Risk factors in dengue shock syndrome: a prospective epidemiologic study in Rayong, Thailand. I. The 1980 outbreak.

In January 1980, the municipal area of Rayong, Thailand, and contiguous suburban villages were chosen for a long-term study on dengue epidemiology. From 3,185 children randomly sampled in schools and households, the population prevalence of neutralizing antibody to the four dengue serotypes was estimated. To estimate the incidence of infection with each dengue virus serotype (dengue seroconversions), first grade children were re-bled in January 1981 (cohort study).

Original antigenic sin in dengue.

Sequential blood samples were obtained from eight Thai children before, during and 3-5 months after hospitalization for dengue shock syndrome. All patients experienced a secondary-type antibody response as evidenced by hemagglutination-inhibition antibody responses in acute and convalescent sera. Dengue 2 viruses were recovered from two patients.

Serological and virological studies on patients with dengue hemorrhagic fever (DHF) in Chanthaburi province, Thailand. II. Serological characteristics of viruses isolated from DHF patients using a clone of Singh's Aedes albopictus cells.

Four strains of dengue (DEN) virus were isolated using C6/36 cells, a clone of Singh's Aedes albopictus cells, from acute phase sera of DHF patients in Thailand in 1978. The isolates grown and passaged in C6/36 cells were not neutralized appreciably by standard rabbit antisera against each of the 4 types of DEN virus, but their serotypes could be identified by complement fixation (CF) tests. After the 4th or 10th passage in suckling mouse brain (SMB), however, three of the four strains showed type-specific reactions in neutralization (N) tests against the standard antisera.

Serological and virological studies on patients with dengue hemorrhagic fever (DHF) in Chanthaburi province, Thailand. I. Serological studies on paired sera from DHF patients by neutralization (N), hemagglutination inhibition (HI) and staining tests.

Twenty paired sera were collected from DHF patients admitted to the provincial hospital of Chanthaburi, Thailand in 1978. They were tested by the N and HI tests and a newly developed staining test against all four serotypes of dengue (DEN) virus and Japanese encephalitis (JE) virus. Four patients were demonstrated to be cases of primary DEN infection and the other 16 to be cases of secondary DEN infection.

Hemagglutination-inhibiting immunoglobulin A antibody in the serum of patients with dengue hemorrhagic fever.

In convalescent-phase sera of patients with dengue hemorrhagic fever, hemagglutination-inhibiting (HI) antibody of immunoglobulin (Ig) A class, in both monomeric and oligomeric forms, was detected. It was found to be less type-specific than IgM HI, and as broadly cross-reacting as IgG HI antibodies.