Hepatitis A outbreak associated with a Mothers' Day 'Yum Cha' meal, Sydney, 1997

Hepatitis is an inflammatory condition of the liver most commonly caused by hepatotropic viruses (A–E), though non-infectious causes such as alcohol and drugs also exist.Hepatitis AHepatitis A virus (HAV) is a non-enveloped RNA virus of the Picornaviridae family. It is primarily transmitted via the fecal-oral route, typically through ingestion of contaminated food or water. After ingestion, HAV enters the bloodstream through the oropharynx or intestinal epithelium and reaches the liver. The...

Multistate foodborne outbreaks pose significant public health risks and require meticulous investigation to identify sources and implement control measures. The Centers for Disease Control and Prevention (CDC) utilizes a dynamic seven-step process for these investigations, integrating data from laboratories, interviews, and environmental assessments to protect public health.Outbreak Detection: The detection of multistate outbreaks typically begins with PulseNet, the CDC's national laboratory...

Viral hepatitis is an inflammatory condition of the liver caused by infection with hepatotropic viruses, most commonly hepatitis A, B, C, D, and E. Despite variations in structure and transmission, all viruses mentioned infect hepatocytes and provoke immune responses that can hinder liver function. Additionally, some non-hepatotropic viruses can also lead to hepatic inflammation.Hepatitis A VirusHepatitis A virus (HAV) is transmitted through the fecal–oral route, typically by ingestion of food...

Yellow fever is a viral hemorrhagic disease caused by the yellow fever virus (YFV), a member of the Flaviviridae family. It is transmitted primarily by Aedes and Haemagogus mosquitoes in tropical and subtropical regions of Africa and South America. After transmission through a mosquito bite, the virus initially replicates in skin-resident immune cells such as dendritic cells and macrophages. These cells then migrate to the lymph nodes, where viral replication increases, eventually leading to...

Chickenpox is an acute, highly contagious disease caused by the varicella-zoster virus (VZV), a double-stranded DNA virus belonging to the Herpesviridae family. Its transmission occurs primarily through the inhalation of respiratory droplets or direct contact with vesicular fluid from skin lesions. The incubation period typically ranges from 10 to 21 days, during which the virus replicates and disseminates through sequential phases within the host. Although generally self-limiting in children,...

Cholecystitis is inflammation of the gallbladder, most commonly caused by obstruction of the cystic duct. This blockage prevents bile from draining, leading to gallbladder distension, inflammation, and potentially serious complications. This condition may present acutely or chronically and can happen with or without gallstones.EtiologyAbout 95% of cholecystitis cases are calculous, caused by gallstones blocking the cystic duct, leading to bile accumulation and inflammation of the gallbladder...