How long are you contagious?
If a child falls ill with scarlet fever, many parents ask themselves over what period of time the danger of infection exists and what one should pay attention to in order to reduce it. The length of the infection period depends largely on the beginning of the medical therapy. If an antibiotic therapy with penicillin is started immediately for scarlet fever, there is usually no acute danger of infection after 24 hours.
Even if there is a significant reduction in symptoms and the affected person feels better quickly, it is important, especially in the case of children, to ensure that they stay at home for a few more days and get well. An antibiotic therapy, as well as a too fast return to kindergarten and school, accompanied by stress, can lead to an additional weakening of the immune system. In this context, complications or secondary diseases may occur that further delay recovery.
If no antibiotic is administered, the affected persons are infectious for another 3 weeks and there is a risk of infection. Particularly dangerous in scarlet fever is the risk of infection before the first typical symptoms appear. In contrast to many other infectious diseases, scarlet fever is not only contagious when the first symptoms such as sore throat or skin rashes manifest themselves, but already in advance, when the affected person is still feeling well and is recovering.
It is precisely during this so-called incubation period, when the affected persons are already infected by the bacteria but the infection is not yet far advanced, that the greatest risk of infection exists. The incubation period can last 2 – 4 days and be completely symptom-free for the sick. Only after this time, the bacteria have properly nested in the mucous membranes of the diseased and form the scarlet toxin (toxin), which in turn leads to the typical skin rash accompanied by fever, sore throat and fatigue.
The scarlet fever pathogen Streptococcus Pyogenes is able to form toxins, the so-called toxins, of which three different ones are known so far. Only if the respective streptococcus species forms one of these toxins, scarlet fever will occur.After the illness is over, the person is protected against this one toxin, but not against the other toxins. An infection with a pathogen that produces one of the other toxins is therefore still possible.
Thus, a single scarlet fever infection does not protect against another. As a rule, the risk of infection with scarlet fever usually begins 2 – 4 days before the onset of the first symptoms typical of the disease. This means that a high risk of infection can already emanate from those affected during this time.
According to medical guidelines, scarlet fever should always be treated with antibiotic therapy. Penicillin is prescribed as an antibiotic, which should be taken for 7 – 10 days as a rule. It is important to take it consistently over the prescribed period, even if the child already feels much better and no longer shows any symptoms.
If the antibiotic therapy is started quickly, there is usually no more danger of infection after 1 – 2 days. If scarlet fever is not treated with an antibiotic in accordance with current guidelines, not only does the risk of infection increase, but also the period of time during which those affected are infectious. Without appropriate antibiotic therapy, the risk of infection persists for a total of up to 3 weeks.
The typical symptoms of scarlet fever, sore throat and skin rash also last longer and those affected feel much worse and are very weakened. Particularly in adults, the symptoms can last for several weeks or even several months without the use of adequate antibiotic therapy.
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