Infectious Diseases

Communicable diseases are infections that are contagious and spread from person-to-person. Communicable diseases can cause epidemics and pandemics.

Some communicable diseases are nationally notifiable diseases that must be reported to the CDC (eg. Measles, Polio, Tuberculosis). Others, such as confirmed Influenza, Strep Throat (Streptococcal infections), are reported to local health departments. There are also common viral and bacterial infections such as the "Common Cold" (Rhinoviruses and various Coronaviruses), and Chickenpox (Varicella), that are common, especially in children and congregate living settings. Many communicable diseases have been eradicated or controlled through vaccinations and antibiotics.

Zoonotic diseases are infections in animals that are spread to humans. Usually this is through a "vector" (blood-feeding insect such as mosquitos and ticks) that can be transmitted to humans through a bite from an infected insect. Zoonotic diseases can also spread through direct contact with an infected animal (bats, rodents, and other mammals).

• West Nile Virus
• Malaria
• Rabies
• Lyme Disease

Food and water-borne diseases are often referred to as "food poisoning", as they tend to cause acute gastrointestinal (Gastroenteritis) symptoms shortly after consuming the food/water, but they are actually contaminated food, water, or sanitation that infects people. Most food/water-borne illnesses are bacterial or fungal, but can also be viral or parasitic; they are not poisons.

• Norovirus
• Salmonellosis (Salmonella)
• Escherichia coli (E.coli)
• Listeria (Listeria monocytogenes)

Historically, water-borne illnesses such as Cholera (Vibrio cholerae) and Typhoid Fever (Salmonella typhi) created huge outbreaks and epidemics, due to poor sanitation, but now are only found in the developing world.

Healthcare-associated infections (HAI) are infections that patients develop while in the hospital. Most HAI's are due to infections within invasive medical devices (catheters, ventilators), or at surgical sites. HAI's are also called "nosocomial infections"."

• CLABSI (central line-associated blood stream infections)
• CAUTI (catheter-associated urinary tract infections)
• VAP (ventilator-associated pneumonia)
• SSI (surgical site infections)

There are also antimicrobial-resistant infections, which are common bacterial or fungal infections that have developed resistance to treatments. Many antibiotic-resistant infections are acquired in the hospital. Today, there are six antibiotic-resistant bacterial threats:

• Carbapenem-resistant Enterobacteriaceae (CRE)
• Methicillin-resistant Staphylococcus aureus (MRSA)
• ESBL-producing Enterobacteriaceae (extended-spectrum β-lactamases)
• Vancomycin-resistant Enterococcus (VRE)
• Multidrug-resistant Pseudomonas aeruginosa (MDR-P)
• Multidrug-resistant Acinetobacter (MDR-A)