Introduction:
Hepatitis A virus (formerly known as Enterovirus 72) has a long history and it still has a big impact on human populations in the modern world. From time of the ancient Greek doctor Hippocrates, Hepatitis A virus (HAV) was noted for causing jaundice. By the 8th century, it was realized that icteric disease was caused by an infectious agent. Later in the history, in 1885, it was discovered by scientists that hepatitis could be spread through blood transfusions. Now, it is well- known that the virus is mainly transmitted via fecal-oral route which results from contamination of food and water by fecal matter and direct contact with infected individuals. Initially another icteric agent, Hepatitis B virus, was isolated in 1973 by Robert H. Purcell. This is followed by isolation of HAV from marmoset liver explant cultures in 1979(5). Understanding of HAV had started after WWII because of its massive impact on the soldiers and civilians under the contamination favored conditions of war. HAV was first visualized under electron microscope at the National Institutes of Health in the feces of volunteers who have had HAV infection (1, 2).
Hepatitis A virus causes acute viral hepatitis which is one of the most common infectious diseases that is resulted from inflammation of liver. HAV is not the only infectious agent that causes acute viral hepatitis. Several different viruses, named hepatitis A, B, C, D and E cause inflammation of liver. Different hepatitis viruses belong to different virus families. HAV is a small, 27 nm cubically symmetrical single stranded RNA virus with positive (+) strand polarity and is classified as a member of picorna virus family. It has also been classified as the main virus of hepatovirus genus...
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... hygiene may be more common. In the general population, seroprevalence rate of anti-HAV antibodies varies from 15% to 100% in different countries of the world. In developing countries, most infections occur by 5 years of age and seroprevalence rates can become as high as 100%(7). North Europe has the lowest seroprevalence rate in the world. Decreased seroprevalence is problematic as it is indicating that most of the individuals in the defined population are susceptible to HAV infection which can result in outbreak of an epidemic. In 1988, an epidemic occurred due to ingestion of inadequately cooked bivalve mollusks from sewage polluted water in Shanghai and resulted in infection of approximately 300,000 people(1). In regions where majority of individuals are susceptible to HAV infection, routine vaccination is suggested for prevention of HAV epidemic outbreaks(7).
This extremely pathogenic zoonotic virus is now understood to travel from bat species, to equine intermediate hosts, to humans.[8, 10] The Hendra virus is listed as a Bio-Safety Level (BSL)-4, and can only be studied at a few adequately equipped laboratories worldwide due to its virulence.[1, 2] Case fatality rates
The Hepatitis B virus is a disease that affects the liver and results in swelling and loss of normal function in the liver. It is estimated that 350 million people are infected with Hepatitis B worldwide, with 50 million new cases diagnosed every year.(1) In the Unit...
The Herpes virus is actually from a family of viruses that include 8 different virus strains that affect humans. The viruses are known through numbers 1 through 8 or HHV1-HHV8. HHV 1 and 2 are listed above while HHV 3, known as varicella zoster virus, and that causes chickenpox. HHV 3 can also cause a recurring skin infection known as herpes zoster or shingles. HHV 4 is known as the Epstein Barr virus, and is responsible for the easily spread mononucleosis, commonly referred to as “mono”. HHV 5 is known as...
Hepatitis B Virus (HBV) is a virus that leads to infection of the liver. Infection of the HBV can be acute or lifelong (chronic). Humans are the only known host for HBV (CSC, 2017). This virus can survive on environmental surfaces for up to seven days (WHO, 2017).
Changes in the way cases of valley fever are being detected and reported to public health officials, or
For example, those who travel to or live in countries where Hepatitis A is common, have sexual contact with someone who has Hepatitis A, men who have sexual encounters with other men, those who use recreation drugs, have clotting-factor disorders, or are household members or caregiver of someone who is infected with the virus. Other risk factors include intermediate and high endemicity areas include poor sanitation and regulations and lack of safe water. Also, residents from regions with low endemicity for the Hepatitis A Virus infection often remains susceptible in their adulthood. In areas where the virus is wide spread, most Hepatitis A infections occur during early childhood because children tend to ingest everything. As mentioned earlier, adults have signs and symptoms of illness more often than children. The severity of the disease and its fatal outcomes are higher in older age
Hepatitis is the inflammation or swelling of the liver. The inflammation can happen from different injuries or viral forms of a disease. People who experience hepatitis have the symptoms of malaise, nausea, vomiting, loss of appetite, fever and jaundice. There are six known forms of Hepatitis which are Hepatitis A, Hepatitis B, Hepatitis C, Hepatitis D, Hepatitis E and Hepatitis G. The presence of hepatitis in the body can be very risky and cause severe death if not taken care of. Hepatitis is a severe issue that affect many people around the world like third world countries and cross contamination can occur mainly in health care places due to the exposure of patients with the disease and accidents handling blood or instruments, Hepatitis A,B,C,D,E and G are distinct diseases that differ in transmission and vaccines to prevent them or cure them.
Hepatitis B is a DNA viral infection that causes damage and inflammation to the liver. It was first discovered in 1965 by Dr. Baruch Blumberg. The HBV virus is very contagious and is even thought to be the most serious form of viral hepatitis and the most common viral infection on Earth. “HBV is 100 times more infectious than HIV.” (Green, 2002, pg. 7) The virus can survive for about one week outside the body on a dry surface. According to Green (2002, pg. 7), “One in twenty Americans has been infected with the virus at some point in their lives.” Between the ages of 15-39 is when 75% of new HBV infections occur, according to Green (2002, pg.8).
Pathogens are a type of microorganism that spreads viral and bacterial diseases. These diseases when present in human blood and body fluids are known as blood borne pathogens, and can spread from one person to another. (Worcester polytechnic institute) The most serious types of blood borne diseases are the hepatitis B virus (HBV) and hepatitis C virus (HCV), which can cause liver damage; and HIV (human immunodeficiency virus), which is responsible for causing AIDS (acquired immune deficiency syndrome). The blood borne pathogens can be spread when the blood or body fluids (semen, vaginal fluid, breast milk, and amniotic fluid) of an infected individual comes into contact with mucous membranes or an open sore or cut on the skin of another person. Mucus membranes are located in the eyes, nose, mouth, and other areas as well. ("Bloodborne pathogens: MedlinePlus Medical Encyclopedia") Two of the most common ways that pathogens are transmitted is through the exchange of fluids during sexual intercourse or by sharing infected IV needles. (Worcester polytechnic institute)
Hepatitis A is a usually short acting virus that occurs in humans and monkeys. It is caused by the Hepatovirus and the species is Hepatitis A Virus. There are two major ways in which Hepatitis A can be transmitted. One way is from person to person. This transmission occurs when the fecal matter of an infected person gets ingested by another person. Other ways Hepatitis A can be transmitted from person to person are through direct contact with an infected person, such as sexual contact, and sharing of needles for intravenous drug use. Hepatitis A can also be transmitted through coming in contact with contaminated food or water. Also foods that are uncooked or undercooked and have been contaminated with Hepatitis A can transmit the virus. (Bennett,
The incubation period for this virus is 10 to 50 days, depending on the amount of the contaminated source that was ingested. About 22,700 cases of Hepatitis A are reported annually. All people who ingest the virus are susceptible to illness, especially immune compromised individuals such as the elderly and children. Although, this virus is most common in adults. The individuals that ingested the contaminated product remain contagious 10 days following initial infection, most of the time prior to symptoms (1).
Recent research shows that, there are three major means by which infections can be transmitted and they include direct transmission, indirect transmission and airborne transmission (Hinman,Wasserheit and Kamb,1995). Direct transmission occurs when the physical contact between an infected person and s susceptible person takes place (division of public health, 2011). An example is a health care worker who attends to an Ebola patient, without gloves, gown and mask plus forget to wash his or her hand with soap and hot water and or a person having flu without the use of mask or washes his hand after sneezing easily passes the infection to the other through hand shake or surface touch, living the bacteria there for another vulnerable person to also touch if the surface is not disinfected with bleach. Studies makes it clear that, the spreads takes effect when disease-causing microorganisms pass from the infected person to the healthy person through direct physical contact such as touching of blood, body fluids, contact with oral secretion, bites kissing, contact with body lesions and even sexual contact. However, measles and chicken pox are said to be conditions spread by direct
Heymann, D. (2004). Control of Communicable Diseases Manual.18th edition. Washington, DC: American Public Health Association.
There is a disease spreading out in the world called Hepatitis C. It affects the liver and may cause the liver to fail. This disease is caused by a virus called Hepatitis C virus which is also known as HCV. About 32,000 people are affected with this disease per year only in the United States area. Some It’s a disease with many symptoms and many causes. of these symptoms are easy bruising, upset stomach and fever. These are just some of the many symptoms that come from the virus. Hepatitis Cs nature of the causative agent is determined by many things. The biological data of this disease is filled so much information. It is estimated that over 180 million people have gotten Hepatitis C and it is growing.
Viruses can be transmitted in many ways. Being in contact with an infected person will most likely transfer the virus. One can also obtain the virus through swallowing, inhaling, and unsafe sex. Poor hygiene and eating habits usually increase the risk of catching a viral infection. Contracting a viral infection is followed by adverse s...