Infectious diseases are caused by pathogenic organisms such as bacteria, viruses, parasites or fungi. Many organisms live in and on our bodies. They are normally harmless or even helpful. But under specific conditions, some organisms may cause disease.
Infectious diseases can be spread through direct contact such as: Person to person, Animal to person, Mother to unborn child.
Disease-causing organisms also can be passed by indirect contact such as Insect bites, Food contamination. Some of the infectious diseases include typhoid, malaria, diarrhoea, fatigue, coughing, HIV/AIDS, pulmonary infectious diseases, hepatitis, dengue, tuberculosis, STDs/STIs, sepsis, neuro infectious diseases, pandemic & epidemic diseases.
A vaccine is a biological preparation that provides active acquired immunity to several diseases. Vaccines help the body immune system to fight against pathogens like viruses or bacteria, which keeps us safe from the life-threatening diseases including influenza, tetanus, diphtheria, measles, cervical cancer, meningitis, polio, tetanus and typhoid.
Some of the vaccines include HPV vaccines, DNA vaccines, Chickenpox (varicella) vaccine, diphtheria, Tetanus and Pertussis vaccines (DTaP), Influenza vaccine, measles, Mumps and Rubella vaccines (MMR).
An antibiotic is a kind of antimicrobial substance active against bacteria. Antibiotics, also known as antibacterials, are medications that prevent or slow down the growth of bacteria.
Antibiotics do not work for viral infections. There are some antiviral medicines to treat viral infections.
Antibiotics cause the following side effects rashes, diarrhea, nausea, vomiting, upset stomach, fungal infections of the mouth and digestive tract.
Clinical Immunology is associated with the study of diseases which are caused due to disorders of immune system i.e., abnormal growth of any cellular tissues of the system, hypersensitivities such as asthma, immune system failure and other allergies. Some of the immune diseases include autoimmune disease, hypersensitivity, immune disorder and immunodeficiency.
An allergic disease occurs when a person immune system reacts to substances present in the environment that are harmless for most people. These substances are known as allergens and are found in dust mites, pets, pollen, insects, ticks, moulds, foods and some medications. Some of the allergies include drug allergy, food allergy, insect allergy, latex allergy, mold allergy, pet allergy and pollen allergy.
Epidemiology is the study and analysis of the distribution, pattern and determinant of health and disease conditions in defined populations. Some of the diseases include cardiovascular disease epidemiology, cancer epidemiology, cognitive epidemiology, dental/oral epidemiology, epidemiology of aging, infectious disease epidemiology, injury epidemiology, intestinal epidemiology, neuroepidemiology, obesity/diabetes epidemiology, pediatric epidemiology, psychiatric epidemiology, renal epidemiology, reproductive epidemiology, respiratory epidemiology and veterinary epidemiology.
Emerging infectious diseases are infections that have recently appeared within a population those include new infections, previously unrecognized infections and old infections reappearing due to antimicrobial resistance, public health issues and unhygienic conditions. Some of the emerging infectious diseases include ebola hemorrhagic fever (Ebola virus disease), middle east respiratory syndrome (MERS), chikungunya virus, dengue fever, H1N1 influenza virus (swine flu), avian influenza (bird flu), nipah virus and zika virus.
Fungal diseases are usually caused by fungi that are common in the environment. Most fungi are not dangerous, but some types can be injurious to health. Some of the fungal infectious diseases include tinea corporis or ringworm, fungal nail infection, candida infections of the mouth, throat and esophagus.
Hepatitis is an inflammation of the liver tissue. Hepatitis is most commonly caused by the virus hepatitis A, B, C, D, and E.
Hepatitis A & E are mainly spread by contaminated water and food
Hepatitis B is mainly caused by sexual transmission, but may also be passed from mother to baby during pregnancy or childbirth and spread through infected blood.
Hepatitis C is frequently spread through infected blood such as needle sharing by intravenous drug users.
Hepatitis D can only infect the people that are already infected with hepatitis B.
HIV (human immunodeficiency virus) is a virus that attacks cells, making a person more vulnerable to other infections and diseases.
AIDS (acquired immunodeficiency syndrome) is the late stage of HIV infection that occurs when the body’s immune system is badly damaged because of the virus.
Some of the diseases include cervical cancer, vulvar cancer & genital warts (condyloma), penile cancer, anal cancer, human papillomavirus (HPV), hepatitis B (Hepatitis B virus) and herpes simplex (HSV1/HSV2).
Neglected tropical diseases (NTDs) are diverse group of communicable diseases that prevail in tropical and subtropical conditions.
The study of parasites, their hosts and the relationship between them is called Parasitology. A parasitic disease or parasitosis, is an infectious disease caused or transmitted by a parasite. Some of the parasitic diseases include amoebiasis, ascariasis, hookworm infection, avian malaria, abdominal angiostrongyliasis, chagas disease and babesiosis.
Children are more influenced to environmental risks than adults because of a number of reasons. Children are constantly growing so they eat more food, drink more water, and breathe more air as compared to adults. They have increased vulnerability to illness. Some of pediatric infectious diseases include lyme disease, persistent fever or fever of unknown origin, osteomyelitis (infection of the bone), complicated pneumonias, tuberculosis, lymphadenopathy (inflammation of the lymph nodes), recurrent infections those are mostly caused by bacteria, viruses, fungi and parasites.
Sexually transmitted diseases/ sexually transmitted infections are the infectious diseases which are transmitted through sexual contact, caused by bacteria, viruses or parasites. They are also known as venereal diseases (VD). Some of these diseases include HPV, HIV/AIDS, chlamydia, genital herpes, genital warts, gonorrhea, some forms of hepatitis, syphilis and trichomoniasis.
Tuberculosis (TB) is an infectious disease generally caused by Mycobacterium tuberculosis (MTB) bacteria. Tuberculosis mainly affects the lungs, but can also affect other parts of the body. Malaria is a mosquito borne infectious disease which influence humans and other animals. Malaria is caused by parasitic protozoans (a group of single cell microorganisms) belonging to the plasmodium type. Some of tuberculosis infectious diseases include active TB disease, miliary TB and latent TB infection.
A viral infection is a rapid growth of a harmful virus inside the body. Some of the viral diseases include smallpox, cold and different types of flu, measles, mumps, rubella, chicken pox, shingles, hepatitis, herpes, cold sores, polio, rabies, ebola and hanta fever, HIV, dengue fever, zika, epstein-barr virus (EBV) and human papilloma virus (HPV).
Zoonoses (also known as zoonosis and as zoonotic diseases) are infectious diseases caused by bacteria, viruses and parasites that spread between animals (usually vertebrates) and humans. Some of the zoonotic diseases include rabies, arbovirus infections, yellow fever, Q-fever, myiasis, anthrax, bird flu, zika fever and ebola virus disease.