Infectious diseases are caused by pathogens, such as bacteria, viruses, fungi, and parasites, which can be transmitted from one person to another through direct contact, indirect contact, or vector-borne transmission. Genetic inheritance is not a mode of transmission of infectious diseases.

Direct contact transmission occurs when an infected person coughs or sneezes, releasing respiratory droplets that contain the pathogen into the air. These droplets can be inhaled by a nearby person, who can then become infected.

Indirect contact transmission occurs when a person touches an object or surface that has been contaminated with the pathogen and then touches their mouth, nose, or eyes. This can lead to infection if the pathogen is able to enter the body through these openings.

Vector-borne transmission occurs when a pathogen is transmitted from one person to another by an arthropod, such as a mosquito, tick, or flea. Malaria is an example of a vector-borne disease, as it is transmitted by mosquitoes.

Sexually transmitted infections (STIs) are infections that are spread through sexual contact. HIV/AIDS, hepatitis B, and syphilis are all examples of STIs.

Fever, cough, and diarrhea are all common symptoms of infectious diseases. These symptoms can be caused by a variety of pathogens, including bacteria, viruses, and parasites.

Antibiotics, antivirals, and antifungals are all types of medications that are used to treat infectious diseases. Antibiotics are used to treat bacterial infections, antivirals are used to treat viral infections, and antifungals are used to treat fungal infections.

Vaccination, handwashing, and safe sex are all preventive measures for infectious diseases. Vaccination can protect against specific infections, handwashing can help to prevent the spread of germs, and safe sex can help to prevent the transmission of STIs.

Surveillance, contact tracing, and quarantine are all public health measures that are used to control infectious diseases. Surveillance involves monitoring the occurrence of diseases in a population, contact tracing involves identifying and monitoring people who have been in contact with an infected person, and quarantine involves isolating infected people from the rest of the population.

Antimicrobial resistance, emerging infectious diseases, and re-emerging infectious diseases are all global health challenges related to infectious diseases. Antimicrobial resistance occurs when pathogens become resistant to the drugs that are used to treat them, emerging infectious diseases are new diseases that are spreading to new populations, and re-emerging infectious diseases are diseases that have been controlled in the past but are now making a comeback.

COVID-19, Ebola, and Zika are all examples of emerging infectious diseases. These diseases have all recently emerged and have caused significant public health concern.

Tuberculosis, measles, and cholera are all examples of re-emerging infectious diseases. These diseases were once controlled but have now made a comeback due to factors such as antimicrobial resistance and changes in public health practices.

Poverty, lack of access to healthcare, and poor sanitation are all social determinants of infectious diseases. These factors can increase a person's risk of exposure to pathogens and make it more difficult for them to get the treatment they need.

Beliefs about illness and disease, practices related to hygiene and sanitation, and social norms and behaviors can all influence the spread of infectious diseases. For example, beliefs about the causes of illness can affect people's willingness to seek medical care, and practices related to hygiene and sanitation can affect the risk of exposure to pathogens.

Sociologists can play a variety of roles in addressing infectious diseases. They can study the social and cultural factors that influence the spread of infectious diseases, develop interventions to prevent and control infectious diseases, and advocate for policies that promote health equity.