It was once the case that a sneeze warranted a polite “bless you”. These days strangers will spring away from you and hiss. Never mind that sneezing is not a symptom of the dreaded coronavirus, it is simply not acceptable to be seen in public with anything that might point to a health ailment.

But it is warming up for spring; the season of hay fever is upon us, and for 13 million Britons, that means itchy eyes, a wheezy cough and a runny nose. In Japan - an ever innovative nation - it's the same story, and in response city-dwellers have taken to wearing badges that mark their condition when out in public.

The nifty pins display messages such as “I have hay fever,” “I have asthma” and “This cough isn’t contagious.” One store owner, Miwa Makino, told The Japan Times: “Even when I’m wearing a face mask, I’m worried about what other people are thinking and I feel sorry.”

The badges have reportedly been flying off the shelves since February when the coronavirus first made itself known - and theses purchases are typical of a culture which puts politeness front and centre, as our local expert Danielle Demetriou has explored in the past.

Of the current atmosphere there now, she says: “Living with my family in central Tokyo, there is a sense of a new normal settling on daily life, as is most likely the case in many other countries impacted by coronavirus. Schools have temporarily closed (a move regarded by many as more gesture than necessity). Major attractions such as Tokyo Disneyland and national museums are shut, festivals have been cancelled, and domestic flights cut back. Plus, armies of white facemasks have become the status quo view in streets, offices, shops and public transport.

“Yet there are also some refreshing silver linings, particularly for visitors: namely, less crowds. A drop in inbound tourism, fuelled by the cancellation of group tours from China in particular, has left many popular destinations unusually quiet. Buses are no longer dropping off hordes of tourists for shopping sprees at the high-end stores of Ginza. Reservations at tricky-to-book restaurants are easier to nab. Plus, the nation’s much-loved cherry blossoms will still stubbornly bloom for all to see, regardless of the Covid-19 situation, most likely with fewer crowds.”

Hay fever or coronavirus – how can I tell the difference?

It may seem early, but some some unlucky hay fever sufferers can be affected with year-round symptoms. And while we often just think of pollen in flowers, it’s also in grass, trees and weeds, and there are different seasons for each. Tree pollen is March to mid-May; grass pollen is mid-May to July, and weed pollen is from the end of June to September.

In the Netherlands, people are currently being warned that unusually warm weather could cause ash and birch trees to flower early this season.

“Some of the hay fever symptoms are similar to complaints which are found in COVID-19 patients,” researchers at the Leiden teaching hospital told Dutch News. “An allergic reaction could worry hay fever sufferers and people close to them, so they need to be aware of this.”

Whether your symptoms are likely to be a result of hay fever, the common cold, or worse, the coronavirus, is mainly down to itchiness. Hay fever is an allergic reaction – your immune system gets the wrong message, and overreacts to non-harmful pollen or fungal spores, releasing histamine to prevent the spread of the “infection”, causing watering eyes and a running nose.

The symptoms of a virus, on the other hand, often includes a fever, which is unlikely to be present in the case of a pollen allergy.

See more about the symptoms of coronavirus here. And stay safe.