Our scalps are also prone to infections as any part of our bodies. There are many different types of infectious agents that can lead to this kind of infection. Bacterial and fungal infections are the most common types of scalp infections. In many cases we have increased risk getting scalp infections. There are many factors which can increase our risk to get scalp infections such as perspiration, harsh hair treatments, overactive oil glands and unwashed hair.  When some infectious agent such as fungi, bacteria or viruses infects the skin on our head, then we have a scalp infection. These kinds of infections does not happen to the skin on our faces. This is one of the most common types of infections. When we suffer from this condition, then we can get some adverse effects such as formation of sores or even we can loss our hair. The aesthetic factor can lead to psychological repercussions.
It is really important for our health to understand the real reason for the scalp infection. Viruses, fungi and bacteria are abundant in and out of our bodies and they are dispersed throughout the environment. Our skin is a physical barrier. It has a lot of mechanisms which can help us to avoid the infection. The impairment of our immune system, exposure to pathogenic organisms (organisms that cause diseases) and any derangement of our skin can increase our chances of getting an infection. In the most cases the scalp infections are caused by microbes that occur on our skin in natural way. If you have healthy skin, then these microbes are not making you some kind of problem but if you have a disturbance in your immune system or in the skin, then this can easily cause scalp infection. There are some risk factors that can increase your risk of getting scalp infection such as
- Long – term use of corticosteroid creams or oral antibiotics 
- Damage to the scalp from electromagnetic, chemical or mechanical injury. This may include heat damage and surgery to the scalp such as with the hair transplants.
- Irritation of the skin or an allergic reaction due to use of hair dyes or chemical hair straighteners 
- Excessive scratching of the scalp for any reason. This may include poor hygiene, nervous itching and hair extensions. The profuse perspiration when the sweat cannot escape can cause you skin irritation and itching. 
- Pre-existing skin diseases affecting the scalp like seborrheic dermatitis, scalp acne or scalp psoriasis.
- Exposure to people or pets which have an infection. Also microbes can be transmitted by inanimate objects.
- People with a weakened immune system like in poorly managed diabetes and HIV/AIDS.
Types of scalp infections: There are some types of scalp infections which can be categorized by the microbe which is a reason for the infection. There are viral, bacterial and fungal scalp infections.
- Fungal scalp infections: One of the most common microorganisms that lead to scalp infections are fungi. But you should know that not every kind of fungi can lead to scalp infections. In some cases when there is overgrowth of fungi, then this leads to inflammation. The most common types of fungi are yeasts and dermatophytes. Yeasts usually affect the cavities such as vagina and mouth. Dermatophytes has specialized enzymes that digest keratin which is a skin protein and they have a predilection for skin. 
- Bacterial scalp infections: The most prevalent microbes in and out of the body are bacteria. Also they are teeming in our environment. In some cases bacteria occur in natural way on our skin and in this case they are referred as normal skin flora. But also there are some cases in which they are a reason for serious diseases. But also there are some cases when naturally occurring and harmless bacteria are becoming pathogenic bacteria which mean that they go deeper in our skin and we should threat them throughout all life. 
- Viral skin infections: You should know that viruses are not common reason for the scalp infections. When we have a systemic infection, then this can lead to skin lesions.
Above are some of the types of scalp infection.
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