Varicella, also known as chickenpox, is a highly contagious illness caused by the varicella-zoster virus (VZV), a member of the herpesvirus family. It causes an itchy skin rash with red spots and small fluid-filled blisters that eventually dry out and form scabs. The rash usually starts on the face, chest, and back before spreading to … Read more
Ebola virus disease (EVD) is a serious and often deadly illness caused by viruses in the Ebolavirus group, which are part of the Filoviridae family. The virus is zoonotic, meaning it can spread from animals to humans. Fruit bats, particularly those in the Pteropodidae family, are believed to be the natural hosts of the virus. … Read more
Listeriosis is a foodborne illness caused by the bacterium Listeria monocytogenes. This microorganism is widespread in the environment and can be found in soil, water, and animal feces. It can survive and grow under conditions that inhibit many other bacteria, including refrigeration temperatures. The infection is most dangerous for pregnant women, newborn babies, older adults, … Read more
Lassa fever is a serious illness caused by the Lassa virus. People usually get infected through contact with the urine, feces, saliva, or nesting materials of infected multimammate rats (Mastomys natalensis), which often live in or around homes in West Africa. These rats are the natural carriers of the virus. The disease is common in … Read more
Brucellosis is a zoonotic bacterial infection caused by Brucella species—gram-negative, facultative intracellular pathogens that primarily affect livestock, including cattle (Brucella abortus), sheep and goats (Brucella melitensis), pigs (Brucella suis), and, less commonly, dogs (Brucella canis). These bacteria are highly infectious and can survive within host cells, evading the immune system and complicating treatment. The disease … Read more
Tularemia, also known as rabbit fever or deer fly fever, is a rare but potentially serious infectious disease caused by the bacterium Francisella tularensis. This bacterium is highly infectious, meaning that even a small number of organisms can cause illness. It is considered a zoonotic disease, which means it can be transmitted from animals to … Read more
Psittacosis — also known as parrot fever or ornithosis — is a zoonotic infectious disease caused by the bacterium Chlamydia psittaci. It is primarily transmitted to humans through inhalation of aerosolized secretions, droppings, or feather dust from infected birds, particularly parrots, pigeons, and poultry. The disease predominantly affects the respiratory system, with common symptoms including … Read more
Leprosy, also known as Hansen’s disease, is a chronic infectious disease caused by the slow-growing bacterium Mycobacterium leprae. It primarily affects the skin, peripheral nerves, mucous membranes, and eyes, leading to symptoms such as hypopigmented or reddish skin lesions, numbness, muscle weakness, and nerve damage. In advanced cases, untreated leprosy can result in deformities of … Read more
Botulism is a rare but potentially life-threatening paralytic illness caused by botulinum toxin, a neurotoxin produced by Clostridium botulinum and related species. The toxin interferes with normal nerve function by inhibiting the release of acetylcholine, leading to muscle weakness that can progress to respiratory failure if untreated. The disease occurs in several distinct forms, including … Read more
Yersinia pestis is a type of bacteria that causes plague, a serious and highly contagious disease that spreads from animals to humans. It belongs to a group of bacteria called Enterobacteriaceae and has a short, rod-like shape. This bacterium has been responsible for several major pandemics in history, including the Justinian Plague in the 6th … Read more