Question

Please answer all

2. Create a flowchart to represent each step in an infectious disease process.

3) List the patterns of transmission of communicable diseases.

4) Define healthcare-associated infection, listing the most common types, and the factors that influence the development of these infections

5) Explain the following terms associated with epidemiology:

Incidence

Endemic

Morbidity rate

Prevalence

Reportable disease

Mortality rate

Pandemic

Epidemic

Answer 1

2) Steps in infectious disease process

1. Exposure or transmission of an infectious agent - Transmission occurs when the infectious agent leaves the reservoir (or host) through a portal of exit, travels by some mode of transmission, and enters through a portal of entry to infect a susceptible host
2. Incubation period - It is the time required for the replication and the onset of symptomatic disease. The host immune response is triggered for the evasion of microbe from the host.
3. If the host immune response successfully evades the microbes then their will be no illness otherwise illness occurs that can lead to symptomatic transmission of the microbe
4. In the case of illness, the host can either develop carrier state where host do not shows any symptoms, can lead to asymptomatic transmission.

3) Transmission can occur by a mode that is direct or indirect -

• Direct mode - On coming in close contact with reservoir of infectious agent via saliva, blood, droplets (sneezing and coughing), vertical (from mother to the baby), vector (carrier of infectious agent) and bites from biological vector, injection or direct contact with contaminated blood products, intravenous/ intramuscular injections.
• Indirect mode - On coming in contact with the contaminated material or the used material by the infected host such as food, water, biological samples (blood,serum, tissue) and oral-fecal as well as from air (droplet nuclei and aerosols) and also from fomites

4) Nosocomial infections or healthcare associated infections (HAI) occur in patients under medical care. These infections can occur during healthcare delivery for other diseases and even after the discharge of the patients.

Common pathogens such as Staphylococcus aureus, Pseudomonas aeruginosa, and E. coli are the cause of nosocomial infections. Some of the common nosocomial infections are urinary tract infections, respiratory pneumonia, surgical site wound infections,bacteremia, gastrointestinal and skin infections