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Experts probe discovery of more dead birds in HK

Re: Experts probe discovery of more dead birds in HK

Commentary

H5N1 Clade 7 Cases in China Raise Concerns
Recombinomics Commentary 19:20
February 5, 2009



it is related to a similar type of virus that happened in the southern part of China in the last two years, which is clade 2.3.2.

But it is slightly different from what we have discovered last year in our market and the outbreak in our local farm in December, which is clade 2.3.4.

On the eight human infections of avian flu in the Mainland, we do not have the full report yet. But according to the preliminary information that is given to us, it is similar to the various virus that was isolated in northern China in the last one or two years.

The above comments from today?s press conference on the H5N1 confirmed birds in Hong Kong strongly suggest that the human cases in China (see updated map) are due to clade 7.

Hong Kong regularly has wild bird outbreaks at this time of the year, and this year, like last year is clade 2.3.2. This sub-clade was also in long range migratory birds in Japan and related sequences were also reported in Korea and southeastern Russia last spring.

Human cases in China have been almost exclusively linked to clade 2.3.4, which is closely related to clade 2.3.2 and both are derivatives of the Fujian strain, which is widespread in southern China.

The only other reported human case in China was clade 7, which was the first confirmed case in the mainland from a fatal infection in Beijing in 2003. Clade 7 was also involved in a series of poultry outbreaks in northern China in the 2005/2006. These outbreaks were difficult to control and required use of multiple vaccines.

More recently, the outbreak in Jiangsu in December was also hard to control and was also clade 7. New vaccinations followed that outbreak, which China reported as asymptomatic.

However, some media reports indicated poultry had died, but was still shipped to market. Shortly after these reports the fatal infection in Beijing developed symptoms, as did the mother of the child (3F) who recovered from an H5N1 confirmed infection.

Clade 7 has been reported in areas adjacent to Beijing, although last year it was also found in Vietnam, and the WHO clade 7 vaccine target is a 2008 isolate from Vietnam.

Published sequences from clade 7 from Shanxi or Hunan has a number of receptor binding domain changes flanking position 190, which is also true of the Tamiflu resistant H1N1 spreading through Asia and the northern hemisphere. These changes allow for escape of the virus from host immune responses as well as vaccines. Thus, both H1N1 and clade 7 H5N1 have created vaccine resistance issues.

Confirmation of clade 7 in the human cases would be useful. This clade will have limited cross reactivity with current pandemic vaccines directed against clade 1 or clade 2.

Release of sequences from the outbreaks in Jiangsu, as well as the recent human cases in China and Vietnam would be useful.

.
 
Re: Experts probe discovery of more dead birds in HK

AVIAN INFLUENZA (10): CHINA (HONG KONG)
*****************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>

[1]
Date: Thu, 5 Feb 2009
Source: Xinhua [edited]
<http://news.xinhuanet.com/english/2009-02/05/content_10766219.htm>


A spokesman for Hong Kong's Agriculture, Fisheries and Conservation
Department (AFCD) said Wednesday [4 Feb 2009] that the dead goose and
2 dead ducks found in Sha Lo Wan, Lantau Island in Hong Kong last
week were confirmed to be H5N1 positive after a series of laboratory tests.

AFCD staff collected the carcasses of a goose and a duck on 29 Jan
2009 at a beach near Sha Lo Wan football pitch. Another dead duck was
found on 31 Jan 2009 at the same location.

The spokesman said that 2 more dead chickens were collected on the
coast opposite Yeung Hau Temple in Tai O, Lantau on Wednesday [4 Feb
2009], adding that preliminary tests for the H5 virus are being arranged.

AFCD will continue to closely monitor the situation and investigate
into the possible causes of the recent discovery of bird carcasses,
said the spokesman.

The spokesman said a ban on backyard poultry has been in force since
2006. Unauthorized keeping of 5 kinds of poultry -- chickens, ducks,
geese, pigeons or quails -- is an offense with a maximum fine of 50
000 HK dollars [USD 6450]. Repeat offenders are subject to a maximum
fine of 100 000 HK dollars [USD 12 900].

--
Communicated by:
ProMED-mail Rapporteur Mary Marshall

******
[2]
Date: Wed 4 Feb 2009
Source: The Nation, Thailand [edited]
<http://www.nationmultimedia.com/worldhotnews/30094866/-Hong-Kong-expert-warns-of-%22terrible%22-China-bird-flu-outbreak>


Experts in Hong Kong were carrying out tests Tuesday [3 Feb 2009] on
dead birds washed up on beaches amid fears of a large unreported
avian-flu outbreak in neighbouring mainland China.

Three of 12 birds found on the Hong Kong island of Lantau in the past
5 days have so far tested positive for H5N1, the bird-flu strain that
can be deadly in humans.

Islanders said dead birds have been washing ashore in recent days and
they believe they come from China's Pearl River Delta, which flows
out into the South China Sea surrounding Hong Kong [map at
<http://www.photography.spentbrothers.com/China84/map.jpg>. - Mod.AS].

On Monday [2 Feb 2009] alone, the carcasses of one goose, 5 chickens,
a duck and 2 other birds were found, bringing to 12 the number of
dead birds found on Lantau since Thursday [29 Jan 2009].

Five people in China died of bird flu in January 2009 alone, 2 more
than in the whole of 2008. Three other people were infected.

However, speaking on Hong Kong's government-run radio station RTHK
Tuesday [3 Feb 2009], infectious diseases expert Lo Wing-Lok warned
that the outbreak in China could be far bigger than officials have admitted.

"This is suddenly something very serious," said Lo, a legislator and
chairman of the Hong Kong Medical Association. "We have to confirm
the source of these dead birds, whether it is local or from the mainland."

Lo said there were already indications that "something extraordinary"
was happening in China because of the large number of [human]
bird-flu cases reported in a short period of time.

"In January [2009], there were 8 human cases reported to have come
down with H5N1 infection," Lo said. "The source of the infection, of
course, is poultry. Poultry infection may be widespread in the
mainland, and, because of that, (infected) birds may find their way
across the border through the water currents, through fishing boats,
from visitors bringing a few birds at a time. These are all
possibilities we need to consider."

A Hong Kong government spokesman said officials were working with
mainland authorities to try to work out the source of the dead birds
on the island, which has no poultry farms.

He said the Hong Kong government would "conduct a study on water
currents and weather" to see whether the carcasses were being washed
ashore from China.

The World Health Organization said China has recorded 38 bird-flu
cases since the disease resurfaced in 2003, including 25 deaths.

Hong Kong saw the 1st outbreak in modern times of bird flu to infect
humans in 1997, when 6 people died and 12 others were infected but survived.

Since then, it has carried out 2 mass culls and introduced strict
market controls and border controls with China, avoiding human deaths
in any of the recent bird-flu outbreaks to sweep the region.

--
Communicated by:
David Cameron Duffy, PhD
Professor/PCSU Unit Leader/CESU Director
Department of Botany
University of Hawaii Manoa
Honolulu, HI, USA
<dduffy@hawaii.edu>

[The improved human surveillance in China has most likely been
reflected in the increased numbers of confirmed cases this year
(2009), which is definitely a sign of hard work and training of
health care professionals countrywide. One can only wonder that there
has been a similar lag in surveillance in the Agricultural section,
involving a lot of small farms with the population not reporting
poultry die offs. One suspects that the surveillance among the major
poultry breeders has improved significantly, but that the smaller
producers are still very much below the radarscope and are hiding
their flocks from the official sector when there are die offs. - Mod.MPP]

******
[3]
Date: Wed 4 Feb 2009
Source: AFP [edited]
<http://www.google.com/hostednews/afp/article/ALeqM5iq8X_3NtMiA79Y46b2fmMxRsBjNA>


China may have experienced outbreaks of bird flu among poultry
recently, the UN's Food and Agriculture Organisation said Wednesday
[4 Feb 2009], even though the government had yet to report any cases
this year [2009].

The FAO's comments come after 8 people contracted the H5N1 bird flu
virus in China this year [2009] -- 5 of whom died -- compared with
just 3 cases in all of 2008.

"There must have been some virus circulation or possibly some
outbreaks lately," Vincent Martin, senior technical adviser on bird
flu for the FAO in China, told AFP.

But he said the FAO had received no reports of bird flu cases in
poultry from the agriculture ministry since December 2008, when an
outbreak occurred in the eastern province of Jiangsu.

"There must be some suspicions of the disease reported to the
Ministry of Agriculture, and some of those suspicions might have come
up positive," he said.

"We are waiting to receive some reports describing the overall
epidemiological situation and the results of investigations."

The number of cases in China this year [2009] has aroused some public
concern, although the World Health Organization has said the overall
situation is "within expectations at this time of the year."

Cold weather encourages the spread of the virus, and the Lunar New
Year holiday -- a risky period when hundreds of millions of people
move across the nation to see relatives and eat meals that include
poultry -- has just ended.

But Martin said the pattern this year [2009] was unusual. "There are
more cases than last year [2008], including in places where the
disease was not reported before, like in Jiangsu province (poultry
outbreak) or Shandong province (human case)," he said.

Lo Wing-lok, an infectious disease expert in Hong Kong, said that if
no poultry outbreak in China was accompanying the current human
cases, the latter could have been triggered by a mutation in the H5N1 virus.

"Maybe the virus has been changing so that it becomes a more easily
transmittable virus between bird and man," he said.

So far, 25 people have died from avian influenza in China since the
disease reemerged in 2003, according to World Health Organization figures.

--
Communicated by:
ProMED-mail Rapporteur Mary Marshall

[Hong Kong's HPAI surveillance and reporting records are rather
exemplary; the observations regarding possible unidentified or
unreported outbreaks in mainland China deserve serious attention.
Since, fortunately, no human to human infections are (yet?!) known to
occur, the source of the recent human infections must be sought in
the animal kingdom. The Chinese authorities may consider publishing
details of their recent active surveillance activities undertaken to
investigate the source of said human infections.

China's last (2) reports to the OIE on H5N1 date back to 19 Dec 2008
(Immediate Notification) and 26 Dec 2008 (Follow-up Report 1). They
addressed 2 outbreaks in Jiangsu; see, including map, at
<http://www.oie.int/wahis/public.php?page=event_summary&reportid=7623>.
- Mod.AS]

[see also:
Avian influenza, human (28): China (HN), WHO 20090203.0471
Avian influenza (09): China (Hong Kong), H5 susp. 20090201.0453
Avian influenza, human (27): China (HN) 20090131.0436
Avian influenza, human (24): China (GZ, SD, XJ) WHO 20090127.0367
Avian influenza, human (22): China (GX) 20090126.0347
Avian influenza, human (19): China (GZ) 20090125.0328
Avian influenza, human (18): China, WHO 20090125.0324
Avian influenza, human (17): China (XJ, SD) 20090124.0321
Avian influenza, human - China (05): Xinjiang, fatal 20090124.0305
Avian influenza, human (15): China, transmission questions 20090122.0281
Avian influenza, human (12): China (GZ) 20090121.0263
Avian influenza, human (11): China, WHO Update 20090119.0240
Avian influenza, human (10): China (GZ, SD) 20090119.0230
Avian influenza, human (08): China (HN) 20090118.0217
Avian influenza, human (03): China (Beijing), WHO 20090107.0064
Avian influenza (03): China (HK) 20090106.0048
2008
----
Avian influenza (129): China 20081225.4067
Avian influenza (116): China (Hong Kong), H5 20081210.3879
Avian influenza (106): Bangladesh, China (Hong Kong) 20081019.3312
Avian influenza (87): China (Hong Kong), vaccine efficacy 20080711.2121
Avian influenza (80): China (Hong Kong, Guandong), UK 20080617.1900
Avian influenza (75): China (Hong Kong) 20080607.1814
Avian influenza (41): Viet Nam, China (Hong Kong) 20080308.0951
Avian influenza (34): China (Hong Kong), Laos 20080213.0574
2007
----
Avian influenza (94): Viet Nam, China (Hong Kong) 20070602.1786
Avian influenza, human (58): Egypt, China (Hong Kong) 20070326.1046
Avian influenza, human (55): H9N2, China (Hong Kong SAR) 20070320.0975
Avian influenza (40): Pakistan, China (Hong Kong), Russia 20070222.0658
Avian influenza (32): UK (England), China (Hong Kong), Turkey 20070212.0534
Avian influenza (30): China (Hong Kong), UK 20070209.0512]
...............................................arn/mpp/msp/mpp
 
Re: Experts probe discovery of more dead birds in HK

<TABLE cellSpacing=0 cellPadding=0 width=430 align=left border=0><TBODY><TR><TD class=theme_news_header>Dead crow confirmed H5N1-positive </TD></TR><TR><TD>
spacer.gif

</TD></TR><TR><TD class=theme_text vAlign=top align=left><TABLE borderColor=red cellSpacing=0 cellPadding=3 width=95 background=/NR/ebulletin/Images/en/themes/HealthAndCommunity/poll_background.gif border=0><TBODY><TR><TD width=95>
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A dead large-billed crow found in Ancient Kiln Park at Chek Lap Kok has been confirmed H5N1-positive, the Agriculture, Fisheries & Conservation Department said today.

The carcass was highly decomposed when found on February 5 and required a series of confirmatory testing for avian influenza. There are no poultry farms within 3km of the location.

The species is a common resident bird in Hong Kong.

Meanwhile, department staff inspected 84 villages today. Seven stray chickens were found in Ngau Tam Mei and were destroyed after blood samples were taken.

http://www.news.gov.hk/en/category/healthandcommunity/090210/html/090210en05002.htm
</TD></TR></TBODY></TABLE>
 
Re: Experts probe discovery of more dead birds in HK

Hong Kong: Large-billed Crow tests positive for H5N1 virus (2/9/2009) [AFCD]

Under the present avian influenza surveillance programme on dead wild birds, test result available today(February 10) showed that a dead Large-billed Crow found at Ancient Kiln Park on Lantau was confirmed to be H5N1 positive after testing for avian influenza, a spokesman for the Agriculture, Fisheries and Conservation Department said. The dead bird was collected at Ancient Kiln Park, Chun Kwan Road, Lantau, on February 5.

The carcass was highly decomposed when found and required a series of confirmatory testing for avian influenza.

Test result available today indicated that the dead bird was confirmed to be H5N1 positive.

The spokesman said there were no poultry farms within three kilometres of where the dead bird was found.

Large-billed Crow is a common resident bird in Hong Kong.

Separately, AFCD staff inspected 84 villages in Hong Kong today. Seven live chickens were found unattended in Ngau Tam Mei area during inspections. After taking samples for testing, AFCD has disposed of all the poultry. All relevant government departments will continue to remain highly vigilant and strictly enforce preventive measures against avian influenza.

"In view of the recent cases of H5N1 found in poultry and wild bird carcasses, the AFCD has phoned poultry farmers reminding them to strengthen precautionary and biosecurity measures against avian influenza. Pet bird shop owners, licence holders of pet poultry and racing pigeons have also been reminded to take proper precautions," the spokesman said.

The spokesman said the department would conduct frequent inspections of poultry farms, the wholesale market and the Yuen Po Street Bird Garden to ensure that proper precautions against avian influenza had been implemented.

The department would continue its wild bird monitoring and surveillance.

The Food and Environmental Hygiene Department (FEHD) will continue to be vigilant over imported live poultry as well as live poultry stalls. It will also remind stall operators to maintain good hygiene. The Department of Health will enhance health education and distribute health advice leaflets.

AFCD, FEHD, the Customs and Excise Department and the Police will strive to deter the illegal import of poultry and birds into Hong Kong to minimise the risk of avian influenza outbreaks brought by imported poultry and birds that had not gone through inspection and quarantine.

The latest information on the H5N1 infected birds found in Hong Kong this year is available at the "H5N1 Health Advice" of AFCD website at www.afcd.gov.hk.

"The public can call 1823 Call Centre for follow up if they come across suspicious sick or dead birds, including carcasses of wild birds and poultry," the spokesman said.

Members of the public are reminded to observe good personal hygiene. They should avoid personal contact with wild birds and live poultry and their droppings. They should clean their hands thoroughly after coming into contact with them. Poultry and eggs should be thoroughly cooked before consumption.
-

View Original Article
 
Re: Experts probe discovery of more dead birds in HK

Hong Kong Agriculture, Fisheries and Conservation Department has seized at Shiwan corpse eight birds. According to the Internet

Yesterday, the Hong Kong Agriculture, Fisheries and Conservation Department has released to the public once again to prevent bird flu, the guidelines, saying that the spring outbreak of avian flu are high-risk period. Recently, wild birds and poultry in the corpse found in H5N1 avian influenza virus, a cause for concern. Appealed to the public should be redoubled to prevent bird flu, avoid contact with live poultry, especially poultry died of the disease.

Since January this year, the Hong Kong coastline of East and West wings of the birds found on the body often has many bird carcasses were only confirmed with H5N1 avian influenza virus. Like the shadow of bird flu are diffuse haze of smoke, hung over the city. Bird carcasses in the end they come from? Is a mystery so far.

From the threat of bird flu at sea?

In mid-March, the Hong Kong Agriculture, Fisheries and Conservation Department seized to announce the latest test results of dead chickens, H5N1 positive. Agriculture, Fisheries and Conservation Department statistics show that on January 29 this year, the AFCD Lantau Island, the first time at the beach near Sandy Bay seized the corpse of a ducks and geese. Since then, the western coast at a number of places, including Sandy Bay on Lantau Island, Sham Wat Wan and Shek Wan and Tuen Mun Butterfly Beach and Black Point, were gradually added 38 carcasses of wild birds and poultry. Corpse carried out in the subsequent tests, a total of nine samples of the H5N1 poultry corpse positive for influenza virus.

"In the past the Government to combat avian flu, are focused on chicken farms, bird markets, and imports of wild birds Nature Reserve, the birds, but this time there are bird carcasses to drift from the sea, never thought." Concept in Hong Kong Birds are not without张浩辉President to express concern.

The people of Hong Kong households in free-range chicken carcasses cast into the sea?

West coast, close to Hong Kong Deep Bay in Shenzhen, Shekou, in the face of the east coast of the Pearl River estuary, Zhuhai, Zhongshan, at which the Lingdingyang. Whether or not the dead chickens from the coast of the Pearl River estuary and at little cost to the city? Department of Biology, Hong Kong Science and Technology Institute of China Research Assistant Professor, LIU Hong-bin of the marine environment for many years. "According to the characteristics of monsoon, the east coast of the Pearl River estuary in winter essential Hong Kong into the north-easterly winds are blowing, if the dead chickens from the vicinity of Deep Bay in Shenzhen, while floating down the current, most likely washed up on the West Bank in Hong Kong."

LIU Hong-bin, according to the calculations, from Shenzhen to Hong Kong Deep Bay on Lantau Island, around 48 kilometers away from a straight line, if the downstream, as long as the chicken carcasses will drift to Hong Kong. "In particular, after the rain, from the Deep Bay and Shenzhen River by the salt water to Tuen Mun and Sha Lo Wan."

Eight times successively seized the body of sick chickens and ducks at Sha Lo Wan, head of the Islands District Council, Mr LI Zhi-Feng told reporters, stressed that every winter, Sha Lo Wan and Lantau Island, like other beaches are blowing north wind "blowing from the sea not only to have dead chickens, but also there were dead once, such as water. "

However, the February 9, the Agriculture Department of Guangdong Province, said publicly that die of bird flu discovered in Hong Kong where poultry at the southwest coast of Hong Kong from Shenzhen in recent 17 km, but the sea area in Shenzhen after the cut for the livestock and poultry raising areas, as many investigation and clean-up, no livestock and poultry rearing. Guangdong has been concluded that the province did not bird flu, the Hong Kong chicken carcasses found in the coast does not come from Guangdong.

The Assistant Director of Agriculture, Fisheries and Conservation Dr Liu Kwei-kin was interviewed by reporters said that the corpse is not a clear source of birds, and birds found in the corpse of Sha Lo Wan, the more calm water, the water near the barrier there, so the body of what birds are dropped or go washed up on the past and require further study. As for whether the corpse drift from the mainland to Hong Kong, Dr Liu Kwei-kin is difficult to consider a conclusion.

"If it was free-range poultry in Hong Kong has put the existence of dead chickens into the sea probably sick." Bird-watching will think张浩辉PRESIDENT.

The smuggling of birds hidden

New Territories Chicken Breeders Association chairman Dr whole interview with this reporter's chicken problems are suspected of smuggling, "Hong Kong's poultry smuggling, especially when chilled has happened smuggling, the Government has obviously not enough to combat."

Dr said the whole of Hong Kong within the scope of the smuggling of poultry on the Sha Tau Kok and Islands region, "the mainland near Sha Tau Kok, it more convenient for smuggling by land, while many on the island of Hong Kong, many villagers are fishing boats, sailing to the coast of the Pearl River estuary buy daily necessities city very frequently, and the price of chickens is also very natural. "

Customs and Excise Department an interview with reporters, pointed out that the current supplied to Hong Kong from the Mainland poultry or poultry mainly by imports of Border Crossing Point, in addition to strengthening the inspection of goods for export to Hong Kong and to strengthen maritime patrol intercepted a suspicious vessel, the Customs and Excise Department stopped cross-border passengers, against a small number of individual passengers to carry poultry or birds into Hong Kong activity. However, even if closely monitored, Hong Kong Customs also seized last year, the smuggling of poultry 1630, and Philip think the whole, have not been seized more smuggled chickens are brought into Hong Kong.

The smuggling of chickens,张浩辉give a more credible argument. Last year, 12 months, 1 chicken farms in Hong Kong New Territories after the outbreak of avian flu in Hong Kong immediately suspended imports of live chickens as long as three weeks. And the ensuing winter, are the people of Hong Kong Chinese New Year peak season chicken, chicken from the usual price of 16 yuan / kg, rising to more than 80 yuan / kg. "Chicken prices so expensive, the Hong Kong people love to eat fresh chicken, it will certainly be someone to take the risk, smuggling of chickens."

January 29 from the first time at the coast led to the seizure of the chicken carcasses to 2 month, 3 month intensive appeared dead chickens floating in that area, in the time period on the consumption of chickens and the New Year coincides with the peak period.

http://news.ifeng.com/hongkong/200903/0326_19_1077326.shtml
 
Re: Experts probe discovery of more dead birds in HK

Title: Influence of monsoons and oceanographic processes on red tides in Hong Kong waters.

Personal Authors: Yin KeDong
Author Affiliation: Key Laboratory of Tropical Marine Environmental Dynamics, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.
Editors: No editors
Document Title: Marine Ecology, Progress Series

Abstract: Hong Kong waters in the northern part of the South China Sea are subjected to seasonal oceanographic processes due to monsoonal winds and Pearl River outflow. Several 100 red tides have occurred in Hong Kong waters during 1983 to 1998, and show a clear spatial and temporal distribution. Most (74%) occurred in semi-enclosed NE bays away from the Pearl River estuary, and fewer occurred in western estuarine waters. Most red tides (70%) occurred between December and May, and fewer in summer. However, nutrients are high in the Pearl River estuary, whereas nutrients are generally low in the NE bays (Mirs Bay and Port Shelter) and cannot support the high biomass of red tides. This suggests that there are concentrating mechanisms promoting the formation of red tides in NE waters, either by vertical migration or horizontal aggregation under suitable wind conditions (NE winds and moderate speeds around 6 m s<sup>-1</sup>). The prevailing NE monsoon winds in winter and spring result in downwelling and a longer residence time of waters in the NE bays, creating conditions similar to those of a batch culture, and allowing local inputs of nutrients and vertical migration of phytoplankton in shallow waters to play a dominant role in favour of local red tides. This may be one of the reasons why more red tides occur in winter and spring in semi-enclosed waters. In summer, the SW monsoon winds result in upwelling along the coast, and high river discharge and rainfall cause an increased estuarine circulation in the Pearl River estuary and rapid outflow of the surface water from these semi-enclosed waters. As a result, residence time of these waters decreases, and they may be analogous to semi-continuous or continuous cultures. This may explain why there are fewer red tides in summer. The species occurring most frequently are (in descending order) Noctiluca scintillans, Gonyaulax polygramma, Skeletonema costatum, Mesodinium rubrum, Prorocentrum minimum and Ceratium furca. In general, dinoflagellate red tides occur mostly in April when Si is low, whereas diatom red tides occur in June when Si increases due to the freshwater discharge. Deep oceanic water on the continental shelf is drawn into the NE bays during the upwelling; it is poor in nutrients, and does not favour nutrient acquisition in deep water by vertical migrating dinoflagellates.

Publisher: Inter-Research
http://cat.inist.fr/?aModele=afficheN&cpsidt=16590029





---------------------------------------------------------------------------------------------------

Pearl River Estuary Pollution Project (PREPP) –

http://envf.ust.hk/cis/doc/3.pdf
 
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