Cold sores (herpes labialis, herpes simplex)

Cold sores, medi­cal­ly known as her­pes labia­lis, is one of the most com­mon viral infec­tions in humans. Around 90 per­cent of the popu­la­ti­on are infec­ted with the her­pes sim­plex virus type 1, with recur­ring visi­ble out­breaks occur­ring in around 30 to 40 per­cent. The initi­al infec­tion usual­ly occurs in child­hood through dro­p­let infec­tion or direct cont­act, for exam­p­le through kis­sing. In many cases, the initi­al infec­tion goes unno­ti­ced; in some cases, mouth sores with pain­ful blis­ters in the enti­re oral cavi­ty and fever occur. After the initi­al infec­tion, the virus retre­ats along the ner­ve tracts to the ner­ve nodes in the head area, whe­re it remains in a dor­mant sta­te for life. The virus can be reac­ti­va­ted under cer­tain cir­cum­s­tances: a wea­k­en­ed immu­ne sys­tem due to a cold or other infec­tions, stress, exhaus­ti­on, inten­se UV radia­ti­on, hor­mo­n­al fluc­tua­tions during mens­trua­ti­on, fever or minor inju­ries in the lip area. An out­break of cold sores occurs in seve­ral pha­ses. Initi­al­ly, tho­se affec­ted feel a ting­ling, bur­ning or tight sen­sa­ti­on on the lip. Then small blis­ters fil­led with clear flu­id form on a red­den­ed back­ground, usual­ly at the tran­si­ti­on bet­ween the red of the lip and the skin. The blis­ters are pain­ful and can itch. After a few days they burst and a yel­lo­wish crust forms. Heal­ing takes around seven to ten days. The dise­a­se is high­ly con­ta­gious during the vesic­le pha­se. The dia­gno­sis is usual­ly made cli­ni­cal­ly. In unclear cases, the virus can be detec­ted from the con­tents of the blis­ters. A cau­sal cure is not pos­si­ble as the virus remains in the body for life. Anti­vi­ral creams with acy­clo­vir or pen­ci­clo­vir should be appli­ed at the first signs and can miti­ga­te the cour­se of the dise­a­se. Anti­vi­ral tablets can be taken in the event of fre­quent recur­ren­ces. During an acti­ve out­break, kis­sing and sha­ring dis­hes should be avo­ided. Sun pro­tec­tion for the lips can pre­vent UV-rela­ted outbreaks.