vaccine• Documented & correlated major side effects (seizure,

coma, etc) are extremely rare

• We will watch a PBS Frontline Video called “Vaccine War”.

• 1st we’ll take a survey.• During the movie please do your best to

answer the questions on the worksheet.