Uptick in 'off-season' chickenpox, herpes cases leaves patients, doctors stumped in Kolkata

Kolkata: An 'untimely' spread of chickenpox and herpes - both triggered by the varicella zoster virus - has left patients and doctors in Kolkata stumped this winter. It's usually during the February-April period that chickenpox cases are more frequently reported. But scores have been suffering from it since mid-December.

Though unusual, doctors said a chickenpox spread is possible at any time of the year since the virus is not weather-dependent. There is, however, no particular season or period for herpes, which is triggered by a dormant varicella virus that silently nestles itself at the spinal cord nerve after a bout of chickenpox. "When the immunity gets low, the virus becomes active and manifests as herpes infection," said RTIICS intensivist Sauren Panja. It has three phases - pre-eruptive, acute, and chronic or post herpetic neuralgia.

While chickenpox spreads through droplet, herpes can be transmitted through physical contact.

Experts pointed out that the first exposure to the virus should always trigger chickenpox, which has not been happening in many cases this time. "Once an individual gets chickenpox, she or he develops immunity, which prevents a second attack. So, a second exposure often leads to herpes. But I have received several herpes patients who have never had chickenpox," said an internal medicine consultant.

Earlier, it was believed that chickenpox never strikes a second time since the first attack ensures life-long immunity. "But in recent years, that perception has changed and second attacks have been frequently reported. But they are usually mild," said Panja.

A general drop in immunity could be the reason, said internal medicine consultant Arindam Biswas. "While it's not unusual for chronic liver disease or diabetes patients to get herpes due to compromised immunity, this year, we have come across perfectly healthy individuals who were affected on first exposure to the virus. Chickenpox cases are more frequently reported in spring, but it has suddenly proliferated at the height of winter this time. It is unusual, but since it's a viral infection, chickenpox may strike any time," he said.