Vol. VII, No. 03~ EINet News Briefs ~ January 16, 2004
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In this edition:
1. OVERVIEW OF INFECTIOUS-DISEASE INFORMATION
Below is a semi-monthly summary of Asia-Pacific emerging infectious diseases.
China ( Guangdong )—Third suspected SARS case
Evidence of a possible link between SARS and animals from wildlife markets popular in the region has prompted Guangdong authorities into a mass culling. Thousands of civets—considered a local delicacy—have been slaughtered after researchers named the animal as the possible source of the virus before it jumped to humans. Guangdong is widely accepted as the place SARS first emerged to such devastating effect in November 2002. "Basically, most of the civet cats in Guangdong have been slaughtered," one official at the Guangzhou Anti-SARS Office said on Sunday. Cleaners were also sweeping streets and targeting potential disease spreaders such as rats, cockroaches, flies and mosquitoes. The Guangzhou-based newspaper Yangcheng Evening News said that a three-day campaign on eliminating rats was drawing more than 10,000 people. It said more than 10 tons of grain had been laced with poison and deployed in "millions of places" to kill rats. "Exercise caution in dealing with rat carcasses," it said, quoting authorities.
Public health experts have said they think SARS can be contained as long as a good surveillance and isolation system is in place. "We feel that this is a disease where we may see small numbers of cases," said Julie Hall, a WHO expert in Beijing . "We may even see very small numbers of clusters, but we should not see the large outbreaks that we saw before if the system is strong enough to be able to do that early detection."
China ( Guangdong )—Follow-up on suspected SARS cases
The MOH announced that the male patient is now considered a suspected case of SARS. He is said to be in a stable condition in hospital. He was admitted and isolated on 6 Jan 2004 after developing symptoms on 31 Dec 2003. The Ministry says 12 close contacts and 12 casual contacts of the male patient have been traced, and all are in good condition at this point. The other suspected case—the waitress reported on 8 Jan 2004—is currently stable. The 48 identified close contacts and 52 normal contacts presented no medical abnormalities. Of those contacts, 37 close contacts and 19 normal ones have been discharged from medical observation.
Two laboratories in Hong Kong have been contacted, and both are prepared to conduct further tests on samples from both patients. The MOH requested samples from both cases be referred to the international SARS laboratory reference network for further analysis. The WHO group currently in Guangdong will also discuss some of the details of both these cases. The WHO team is part of a joint mission with the MOH looking at all possible sources of SARS infection—from animals, humans, or the environment.
Viet Nam—Avian influenza A(H5N1) in humans and poultry
At present, there is no evidence that human-to-human transmission has occurred. No reports indicate that health care workers have been infected. The presence of avian influenza A(H5N1) in samples from three of these cases was confirmed by Hong Kong 's National Influenza Center, which is a member of the WHO Global Influenza Surveillance Network. Samples have also been sent for analysis to Japan 's National Institute for Infectious Diseases, another member of the WHO influenza network. Results are awaited shortly. WHO is providing support to Vietnamese health authorities in their investigation and in the prevention of further spread to humans.
To date, the virus, which spreads rapidly and has a mortality in chickens approaching 100 per cent, has resulted in the deaths of 40,000 chickens and the culling of 30,000 more. The relationship between the human and poultry outbreaks of avian influenza A(H5N1) in Viet Nam is not fully understood at present. WHO and Viet Nam 's Ministry of Health are undertaking investigations to determine the source of the human cases and whether human-to-human transmission has occurred. The situation is also being followed closely by the country's Ministry of Agriculture and Rural Development.
An outbreak of avian influenza A(H5N1) occurred in South Korea in December 2003. On Monday, Japanese authorities announced the death of 6,000 chickens at a single farm as due to infection with the same strain of the virus. These outbreaks mark the first cases of avian influenza in South Korea , and the first cases in Japan since 1925. No human cases of infection with the avian influenza virus have been reported in either of these outbreaks.
Avian influenza strains normally infect birds only. The first cases of human infection with avian influenza A(H5N1) were identified in 1997 in Hong Kong. The virus infected 18 people and caused six deaths. Genetic studies subsequently linked the outbreak in humans to an outbreak of highly pathogenic avian influenza in poultry. The immediate culling of around 1.5 million poultry in Hong Kong is thought to have averted a larger outbreak in humans.
WHO regards every case of transmission of an avian influenza virus to humans as a cause for heightened vigilance and surveillance. Influenza viruses are highly unstable, and the co-circulation of highly pathogenic animal viruses with human viruses could create opportunities for different species-specific viruses to exchange genetic material, giving rise to a new influenza virus to which humans would have little, if any, protective immunity.
East Asia—Nations act to stem Asian bird influenza outbreak
WHO said that three people in Vietnam had died from bird flu. It is investigating a further 12 cases. Cambodia imposed a temporary ban on imports of bird meat and eggs from countries struck by bird flu. Hong Kong stopped imports from South Korea and is considering a ban on Japanese poultry. Beginning on 14 Jan 2004 , Hong Kong authorities will begin vaccinating chickens entering the territory and will step up inspections of food markets and farms. Japan 's agriculture ministry on Tuesday set up a task force to find ways to prevent the spread of bird flu after 6000 chickens died in December 2003 at a farm in Yamaguchi prefecture in the country's first bout of bird flu in 79 years. Taiwan on Tuesday banned imports of poultry and related products from Japan , while Thailand said it had killed hundreds of thousands of chickens because of an unrelated bout of poultry cholera.
The outbreak of bird flu comes just weeks ahead of the lunar new year celebrations, traditionally marked by feasting and festivities in China and by Chinese people, pushing poultry sales higher. It also comes at a sensitive time for Japan 's agriculture, food, and restaurant industries, which had barely recovered from the outbreak of mad cow disease in Japan in 2001, when a new beef crisis hit the US in December 2003. The US provides about 30 per cent of Japan 's beef imports.
One fourth of all Dutch poultry were slaughtered in 2003 to eradicate bird flu at a cost of hundreds of millions of Euros, and part of the industry is unlikely ever to recover from the disaster, sector specialists said yesterday. The Netherlands , the European Union's largest poultry exporter, slaughtered 30.7 million birds at 1,300 farms to contain the outbreak, which was first discovered in March 2003 and led to one human death.
Office International des Epizooties (OIE) is monitoring the epidemiological situation very closely with the support of the member countries involved. OIE has been updating the international standards on avian influenza. Issues that have been addressed include the safety of poultry products for human consumption and for international trade, as well as updated control methods of the disease. OIE member countries will examine the developments and discuss them during the forthcoming general session of the OIE in May 2004.
OIE is working in close collaboration with WHO and, in this respect, a joint WHO/OIE/FAO delegation of scientists and risk managers will soon be conducting consultations and investigations in countries in Asia, starting with Vietnam. OIE, through its experts and its world network of reference laboratories and collaborating centers, remains at the disposal of all Member Countries requesting assistance in the definition of policies on diagnosis, control, and eradication of the disease in animals.
East Asia—Avian influenza A(H5N1) in humans in Viet Nam and poultry in Asia , WHO update
The H5N1 strain implicated in the outbreak has now been partially sequenced. All genes are of avian origin, indicating that the virus that caused death in the three confirmed cases had not yet acquired human genes. The acquisition of human genes increases the likelihood that a virus of avian origin can be readily transmitted from one human to another. Investigations are focusing on the source of infection and possibilities of human-to-human transmission. An outbreak of highly pathogenic H5N1 avian influenza was detected in southern Viet Nam in the beginning of January 2004. The outbreak is now known to have spread to other provinces in the country. Reports indicate that pigs and ducks have also been infected. Yesterday, officials in the Republic of Korea announced the spread of H5N1 avian influenza to an additional farm. Japan is also experiencing an outbreak in poultry caused by the H5N1 virus.
In response to these developments, WHO has initiated a series of activities. These include support to national authorities in investigating the outbreaks and enhanced surveillance activities in Asia . WHO has also initiated the development of candidates and reagents for vaccine production, and antigenic and genetic assessments of the H5N1 strain to provide up-to-date diagnostic tests to national influenza centres. The WHO Global Influenza Network will receive virus and clinical specimens shortly. As a precautionary measure, network laboratories will immediately begin work on the development of a strain that can be used to produce a vaccine.
Singapore —Authorities caution against eating raw oysters as diarrhea cases rise
However, AVA warns that frozen oysters can still cause diarrhea even if they pass the test, especially if they are not thawed properly or displayed at room temperature for too long. Undercooked or raw bivalve shellfish such as oysters and clams can transmit a variety of illnesses including viral diarrhea, typhoid fever, and hepatitis A. Toxin diseases such as paralytic shellfish poisoning can also be transmitted, which acquire the toxin from dinoflagellates through the food chain. This toxin is not heat-sensitive; even proper cooking will not lessen its effect.
Philippines ( Luzon )—Japanese encephalitis alert
Japanese encephalitis has no specific treatment. Fantone said Japanese encephalitis virus is normally transmitted by the culicine mosquito Culex tritaeniorhynchus . Fantone stated that: "80 percent of Japanese encephalitis victims get well after showing symptoms. The rest suffer from some form of mental retardation." The mortality in most outbreaks of Japanese encephalitis is below 10 percent, but may be higher in children. Neurological sequelae among patients who recover may be detectable in up to 30 percent of cases. Several vaccines are available: a formalin-inactivated vaccine has been used successfully in Japan and neighboring countries, and both an inactivated cell-culture vaccine and a live attenuated vaccine have been used in China.
Meanwhile, Angeles City Mayor Carmelo Lazatin appealed to residents to rid their surroundings of possible breeding grounds of mosquitoes following a surge in dengue fever cases in the city. Dr. Rolando Esguerra, city health officer, said 174 people have been stricken with dengue since January of 2003; seven of them died.
Indonesia ( East Java )—Chikungunya fever increase in Magetan district
Chikungunya fever, since its appearance in West Java in December 2002, is spreading eastwards throughout the Indonesian archipelago. Chikungunya fever is an arthropod-transmitted viral disease. Arthralgia is the most typical sign, and the acute phase of the disease lasts for two to four days with recovery in five to seven days. The other typical signs/symptoms of the disease include fever, nausea, vomiting, and headache.
Indonesia ( West Jakarta )—Health agency confirms chikungunya cases
Like dengue fever, chikungunya fever is characterized by an extremely high fever. The health agency has made efforts to prevent the disease from spreading further by isolating and fumigating the area, providing information and free medical treatment, and sterilizing breeding grounds for mosquitoes. "We're calling on the people to help eradicate breeding grounds of the mosquitoes, as chikungunya virus infection usually occurs at the beginning of the year," said Evy. Residents suspect that flooding caused by spillage from a nearby construction site and the clearing of shrubs and trees had contributed to a rise in the number of mosquitoes in the area.
India (Bihar)—Leishmaniasis (kala-azar)
Leishmaniasis is transmitted by the bite of an infected female sandfly. The vector can become infected when taking a blood meal from a host. The disease is characterised by irregular bouts of fever, substantial weight loss, swelling of the spleen and liver, and anaemia." We are ensuring that DDT is sprinkled in all the states and extra care is taken in the three districts," said Jharkhand health minister Dinesh Sarangi.
Australia (West)—Ross River virus infection alert for Perth
The state is poised to record a similar number of cases during the peak summer months, as in the last big outbreak three years ago. Doctors have notified authorities of 287 cases since the annual surveillance period began in July 2003–241 of which occurred in the relatively populous southwest regions, stretching from Mandurah to Esperance. In the Northern Territory , northern Western Australia , and Queensland , an infection peak is anticipated in January 2004, as the wet season ends. Ross River virus infection is a notifiable disease, but a significant number of cases are thought to go unreported. Kangaroos, wallabies, and a few smaller mammals are the main hosts for the virus–mosquitoes carry it from the animals to humans.
Health Department acting medical entomologist Sue Harrington said, while Perth had recorded few cases so far, the number of cases will likely increase as infected holiday-makers return home and suburban mosquito populations pick up the virus. More than 100 cases may be recorded in Perth as a result. Only about 1/3 of people bitten by an infected mosquito develop symptoms, which are similar to those of influenza and include swelling and pain in joints, rashes, fever, and headaches. Some patients are debilitated for months or years, or find symptoms can recur.
Ross River virus is endemic in most coastal regions of Australia and since the 1980's appears to have extended its geographical range to include most of the island communities of the South Pacific. The mosquito vectors vary according to the local environment. Fortunately, illness in humans–although occasionally prolonged and painful–is not fatal and recovery is complete.
Chile ( Los Angeles)—Hantavirus pulmonary syndrome cases from rural area
The disease is mainly transmitted in Chile by the long-tailed pygmy rice rat Oligoryzomys longicaudatus , which is found in most of the country. Vacationers—mainly campers in forest areas—and farmers are at greatest risk. Rodents spread the virus via urine, droppings, and saliva.
The virus is mainly transmitted to people when they breathe in air contaminated with the virus. The initial symptoms are similar to those of the flu, but victims later develop kidney and lung complications, which in 50 percent of the cases are fatal. To prevent the infection from spreading, health-care officials have emphasized the importance of enforcing strict hygiene measures, mainly during the Southern Hemisphere's summer months, December through February.
Fortunately, in Chile the mortality rate from hantavirus infection has declined from 60 percent in 1996-1997 to 29 percent in 2002 and 30 percent in 2003. As of 2 Jan 2004, 57 cases of hantavirus cardiopulmonary infection (HCI) have been confirmed, a figure lower than that observed in the same periods of 2002 and 2001 (65 and 81 cases, respectively). Seventeen deaths were reported, which represents a case fatality rate of 30 percent.
Influenza update—Northern Hemisphere
Following last week's update on the A(H5N1) outbreak in the Republic of Korea, the National Influenza Centre in the Republic of Korea has finished sampling sera from people in contact with suspect infected animals and nearby residents, and will start serological studies shortly. Avian influenza virus A(H5N1) has been identified as the cause of an outbreak of avian influenza in two southern provinces of Viet Nam; there is also information on outbreaks of avian influenza in other provinces. The virus, which spreads rapidly and has a mortality approaching 100 per cent in chickens, has resulted in the deaths of 40,000 chickens and the culling of 30,000 more. Pigs and ducks are also reported to have been infected.
Since the end of October 2003, hospitals in Hanoi and surrounding provinces have admitted 14 people with severe respiratory illness—13 children and one adult (the mother of a deceased child). To date, 11 of the children and the adult have died. The National Institute of Hygiene and Epidemiology in Viet Nam and the National Influenza Centre in Hong Kong Special Administrative Region of China confirmed that three of these cases were infected with avian influenza A(H5N1) viruses. At present, there is no evidence that human-to-human transmission is occurring, and no health care workers have been infected.
Republic of Korea
Preliminary Assessment of the Effectiveness of the 2003--04 Inactivated Influenza Vaccine—Colorado , December 2003
In order to see the entire article, please visit the following site: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5301a3.htm
Bovine Spongiform Encephalopathy in a Dairy Cow—Washington State , 2003
In order to see the entire article, please visit the following site: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5253a2.htm
Fatal Respiratory Diphtheria in a U.S. Traveler to Haiti—Pennsylvania, 2003
In order to see the entire article, please visit the following site: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5253a3.htm
Ministers attend emergency meeting to outline final push to stop polio by end 2004
In order to see the entire article, please visit the following site: http://www.who.int/mediacentre/releases/2004/pr4/en/
Mass vaccination aims to limit impact of cholera in Mozambique
In order to see the entire article, please visit the following site: http://www.who.int/mediacentre/releases/2004/pr3/en/
Avian influenza – WHO fact sheet
Neonatal vaccination workshop notice
The workshop is coordinated by the National Vaccine Advisory Committee's Future Vaccines Subcommittee, CDC, the U.S. Food and Drug Administration, the National Institutes of Health, and the Task Force for Child Survival and Development and is supported by a grant from the DHHS National Vaccine Program Office. Additional information about the workshop, including submission of abstracts, registration, and hotel accommodations, is available from the Task Force for Child Survival and Development, telephone 404-592-1425, e-mail email@example.com , and from CDC at http://www.cdc.gov/nip/events/neonatal_wkshop .
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