Hepatitis E
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| Hepatitis E virus
Template:Taxobox begin placement virus Template:Taxobox group iv entry | |
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| Family: | Hepeviridae |
| Genus: | Hepevirus |
| Species: | Hepatitis E virus |
|} Hepatitis E is a hepatitis (acute disease, inflammation of liver) caused by a contagious virus called hepatitis E virus(acronym HEV).
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Signs and symptoms
It is most common in adults between the ages of 15 and 40. Though children often contract the disease as well, they rarely become symptomatic. Mortality rates are generally low, for Hepatitis E is a “self-limiting” disease, in that it usually goes away by itself and the patient recovers. However, during the duration of the infection (usually several weeks), the disease severely impairs a person’s ability to work, care for family members, and obtain food. Hepatitis E occasionally develops into an acute liver disease, and is fatal in about 2% of all cases. Clinically, it is comparable to hepatitis A, but in pregnant women the course can be fulminant. Pregnant women, especially those in the third trimester, generally suffer an elevated mortality rate from the disease.
Virology
The virus consists of a single strand of non-enveloped RNA, about 33 nanometers in length. It is sometimes classified in the Caliciviridae family. However, its genome more closely resembles the rubella virus one and this virus may in the future be reclassified.
Epidemiology
Patterns
Hepatitis E is prevalent in most developing countries, and not uncommon in any country with a hot climate. It is widespread in Southeast Asia, northern and central Africa, India, and Central America. It is spread mainly through fecal contamination of water supplies or food; person-to-person transmission is uncommon. Outbreaks of epidemic Hepatitis E most commonly occur after heavy rainfalls and monsoons because of their disruption of water supplies. Major outbreaks have occurred in New Delhi, India (30,000 cases in 1956-1957), Myanmar (20,000 cases in 1976-1977), Kashmir, India (52,000 cases in 1978), Kanpur, India (79,000 cases in 1991, and China (100,000 cases between 1986 and 1988).
Recent outbreaks
In 2004, there were two major outbreaks, both of them in sub-Saharan Africa. There was an outbreak in Chad in which, as of September 27 there were 1,442 reported cases and 46 deaths. In Sudan, which has been troubled with conflict recently (see, Darfur conflict), they are also suffering from a severe Hepatitis E epidemic. As of September 28, there were 6,861 cases and 87 deaths, mainly in the West Darfur Region. UNICEF, Doctors Without Borders, the Red Cross, and other international health organizations are currently working to increase the availability of soap, dig new wells, and chlorinate water supplies and reserves. However, the existing resources are still not enough, and more personnel and funds are severely needed in the region to assure the health and welfare of the people.
Prevention
Currently, the only viable method of prevention is improving sanitation, since no vaccine exists for the disease. Proper treatment and disposal of human waste, higher standards for public water supplies, improved personal hygiene procedures and sanitary food preparation are all important measures in preventing the spread of this disease. Thus, prevention strategies of this disease are similar to those of many others that plague developing nations, and they require large-scale international financing of water supply and water treatment projects.
External links:
- WHO hepatitis E factsheet (http://www.who.int/mediacentre/factsheets/fs280/en/)