Prevention of 2009 Pandemic Influenza A/H1N1 Virus Infection by Administration of Hochuekkito, a Japanese Herbal Medicine
Dr. Donaldson et al. showed mortality from pandemic A/H1N1 2009
influenza in England.(1) In Japan, the number of infections with H1N1
virus (2) has increased rapidly since the end of August 2009, and
vaccination is not generally available. Using oseltamivir for H1NI
infection prophylaxis is not recommended because of the limited supply and
risk of emergence of oseltamivir-resistant strains.(3) In China,
traditional herbal medicines have been used to treat influenza infections
for 2000 years. Recently, these agents have been employed to treat various
diseases in Japan and have also become popular in Europe and the United
States.(4) One herbal formula, Hochuekkito (TJ-41; Tsumura, Tokyo, Japan),
is given to patients with a bacterial or viral infection or postsurgery
shock.(5) In mice infected with influenza virus, TJ-41 therapy increased
the rate and duration of survival.(6)
With approval from the institutional review board of Aisei Hospital
and the participants' written consent, we assessed the efficacy of TJ-41
in preventing influenza A infection, including H1N1 infection, in the
hospital's employees. The hospital has 358 employees, 179 of whom were
initially assigned to take 2.5 g of TJ-41 twice daily beginning on
September 7, 2009, and 179 of whom did not take TJ-41 (group 1). Fourteen
employees given TJ-41 discontinued its use after one week (group 2)
because of the bitter taste of the medication or onset of mild diarrhea,
fatigue, facial edema, or headache. By 4 weeks after treatment began, 103
employees had stopped taking TJ-41 (group 3). Sixty-two employees took TJ-
41 for 8 weeks (group 4). None of the employees given TJ-41 had any severe
or moderate adverse effects.
In the 8 weeks from September 7 to November 2, influenza A infection
confirmed by rapid diagnostic testing developed in 8 employees. The
Infectious Disease Surveillance Center in Japan reported that all
influenza A virus infections during this period were H1N1 infections.
Seven of the 8 employees infected had never taken TJ-41 (group 1 compared
with groups 2-4, P <.05 by Mann-Whitney U test). The 1 infected
employee who had taken TJ-41 was placed in group 3
because the diagnosis was confirmed 4 weeks after treatment was started. The other seven infected employees were given oseltamivir and recovered within 3 days,
Our experience suggests that TJ-41 should be investigated for its
possible ability to prevent H1N1 virus infection. This herbal medicine has
few adverse effects and a cost of approximately 1 British pound per day.
From the beginning of November 2009, seasonal and H1N1 influenza vaccines
were introduced. Therefore, comparison among the four groups is difficult
to determine the preventive effect against influenza A/H1N1 virus by TJ-41
after November. The mechanism of action of TJ-41 remains unknown and
1. Liam J Donaldson, Paul D Rutter, Benjamin M Ellis, Felix E C
Greaves, Oliver T Mytton, Richard G Pebody, Iain E Yardley, Mortality from
pandemic A/H1N1 2009 influenza in England: public health surveillance
study. BMJ 2009;339:b5213, doi:10.1136/bmj.b5213
2. Gerberding JL. Influenza in 2009: new solutions, same old
problems. JAMA. 2009;302(17):1907-1908.
3. Baz M, Abed Y, Papenburg J, Bouhy X, Hamelin ME, Boivin G.
Emergence of oseltamivir-resistant pandemic H1N1 virus during prophylaxis.
N Engl J Med. 2009; 361(23):2296-7
4. Lipman MM. Herbal medicine. N Engl J Med. 2003;348(15):1498-1501.
5. Yamaya M, Sasaki T, Yasuda H, et al. Hochu-ekki-to inhibits
rhinovirus infection in human tracheal epithelial cells. Br J Pharmacol.
6. Mori K, Kido T, Daikuhara H, et al. Effect of Hochu-ekki-to (TJ-
41), a Japanese herbal medicine, on the survival of mice infected with
influenza virus. Antiviral Res. 1999;44(2):103-111.
Competing interests: No competing interests