Strict guardians of animal and human health on Home Services

Jan

Strict guardians of animal and human health

posted by admin in Window Cleaning

Stripping down to their birthday suits is part of the job for scientists working at a high-security laboratory in Geelong, Victoria. Australian lives depend on them leaving their clothes behind. To get to work, the 80 staff at the Australian Animal Health Laboratory (Aahl) must enter changing rooms each morning. Undressing, they put clothes and personal effects into a locker and then proceed, naked, into a small chamber. Sealed by airtight doors, this acts as a shower cubicle on exiting and a barrier preventing microbes being carried into the outside world. A black button is pushed to open a heavy metal door and to enter another changing room. Here, the scientist slips into the provided white overalls or skirt, white shoes, Y-front underwear for men, also white, and a coloured shirt. Our small party of invited journalists from New Zealand does not escape this safety net. We must also run the no-clothes gauntlet, but not before watching a 15-minute video to ensure we do not take a wrong step. One mistake can be embarrassingly costly visitors have been known to walk through the wrong door and into a corridor wearing little more than a fading smile. Far from being overkill, there are good reasons for these strict safety protocols. It is vitally important that foreign, new and emerging diseases remain enclosed within the walls of the biosecurity facility run by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Livestock Industries. More than that, it’s a matter of national security when deadly diseases such as Severe Acute Respiratory Syndrome (Sars) are handled. Aahl’s director, Martyn Jeggo, rates the laboratory as the safest and most sophisticated of its kind in the world, and ahead of Pirbright laboratory in the United Kingdom or Plum Island in the United States. “This laboratory is in a good state and we would argue that it is the most advanced contaminant laboratory in the world,” Jeggo says. He says a “cascade” of back-up protection systems are set to guard against a breakdown, so that no object leaves the building unaccounted for. “An animal goes out the chimney. The only thing allowed out is a human being, and it doesn’t have its clothes on.” The laboratory is recognised as a world authority on rabies, newcastle disease, brucella, avian influenza and Sars, as well as two fish diseases. “It was this laboratory that identified Sars was from bats,” says Jeggo. “If we need to work with a nasty bug that affects animals and humans, we work in an enclosed air supply.” About 75 per cent of all new diseases today come from animals. Recognising this threat, the Australian government has just given Aahl management $A8.5m ($NZ9.8m) to upgrade its secure microbiological laboratories. This includes another 350sq m of BSL4 laboratory, which operates at the world’s highest biosecurity level. In the last five years about $A55m ($NZ63.5m) has been spent on upgrading the facility. By 2010 it will become a genuinely national facility, open for use to Australian scientists outside the CSIRO. The five-floor, self-contained centre lies on the coastal flank of Geelong, a city of heritage buildings and quaintly decorated verandas a product of an early wool boom. Surrounded by the sea, salt flats and a golf course, Aahl is effectively an airtight box contained by thick concrete. On the first two floors sewage collection and waste treatment is carried out. The third floor houses the laboratories and animal housing and above this are two floors containing 1000 air filters. Every room is air filtered. The air pressure inside the building is deliberately low so air is sucked inwards and through the filters. About 3500 sensors send signals to a central monitoring system and three back-up generators are ready to go should the mains power ever fail. This high security explains why our small group of journalists cannot bring in our notebooks, pens, cameras or clothes. In theory they can accompany us, but the catch is that they do not come back out. Cameras would have to be decontaminated, which takes months, and anyway, it destroys them. Spectacles are acceptable, provided they are disinfected afterwards, as are plain rings and small earrings. Access to the facility is difficult but our group, invited by New Zealand’s AgResearch to showcase trans-Tasman science, has been given permission to tour its secure floors. Before entry is permitted, each visitor signs a sheet requiring them to avoid any contact with livestock or poultry for seven days afterwards. With some trepidation, each member of the group tiptoes through the airlock chamber. Then, fully clothed again, we are led to a secure canteen. The eating quarters have the only windows in the secured part of the building. All food and drink must be consumed here. Gordon Abraham, head of disease security, is our escort. He provides pen and paper so notes can be facsimiled through to the outside world. Abraham explains that the building can withstand an earthquake of 5.8 on the Richter scale. “Our colleagues (visit and) go, `wow, you are so fortunate in having all the problems sorted out’. I take my hat off to the forefathers that built this place.” He says scientists are motivated to join Aahl by the innovative nature of the research. “A scientist is like an artist. You want to do something that hasn’t been done before. That is what drives scientists to find the unknown.” Outside an isolation room, one of eight, the group stops. Through a glass window we can see an airtight laboratory containing a steam steriliser, an incubator and microscopes. Should there be a big virus outbreak, each sample would go to its own laboratory to prevent confusion, says Abraham. As the group advances from one area to another, we must pass through chambers decontaminated by formaldehyde gas. At the spotlessly-clean top floors, Abraham reveals how potentially infectious aerosols are removed from the air by rows and rows of filters. A 150mm concrete floor acts as another microbiological barrier. The group re-enters the third floor and goes to the south suite. The zoonotic laboratory is reserved for diagnosing emergency diseases, such as avian influenza, that are hazardous to animals and humans. (Zoonotic diseases are infectious diseases able to be transmitted from animals, both wild and domestic, to humans or from humans to animals.) Bird flu, otherwise known as avian influenza or H5N1, has killed half of the 600 people infected from birds so far. If it mutates to be able to pass between people it could trigger a global pandemic, with fatal results, says Abraham. On the door is a formidable list of the agents being researched Sars, nipah and hendra. (Nipah and hendra are closely related, newly recognised zoonotic viruses. The hendra virus was first isolated in 1994 from specimens obtained during an outbreak of respiratory and neurologic disease in horses and humans in Hendra, a suburb of Brisbane.) When handling a deadly virus, researchers, often vaccinated, have to wear a fully enclosed, heavy plastic suit. These full-body suits take half an hour to put on and have their own air supply from a series of yellow hoses attached to the roof. Should these fail, there are back-up hoses. When the scientists’ work is completed, they must remove and leave behind their laboratory clothes. In their own airlock they take an 11-minute shower, on top of the three-minute shower required to leave the premises. Throughout the building we are free to observe scientists at work, except in the animal facilities, which house 28 animal rooms and a menagerie ranging from bats to horses. These require a second shower to enter and for practical reasons we do not visit. The record number of showers taken by a staff member in one day is 15. And this obsession with cleanliness is not restricted to possible contaminants on the human body. All waste material, such as paper and other waste leaving the biocontainment area must be destroyed inside the building. Just as the air is filtered to remove infectious aerosols, sewage is heat treated and solid waste is incinerated. Equipment or spare parts brought into the secure area must be signed off after sterilisation. Australians spent $A150m ($NZ173.4m) to build the laboratory in 1985. To replace it today would cost $637m ($NZ736.7m). The wisdom of that early investment was soon revealed when a few years after the building was opened a suspected case of foot-and-mouth disease was able to be ruled out within hours, instead of days, and quarantine bans were lifted. Australia, a major exporter of sheep and cattle, is free from many of the new and emerging animal diseases that can be found around the world. Aahl’s job is to ensure it stays that way for Australia’s livestock, human population and environment. Exotic diseases are carefully brought into the country so scientists can study them in secure laboratories. If there was a major outbreak, they have the technology to identify if it came from terrorist groups or occurred naturally. The laboratory is a reference centre for new diseases such as avian influenza, newcastle disease (a zoonotic bird disease) and bluetongue (a viral disease of ruminants, mainly sheep), and a World Health Organisation base for Sars. It can help the nation respond quickly to a disease outbreak and contain its spread. To ensure potential threats are detected as quickly as possible, the laboratory helps train veterinarians in early recognition of exotic diseases. Among the latest discoveries at Aahl have been the melaka virus, a bat virus that causes respiratory illness in humans. Findings on another new virus are due to be published soon. The nipah virus, a previously unrecorded viral disease that killed more than 100 people and thousands of pigs in Malaysia, later re-emerging in Bangladesh to kill 75% of people infected, was being studied in a high-security laboratory. Containers holding the virus arrive elaborately packaged. Vials of the virus are in a sealed tin, enclosed in yet more sealed tins and, finally, within a wooden box. Not so long ago, the Aahl team played a leading role in identifying new disease threats such as Australian bat lyssavirus, a relative of rabies, and hendra virus, which can be fatal for infected people and horses. In the last 20 years, outbreaks of newcastle disease and avian influenza in poultry have been diagnosed. Billions of dollars in trade have been protected by providing evidence that Australia is free from animal diseases such as scrapie, foot-and-mouth and classical swine fever. Last year the laboratory ran at a budget of $A37m ($NZ42.7m). This is peanuts compared to the potential $12 billion ($NZ13.8b) cost of a foot-and-mouth outbreak in Australia, says Jeggo. Scientists are investigating ways of creating new vaccines, treatments and diagnostic tests to protect animals not only from new diseases but from animal diseases common to Australia. Johne’s disease (affecting the small intestine of ruminants) is among diseases that account for lost animal production and are costly for farmers. By learning more about these diseases scientists can help reduce some of this cost to livestock farming. New-generation vaccines and treatments will protect the future health of production animals. These studies extend to the major diseases of aquatic animals and wildlife. The only animal disease not handled at Aahl is the foot-and-mouth virus, which Australians are adamant will not be allowed entry because of the risk it poses to livestock. Jeggo says the extent of Aahl’s back-up systems exists in no other institution of its kind in the world. “If the rest of Australia drops off the world we can keep going for a month,” Jeggo says. “(It’s) not that we are so damned important, but (that) it will take about a month to decommission the site because we have some powerful viruses here.” At the end of a two-hour tour our group retires to the changing rooms. Knocking to ensure no-one is in our individual passages, we strip and hang up the provided clothes. In the air-lock chamber we have to shower for three minutes, with a blinking light there to remind us. Nails are scrubbed and hair is shampooed. And the imagined micro-organisms are washed away.