What is influenza A virus and why is it dangerous?<\/h2>\n
Influenza A virus belongs to the Orthomyxoviridae family. Its characteristic feature is the presence of surface proteins:<\/p>\n
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hemagglutinin (H)<\/p>\n<\/li>\n
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neuraminidase (N)<\/p>\n<\/li>\n<\/ul>\n
The combination of these proteins forms strains, such as H1N1 or H3N2. It is the changes in these structures that allow the virus to evade the immune response.<\/p>\n
Influenza A is dangerous because:<\/p>\n
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can be transmitted from animals to humans<\/p>\n<\/li>\n
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causes a more severe course in risk groups<\/p>\n<\/li>\n
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more often causes complications<\/p>\n<\/li>\n
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spreads quickly in groups<\/p>\n<\/li>\n<\/ul>\n
Symptoms of influenza A: how to recognize the infection<\/h2>\n
Symptoms of influenza A usually come on suddenly. A person may feel fine in the morning, but within a few hours they may have a high fever and severe weakness.<\/p>\n
The most common symptoms of influenza A:<\/p>\n
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temperature 38\u201340\u00b0C<\/p>\n<\/li>\n
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severe headache<\/p>\n<\/li>\n
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muscle aches<\/p>\n<\/li>\n
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chills<\/p>\n<\/li>\n
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dry cough<\/p>\n<\/li>\n
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sore throat<\/p>\n<\/li>\n
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pronounced weakness<\/p>\n<\/li>\n<\/ul>\n
Children may experience vomiting and diarrhea.<\/p>\n
How is influenza A different from a cold?<\/h2>\n
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\n \nIndicator<\/th>\n Influenza A<\/th>\n Common cold<\/th>\n<\/tr>\n<\/thead>\n \n Beginning<\/td>\n Abrupt<\/td>\n Gradual<\/td>\n<\/tr>\n \n Temperature<\/td>\n High<\/td>\n Low or absent<\/td>\n<\/tr>\n \n Muscle pain<\/td>\n Expressed<\/td>\n Rarely<\/td>\n<\/tr>\n \n Weakness<\/td>\n Strong<\/td>\n Moderate<\/td>\n<\/tr>\n \n Complication<\/td>\n Possible<\/td>\n Liquid<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n<\/div>\n This comparison helps to understand why influenza A requires more careful attention.<\/p>\n
How is influenza A transmitted?<\/h2>\n
Influenza A virus is transmitted:<\/p>\n
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airborne<\/p>\n<\/li>\n
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through close contact<\/p>\n<\/li>\n
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through contaminated surfaces<\/p>\n<\/li>\n<\/ul>\n
The incubation period is 1\u20134 days. A person may be contagious even before symptoms appear.<\/p>\n
Diagnosis of influenza A: when a test is needed<\/h2>\n
During periods of high incidence, the clinical picture may be sufficient to establish a preliminary diagnosis. However, laboratory diagnosis of influenza A is necessary:<\/p>\n
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in severe cases<\/p>\n<\/li>\n
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in pregnant women<\/p>\n<\/li>\n
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in young children<\/p>\n<\/li>\n
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in patients with chronic diseases<\/p>\n<\/li>\n
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if complications are suspected<\/p>\n<\/li>\n<\/ul>\n
Diagnostic methods:<\/p>\n
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![\"laboratory](\"https:\/\/medilab.km.ua\/wp-content\/uploads\/2026\/02\/front-view-doctor-with-medical-mask-holding-up-vacutainers.jpg\")
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