People newly diagnosed with cancer, particularly blood cancers, and those treated with chemotherapy have a greater risk of developing shingles, according to a new study in the Journal of Infectious Diseases.

The findings may help guide efforts to prevent the often painful skin condition in cancer patients through the use of new vaccines.

The large prospective study expands on previous research by examining the risk of shingles before and after a new cancer diagnosis and across a range of cancer types among approximately 240,000 adults in Australia from 2006 to 2015.

Shingles, or herpes zoster, is caused by the varicella zoster virus, the same virus that causes chickenpox.

Shingles develops when the virus, which remains dormant in the body, reactivates later in life.

Nearly one in three people in the U.S. will develop shingles in their lifetime, and there are an estimated 1 million cases in the country each year, according to the U.S. Centres for Disease Control and Prevention.

In the study, researchers found that, overall, a cancer diagnosis of any kind was associated with about a 40 percent increase in risk for developing shingles compared to the risk in someone without cancer.

Patients with a blood-related, or haematological, cancer diagnosis had a more than three-fold higher risk of developing shingles than people without cancer.

Individuals with a diagnosis of cancer related to a solid tumour, such as cancer located in the lung, breast, prostate or other organ, had a 30 percent higher shingles risk compared to someone with no cancer.

The new analysis in the Journal of Infectious Diseases also found that the higher risk for shingles among patients with blood cancers was present in the two years before their cancer diagnosis, according to the study's first author, Jiahui Qian, MPH, of the University of New South Wales in Sydney, Australia.

However, for patients with solid tumours, the higher risk of developing shingles appeared to be largely associated with receiving chemotherapy after their diagnosis, rather than with the cancer itself.

In examining the higher risk of shingles in cancer patients, few previous studies have separated the risk for shingles associated with a patient's cancer from the risk associated with chemotherapy.

"These findings have important implications in view of recent advances in development of zoster vaccines," wrote Kosuke Kawai, ScD, of Boston Children's Hospital and Harvard Medical School and Barbara P. Yawn, MD, MsC, of the University of Minnesota, in a related editorial commentary that appears with the new study in the Journal of Infectious Diseases. The commentary authors were not involved in the research.

A new shingles vaccine approved for use in the U.S. in 2017 does not use a live form of the virus and is likely to be safe in people with compromised immune systems, such as those on chemotherapy.

The vaccine is not yet recommended for these individuals in the U.S., as public health officials await more data on the vaccine's use in such patients.

Another new shingles vaccine that uses an inactivated form of the virus is also in development.

These advances suggest that vaccination holds great promise as a strategy to prevent shingles and its complications in cancer patients, the commentary and study authors both noted.

Source: Infectious Diseases Society of America