Asymptomatic SARS-CoV-2 Infection in Havana, Cuba, March-June 2020: Epidemiological Implications.

Introduction: The percentage of asymptomatic COVID-19 cases worldwide is estimated at 18-50%; 53% in Cuba specifically, and 58% in Havana, the Cuban capital and the 2020 epicenter of the country's COVID-19 epidemic. These figures, however, do not represent the transmission capacity or behavior of asymptomatic cases. Understanding asymptomatic transmission's contribution to SARS-CoV-2 spread is of great importance to disease control and prevention.

Clinical-Epidemiological Characteristics of the First Patients Diagnosed with COVID-19 in Cuba.

Introduction: COVID-19 is caused by the novel coronavirus SARS-CoV-2 and was declared a pandemic on March 11, 2020, the same day that the first cases in Cuba were diagnosed. In Cuba, all confirmed cases of COVID-19 were hospitalized from this point forward.

Objective: Characterize the first patients diagnosed with COVID-19 in Cuba.

[Air pollution, bronchial asthma, and acute respiratory infections in minors, Habana City].

Objective: To identify the relationship between emergency visits for acute respiratory illnesses, acute bronchial asthma crisis (ABAC) and acute respiratory infections (ARI), in children less than 14 years of age, and the daily changes of air pollutant levels, in two central hospitals of Havana City, between October 1st 1996 and March 16 1998.

Material And Methods: An ecological time series study was conducted. We assessed the relationship between the presence of acute respiratory illnesses, ABAC, and IRA, and exposure to levels of particles less than 10 microg/m3 (PM10), smoke, and sulfur dioxide (SO2); negative binomial regression models were used to assess latency periods of one to five days as well as the cumulative effect of seven days before the emergency visit.

[Levels of plasmatic lead in children 8-10 years of age and its relation to changes in visual-motor system and balance].

Objective: To assess the association between blood lead concentrations and visual-motor coordination and equilibrium in school age children.

Material And Methods: In November-December 1998, a cross-sectional study was conducted among 255 children aged 8-10, who attended public schools in Sector 1 of the Oaxaca State Public Education Institute. Data were collected using the Frostig Evaluation of Visual Perception test and the equilibrium subscale of the Frostig Movement Skills Test Battery.

Lead-glazed ceramic ware and blood lead levels of children in the city of Oaxaca, Mexico.

Although Mexico substantially reduced use of leaded gasoline during the 1990s, lead-glazed pottery remains a significant source of population exposure. Most previous studies of lead in nonoccupationally exposed groups in Mexico have been conducted in the Mexico City metropolitan area. Oaxaca, a poor southern state of Mexico, has a centuries-old tradition of use of low temperature lead-glazed ceramic ware manufactured mainly by small family businesses.