Dengue Hemorrhagic Fever in a Japanese Traveler with Pre-existing Japanese Encephalitis Virus Antibody

Abstract

An adult Japanese man who had just returned from Thailand developed dengue hemorrhagic fever (DHF). A primary infection of dengue virus (DENV) was confirmed, specifically DENV serotype 2 (DENV-2), on the basis of the detection of the virus genome, a significant increase in the neutralizing antibody and the isolation of DENV-2. DHF is often observed following a secondary infection from another serotype of dengue virus, particularly in children, but this case was a primary infection of DENV. Japan is a non-endemic country for dengue disease. In fact, only Japanese encephalitis (JE) is known to be a member of the endemic flavivirus family. In this study, IgG antibody against Japanese encephalitis virus (JEV) was detected. JEV belongs to the family of dengue virus and prevails in Japan, particularly Kyushu. Among many risk factors for the occurrence of DHF, a plausible candidate could be a cross-reactive antibody-dependent enhancement (ADE) mechanism caused by JEV antibody. This indicates that most Japanese travelers who living in dengue non-endemic areas, particularly Kyushu, should be aware of the occurrence of DHF.

Japanese encephalitis vaccine-facilitated dengue virus infection-enhancement antibody in adults

“…Studies have also shown that JE vaccines have limited effect on the severity of dengue disease [ 35 ]. However, there is limited and inconclusive evidence regarding pre-existing immunity to JEV and subsequent symptomatic or severe presentation of DENV infection [ 12 , 36 ]. In flavivirus infection, the ability to mount an early and vigorous antibody response is associated with better clinical outcomes, indicating that anamnestic, anti-flavivirus immune response induced by prior DENV and JEV infection, for example, is important in conferring protection, or comparatively milder disease outcomes [ 37 – 39 ].…”

Неугодная Иммунология

“…До 2 % таких жителей на протяжении жизни переболевают японским энцефалитом и имеют нейтрализующие антитела к его возбудителю -вирусу японского энцефалита. Их коли-чество среди людей моложе 50 лет постоянно увеличива-ется из-за осуществления различных программ по вак-цинации населения против японского энцефалита, тем самым увеличивается риск геморрагического течения ли-хорадки Денге при первичном заражении DENV [107]). …”

“…Исследовате-ли считают, что программы по вакцинации населения против вируса японского энцефалита, в тех районах, где одновременно с ним циркулирует и MVEV, могут способствовать развитию эпидемии энцефалита до-лины Мюррей. В более поздних работах обсуждалась связь с предыдущей вакцинацией против японского энцефалита тяжелого течения лихорадки Денге у жи-телей Японии [107].…”

Progress towards understanding the pathogenesis of dengue hemorrhagic fever

“…The mechanism of ADE remains only partially understood. Fcγ receptor (FcγR)-mediated uptake of virionantibody complexes into permissive cells may be one explanation for the enhancement of DENV infection (Sato et al, 2015). FcγR is a multi-subunit complex that is distributed on the surfaces of many types of immune cells, such as dendritic cells, macrophages and mast cells, and recognizes the Fc regions of immunoglobulins.…”