Shingles: Chickenpox packing a punch

Shingles Awareness Week 2025 is from February 24 to March 2. I was unaware that such an event existed until—you guessed it—I was diagnosed with shingles during Shingles Awareness Week! The timing is impeccable.

Thanks to getting shingles, I am reviewing what I have learned about this condition (in college-level virology and during my PHM training) in juxtaposition with my experience.

What is shingles?

Shingles is a disease caused by the Varicella Zoster Virus (VZV). The VZV contains double-stranded DNA, similar to its host (i.e., people). Its replication mechanism is similar to its host, allowing it to use the host's enzymes to multiply. As Dr Jill Hacker (of CDPH's Viral and Rickettsial Diseases Laboratory) said during one of her Virology lectures, VZV (and its cousins in the Herpesviridae family) is a "gift that keeps on giving" because once someone gets it, the virus is with him/her as long as he/she is alive.

As it happens, VZV is the same virus that causes chickenpox. I contracted chickenpox one summer in the early 1990s, a few years before the chickenpox vaccine was available in the Philippines. Since then, the VZV has been with me, sitting dormant somewhere in my central nervous system. It's been waiting patiently for the perfect time to remind me that it's still there. 

According to the CDC, the risk of getting shingles (a.k.a. herpes zoster) increases with age. People with weak immune systems due to disease (e.g., HIV, diabetes mellitus) or medication (e.g., steroids, drugs after organ transplant) are also at higher risk of getting shingles.

The good news is that people with shingles have a lower chance of spreading VZV to others than people with chickenpox. Direct contact with liquid in the rash blisters or breathing in the liquid from the rash blisters can spread the VZV to people who have not had chickenpox or the chickenpox vaccine. In contrast, people with chickenpox can spread the VZV by coughing and sneezing, in addition to direct contact with the rash blisters.

How do people know that they have shingles?

A person with shingles may start with fever, fatigue, a burning or tingly feeling on one side of the body (typically just where the affected nerve is located), and the appearance of red rashes. The rashes become blistered and filled with liquid. These blisters eventually pop open and become open sores. Then, they dry up and crust over a week or two later. People often talk of the pain associated with shingles. It's the constant burning pain and pins and needles sensation for the days when the blisters are forming and drying, and then it turns into incessant itching as the scabs dry up. The scabs and the pain resolve in about five weeks from the first symptom. Yet, scratching the blisters or the scabs is discouraged because of the risk of bacterial superinfection.

Doctors diagnose shingles by observing the appearance and location of blisters. The telltale clue is blisters occurring along a band on one side of the body. The virus follows a nerve path from the spinal cord to the skin, erupting into blisters. The tingly burning pain is caused by the virus spreading on the nerve path.

This is the timeline of my case:

Date	Symptoms, Observations
02/18/2025	I felt fatigued, and my supervisor noticed it.
02/19/2025	The right side of my forehead felt numb.
02/20/2025	A slight red rash appeared on my right forehead. I put Katinko on it, thinking that it's an insect bite.
02/21/2025	The rash grew bigger and formed a blister while I was at work. It was excruciating (burning and shooting). An area in front of my right ear was tender, and the right side of my neck was stiff and painful. I went to an urgent care centre to have it checked. The doctor assigned to me said that the rash appeared to be caused by cellulitis. An antibiotic prescription should stop it.
02/22/2025	I started taking the antibiotic the doctor had prescribed. The rash was at its most prominent and most swollen.
02/23/2025	The rash became smaller, but the pain did not subside.
02/24/2025	The rash was still getting smaller and less red, but more blisters appeared on the right side of my forehead. I was unsure if the antibiotic worked, so I went to the urgent care centre again. The doctor said that my symptoms were more consistent with shingles.
02/25/2025–03/04/2025	I started taking antiviral medication, which helped slow down the spread of the virus along the nerve path. I finished the antibiotic treatment, which helped stop the bacterial infection of the now-open and oozing blisters. My forehead was still numb, and I had stabbing headaches from time to time, but the pain in front of my ear dissipated eventually.
03/05/2025	The blisters have all scabbed over. The pain has also been reduced to numbness. There is a good chance that the numbness will disappear in a few more weeks as the nerves heal. The pain in front of my ear disappeared.

The mystery has finally been solved: Where did VZV hide after my chickenpox episode in the 1990s? It was hiding in the trigeminal nerve!

What should people do if they have shingles?

Because the primary transmission mode of shingles is contact with the liquid in the blisters, people with shingles should cover the blisters with non-adhesive pads. They should also follow their doctor's treatment plan (which may include antivirals and pain medications).

The CDC recommends that people with shingles be excused from in-person work if working with people who have not had chickenpox and are not vaccinated (e.g., newborns) or with immunocompromised people.

How do people prevent getting shingles?

The CDC recommends that adults aged 50 and older receive two doses of the shingles vaccine to prevent shingles and its complications. I wonder if younger people who have had shingles are eligible for the vaccine.