Miguel O'Ryan

Learn More
BACKGROUND The safety and efficacy of an attenuated G1P[8] human rotavirus (HRV) vaccine were tested in a randomized, double-blind, phase 3 trial. METHODS We studied 63,225 healthy infants from 11 Latin American countries and Finland who received two oral doses of either the HRV vaccine (31,673 infants) or placebo (31,552 infants) at approximately two(More)
BACKGROUND Noroviruses (NoVs) are the most common cause of viral gastroenteritis. Their high incidence and importance in health care facilities result in a great impact on public health. Studies from around the world describing increasing prevalence have been difficult to compare because of differing nomenclatures for variants of the dominant genotype,(More)
BACKGROUND Peak incidence of rotavirus gastroenteritis is seen in infants between 6 and 24 months of age. We therefore aimed to assess the 2-year efficacy and safety of an oral live attenuated human rotavirus vaccine for prevention of severe gastroenteritis in infants. METHODS 15 183 healthy infants aged 6-13 weeks from ten Latin American countries(More)
BACKGROUND Effective glycoconjugate vaccines against Neisseria meningitidis serogroups A, C, W-135, and Y have been developed, but serogroup B remains a major cause of severe invasive disease in infants and adolescents worldwide. We assessed immunogenicity and tolerability of a four-component vaccine (4CMenB) in adolescents. METHODS We did a randomised,(More)
More than one billion diarrhea episodes occur every year among children younger than 5 years of age in socioeconomically developing countries causing 2 to 2.5 million deaths. More than twenty viral, bacterial, and parasitic enteropathogens are currently associated with acute diarrhea. Rotavirus and diarrheagenic Escherichia coli are the most common(More)
Rotavirus is a double-stranded RNA virus that is characterized by substantial genetic diversity. The various serotypes of rotavirus have been determined by the presence of neutralizing epitopes on the outer capsid of the protein shell. At present, 5 rotavirus serotypes (G1, G2, G3, G4, G9) are the predominant circulating strains, accounting for(More)
BACKGROUND In Chile, the novel influenza A (H1N1) epidemic began in the middle-high income area of Santiago. Clinical and laboratory surveillance was intensified with the aim to characterize the epidemic and determine its impact in a large hospital setting. METHODS Demographic and clinical data were obtained from all patients whose symptoms met the(More)
Worldwide, rotaviruses are the single most important agents of severe gastroenteritis in infants and young children. Globally, it is estimated that every year rotavirus gastroenteritis causes more than 125 million episodes of diarrhea and nearly 527,000 deaths, mainly in developing countries. The development of new effective and safe rotavirus vaccines was(More)
Rotarix(®) was first licensed in 2004 and rapidly introduced into private and public markets worldwide. In a previous 2009 article, we reviewed the impact of rotavirus-associated disease, the rationale for different vaccines, prelicensure efficacy studies and cost-effectiveness studies for Rotarix. As of September 2011, Rotarix had been licensed in 123(More)
BACKGROUND Rotavirus and more recently norovirus have been recognized as 2 of the most common causes of acute diarrhea in children. Comparative analysis of these infections in a birth cohort has not been performed and can provide relevant insight on clinical and viral behaviors. METHODS Mother-infant pairs from middle-low socioeconomic background living(More)