The varicella zoster virus

Chickenpox and shingles can be serious

Chick­en­pox is a dis­ease caused by the vari­cel­la zoster virus. It used to be called the her­pes zoster virus because it is relat­ed to oth­er her­pesvirus­es. A case of chick­en­pox starts off as a flu-like ill­ness, fol­lowed by an itchy rash. Before the devel­op­ment of the vari­cel­la vac­cine, near­ly every­one even­tu­al­ly caught chick­en­pox. In the Unit­ed States, rough­ly 10,000 peo­ple per year were hos­pi­tal­ized because of chick­en­pox, and there were rough­ly 100 deaths per year.

Chick­en­pox in chil­dren is usu­al­ly a rel­a­tive­ly mild flu-like ill­ness with an itchy rash that lasts for about a week. But in some cas­es, it can lead to seri­ous or even dead­ly com­pli­ca­tions:

Chick­en­pox used to be a child­hood ill­ness. It is more dan­ger­ous if it occurs in an adult.

A case of chick­en­pox is par­tic­u­lar­ly dan­ger­ous dur­ing preg­nan­cy:

Once you have had a vari­cel­la infec­tion, the virus is with you for life. Just like the her­pesvirus­es that cause cold sores, the vari­cel­la zoster virus can flare up again, caus­ing a painful con­di­tion called shin­gles. A case of shin­gles gen­er­al­ly affects the area of skin served by a sin­gle nerve. An out­break that involves an eye could lead to blind­ness in that eye. The shin­gles out­break can dam­age the nerve, lead­ing to lin­ger­ing, often severe pain. This prob­lem is called pos­ther­pet­ic neu­ral­gia. For­tu­nate­ly, we now have a vac­cine to pre­vent shin­gles out­breaks. It is basi­cal­ly a boost­er of the chick­en­pox vac­cine.

Pho­to by NIAID