Prevention, diagnosis, and management of Japanese encephalitis in children

Abstract

Japanese encephalitis is the single largest cause of viral encephalitis in the world today. It is caused by a Flavivirus whose natural cycle occurs in mosquito and vertebrate hosts (ardeid birds and pigs) and man is an incidental dead-end host. It tends to occur in outbreaks in poor rural regions of Asia where rice growing and pig rearing are a way of life. The illness has three stages -a prodromal stage with fever, headache, vomiting, and other nonspecific symptoms, an acute encephalitic stage with convulsions, coma, and signs of raised intracranial tension, and a convalescent stage. Differential diagnosis is very wide and even during epidemics it can be mimicked by many infectious and noninfectious disorders. The mainstay of laboratory diagnosis is the antibody capture enzyme-linked immunosorbent assay technique in cerebrospinal fluid. Treatment is essentially supportive and no antiviral has yet proven effective in randomized controlled trials. The mainstay of prevention is by vaccination. Many effective and safe vaccines are available and the IXIARO ® vaccine -an inactivated vaccine from the SA-14-14-2 strain grown in vero cells -has received US Food and Drugs Administration approval. Japanese encephalitis control is thus a global health priority.

New strains of Japanese encephalitis virus circulating in Shanghai, China after a ten-year hiatus in local mosquito surveillance

“…In China, JE cases are mainly concentrated in the eastern and southwestern regions, and no local cases have been reported in Xinjiang or Qinghai to date [6]. The principal JEV-susceptible population is children below 15 years of age, and the virus has an incubation period of 5–15 days [13]. Clinically, since the virus can cross the blood brain barrier, JE manifests as a high fever and generalized tonic spasms; thus, in severe cases, irreversible neurologic damage, resulting in consciousness disorders and serious dystonia, may be observed [14, 15].…”

“…p. pallens mosquito larvae in Xi’an, China and licensed in 1988 [18]. Owing to its advantages, such as increased efficacy at a lower dose, fewer side effects, and lower cost [13, 19, 20], the attenuated live vaccine SA14-14-2 is now the main vaccine used in China. Moreover, since 2008, the JEV vaccine has been available free of charge to children 0–15 years-old in China, significantly reducing the spread of JEV [21].…”

Japanese Encephalitis Virus infection in South-East Asia: an immuno-epidemiological twist

“…Several murine models also described the beneficial therapeutic roles of IgM, TLR7, type I IFNs in JE pathogenesis. Similarly, chemicals like rivabarin, arctigenin, curcumin, minocycline and glucosidase inhibitors help in regulating the cellular apoptosis, activation and differentiation of microglia, caspase-3 activation, and the induction of pro-inflammatory mediators in JEV infection [10,17,25].…”

“…Nearly 4 billion people are at risk of JE. And the occurrence severity is resulting almost 25% fatality, neuropsychiatric sequelae in 30% of cases [9], as well as permanent neurological disability in Southeast Asian infant survivors [10]. Significant outbreaks of JE transmission intensify during the rainy season due to the rapid breeding of vector populations.…”

Seasons and water container types affecting Culex spp. in southern Thailand

“…Culex mosquitoes are responsible for spreading various types of infectious diseases, such as Japanese encephalitis, West Nile fever, St. Louis encephalitis, filariasis, and avian malaria (Lalubin et al 2013). Among these diseases, Japanese encephalitis is endemic in more than 20 countries (Kumar 2014), and is spreading out to new territories very quickly (Erlanger et al 2009); around three billion people are at risk of this disease (Shad and Andrew 2016). Filariasis is known as another major health problem worldwide.…”