Control of Japanese encephalitis in India: a reality.

Japanese encephalitis is considered as a serious disease due to the complexity of the disease and lack of specific treatment. A secular trend towards declining of JE has been brought in China, Korea, and Japan with widespread use of JE vaccine. In India, the actual JE burden could be estimated only by strengthening diagnostic facilities for JE confirmation in hospitals. However, the available records at present indicate a rising trend in JE- occurrence and expansion of the disease into JE non-endemic areas, which cannot be ignored. JE control through vector control methods has limitations owing to sustainability and cost effectiveness of the programs. Under these circumstances, feasibility of JE vaccination in India has to be considered as a preventive measure, for which identification of risk areas, target populations to be immunized, cost-evaluation of immunization is emphasized. Since, JE vaccine is produced in India, extension of the availability of this vaccine into routine JE-immunization programs is not remote. China has proved that countries with limited sources can produce safe and effective JE vaccines.

Japanese encephalitis in India: an overview.

Japanese encephalitis (JE)-epidemics have been reported in many parts of the country. The incidence has been reported to be high among pediatric group with high mortality. The incidence of JE in recent times is showing an increasing trend. It appears that JE may become one of the major public health problems in India, considering the quantum of the vulnerable pediatric population, the proportion of JEV infections among the encephalitic children and wide scattering of JE-prone areas. JE burden can be estimated satisfactorily to some extend by strengthening diagnostic facilities for JE confirmation in hospitals and by maintenance of contact with the nearby referral hospitals to collect the particulars on JE cases. Vaccination proves to be the best to protect the individual against any disease. In the case of JE, it is essential to immunize the pigs (amplifying host) also to interrupt the transmission of the disease.

Naturally occurring plasmodium-specific IgA antibody in humans from a malaria endemic area.

Blood samples collected from individuals belonging to an endemic area in Uttar Pradesh, were tested for plasmodial antigen specific immunoglobulin A (IgA) by enzyme immuno assay using soluble extract of Plasmodium falciparum from culture. Among 773 (20·18%, P < 0·0001) samples 156 sera demonstrated a detectable seropositivity for antigen specific IgA. IgA levels were higher among individuals who experienced repeated attacks of malaria compared to acute infected patients. Among seropositive individuals the IgA titers were found increased with the age. Immunoglobulin isolated from sera having high level of IgA showed growth inhibitory effect in Plasmodium falciparum in vitro. A group of sera with high IgA antibody against Plasmodium falciparum crude antigen showed seronegativity with specific peptides. Statistically, no positive or negative correlations were observed between antigen specific IgG and IgA. However, there was a tendency towards negative correlation between IgA and IgM. Mechanisms for the parasite specific IgA production remain to be established.