Communicable Disease and Public Health

Communicable diseases are contagious illnesses caused by infectious or pathogenic agents. As a public health nurse, you'll prevent and control communicable diseases.

Now, the ability of a communicable disease to spread and cause infection depends on the interaction between three main factors that form the epidemiological triangle.

These factors include an infectious agent which can be any disease causing microorganism, including bacteria, viruses, fungi or parasites, a host or any person or animal harboring the infectious agent and the environment which are the external factors that influence disease, transmission like sanitation, crowding or the presence of disease, transmitting insects like ticks.

The epidemiological triangle provides a foundation for understanding the sequence of events involved in the spread of infectious disease that are outlined in the chain of transmission.

The first link in the chain is an infectious agent which lives and multiplies in its reservoir. The reservoir can be another human and animal water food or contaminated surfaces.

The pathway by which the infectious agent leaves the reservoir is the portal of exit like bodily fluids or open wounds. After that, the mode of transmission is how the pathogen travels from the reservoir to a new host.

This can involve direct transmission such as through sexual intercourse, skin to skin contact or respiratory droplets or indirect transmission like touching a contaminated object such as a door handle.

Next. The infectious agent needs a portal of entry, which is the pathway by which it enters a new host, like through the mouth, nose, eyes, mucous membranes or breaks in the skin.

Lastly, the susceptible host is anyone at risk for infection due to factors like age health status and immunity. All right.

So, controlling communicable diseases is a key means of protecting and supporting public health control involves reducing the incidence or new cases and prevalence or existing cases of a communicable disease to a locally acceptable level and continued efforts are required to maintain the reduction.

For instance, the widespread use of vaccines can significantly control the number of new cases and deaths from vaccine preventable diseases like measles and rubella within a community.

On the other hand, elimination is when a disease is controlled in a specific geographical area like a country. So there are no new cases though continued efforts are needed to prevent reestablishment of transmission.

An example of this is when there are no new polio cases in a specific country using an ongoing vaccination campaign if the disease is permanently eliminated, meaning the worldwide incidence of a disease has been reduced to zero and control measures are no longer needed.

The disease has been eradicated, for instance, smallpox was eradicated in the 20th century with the virus. Now only existing within laboratories as the public health nurse, you'll prevent and control communicable diseases by breaking the chain of transmission.

So to improve the resistance of a potential host in the chain of transmission, you'll advocate the use of vaccines for communicable diseases that are vaccine preventable, such as COVID-19, rotavirus and varicella and ensure members of your community are up to date with their immunizations.

They'll also provide education to address vaccine hesitancy and explain immunization schedules especially for school age Children.

In addition, you'll identify any medical religious or personal exemptions to receiving a vaccine. And before administering a vaccine screen for contraindications such as allergies and monitor for adverse reactions afterwards, you also can control the pathogen in the chain of transmission for communicable diseases that are not vaccine preventable.

So for certain sexually transmitted infections or STIs s such as chlamydia syphilis and HIV, you'll identify those at risk for infection and provide education about how specific sexually transmitted infections are spread and how to minimize transmission, like using condoms and limiting the number of sexual partners.

For those who are at high risk for HIV infection, you can encourage them to discuss preexposure prophylaxis or prep with their healthcare provider.

Also, since infected individuals can act as human reservoirs, you can conduct early screenings so they can be treated which can help decrease transmission of a communicable disease to others.

In addition to encouraging routine screenings for ST S, you'll also provide information about signs and symptoms of sexually transmitted infections and when to seek care.

Other interventions you can employ to control transmission of communicable diseases include addressing the portals of exit and entry of infectious agents.

By implementing infection control measures. These measures include standard precautions which are broad protocols used for all individuals including hand hygiene and personal protective equipment like gloves, gowns, masks or face shields.

Also provide education on and implement transmission based precautions which are measures used along with standard precautions that are based on how a specific disease spreads.

These include contact droplet and airborne precautions. For instance, contact precautions are used for diseases that spread by direct or indirect contact like clostridioides, difficile and include gloves gown and dedicated or disposable equipment used in their care.

Droplet precautions are used for infections that spread through respiratory droplets as seen with influenza and include a mask and keeping the infected individual away from others.

And airborne precautions are used for infections that spread through airborne particles that suspend in the air like tuberculosis and includes using an N95 respirator mask or use of a negative airflow room.

When it comes to controlling non-human reservoirs or pathogens. You can increase public awareness about food safety measures like avoiding cross contamination between uncooked foods like raw meat and other foods, cleansing fruits and vegetables before preparing them cooking foods to an appropriate internal temperature to kill potential pathogens, checking expiration dates on prepared foods, properly, storing foods at the correct temperature and washing hands before preparing and eating foods.

Lastly, for any reportable communicable disease, be sure to file a report with the Public Health department and assist with contact tracing as needed.

All right, as a quick recap, communicable diseases are contagious illnesses caused by infectious or pathogenic agents such as bacteria, viruses, fungi or parasites.

As a public health nurse, you'll prevent and control communicable diseases by breaking the chain of transmission through education, providing vaccinations and using standard and transmission based precautions.