According to the CDC, the most common pathogens that cause nosocomial infections are Staphylococcus aureus, Pseudomonas aeruginosa, and E. coli. Some of the common nosocomial infections are urinary tract infections, respiratory pneumonia, surgical site wound infections, bacteremia, gastrointestinal and skin infections.

Nosocomial infections also referred to as healthcare-associated infections (HAI), are infection(s) acquired during the process of receiving health care that was not present during the time of admission.

However, Koch’s postulates have their limitations and so may not always be the last word. They may not hold if: The particular bacteria (such as the one that causes leprosy) cannot be “grown in pure culture” in the laboratory. There is no animal model of infection with that particular bacteria.

A nosocomial infection (HAI) is one that: a patient develops during hospitalization or erupts within 14 days of hospital discharge. An example of a fomite would be: a drinking glass used by a patient, bandages from an infected wound, soiled bed linens.

Box 2: Practical methods for preventing nosocomial infection

1. Hand washing: as often as possible. use of alcoholic hand spray.
2. Stethoscope: cleaning with an alcohol swab at least daily.
3. Gloves: supplement rather than replace hand washing.
4. Intravenous catheter: thorough disinfection of skin before insertion.

Opportunistic, drug-resistant gram-negative bacteria are the most frequent causes of nosocomial infections. 5. Patients with burns, surgical wounds, and suppressed immune systems are the most susceptible to nosocomial infections.

Nosocomial infections are those which are acquired by the patient within 48-72 h or 3 days of admission in the hospital or medical care unit. The microbes cause nosocomial infections originated in hospitals, clinics, and medical care center.

Among this population, children with known immunocompromise at baseline are at greatest risk for acquiring nosocomial infection related in part to their inability to fight infection; however, this group of children accounts for at most 10 % of the population in the pediatric intensive care unit.

Certain underlying diseases, procedures, hospital services, and categories of age, sex, race, and urgency of admission were all found to be significant risk factors for nosocomial infection.

All hospitalized patients are susceptible to contracting a nosocomial infection. Some patients are at greater risk than others-young children, the elderly, and persons with compromised immune systems are more likely to get an infection.

Hospital-acquired infections are caused by viral, bacterial, and fungal pathogens; the most common types are bloodstream infection (BSI), pneumonia (eg, ventilator-associated pneumonia [VAP]), urinary tract infection (UTI), and surgical site infection (SSI).

The most common types of HAIs are:

• urinary tract infections (UTIs)
• surgical site infections.
• gastroenteritis.
• meningitis.
• pneumonia.

The most common types of infection acquired in hospitals are:

• bloodstream infection.
• urinary tract infection (UTI)
• wound infection.
• pneumonia (lung infection).

The 6 points include: the infectious agent, reservoir, portal of exit, means of transmission, portal of entry, and susceptible host. The way to stop germs from spreading is by interrupting the chain at any link.

Break the chain by cleaning your hands frequently, staying up to date on your vaccines (including the flu shot), covering coughs and sneezes and staying home when sick, following the rules for standard and contact isolation, using personal protective equipment the right way, cleaning and disinfecting the environment.

Contact is the most frequent mode of transmission of health care associated infections and can be divided into: direct and indirect. An example of contact transmitted microorganisms is Noroviruses which are responsible for many gastrointestinal infections.

Two or more cases of diarrhoea and/or vomiting in a 24 hour period in an institution or among a group of people who shared a common exposure or food source should be suspected as constituting an outbreak and an assessment or investigation commenced.

The manager of the care home should inform the HPU if they suspect that there may be an outbreak of an infection or infectious disease – that is two or more residents present with the same symptoms of an infection.

An outbreak of infection can potentially have a devastating effect on both the individual that you care for and the organisation that you work for. An infection can be fatal to the individual if action is not taken swiftly and will also cause ill-health to varying degrees.

Section 2: Steps of an Outbreak Investigation

1. Prepare for field work.
2. Establish the existence of an outbreak.
3. Verify the diagnosis.
4. Construct a working case definition.
5. Find cases systematically and record information.
6. Perform descriptive epidemiology.
7. Develop hypotheses.
8. Evaluate hypotheses epidemiologically.

Outbreak investigations help us learn more about the causes of outbreaks. Officials can learn what germs are causing waterborne illness, what types of water are involved, and what groups of people become ill. This knowledge can be used to control an outbreak and prevent additional illnesses.

What are outbreak control measures?

1. Cleaning and disinfecting food facilities.
2. Temporarily closing a restaurant or processing plant.
3. Recalling food items.
4. Telling the public how to make the food safe (such as cooking to a certain temperature) or to avoid it completely.

Epidemic management activities include taking appropriate control measures, such as treating those who are ill to reduce the reservoir of infection, and providing health education to limit the transmission of the disease to others.

Which is likely the most serious problem associated with an epidemic? People often die from the diseases that spread. Why did most revolutions end by 1850?

COVID-19 is declared a pandemic because of the speed at which it has spread globally. The World Health Organization declares COVID-19 to be a controllable pandemic and continues to provide advice on precautionary practices and ways to stop the spread of the disease.