Hepatitis E

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Hepatitis E virus
Hepatitis E in the electron microscope
Classification of viruses
Type	Virus
Group	Group IV
Family	Hepeviridae
Genus	Hepevirus
Case
Hepatitis E virus

Hepatitis E is a viral hepatitis (liver inflammation) caused by infection by a virus, the virus of hepatitis E (HEV). Infection by this virus has been described for the first time in 1955 during an epidemic in New Delhi, India.

Virology

Viral particles have a diameter of 27 to 34 nanometers, have no envelope and contain single-stranded RNA and long approximately 7300 bases. This genome is said “to positive polarity” which means that the viral genome is directly translated by the cellular machinery and acts directly as messenger RNA. Viral particles have been highlighted for the first time in 1983, but its molecular structure was cloned in 1990 only.

It was originally classified in the caliciviridae family. However, its genome resembles very closely that of the rubella virus. It is now classified as a unique genus Hepevirus, himself Member single genus in the family of the Hepeviridae.

There are several genotypes, numbered 1 to 4. 3 Genotype is most common in Western countries and is often mild and asymptomatic. Genotypes 1, 2 and 4 are much more frequent in developing countries, giving more severe violations and a public health problem.

Epidemiology

The incidence of hepatitis E is higher among adults between 15 and 40 years. Although children also often acquire this infection, they are less often a symptomatic infection. Mortality rates are generally low, because hepatitis E is a disease autoimmune “spontaneous healing”, where it usually disappears on its own and found the patient health without treatment.

However, during the term of l ‘ infection (usually several weeks), the disease alters seriously physical individual capabilities, the clinical picture may include fatigue, nausea and vomiting, jaundice (jaundice), dark urine and stool discoloured, and a loss of sometimes substantial weight, if hepatitis severe aigûe.

Hepatitis E is sometimes changing to a serious disease of the liver, and is fatal in about 2% of cases. Clinically, it looks like hepatitis A, but in pregnant women the disease is more severe and often associated with a clinical syndrome called “fulminant hepatitis”. Pregnant women, especially in the third quarter, show a rise in the mortality rate of the disease to about 20%. Other subjects at risk include people immunocompromised and those with already underlying chronic liver disease, including people with alcoholic cirrhosis.

Characteristics

Hepatitis E is very common in most developing countries and common in all countries to the hot climate. It is very widespread in Southeast Asia, North Africa and the centre, in India and in Central America. It is mainly spread through fecal contamination of water and food supply. Direct transmission from person to person is rare. Outbreaks of hepatitis E occur more often after heavy rains and monsoons because of the disruption of water supply they entail. Principal homes are located in New Delhi, India (30000 case in 1955-1955), in Burma (20000 case in 1976-1977), in Kashmir, in India (52000 case in 1978), Kanpur, India (79000 case in 1991), and China (100000 cases between 1986 and 1986).

In developed countries, hepatitis E virus is sometimes indigenous, that is, people are not in the categories of persons say risk, returning from a trip abroad. Hepatitis E patients are not detected, because before the rarity of this disease and in the absence of reasonable suspicion, health services do not think this possibility. One can see in hospital service of hepatology of patients with acute severe hepatitis undergoing very many tests (MRI, Fibrotest TM, biopsie…) including even research of orphan like Wilson disease diseases, for the medical team think E hepatitis that may finally be the cause of the disease. Hepatitis E is a disease notifiable in Germany but not France, or the observation network is little remained organized until 2009.

Yet statistics show that the cases are on the increase. In 2008, a study in the southwestern 529 blood donor samples showed that the anti-HEV IgG antibodies were present in 16.6% of cases, with an average of 14.2% among blood donors of the urban area of Toulouse and 20% in from donors of the rural areas of the Ariège, hunters with the highest prevalence rates. Among the tested cases, 293 had never traveled out of France, and 15% of them had anti-virus of hepatitis E IgG antibodies.

Animal reservoir

Domestic animals have been designated to serve as a reservoir for hepatitis E virus, in some studies showing infection rates above 95% in domestic pigs.

In 2003, a. Kuno reported the case of a 47-year-old man disease, and that the cat had antibody evidence of previous infection. Transmission after consumption of raw meat of deer and wild boar meat has also been reported. The rate of transmission to man by this route and its importance for public health are still poorly defined. Rats are also carriers of the virus.

More recently, in 2007, two cases of France patients revealed that the couple reached had consumed pork meat dried in the South of the country, a few weeks before reporting the disease. The authors refer to the consumption of pork raw or undercooked likely responsible for indigenous cases in France. This hypothesis was confirmed by the French food safety agency that made on 30 April 2009, a notice confirming the possibility of transmission of this virus by sausages raw pork liver base.

Different elements are indeed support it:

• Hepatitis E present in pig farms and humans are of the same genotype (there are 4 virus genotypes)
• the porcine population is considered as a reservoir of the virus in Spain, the Netherlands and the United States
• And finally, a convergence of elements to lowest granularity, for example the prevalence rate twice as high among swine veterinarians than in non-swine veterinarians

Recent epidemics

In 2004, occurred two major epidemics, both in sub-Saharan Africa. There was an outbreak in Chad, in which, as of September 27, there were 1442 cases and 46 deaths. Sudan, which has recently troubled by conflict (see civil war in Darfur), also known a major outbreak of hepatitis E. From September 28, reported 6861 cases and 87 deaths, mainly in the Western region of Darfur. UNICEF, doctors without borders, the Red Cross, and other international health organizations are currently working to increase supplies in SOAP, digging new wells, and water supply as well as to the treatment of reservations by chlorine. However, existing resources are not sufficient, necessary funds and personnel are severely lacking in the region to ensure the health and quality of life of populations. Increasingly, hepatitis E spreads in developed countries with cases reported to the United Kingdom, the United States and the Japan. The disease is regarded as a zoonosis. Deer and pigs are two species which have been involved.

Since 2002, the monitoring of hepatitis E in France is provided by the Centre national virus enteric transmission (hepatitis A and E, or RSS, located in the grounds of the hospital Paul Bush in Paris.)

French health authorities said in May 2009 and then in April 2011 have identified an increase in particular in region Provence Alpes Cote d’Azur, due to the consumption of offal sausage raw type Figatelli.

According to the weekly epidemiological Bulletin of August 25, 2009, 264 cases of hepatitis E Aboriginal, 51 cases of hepatitis E imported and 54 cases of hepatitis E in the epidemiological context not specified have been reported in France from 2006 to 2008. Hepatitis E is a rare disease in France, she knows a strong growth: the CNR was diagnosed in 2006, 38 cases of hepatitis E in 2006, 113 cases in 2007, 218 in 2008 and 260 cases in 2009.

Prevention

Improving sanitation is the most important measure. It is to treat and dispose of human waste, to improve the quality of water supply, improve personal hygiene and the health quality of the preparation of food. Thus, the strategies of prevention of this disease are similar to those of many other infections that afflict developing countries who need and large scale international financing for water supply and water treatment projects. A vaccine based on protein viral recombinant has been developed by the army American and company pharmaceutical and tested in 2007 in a population at high risk (military personnel of a developing country). The vaccine appears to be effective and safe, but has not been on the market, possibly for commercial reasons. A second vaccine, Chinese manufacturing, seems to have an also good efficiency and tolerance.

Finally, as regards the meats to pork liver base, it is recommended cook at heart, although this notion remains unclear. In addition the French health authorities recommend persons who may present a serious form of HVE increased risk (pregnant women, immunocompromised persons and persons with underlying liver disease) to avoid any product deli raw pork liver base.