Identification of continuous epitopes of the envelope glycoprotein of dengue type 2 virus.

We reacted 490 hexapeptides homologous to the amino acid sequence of the dengue 2 (DEN-2) virus envelope glycoprotein with antisera from 7 patients with primary DEN-2 virus infections to identify the continuous epitopes recognized by human IgG. There were 124 peptides in 25 clusters (domains) that bound 2 or more antisera. Twenty-two peptides in 7 domains bound all 7 convalescent DEN-2 virus antisera tested, and thus appeared to represent immunodominant epitopes. The evidence that these domains represents continuous epitopes of the envelope glycoprotein is that peptide representing each domain bound multiple sera, peptide reactivity was highly ordered along the amino acid sequence, and in almost all cases, domains were regions of predicted hydrophilicity. Heterologous flavivirus antisera also exhibited binding to the majority of peptides reactive with anti-DEN-2 virus sera, though 4 candidate DEN-2 specific epitopes were identified along with an immunodominant epitope common to dengue, Japanese encephalitis and West Nile viruses. Synthetic peptides representing these epitopes may prove to be useful for a variety of purposes.

National health programs in Thailand.

PIP: The main problem in Thailand medicine is maldistribution, both of manpower and facilities. Remedies include: 1) Fewer medical graduates are leaving the country for further studies in the West, a result of rising nationalism and better training at home. 2) The preventive and c urative aspects are being combined under 1 ministry. 3) Pilot in-service training has been instituted to enable public health nurses to give routine care. 4) Medical schools are now requiring 3 years of work in rural areas and public health students are doing work in villages. 5) New medical schools are being situated regionally. When the national family planning program was begun in 1970 it was integrated with the existing maternal and child health care facilities. Because of the large number of personnel needing training, courses were only 1 week long. Everyone admits the deficiency of this, but it got a large body of manpower in the field quickly. Most work has been person-to-person contact although some mass media is being used today. In 1968 there were about 57,000 acceptors. By 1972 the total was 450,000; by 1974, 46 0,000. By 1972 most acceptors (78%) were receiving services in rural clinics whereas in earlier years services were concentrated in cities. The postpartum program is an important part of the service, as almost 50% of new acceptors adopt family planning within 6 months of the last birth. The Thai program has a continuation rate of 76% at 12 months, 63% at 24 months, and 48% at 48 months for the IUD. For the pill the continuation rates are 68% for 12 months and 53% for 24. These high rates are believed due to Thailand using no incentive payments, formal targets, or similar techniques. Most acceptors pay a small fee for the service, are highly motivated, and therefore continue use longer.^ieng