A recombinant HEV vaccine has been developed and licensed in China. It is >95 percent efective for 12 months after vaccination. Long-term eicacy is 87 percent, and protective titers are maintained for up to 4.5 years (Zhang, 2015). Preliminary data from inadvertently vaccinated pregnant women show no adverse maternal or fetal events (Wu, 2012). At this time, it is unclear if this Chinese-licensed vaccine is efective in other areas of the world where other genotypes predominate. Genotype 4 is most common in China, and types 2 and 3 are more common in the Americas. A Food and Drug Administration (FDA) approved vaccine is not available at this time.
Hepatitis E is found worldwide, and although the highest prevalence is in east Asia, the CDC (2015) lists Mexico as a highly endemic country. Seroprevalence rates vary by age and geography, but overall seroprevalence rates of 10 percent have been reported. Durango State has the highest rate (37 percent) (Fierro, 2016).
Hepatitis G is the former name of an RNA flavivirus now known as HPvG or human pegivirus. This blood-borne infection of the liver, spleen, bone marrow, and mononuclear cells of the peripheral blood does not actually cause hepatitis (Chivero, 2015). It is thought to infect 750 million people worldwide, with up to two times that many with evidence of past infection. It may modulate the immune response, particularly during coinfection with HIV. Currently, no treatment aside from basic blood and body luid precautions is recommended. Vertical transmission (to the fetus/infant) and horizontal transmission (to peers) has been described (Trinks, 2014).
his is a generally progressive chronic hepatitis that is important to distinguish from other forms. Autoimmune hepatitis is more common in women and frequently coexists with other types of autoimmune disease, particularly autoimmune thyroid disease and Sjogren syndrome. Symptoms are typical of acute and chronic hepatitis, but one quarter may be asymptomatic. Rates of cirrhosis vary worldwide, but in western countries autoimmune hepatitis is more common and is characterized by multiple autoimmune antibodies such as antinuclear antibodies (ANA) and anti-smooth muscle antibody. Type 2 autoimmune hepatitis has an even higher prevalence in females and typically a more aggressive presentation. he incidence peaks in childhood and adolescence, before peak reproductive years. Treatment employs corticosteroids, alone or combined with azathioprine. Failure to respond to these two agents is more frequent in those with type 2 disease, and nearly all women with type 2 disease require more intensive therapy that is sustained long term (Vierling, 2015). In some patients with progressive disease and cirrhosis, hepatocellular carcinoma develops. In general, autoimmune hepatitis-especially when severeincreases the risk of adverse pregnancy outcomes.