A contagious diseases are a subset category of transmissible diseases (can transmit from person to another), usually infections or some non-infection diseases, which are transmitted to other persons, either by physical contact (hence the name-origin) with the person suffering the disease, or by casual contact with their secretions or objects touched by them or airborne route among other routes.
Islamic point of view is that contagious diseases are spread with Allah Ta’ala’s Will only. As mentioned in Hadees no. 2 please read it below.
Contagious diseases can be spread mostly in 3 ways. 1) Direct physical contact with an infected person. 2) Direct physical contact with objects & other surfaces that an infected person has touched. 3) Coming in contact with airborne bacteria (through sneezing & coughing).
Quarantine is used to separate & restrict the movement of persons; it is a 'state of enforced isolation'. This is often used in connection to disease & illness, such as those who may possibly have been exposed to a communicable disease.
Communicable diseases spread from one person to another or from an animal to a person. The spread often happens via airborne viruses or bacteria, but also through blood or other bodily fluid. The terms infectious & contagious are also used to describe communicable disease.
What is the difference between infectious & contagious diseases?
Infectious diseases: are caused by microscopic germs (such as bacteria or viruses) that get into the body & cause problems. Some - but not all - infectious diseases spread directly from one person to another. Infectious diseases that spread from person to person are said to be contagious. Some infections spread to people from an animal or insect, but are not contagious from another human. Lyme disease is an example: You can't catch it from someone you're hanging out with or pass in the street. It comes from the bite of an infected tick.
Contagious diseases: (such as the flu, colds, or strep throat) spread from person to person in several ways. One way is through direct physical contact, like touching or kissing a person who has the infection. Another way is when an infectious microbe travels through the air after someone nearby sneezes or coughs.
Sometimes people get contagious diseases by touching or using something an infected person has touched or used - like sharing a straw with someone who has mono or stepping into the shower after someone who has athlete's foot. & sexually transmitted diseases (STDs) are spread through all types of sex - oral, anal, or vaginal. We can help protect yourself against contagious diseases by washing your hands well & often, staying away from those who are sick, making sure you're up to date on all vaccinations & always using condoms during any type of sex.
1. Narrated from a man from Al Ash-Sharid, who was called Amr that his father said: "Among the delegation of Thaqif there was a man who suffered from leprosy. Nabi ﷺ sent word to him saying: 'Go back, for I have accepted your pledge."
[Nasa’i: 4182; Book. 39; English vol. 5; Book. 39, Hadees. 4187]
2. Narrated by Abdullah Bin Umar رضي الله عنهما that Nabi ﷺ said: "There is neither A’dwa (لاَ عَدوٰی) (no contagious disease is conveyed to others without Allah's permission) nor Tiyara, but an evil omen may be in three, a woman, a house or an animal."
[Bukhari: 5753; Book. 76; English vol. 7; Book. 71; Hadees. 649]
3. Narrated by Abu Hurairah رضي الله عنه said that Nabi ﷺ said: (There is) no 'Adwa (no contagious disease is conveyed without Allah's permission) nor is there any bad omen (from birds), nor is there any Hamah, nor is there any bad omen in the month of Safar & one should run away from the leper (a person suffering from leprosy) as one runs away from a lion.
[Bukhari: 5707; Book. 76; English vol. 7; Book. 71; Hadees. 608]
The list below is of contagious diseases, they may range from highly contagious to only mildly. & the duration varies as well. As the name implies, sexually transmitted diseases, or STDS, are contagious. They are transmitted human to human via some type of sexual contact. List of these infectious diseases include: -
HPV, crabs, herpes, syphilis, virginitis, hepatitis, HIV/AIDS, chancroi, gonorrhea, chlamydia, trichomoniasis, non-gonococcal urethritis, pelvic inflammatory diseases. All respiratory diseases, athlete's foot, bronchitis, chickenpox, cold sores, common cold, conjunctivitis (pink eye), coxsackievirus, crabs-group-cryptosporidiosis, diphtheria, encephalitis, epstein-barr virus, fifth disease flu (Influenza), fungal skin infections, giardiasis, hepatitis B, impetigo.
Also infectious mononucleosis, leprosy, leptospirosis, lice, malaria, measles, meningitis, meningococcemia molluscum, contagiosum mononucleosis, mumps, nail fungus, pertussis (whooping cough), plantar warts, poliomyelitis (polio), ringworm, roseola infantum, scabies, scarlet fever, shigellosis, smallpox, staph infection (MRSA), strep throat-swine, flu, syphilis, tetanus, tonsillitis, tuberculosis, virginitis, viral gastroenteritis, viral laryngitis, skin diseases & etc.