Arab News Japan

TOKYO: The term ‘Moderna arm’ is spreading in Japan to describe cases where characteristic side effects appear a few days after vaccination with Moderna’s coronavirus vaccine.

It’s reported that a person from Japan’s Self-Defense Forces, who was vaccinated with the Moderna product, discovered the condition in which the injected arm turns red for several days after the first vaccination. According to reports issued by a Health Ministry Research Team Investigation, it is more common in women.

Japanese local media reported that this side effect is found in 2.6% of women in their 20s, 8.1% of women in their 30s, and 7.8% of women in their 40s.

The Ministry said that the cause remains unknown, though food allergies and asthma have been ruled out.  Additionally, 78% experienced a light fever the day following the second shot of Moderna vaccine, and 20% the day after. The fever usually disappeared after that. Some 35% of respondents took days off from work after the second shot, and nearly 15% were absent the day after the first shot.

On the other hand, people older than 40 tended to experience only arm pain. Other symptoms were more common in younger people comparable to results seen with Pfizer’s vaccine.  Women tended to have more side-effects than men generally, as was also true with Pfizer.

People who had been infected with the new coronavirus variants were more likely to experience fever and malaise after the first vaccination than those who had never been infected.  Experts have suggested that if a person has basal immunity due to infection, they will experience a side reaction even with the first vaccination.  In other words, people with a strong side-effect reaction after the first shot may already have experienced coronavirus infection.