A superinfection is when a second infectious disease is grafted onto an infectious disease. While virologists use the term "superinfection" only when this second disease is triggered by a very similar pathogen - for example, hepatitis B and subsequent hepatitis D - it is often referred to as superinfection, when the first disease is from viruses, the second caused by bacteria (as in "abducted bronchitis").
Use of the term "superinfection"
Actually, the technical term for secondary infection. Even if the first disease is not caused by an infectious agent, but by another cause of illness such as diabetes or atopic dermatitis, and then bacteria come into play, the term superinfection is used.
Where can a superinfection occur?
The best known superinfection is the bronchitis. This refers to a virus-induced influenza infection, which first leads to sore throats, coughing, runny nose and bronchitis and then, in a second phase, to purulent bronchitis. Due to the viruses, the mucous membranes of the nose and bronchi are already sore and irritated, so that bacteria can more easily fix and multiply.
Signs of a superinfection
Often you can already feel after a few days whether the immune system can deal well with the common cold virus and cough and runny nose quickly evaporate - or if the cold becomes chewy, the feeling of sickness again amplified, the exhaustion exhausting and maybe even productive: All that are signs of a bacterial superinfection.
Other superinfections are not as common, but can take a dramatic course. Thus, a long-standing diabetes leads to poor circulation of the body periphery and nerve endings. This can lead to the development of a diabetic foot, from which skin injuries heal only very slowly due to poor circulation.
Follow a Superinfelktion
When a diabetic skin lesion becomes infected with bacteria, the healing process can become so severely disrupted and the infection spreads so massively that it may even require surgery or, in the worst case, amputation. Even in atopic dermatitis, the skin environment is disturbed and especially in acute episodes are scratched, weeping skin prone to colonization with diseased bacteria or fungi. Luckily, the "real" superinfections rarely occur.
In order to get hepatitis D, you have to have previously been infected with hepatitis B virus - only then can hepatitis D virus survive in the body and multiply.
Infection with HIV causes a superinfection if a patient who has been infected with HIV type A, for example, later also becomes infected with type B HIV.