Centers for Disease Control and Prevention

About: Centers for Disease Control and Prevention is a government organization based out in Atlanta, Georgia, United States. It is known for research contribution in the topics: Population & Public health. The organization has 58238 authors who have published 82592 publications receiving 4405701 citations. The organization is also known as: CDC & Centers for Disease Control and Prevention (CDC).

The National Birth Defects Prevention Study.

Abstract: The National Birth Defects Prevention Study was designed to identify infants with major birth defects and evaluate genetic and environmental factors associated with the occurrence of birth defects. The ongoing case-control study covers an annual birth population of 482,000 and includes cases identified from birth defect surveillance registries in eight states. Infants used as controls are randomly selected from birth certificates or birth hospital records. Mothers of case and control infants are interviewed and parents are asked to collect buccal cells from themselves and their infants for DNA testing. Information gathered from the interviews and the DNA specimens will be used to study independent genetic and environmental factors and gene-environment interactions for a broad range of birth defects. As of December 2000, 7,470 cases and 3,821 controls had been ascertained in the eight states. Interviews had been completed with 70% of the eligible case and control mothers, buccal cell collection had begun in all of the study sites, and researchers were developing analysis plans for the compiled data. This study is the largest and broadest collaborative effort ever conducted among the nation's leading birth defect researchers. The unprecedented statistical power that will result from this study will enable scientists to study the epidemiology of some rare birth defects for the first time. The compiled interview data and banked DNA of approximately 35 categories of birth defects will facilitate future research as new hypotheses and improved technologies emerge.

Early Alterations of the Receptor-Binding Properties of H1, H2, and H3 Avian Influenza Virus Hemagglutinins after Their Introduction into Mammals

Abstract: Interspecies transmission of influenza A viruses circulating in wild aquatic birds occasionally results in influenza outbreaks in mammals, including humans. To identify early changes in the receptor binding properties of the avian virus hemagglutinin (HA) after interspecies transmission and to determine the amino acid substitutions responsible for these alterations, we studied the HAs of the initial isolates from the human pandemics of 1957 (H2N2) and 1968 (H3N2), the European swine epizootic of 1979 (H1N1), and the seal epizootic of 1992 (H3N3), all of which were caused by the introduction of avian virus HAs into these species. The viruses were assayed for their ability to bind the synthetic sialylglycopolymers 3'SL-PAA and 6'SLN-PAA, which contained, respectively, 3'-sialyllactose (the receptor determinant preferentially recognized by avian influenza viruses) and 6'-sialyl(N-acetyllactosamine) (the receptor determinant for human viruses). Avian and seal viruses bound 6'SLN-PAA very weakly, whereas the earliest available human and swine epidemic viruses bound this polymer with a higher affinity. For the H2 and H3 strains, a single mutation, 226Q-->L, increased binding to 6'SLN-PAA, while among H1 swine viruses, the 190E-->D and 225G-->E mutations in the HA appeared important for the increased affinity of the viruses for 6'SLN-PAA. Amino acid substitutions at positions 190 and 225 with respect to the avian virus consensus sequence are also present in H1 human viruses, including those that circulated in 1918, suggesting that substitutions at these positions are important for the generation of H1 human pandemic strains. These results show that the receptor-binding specificity of the HA is altered early after the transmission of an avian virus to humans and pigs and, therefore, may be a prerequisite for the highly effective replication and spread which characterize epidemic strains.

Status of Childhood Asthma in the United States, 1980–2007

Abstract: Centers for Disease Control and Prevention data were used to describe 1980-2007 trends among children 0 to 17 years of age and recent patterns according to gender, race, and age. Asthma period prevalence increased by 4.6% per year from 1980 to 1996. New measures introduced in 1997 show a plateau at historically high levels; 9.1% of US children (6.7 million) currently had asthma in 2007. Ambulatory care visit rates fluctuated during the 1990 s, whereas emergency department visits and hospitalization rates decreased slightly. Asthma-related death rates increased through the middle 1990 s but decreased after 1999. Recent data showed higher prevalence among older children (11-17 years), but the highest rates of asthma-related health care use were among the youngest children (0-4 years). After controlling for racial differences in prevalence, disparities in adverse outcomes remained; among children with asthma, non-Hispanic black children had greater risks for emergency department visits and death, compared with non-Hispanic white children. For hospitalizations, for which Hispanic ethnicity data were not available, black children had greater risk than white children. However, nonemergency ambulatory care use was lower for non-Hispanic black children. Although the large increases in childhood asthma prevalence have abated, the burden remains large. Potentially avoidable adverse outcomes and racial disparities continue to present challenges. These findings suggest the need for sustained asthma prevention and control efforts for children.

Global Epidemiology of Influenza: Past and Present

Abstract: Pandemics are the most dramatic presentation of influenza. Three have occurred in the twentieth century: the 1918 H1N1 pandemic, the 1957 H2N2 pandemic, and the 1968 H3N2 pandemic. The tools of molecular epidemiology have been applied in an attempt to determine the origin of pandemic viruses and to understand what made them such successful pathogens. An excellent example of this avenue of research is the recent phylogenetic analysis of genes of the virus that caused the devastating 1918 pandemic. This analysis has been used to identify evolutionarily related influenza virus genes as a clue to the source of the pandemic of 1918. Molecular methods have been used to investigate the avian H5N1 and H9N2 influenza viruses that recently infected humans in Hong Kong. Antigenic, genetic, and epidemiologic analyses have also furthered our understanding of interpandemic influenza. Although many questions remain, advances of the past two decades have demonstrated that several widely held concepts concerning the global epidemiology of influenza were false.