Share This Link

Contaminated birth control devices: Modern birth control manufacturing and clinical insertion (like IUDs) follow strict sterile protocols; this is not a primary driver of high transmission rates.

Ineffective treatment options: Most common STIs have highly effective antibiotic or antiviral treatments available if diagnosed.

Contaminated catheters: While catheters can cause Urinary Tract Infections (UTIs), they are not a vector for the transmission of sexually transmitted infections.

Recognize pathogens: While they do have receptors (like TLRs) to recognize broad patterns, "recognition" in a specific immunological sense is more often associated with lymphocytes.

Produce antibodies: This is the exclusive function of B-lymphocytes (specifically plasma cells), not phagocytes.

All of the above: Incorrect because phagocytes do not produce antibodies.

Bacteroides fragilis: While a common part of the normal gut flora, it is more often associated with intra-abdominal abscesses rather than hospital-acquired colitis.

Clostridium perfringens: More commonly known for causing food poisoning and gas gangrene, rather than chronic hospital-associated colitis.

Staphylococcus aureus: While it can cause various infections, it is not the primary culprit for hospital-associated colitis.

Transient flora: These are organisms that land on the skin temporarily; they are usually the ones being competed against and do not provide a stable defense.

Pathogens: These are disease-causing organisms and are the threat that the defense system is trying to keep out.

All of the above: Incorrect because pathogens and transient flora do not serve a protective function.

Hydrogen Peroxide: While used as a disinfectant and antiseptic, it is not typically the standard for preserving tissues in a clinical/vaccine context compared to aldehydes.

UV radiation: UV is used for air and surface disinfection but cannot penetrate surgical instruments deeply and is not used to preserve tissues.

Isopropyl alcohol: Alcohol is an intermediate-level disinfectant; it cannot kill spores and is therefore not used for sterilization of surgical instruments.

An agent that kills bacteria: This specifically describes a bactericide. While sterilization does kill bacteria, the term "sterilization" is much broader and includes all life forms, including viruses and highly resistant bacterial spores.

An agent that kills fungi: This is the definition of a fungicide. Sterilization is not limited to one type of organism.

An agent that inhibits fungi growth: This describes a fungistatic agent. Sterilization involves total destruction, not just the inhibition of growth.

Bactericidal: The suffix "-cidal" means "to kill." A bactericidal agent kills bacteria outright rather than just inhibiting their growth.

Viricidal: This refers to an agent that kills or inactivates viruses, not one that inhibits bacteria.

Fungistatic: This refers to the inhibition of fungal growth, not bacterial growth.

Direct contact: Direct contact transmission requires physical touch between the infected source (the host) and the susceptible person (e.g., shaking hands or kissing).

Droplet: Droplet transmission involves large respiratory particles expelled through coughing, sneezing, or talking that travel short distances (usually less than 3 feet).

Biological vector: In biological transmission, the pathogen must complete part of its life cycle within the vector (e.g., a mosquito carrying malaria) before being transmitted through a bite or fluid exchange.

IgE: IgE is primarily involved in allergic reactions and defense against parasitic worms; it does not cross the placental barrier.

IgM: IgM is the first antibody produced during an initial infection. Because of its large pentameric structure, it is too bulky to cross the placenta.

IgA: IgA is found in secretions like saliva, tears, and breast milk (colostrum), providing neonatal immunity after birth, but it does not cross the placenta.

Impetigo: Impetigo is a skin infection (caused by Strep or Staph) that enters through the skin/parenteral route via cuts or abrasions.

Influenza: The influenza virus primarily uses the respiratory tract as its portal of entry via inhaled droplets.

Syphilis: Syphilis (Treponema pallidum) is a sexually transmitted infection that enters through the mucous membranes of the genitourinary tract.