Japan announces 16 possible cases of avi?ria grippe [H5N2]

[Theresa42]

babelfished from Portugese:

Japan announces 16 possible cases of aviária grippe [H5N2]
Quinta, 11 de maio de 2006

The authorities of health of the Japanese province of Ibaraki had informed today that 16 people of this neighboring area the Tokyo can have been infectadas for the aviária grippe, even so have not developed the symptoms of the illness.

In declarations cited for the Kyodo agency, the government of Ibaraki indicated that danger does not exist to infect other people. According to such information, the 16 people would have been infectadas for cepa H5N2 of the aviária grippe, that is not so virulent as variant H5N1, that more than killed one hundred people in the world all.

With these possible cases of aviária grippe in human beings, she goes up for 93 the number of people who can have been infectadas at some moment for the virus in Japan - 86 in Ibaraki and seven in the neighboring province of Saitama, to the northwest of Tokyo.

The Bank of Desenvolvimento Asiático (BDA) alerted that a pandemic of aviária grippe could cost about USS 283 billion alone in Asia. Moreover, it would provoke a economic contraction in the continent.

The Work, Health department and Well-being of Japan initiated a shock plan to face an eventual epidemic of aviária grippe, that in theory could cause up to 640 a thousand deaths in the country if it was transmitted between human beings.

This plan of shock contemplates the declaration of the state of emergency in Japan in epidemic case, to reduce the contágio and to prevent the panic.

http://noticias.terra.com.br/ciencia...-EI298,00.html

[Theresa42]

Japan Farm Workers May Have Been Exposed To Bird Flu [H5N2]

5/11/2006 6:48:00 AM
Japan Farm Workers May Have Been Exposed To Bird Flu [H5N2]

TOKYO (AP) -- Japan's Health Ministry said Thursday that 93 poultry farm workers may have been exposed to a mild form of the bird flu virus last year. The ministry had said in a preliminary report in January that 77 people were exposed to and possibly infected with the H5N2 strain, which was not previously known to infect humans.

It is milder than the virulent H5N1 strain that has recently spread from Asia to Europe. Most of the 77 were poultry farm workers in Ibaraki and Saitama prefectures (states) near Tokyo.

After conducting tests on more workers, the ministry found that 16 more in Ibaraki may have also caught H5N2, according to ministry official Hiroshi Takimoto. Preliminary tests on the workers were positive for H5N2 antibodies, indicating they were previously exposed, Takimoto said. While exposure carries with it the possibility of infection and illness, he said none had tested positive for the virus itself or had developed flu symptoms.

The ministry had been testing chicken farm workers since a bird flu outbreak in Ibaraki in June last year. The disease hit Japan in 2004 for the first time in decades. There has been one confirmed human case involving the H5N1 virus in December 2004, but no reported human deaths. About 5.7 million birds have been destroyed in Ibaraki following the H5N2 outbreaks.

http://www.cattlenetwork.com/content...ontentid=36033

[Laidback Al]

Japan report on H5N2 exposure (Jan 2006)

From http://www.mhlw.go.jp/english/topics...a/avian02.html

January 10, 2006


<CENTER>Interim report of the results of A/H5N2 avian influenza ( low virulent )
serum antibody tests in Ibaraki and Saitama prefectures</CENTER>

National Institute of Infectious Diseases

Summary

In order to verify if A/H5N2 avian influenza virus was transmitted to humans after a series of epidemics were reported at chicken farms in Ibaraki and a farm in Saitama prefecture since June 2005, serum neutralizing antibody values were measured. All the tests have not been completed, but the current results based on tentative criteria showed positive serological tests among people who had been in contact with infected poultry, suggesting that some people might have been infected with the A/H5N2 virus. Further studies are required for more details.

Study method

Serum neutralizing antibody tests for avian influenza virus A/Ck/Ibaraki/1/2005(H5N2), which had been isolated in Ibaraki prefecture, were conducted on 353 samples among 385 that were first collected and 264 samples that were secondly collected in Ibaraki and Saitama prefectures since the end of June 2005, and submitted to the National Institute of Infectious Diseases for examination until the end of December. The second blood collection was basically conducted one month after the first collection.

The serological evaluation was based on a significant increase of more than four-fold in the antibody values of paired serum samples from the first to the second collection. On the one hand, since the virus of the epidemic has attenuated virulence, it is difficult to specify the time of the epidemic among the poultry at the chicken farms, and it is not possible to specify the time when people were exposed to the virus. Since it could also be considered that antibody had already been produced after earlier exposure to the virus, by the time of the first collection, it is also possible that there is not a significant increase in the antibody values of the paired serum samples. In order to evaluate a single neutralizing antibody measurement to be positive, instead of testing paired serum samples, a new criterion should be established. Since the criteria for a positive neutralizing antibody test for the human A/H5N2 influenza virus have not been established, we established the criteria based on the measured neutralizing serum antibody values in 31 subjects who had not been in contact with infected poultry, as the control group.

Study results

A significant increase of more than four-fold in antibody values of paired serum samples from the first to the second collection, the basis for serological diagnosis, was observed in 15 cases. No increase in antibody values was observed among subjects who were engaged in killing poultry.

In the control group, 97% of the subjects who had not had any contact with poultry showed antibody values of 10 or below, and there were no values of 40 or over. Based on this fact, samples with an antibody value of 40 or over were tentatively defined as positive. According to this criterion, besides the 15 whose paired serum samples showed a significant increase in antibody value, as shown in the table, 49 samples from the first collection and 24 from the second were found positive. Of these, 11 were found to be positive both in the first and the second collections.

As a result, 77 among the 353 were found to have a positive serological test.



<CENTER><TABLE border=1><TBODY><TR align=middle><TD></TD><TD>Employees in chicken
farms etc.
</TD><TD>Health workers</TD><TD>Total</TD></TR><TR><TD>Number of subjects with increased antibody values
(more than four-fold)
</TD><TD noWrap align=middle>15</TD><TD noWrap align=middle>0</TD><TD noWrap align=middle>15</TD></TR><TR><TD>Positive only in the first collection</TD><TD noWrap align=middle>34</TD><TD noWrap align=middle>4</TD><TD noWrap align=middle>38</TD></TR><TR><TD>Positive only in the second collection</TD><TD noWrap align=middle>13</TD><TD noWrap align=middle>0</TD><TD noWrap align=middle>13</TD></TR><TR><TD>Positive both in the first and second collections</TD><TD noWrap align=middle>10</TD><TD noWrap align=middle>1</TD><TD noWrap align=middle>11</TD></TR><TR><TD>Total number of positive cases</TD><TD noWrap align=middle>72</TD><TD noWrap align=middle>5</TD><TD noWrap align=middle>77</TD></TR><TR><TD>Number of subjects in the first collection</TD><TD noWrap align=middle>319</TD><TD noWrap align=middle>34</TD><TD noWrap align=middle>353</TD></TR><TR><TD>Number of subjects in the second collection</TD><TD noWrap align=middle>231</TD><TD noWrap align=middle>33</TD><TD noWrap align=middle>264</TD></TR></TBODY></TABLE></CENTER>

Discussion

A serological test is a method that does not detect pathogens directly, but is based on indirect speculation of infection by measuring the antibody response in a host against the infection. When strict serum sample pairs at the time of and after exposure are not available, the study results are interpreted based on the criteria for a positive result, based on a comparison of the antibody value distribution between an infected and a non-infected group. It is rather difficult to obtain samples from an apparently infected group and a non-infected group in human studies including the present study. Therefore, it should be noted that some of the study results are tentative.

Based on the fact that a significant increase in paired serum samples from the first to the second blood collection was observed in 15 cases, a quarter of the 62 judged positive based on single serum values. If it is assumed that these positive cases had been infected with the virus, it seems that most had already produced antibody due to exposure to the virus by the first collection. This is consistent with the fact that the virus infection was already terminated, since virus was not isolated, only antibody was detected in most poultry at chicken farms when avian influenza was confirmed.

Most subjects who may be infected are the employees at chicken farms. It is considered that infection occurred due to contact with infected poultry or their feces and urine in the absence of appropriate preventive measures because infection had not been confirmed yet at the infected chicken farms.

On the other hand, for health workers, the first blood sample was collected when they started working at the farms, so it is relatively easy to detect infection due to their infection control activities. No significant increases in paired serum samples were observed among health workers, and it is considered that there were no infection control activities, at least. Of the 5 positive cases at the first test, 3 did not have a history of contact with poultry. Two who had a history of contact with poultry might have been infected from poultry, before control activities started. The other 3 with no history of contact were possibly infected by exposure to a similar virus, or by administration of anti-viral agents before control activities started, but it is not clear now.

In the current serological study based on the tentative criteria, there are 77 positive cases suggesting infection, but no influenza-like symptoms were observed. Since avian influenza is not persistent, and the incubation period for H5N1 virus is 2 to 7 days, it is considered that these positive cases have no possibility of contracting the disease in the future.

[Shannon Bennett]

Re: Japan announces 16 possible cases of avi?ria grippe [H5N2]

Now here is a bold statement!

In the current serological study based on the tentative criteria, there are 77 positive cases suggesting infection, but no influenza-like symptoms were observed. Since avian influenza is not persistent, and the incubation period for H5N1 virus is 2 to 7 days, it is considered that these positive cases have no possibility of contracting the disease in the future.

If this is true then we should be incubating H5N2 for protection from pandemic.