RESUMO
Serum samples from 726 Ecuadorian children who underwent natural rotavirus (RV) exposure were tested for neutralizing serum antibodies against two serotype 6 (ST6) human RV (HRV) isolates from Italy, PA151 and PA169, and two ST6 bovine RV (BRV) isolates, NCDV and UK. Gene 4 was distinct in all four ST6 strains. Ninety-one, 56, 67, and 65 serum samples neutralized HRV PA151 (13%), HRV PA169 (8%), BRV NCDV (9%), and BRV UK (9%), respectively. A total of 44 of the 91 serum samples which neutralized HRV PA151 did not neutralize the other three ST6 RV strains. In addition, we identified three serum samples that neutralized HRV PA151 but none of the six human or four animal RV STs. However, we failed to identify serum samples that neutralized HRV PA169 without neutralizing at least one of the major HRV STs. With a hospital-based serum collection from German children (excluding gastroenteritis patients), we identified 3 out of 197 serum samples tested that neutralized HRV PA151 specifically, whereas none neutralized HRV PA169 exclusively. None of the 71 German infants hospitalized with primary RV gastroenteritis showed a PA151- or a PA169-specific antibody response.
Assuntos
Anticorpos Antivirais/sangue , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Adulto , Pré-Escolar , Equador/epidemiologia , Alemanha/epidemiologia , Humanos , Lactente , Recém-Nascido , Testes de Neutralização , Rotavirus/classificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/microbiologia , Estudos Soroepidemiológicos , SorotipagemRESUMO
Reassortants between serotype 3 SA11 and serotype 6 NCDV rotaviruses were used to determine the relative amounts of serum-neutralizing antibody to VP4 and VP7 of serotype 3 SA11 rotavirus in children after natural rotavirus exposure. Sera from Ecuadorian children of a population-based study and sera from children of a hospital-based study in Germany (excluding diarrhea patients) demonstrated high titers of VP7-specific but only low titers of VP4-specific antibodies. In contrast, paired sera from German children hospitalized with a symptomatic primary rotavirus gastroenteritis demonstrated a titer increase to VP4 more frequently than to VP7 protein by neutralization test and immunoblotting. For these rotavirus patients, we provided, previously, direct evidence for the development of cross-neutralizing antibodies.
Assuntos
Anticorpos Antivirais/imunologia , Antígenos Virais , Proteínas do Capsídeo , Infecções por Rotavirus/imunologia , Rotavirus/imunologia , Anticorpos Antivirais/isolamento & purificação , Capsídeo/imunologia , Pré-Escolar , Equador , Alemanha Ocidental , Humanos , Imunoglobulina A/imunologia , Imunoglobulina A/isolamento & purificação , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Imunoglobulina M/imunologia , Imunoglobulina M/isolamento & purificação , Lactente , Testes de Neutralização , Rotavirus/classificação , SorotipagemRESUMO
A randomized placebo-controlled double-blind field trial of RIT 4237 attenuated rotavirus vaccine in Lima, Peru, evaluated the protection against diarrheal illness by one, two, or three doses of vaccine. There were 391 children, 2-18 months old, studied for the occurrence of diarrhea during the 18 months after vaccination. Three doses of the vaccine provided 40% protection against any diarrheal illness associated with rotavirus alone but 58%-75%; protection against the more severe rotaviral illnesses. The vaccine appeared to be more efficacious when it was administered to children in the first year of life. Three doses provided up to 89% efficacy against more severe diseases due to serotype 1 rotavirus, and one dose also afforded significant protection. The protection was lower, even with three doses, against serotype 2 rotavirus. This vaccine trial has provided important insights on how such trials should be conducted and on the serotype-specificity of protection from rotavirus infection. Future vaccines should be able to protect against severe disease caused by all rotavirus serotypes and must work in developing countries where rotavirus is the most important cause of diarrheal mortality.