A cross sectional study found differential risks for COVID-19 seropositivity amongst health care professionals in Chile.

Objective: Health care workers (HCWs) are at increased risk for SARS-CoV-2 infection, however not all face the same risk. We aimed to determine IgG/IgM prevalence and risk factors associated with seropositivity in Chilean HCWs.

Study Design And Setting: This was a nationwide, cross-sectional study including a questionnaire and COVID-19 lateral flow IgG/IgM antibody testing.

The human gut microbiome of Latin America populations: a landscape to be discovered.

Purpose Of Review: The gut microbiome is critical for human health, and its alteration is associated with intestinal, autoimmune and metabolic diseases. Numerous studies have focused on prevention or treatment of dysbiotic microbiome to reduce the risk or effect of these diseases. A key issue is to define the microbiome associated with the state of good health.

Rotavirus Serum IgA Immune Response in Children Receiving Rotarix Coadministered With bOPV or IPV.

Background: Vaccine schedules including bivalent oral and inactivated poliovirus vaccines will replace trivalent oral poliovirus vaccines in 2016.

Methods: We evaluated rotavirus immunoglobulin A seroresponses when the second dose of Rotarix at 16 weeks was given concomitantly with inactivated or bivalent oral poliovirus vaccines.

Results: Rotavirus immunoglobulin A seroresponse rate at week 28 was 15% lower in recipients of bivalent oral poliovirus vaccines compared with inactivated poliovirus vaccines.

Persistent and transient Helicobacter pylori infections in early childhood.

Background: Helicobacter pylori, the main cause of peptic ulcer disease and gastric cancer in adult populations, is generally acquired during the first years of life. Infection can be persistent or transient and bacterial and host factors determining persistence are largely unknown and may prove relevant for future disease.

Methods: Two cohorts of healthy Chilean infants (313 total) were evaluated every 3 months for 18-57 months to determine pathogen- and host-factors associated with persistent and transient infection.

Dynamics of Helicobacter pylori detection in stools during the first 5 years of life in Chile, a rapidly developing country.

Background: : Helicobacter pylori colonization/infection can be transitory or persistent, conditions that have not been thoroughly evaluated in young children. We aimed to characterize the dynamics of H. pylori stool detection and to determine host and environmental factors and symptoms associated with persistence.

Enteric viruses in wastewaters: an interesting approach to evaluate the potential impact of rotavirus vaccination on viral circulation.

Rotavirus and norovirus are the leading causes of acute gastroenteritis worldwide. Both viruses share features such as low infectious dose, high stool concentration and prolonged survival in the environment, including water. However, they differ in several aspects, reflecting potential differences in their interactive capacities with the environment and host.

Immunogenicity and tolerability of a multicomponent meningococcal serogroup B (4CMenB) vaccine in healthy adolescents in Chile: a phase 2b/3 randomised, observer-blind, placebo-controlled study.

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, observer-blind, placebo-controlled, study at 12 sites in Santiago and Valparaíso, Chile.

Prospective characterization of norovirus compared with rotavirus acute diarrhea episodes in chilean children.

Background: Rotavirus and more recently noroviruses are recognized as main causes of moderate to severe acute diarrhea episodes (ADE) in children < or =5 years of age. Comparing epidemiologic and clinical features of norovirus to rotavirus ADE will aid in the decision-making process required to develop norovirus vaccines.

Methods: Surveillance for ADE occurring in children < or =5 years of age was implemented in the emergency department (ED) and ward of a large hospital in Santiago and Valparaiso, and in 4 outpatient clinics in Santiago.

Symptomatic and asymptomatic rotavirus and norovirus infections during infancy in a Chilean birth cohort.

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 in the Metropolitan Region of Chile are being followed for 18 months in 2 outpatient clinics.

Rotavirus vaccines for the developing world.

Purpose Of Review: The authors discuss the most relevant information in the field of rotavirus vaccines published from October 2007 to June 2009; new information on the virus, host response and disease burden that relate to our understanding of vaccine mechanisms and impact are discussed. The review will focus on the role of the vaccines for the developing world but this does not preclude the relevance of these vaccines for children living in the industrialized world.

Recent Findings: Immune mechanisms involved in rotavirus-associated immunity potentially relevant for vaccine-associated immunity continue to be identified including anti-NSP4 antibodies, cellular and mucosal mechanisms.

Novel recombinant norovirus causing outbreaks of gastroenteritis in Santiago, Chile.

Capsid and polymerase (RdRp) genes of 13 norovirus outbreak strains from Chile were compared. The genes sequences were discordant for five strains, and recombination was confirmed for two of them by amplification of a 1,360-bp gene segment containing a fragment of both genes. These strains belonged to a novel genogroup by RdRp sequence and to genogroup GII/3 by capsid sequence.

Caliciviruses and foodborne gastroenteritis, Chile.

Human caliciviruses caused 45% of 55 gastroenteritis outbreaks occurring in Santiago, Chile, during 2000-2003. Outbreaks affected ?99 persons, occurred most commonly in the home, and were associated with seafood consumption. Thirteen outbreak strains sequenced were noroviruses, including 8 GII, 2 GI, and 3 belonging to a novel genogroup.

Early hospital discharge followed by outpatient management versus continued hospitalization of children with cancer, fever, and neutropenia at low risk for invasive bacterial infection.

Purpose: To compare outcome and cost of ambulatory versus hospitalized management among febrile neutropenic children at low risk for invasive bacterial infection (IBI).

Patients And Methods: Children presenting with febrile neutropenia at six hospitals in Santiago, Chile, were categorized as high or low risk for IBI. Low-risk children were randomly assigned after 24 to 36 hours of hospitalization to receive ambulatory or hospitalized treatment and monitored until episode resolution.