View allAll Photos Tagged CDC
This negative-stained transmission electron micrograph (TEM) depicts the ultrastructural details of a number of influenza virus particles, or “virions”. A member of the taxonomic family Orthomyxoviridae, the influenza virus is a single-stranded RNA organism.
The flu is a contagious respiratory illness caused by influenza viruses. It can cause mild to severe illness, and at times can lead to death. The best way to prevent this illness is by getting a flu vaccination each fall.
Every year in the United States, on average:
- 5% to 20% of the population gets the flu
- more than 200,000 people are hospitalized from flu complications, and
- about 36,000 people die from flu. Some people, such as older people, young children, and people with certain health conditions, are at high risk for serious flu complications.
Influenza A and B are the two types of influenza viruses that cause epidemic human disease. Influenza A viruses are further categorized into subtypes on the basis of two surface antigens: hemagglutinin and neuraminidase. Influenza B viruses are not categorized into subtypes. Since 1977, influenza A (H1N1) viruses, influenza A (H3N2) viruses, and influenza B viruses have been in global circulation. In 2001, influenza A (H1N2) viruses that probably emerged after genetic reassortment between human A (H3N2) and A (H1N1) viruses began circulating widely. Both influenza A and B viruses are further separated into groups on the basis of antigenic characteristics. New influenza virus variants result from frequent antigenic change (i.e., antigenic drift) resulting from point mutations that occur during viral replication. Influenza B viruses undergo antigenic drift less rapidly than influenza A viruses.
For more public health images, visit the Public Health Image Library at: phil.cdc.gov/
This Centers for Disease Control microbiologist was shown here delivering tissue culture specimens into a microtiter plate using an instrument know as a pipetter. The culture samples were to be tested for the presence of the influenza virus.
The presence or absence of influenza virus would be determined by using an agglutination test. If it involved the agglutination, or clumping of red blood cells (RBCs), the phenomenon is known as hemoagglutination.
Diagnostic tests available for influenza include viral culture, serology, rapid antigen testing, polymerase chain reaction (PCR), and immunofluorescence assays. Sensitivity and specificity of any test for influenza might vary by the laboratory that performs the test, the type of test used, and the type of specimen tested. Among respiratory specimens for viral isolation or rapid detection, nasopharyngeal specimens are typically more effective than throat swab specimens. As with any diagnostic test, results should be evaluated in the context of other clinical and epidemiologic information available to health-care providers.
For more public health images, visit the Public Health Image Library at: phil.cdc.gov/
CDC Melbourne - Werribee #103 Scania L94UB, Volgren "CR228L" seen at Werribee Station on Route 443 Werribee via Greaves Street
This 1968 photograph depicted Penny Gentry, a Centers for Disease Control laboratorian, as she was inoculating 10-day-old embryonated chicken eggs with specimens that were suspected of containing influenza virus.
After inoculation, the culture was incubated for two to three days, in order to facilitate the multiplication of suspected virus particles. If a virus multiplies, it is then identified by using a serological procedure to determine the influenza type.
Diagnostic tests available for influenza include viral culture, serology, rapid antigen testing, polymerase chain reaction (PCR), and immunofluorescence assays. Sensitivity and specificity of any test for influenza might vary by the laboratory that performs the test, the type of test used, and the type of specimen tested. Among respiratory specimens for viral isolation or rapid detection, nasopharyngeal specimens are typically more effective than throat swab specimens. As with any diagnostic test, results should be evaluated in the context of other clinical and epidemiologic information available to health-care providers.
For more public health images, visit the Public Health Image Library at: phil.cdc.gov/
CDC Melbourne - Oakleigh #8 Volvo B10BLE, Volgren "CR222L" seen at Chadstone Shopping Centre on Route 623 Glen Waverley Railway Station
CDC Melbourne - Werribee #103 Scania L94UB, Volgren "CR228L" seen at Werribee Station on Route 443 Werribee via Greaves Street