Alphaviruses.
Alphaviruses remain important emerging mosquito-borne, zoonotic pathogens that cause both localized human outbreaks and epizootics (e.g., Venezuelan equine encephalitis) and large human epidemics (e.g., Chikungunya). Alphaviruses are globally dispersed, and each continent has humans at risk from one or more of these arthropod-borne viruses (arboviruses). Symptoms of human alphaviral disease range from frank, severe encephalitis (e.g., eastern and western equine encephalitis) to polyarthritis (e.g., Ross River). Diagnostic techniques to identify human alphaviral infections have changed dramatically with the development and implementation of standardized nucleic acid amplification tests (NAAT). The NAAT is rapidly replacing virus isolation and typing using indirect fluorescent antibody (IFA) assay with monoclonal antibodies (MAbs) as the preferred method of virus identification. The older techniques still have value, however, since alphaviral growth in cell culture is rapid, and IFA with MAbs is inexpensive. This chapter provides detailed, standardized protocols for the identification of alphaviruses from clinical specimens and the serological characterization of human infection-immune sera. Both laboratory approaches are needed to identify and confirm human infections with these agents.
Arboviral Diseases Branch, Division of Vector-Borne Infectious Diseases, U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, Public Health Service, Fort Collins, CO, USA.
A M
AM
Powers
John T
JT
Roehrig
D000524:Alphavirus / Q000276:immunology* / Q000302:isolation & purification*; D018354:Alphavirus Infections / Q000175:diagnosis / Q000821:virology*; D000818:Animals; D000911:Antibodies, Monoclonal; D000956:Antigens, Viral / Q000032:analysis; D009033:Culicidae / Q000821:virology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods; D006801:Humans; D007106:Immune Sera; D021141:Nucleic Acid Amplification Techniques; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
D000911:Antibodies, Monoclonal; D000956:Antigens, Viral; D007106:Immune Sera