嬰兒玫瑰疹 Roseola Infantum

又名猝發疹 ─ Exanthema Subitum

玫瑰疹是一種最常見的嬰幼兒病毒感染疾病，整年都可能發生，但在春秋兩季較為明顯增多，主要為皰疹病毒第6型及第7型最常見。

玫瑰疹是一種常見的嬰幼兒良性感染疾病，玫瑰疹不如麻疹、德國麻疹、水痘等疾病容易感染，很少有併發症或後遺症，多半發生在兩歲以下，常見的是六個月到一歲半大的嬰幼兒最容易感染，但是小至兩、三個月，大至兩、三歲的嬰幼兒也都有可能會得到玫瑰疹。

嬰幼兒感染玫瑰疹疾病，最常見的是出現發高燒3或4天，溫度可高至攝氏39度至40度。當高燒的時候，除了小臉頰會燒得紅紅的以外，也可能有輕微咳嗽、喉嚨紅腫、流鼻涕等上呼吸道感染症狀，頸部的淋巴腺也可能腫大，有的嬰兒也可能會出現腹瀉狀況，但大致來說嬰兒的胃口、活動力也都還好。

玫瑰疹最大的特性就是當出現玫瑰紅似的細小斑丘疹時，往往也就是高燒漸退，玫瑰疹疾病快到尾聲的預告，細小斑丘疹的特徵為不會癢，大約一到三天內細小斑丘疹會自動消失，身體上不會像得麻疹一樣有任何色素沉著或脫屑等現象。

感染玫瑰疹時最常發生的困擾，即嬰幼兒因高燒所引起的四肢突發性抽筋現象，又稱為熱性痙攣。由於此年齡層(6個月至5歲)的嬰幼兒因為腦細胞還沒完整發育，發高燒的時候，容易引起腦細胞之間亂放電的現象。腦細胞之間亂放電，就會引起嬰幼兒四肢突發性的抽筋或對稱性手腳抽動，多半持續2－3 分鐘，父母們常會為此嚇得不知所措。

四肢突發性抽筋現象，又稱熱性痙攣，是嬰幼兒因高燒合併神經症狀，為良性症狀，熱性痙攣對嬰幼兒不會有任何影響或後遺症，也不會進一步發生其他併發症，父母們不用過度擔心。

Roseola infantum

Roseola infantum is a common, mild, viral infection that can cause a temperature and rash in babies and young children.

It is caused by a virus from the herpes group, but it does not cause other herpes infections like cold sores. In the past, roseola was sometimes referred to as 'baby measles'.

Roseola usually lasts around four days and almost never requires any medical treatment. Most symptoms are so mild that parents do not even realise their child is infected with the virus.

Roseola commonly affects children aged between six months and two years, and 95% of children have been infected with it by the age of two.

Roseola is contagious before the symptoms appear, so it is difficult to prevent its spread to others.

Signs and symptoms

If your child has roseola, they may have a sudden high temperature, which usually lasts between three to five days. Occasionally, a raised, red rash can develop when your child’s temperature returns to normal.

It appears on the body and spreads to the arms and legs; it is rarely seen on the face. The rash generally lasts for two days and turns white (blanches) when pressed.

Some children get a high temperature but no rash. Rarely, the temperature spikes quite suddenly and can lead to a febrile convulsion (a seizure, or fit). While this is distressing for parents to witness, it is not usually serious.

How is roseola spread?

Roseola is contagious, meaning it can be spread from one person to another.

It is spread by the fluids that are coughed or sneezed into the air.

Children with roseola can only spread the infection before the fever and/or rash occur. Once your child has symptoms, they are no longer contagious.

There is no known way to prevent the spread of roseola and there is no vaccine. Thorough hand hygiene is the best way to help reduce the spread of the virus.

Care at home

Most of the time, roseola does not need any professional medical treatment.

Paracetamol can be used if your child has a high temperature and seems uncomfortable or irritable.

Offer your child plenty of fluids (water, breastmilk or formula) to keep them well hydrated during a fever.

Antibiotics are not given because antibiotics do not treat viruses.

When to see a doctor

• You should see your GP if your child:

• is lethargic (very sleepy, hard to wake)

• has fewer wet nappies than usual

• your child has a fever that does not get better after 48 hours has a convulsion (a fit) that lasts less than five minutes

You should call an ambulance immediately if:

l your child has a convulsion that lasts more than five minutes

l your child does not wake up after a convulsion

l If your child is unwell with a fever and a skin rash (small bright red spots or purple spots or unexplained bruises) that does not turn to skin-colour (blanch) when you press on it, this may be a sign of meningococcal infection

Key points to remember

Roseola is a very common, mild infection, usually affecting children between the ages of six months and two years.

Roseola may cause a sudden, high temperature followed by a raised, red rash that lasts for a few days.

Give plenty of fluids to prevent dehydration, and paracetamol may be used to help make your child more comfortable.

Roseola is contagious, but only before the symptoms appear.