The season of itchy eyes, runny noses and sneezing is around the corner again.
Forecasts indicate that the levels this year of cedar and cypress pollen — the two most common causes of hay fever in Japan — are expected to be far higher than last year in many parts of the country.
While this is sure to come as bad news for the increasing number of people suffering from pollen allergy, doctors are urging sufferers to seek proper diagnosis so they can be treated effectively.
Norio Sahashi, chairman of the Palaeontological Society of Japan and director of the Association of Pollen Information, said the high temperatures, low rainfall and abundant sunshine last summer were conducive to producing abundant cedar and cypress spores.
Sahashi, who travels to different parts of the country to check cedar and cypress trees, said pollen levels in most regions this year are likely to be around double the average over the past decade.
“But they won’t surpass the levels seen in 2005,” when extremely high concentrations of cedar and cypress pollen were recorded, Sahashi said.
He said northeastern, eastern, central and some parts of western Japan will probably see levels twice as bad as usual, while the Chugoku region in western Honshu and Shikoku will have an average season. Kyushu could catch a break and have less pollen than normal.
Cedar dissemination, usually from early February to early May, and cypress pollen, from early March to mid-May, should commence within the normal range or could start slightly later this year, Sahashi said.
To brace for the hay fever season, doctors are recommending early preparations to control and ease symptoms.
People can take simple preventive measures such as wearing a mask when outdoors as well as gargling and washing one’s face after going outside, according to the Health, Labor and Welfare Ministry website.
Commonly available medications to ease symptoms include antihistamines, decongestants and nasal sprays.
Hay fever can also be suppressed over the longer term by immunotherapy injections that expose recipients to low levels of allergens so their bodies can get accustomed by the time the season commences.
But immunotherapy is often accompanied by side effects and is more effective when the treatment lasts several years, according to Minoru Goto, an allergist who teaches at Nippon Medical School’s otorhinolaryngology department.
Goto stressed that as with any other illnesses, it is “important to get tested for hay fever to pinpoint the cause so appropriate treatment can be given.”
Simply experiencing allergic symptoms in spring doesn’t necessarily imply a cedar or cypress pollen allergy because the season abounds with other allergens, including alder pollen, while household dust can cause problems year-round.
There are several ways to test for allergies, including blood tests, skin tests and infusion tests, which involve patients actually consuming allergens to test for a reaction.
While it usually takes about a week to get the results of blood tests, Goto said there is a new simple testing device being used on a trial basis in which a few drops of blood from a fingertip can pinpoint in 20 minutes an allergy to eight common triggers, including cedar pollen and ticks.
Koichi Iwai, president of Phadia K.K., the Japanese subsidiary of a Sweden-based pharmaceutical company that specializes in allergy testing, cited data from a 2009 report on nasal allergies that showed the prevalence of pollen allergies in Japan had increased from 19.6 percent in 1998 to 29.8 percent in the following 10 years.
To meet the growing need for allergy testing, the company, which also makes the simple testing device, has developed large-scale equipment that enables clinical testing centers to conduct up to 960 regular blood tests an hour.
“There is definitely an increasing trend in terms of the prevalence of allergies in Japan and around the world, so we’re seeing more and more patients in need of allergy testing,” Jean Forcione, chief operating officer of Phadia AB.
The “largest-ever instrument in allergy testing” was developed in response to the needs of large Japanese commercial laboratories that “run an immense number of tests that are highly automated and sophisticated, and they were asking us for better solutions to further automate their laboratories,” Forcione said.