The epidemiology of hepatitis E virus infections in developed countries and among immunocompromised patients

Abstract

Hepatitis E virus (HEV) is an important cause of acute hepatitis in humans worldwide, both as epidemic and sporadic disease. Since the virus was identified in 1983, epidemics have occurred regularly in many countries across South and Southeast Asia when seasonal floods have contaminated drinking water supplies and in Africa during humanitarian crises among refugee populations without access to clean water. In addition, sporadic cases and small clusters of HEV infections have been recognized throughout the world in developed countries over the past couple of decades. This review will focus on emerging evidence of HEV infection as an under-recognized pathogen in Europe, the USA and other industrialized countries. We will discuss some of the issues associated with the recognition, diagnosis and treatment of these sporadic cases. We will also summarize the recent literature on autochthonous HEV infection among populations in developed countries in industrialized Europe, the USA, Japan and other industrialized Asian countries. We will review recent reports of acute and chronic HEV infections among transplant recipients and other immunocompromised individuals including HIV/AIDS patients.

Hepatitis E virus in the countries of the Middle East and North Africa region: an awareness of an infectious threat to blood safety

“…However, selective screening is to be recommended in certain circumstances. Recent evidence shows that HEV infection can take a severe or even fatal course resulting in liver failure in immunocompromised, pregnant women or patients with chronic liver disease [123,[125][126][127][128][129]. Since these patients often require blood transfusion, it is prudent that screening for HEV-RNA or at least for anti-HEV IgM in donated blood for these patients should be implemented as soon as possible.…”

Host Immune Status and Response to Hepatitis E Virus Infection

“…Whether these reports suggest that pregnancy or pregnancylike states may represent a risk factor for more severe clinical disease even in high-income countries where HEV-3 and HEV-4 circulate, or whether the paucity of such reports in the face of 10 to 20% population seroprevalence supports the increased virulence of genotype 1 viruses for pregnant women, is not certain. Severe infections during pregnancy in developing countries may be primarily a result of greater virulence of the human-adapted HEV-1 and HEV-2 genotypes, increased susceptibility of pregnant women in developing countries where these genotypes are endemic, or the epidemiologic conditions of exposure to these viruses (155,156). Also, in many developed-country settings, awareness of hepatitis E as a plausible diagnosis may be low, leading to missed cases and underdiagnosis of this infection.…”

Fetal and Neonatal Health Consequences of Vertically Transmitted Hepatitis E Virus Infection

“…However, the globally ubiquitous zoonotic HEV strains (genotypes 3 and 4) have more recently been identified as a cause of sporadic hepatitis in medically vulnerable patients and the general population in high-income countries. [4][5][6][7][8][9][10][11][12][13][14] High case-fatality ratios among pregnant women, particularly during the third trimester of pregnancy, remain an almost pathognomonic feature of hepatitis E epidemics caused by HEV genotype 1. [15][16][17][18][19][20][21] There is mounting evidence that hepatitis E is an important contributor to maternal morbidity and mortality in south Asia, even outside of periodic large outbreaks.…”