Antibiotics and influenza

Antibiotics are basically only effective against bacteria, so they cannot fight the flu viruses. However, since the virus infection favors further, additional infections caused by bacteria (so-called bacterial superinfections) due to the weakening of the immune system, antibiotics can still be useful. This is because the inflammations caused by bacteria in the lungs or heart muscle, among other things, often have more serious consequences than the flu itself and require further treatment even after the actual virus infection has healed.

Elderly patients and people with chronic heart–lung diseases, immune deficiencies or other serious underlying diseases are particularly at risk. Since antibiotics should only be used moderately and as specifically as possible due to the threatening development of resistance, the basic administration of antibiotics is definitely not advisable in the case of influenza. The decision for or against an additional antibiotic therapy is made individually depending on existing risk factors, general condition and severity of the infection.

Amantadine prevents the release of genetic material from viruses in a newly infected host cell. It blocks a protein, the so-called M2 protein, which is located in the envelope of the virus. Due to the blockage, the virus can no longer initiate the release of its genetic material, the RNA, and thus cannot reproduce.

Amantadine is only effective with influenza viruses of type A and has many, sometimes serious side effects such as diarrhoea, depression and rarely even epileptic seizures. Many influenza viruses are now also resistant to amantadine, so it is rarely used. The most important drugs against influenza, such as oseltamivir (Tamiflu), belong to the new group of neuraminidase inhibitors.

Neuraminidase inhibitors prevent new viruses from being released from infected cells by blocking the protein neuraminidase. The newly produced viruses thus remain attached to the infected cell and cannot infect other cells.Again, treatment must be initiated within 48 hours of the onset of symptoms to ensure sufficient effect. If treatment is started within one day after the first symptoms appear, the duration of the flu illness can be shortened by up to 40%.

In addition, complications due to bacterial superinfection can be prevented in more than half of the treated patients. The neuraminidase inhibitors can also be given prophylactically (as a precaution) to people who have been exposed to the flu virus (exposure) and belong to the risk group or cannot be vaccinated due to an egg protein allergy. Bacterial superinfections can be treated with antibiotics; since the pathogens causing the flu are viruses, the flu itself cannot be treated with antibiotics.