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Published Date: 2005-07-28 23:50:00
Subject: PRO/AH/EDR> Streptococcus suis, porcine, human - China (Sichuan)(02)
Archive Number: 20050728.2194

STREPTOCOCCUS SUIS, PORCINE, HUMAN - CHINA (SICHUAN) (02)
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[1]
Date: Thu, 28 Jul 2005
From: ProMED-mail <promed@promedmail.org>
Source: The Pig Site [edited]
<http://www.thepigsite.com/LatestNews/Default.asp?AREA=LatestNews&Display=9787>

Pig disease toll now 27
-----------------------
A mysterious pig-borne disease has spread to 6 more towns in southwest
China, with the number of people killed rising to 27, the Government said
today, 28 Jul 2005, as it scrambled to reassure the public. The ministry
of health said the total number of people affected increased to 131 by noon
of 27 Jul 2005 -- 3 more deaths and 14 more cases than the day before.
6 more towns in Sichuan province reported cases on 27 Jul 2005, in addition
to the 2 Sichuan cities Ziyang and Neijiang, where people first fell ill
after killing pigs [that were] foaming at the mouth in Jun 2005, the
ministry said on its website.
The WHO has said it was baffled as the disease, caused by the
_Streptococcus suis_ bacterium, had never before stricken so many people at
one time, raising fears it had become more virulent. The Chinese Government
was working to reassure the public that it has got a grip on the epidemic.
Only 2 of the 14 new cases were people who fell ill this week, while all
the other new cases were of patients who had been sick for some time but
were recently diagnosed, the health ministry said.
All the victims were farmers who slaughtered infected pigs or others who
processed or handled the pork and ate it. There was a long tradition of
farmers in the area eating sick pigs instead of burying them due to
poverty, farmers contacted by telephone in the mountainous region told AFP.
"We've eaten sick pigs for as long as I can remember. It's because farmers
here are poor. It's such a waste to bury them when they get sick," Lei
Changfu, an elderly woman living in a farm in Ziyang city, said. However,
she and other local farmers said they had never seen so many people get
sick from eating infected pork.
Farmers called over their relatives and neighbors to help them slaughter
the sick pigs, even though the animals were foaming at the mouth, according
to newspaper accounts. Entire families and neighbors pitched in to shave
the hair off the killed swine, wash the internal organs and chop up the
meat to distribute. The victims had open wounds, which allowed the bacteria
to get into their body, the health ministry said.
The health ministry issued a national guideline on 27 Jul 2005 ordering
farmers to bury infected pigs deep in the ground or burn them, to prevent
other animals such as dogs from coming into contact with them.
[Byline: Cindy Sui]
--
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[2]
Date: Thu, 28 Jul 2005
From: ProMED-mail <promed@promedmail.org>
Source: Reuters [edited]
<http://today.reuters.com/News/CrisesArticle.aspx?storyId=HKG37051>

Experts puzzled by China's swine bacteria outbreak
----------------------------------------------
Scientists are perplexed by the unusually high, and rising, number of
deaths in southwestern China from a mysterious pig-borne disease, and they
are beginning to question if it is indeed swine flu. 27 people in Sichuan
province have died in recent days from the disease, which has sickened 104
others. Chinese health authorities have identified the culprit as
_Streptococcus suis_, a form of what is commonly known as swine flu [Swine
flu is not a good term for this, since it is not an influenza illness -
Mod.LL]. They say all those taken ill had slaughtered, handled or ate
infected pigs, and there had not been any human-to-human transmission of
the bacteria.
The authorities have dismissed speculation that the deaths were caused by
bird flu, a virus that has killed over 50 people in Asia since late
2003. Nevertheless, medical experts outside mainland China said the
unusually high mortality rate of 20 percent and reports that many of the 27
victims died within a day of showing symptoms were inconsistent with what
is known so far about human _Streptococcus suis_ infection. Though endemic
in swine, human infections are rare. And where they have occurred,
mortality rates have been below 10 percent.
"It could be another disease altogether, it need not be _Streptococcus
suis_, because the presentation is so atypical," Samson Wong, a
microbiology associate professor at the University of Hong Kong, told
Reuters. "In past literature, there have been 1 or 2 cases when people
died within 36 hours, but those were exceptions rather than the rule. The
deaths in China are very unusual," Wong said. Wong also said many patients
in Sichuan were bleeding under the skin, a symptom that has been cited in
only 2 or 3 cases in medical literature on the bacteria.
Although the WHO says that clinical diagnosis of the disease in Sichuan
seems to be consistent with past outbreaks, it too is puzzled by the
unusually high incidence. "It's not clear to us why we're seeing such a
large case number," said WHO spokesman Bob Dietz. The last outbreak of
_Streptococcus suis_ in China was in 1998, and involved 22 people.
Dietz stressed that China's diagnosis of _Streptococcus suis_ was only a
preliminary one, especially since authorities there have confirmed the
presence of the bacteria in only 5 cases through laboratory tests. Over 70
other cases were only clinically diagnosed. "We'd like to see more of that
gold standard proof (laboratory tests). You also have to discount the fact
that there wasn't another co-infection from something else," he added.
_Streptococcus suis_ is also known to cause deafness in humans, but that
has yet to surface in Sichuan, Dietz said. [The deafness is a symptom
associated with meningitis due to _S. suis_, not clearly described here. -
Mod.LL]
Chinese scientists are analysing the bacteria and have so far decoded 7 of
its genes, which they say are no different from _Streptococcus suis_
bacteria isolated in past outbreaks overseas. That suggests that the bug in
Sichuan has not mutated.
"A bacterium has many, many genes, not just 7. So could it be that there
are other genes that are now different? Could this be a more virulent form
of _Streptococcus suis_? It's all too early to say," Wong said.
[Byline: Tan Ee Lyn]
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[3]
Date: Thu, 28 Jul 2005
From: ProMED-mail <promed@promedmail.org>
Source: Sydney Morning Herald (Australia) [edited]
<http://www.smh.com.au/news/world/diseased-pigs-dug-up-and-resold-for-eating/2005/07/28/1122143967005.html?oneclick=true>

Diseased pigs dug up and resold for eating
------------------------------------------
Unscrupulous traders dug up the day-old carcasses of diseased pigs and sold
them for human consumption, a Chinese newspaper has reported. The WHO has
been puzzled by the extent and severity of an outbreak of _Streptococcus
suis_ that has claimed the lives of 27 people among 131 infected in the
cities of Ziyang and Neijiang, in the south-western province of Sichuan.
The bacterium is common in pigs and can cause sickness, but is rare in
humans. Patients develop high fever, bleeding under the skin and toxic
shock. The last big outbreak was in Jiangsu province 7 years ago, when 14
people died.
The provincial capital's Chongqing Evening News has reported that police
stumbled upon a trade in animals condemned as infected, slaughtered and buried.
Last Sun, 24 Jul 2005, they found a pig vendor with 2 dead pigs and a sick
one on his tricycle. He had bought the pigs for a bargain 50 yuan ($8.15)
each. He complied with a police order to bury the pigs, but the next day he
dug them up and sold them in another town for 480 yuan each.
The newspaper said a large group of pig traders in the area were buying
dead pigs and digging up carcasses for resale to butchers. One patient
infected with _Streptococcus suis_ had helped his neighbour butcher a pig
for eating that had died of sickness, a common practice in poverty-stricken
rural areas.
[Byline: Hamish McDonald]
--
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[4]
Date: Thu, 28 Jul 2005
From: ProMED-mail <promed@promedmail.org>
Source: XinHuaNet.com [edited]
<http://news.xinhuanet.com/english/2005-07/28/content_3280685.htm>

China starts producing pig-borne disease vaccine
--------------------------------------------------
People in southwest China that affected by a pig-borne disease are expected
to receive vaccines soon.
According to experts with the team sent by the Ministry of Agriculture to
the area of the outbreak, the vaccines for _Streptococcus suis_ type II, a
bacterium carried by pigs, will soon be batch-produced in south China's
Guangdong Province and are expected to reach Sichuan Province in about 1
week after being inspected by the Ministry of Agriculture.
Yongshun biomedical company in Guangdong will be the first to mass-produce
the vaccines. It has already produced a small number of vaccines after
receiving emergency training from the expert team. Ning Yubao, a member of
the expert team and researcher with the China veterinarian medicine
monitoring institute, said the vaccine should help control the outbreak.
The Ministry of Health announced 152 confirmed or suspected infections by
noon on Thursday, killing 31 people. All those infected are reported to
have handled sick pigs.
--
ProMED-mail
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[The latest numbers as of 28 Jul 2005 are now 31 deaths and 152
cases. There are 7 more deaths and 21 more cases than 2 days before.
It is plausible that the organism (and possibly toxin) load to which the
patients were exposed was higher if the swine had been dug up after being
buried, with the possibility of further _S. suis_ replication and toxin
production while buried. This could explain the different disease
observations, which have caused observers (including ProMED) to be somewhat
unsure if the _S. suis_ is indeed the etiology.
I am not aware of any trials using a _S. suis_ type 2 vaccine in
humans. Several approaches have been used in swine, however, including
sonicated organisms (1), a non-encapsulated mutant (2), and a hemolytin
subunit of the organism (3).
1. Lapointe L, D'Allaire S, Lebrun A, et al: Antibody response to an
autogenous vaccine and serologic profile for _Streptococcus suis_ capsular
type 1/2. Can J Vet Res. 2002; 66:8-14.
2. Wisselink HJ, Stockhofe-Zurwieden N, Hilgers LA, Smith HE: Assessment of
protective efficacy of live and killed vaccines based on a non-encapsulated
mutant of _Streptococcus suis_ serotype 2. Vet Microbiol. 2002; 84:155-68.
3. Jacobs AA, van den Berg AJ, Loeffen PL: Protection of experimentally
infected pigs by suilysin, the thiol-activated haemolysin of _Streptococcus
suis_. Vet Rec. 1996; 139:225-28.
- Mod.LL]
[Today, 28 Jul 2005, the director of MOA, Mr. Jia Youlin, told the press in
Bejing that testing affected swine for influenza and Nipah viruses, as well
as "other pathogens", has ruled out these agents regarding the recent
disease cases in swine. (The meaning of "other pathogens" is not
clear.) According to laboratory investigations, it became apparent that
the 3 tested strains of _Streptococcus suis_ were resistant to
trimethoprim-sulphamethoxazole, streptomycin, and nalidixic acid but still
sensitive to ampicillin, vancomycin, and imipenem.
The current reports of _S. suis_ cases in humans and in pigs reflects a
significant and commendable change in China's attitude towards openness and
transparency; it may also reflect an enhanced diagnostic effort.
Previously, many instances of morbidity and mortality may have remained
undiagnosed (and certainly unpublished) among rural populations, where --
traditionally, and due to poor living conditions and deficient food supply
-- dead animals were not buried but, in many cases, consumed. Animal
diseases have obviously received even less attention.
The _S. suis_ outbreak of 1998, affecting humans and pigs, to which
reference is made now, remained unpublished until 2002, when it was
reported in a local Chinese journal. It has been made public now after
being put on the Chinese CDC's website, to become cited internationally
(see item 2 in 20050726.2169). It remains to hope that the new tendency
endures and will be broadened to include animal-health issues. - Mod.AS]

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