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Operator: Good afternoon ladies and gentlemen. Welcome to Health Care, Health and Safety Association Tuberculosis conference call. I would now like to turn the meeting over to Ms. Peggy Swerhun. Please go ahead Ms. Swerhun.

Peggy Swerhun: Thanks Julie. Good afternoon. My name is Peggy Swerhun. I'm a consultant with the Ontario Safety Association for Community and Healthcare and represent the central north east region. On behalf of the Ontario Safety Association for Community and Healthcare, I would like to welcome all participants joining us. Today we are going to present Tuberculosis and following the presentation, we invite you to stay on the line for a question and answer period. Before introducing our speaker, I have a few reminders for the audience. Please make sure that there is no background noise or discussion during your call as this will affect the audio quality. Make sure you come to the microphone if you are conferencing in a large room. Make sure all papers and cell phones have been turned off and finally, if your building has a PA system, you may want to ask them to turn it down or off if possible. It's time to get started so let's proceed.

Our speaker today is Jean Wilson. Jean is the TB Case Manager for St. Michael's Hospital in Toronto. Jean is a Registered Nurse and graduated from Lakehead University in 1991. In 1992 she continued her education at Dalhousie University as an advanced primary care practitioner. Jean came to Toronto in 1995 to complete a master of health science and community health and epidemiology. Prior to coming to Toronto, Jean practiced for four years in the remote fly in First Nations community north of Sioux Lookout and on Baffin Island. Jean is cross-pointed to the Faculty of Nursing at the University of Toronto and is a lecturer for Lakehead University in the Faculty of Nursing Distance Education Program. Her main areas of research are communicable diseases, practice guideline outcome evaluation and disease management. Jean is an excellent speaker on this topic and brings her impressive academic background as well as her practical experience in the field. I'd like to now proceed with Jean's presentation.

Jean Wilson: Thanks Peggy. I would like to thank you for asking me to come and do the presentation today. It's always an honour to be able to do a presentation to the people who are working on the front lines and see tuberculosis on a day to day basis. And so it really is a pleasure for me to be able to talk to you a little bit today. I'm going to start, I understand from Peggy that most of you have my presentation on slides in front of you and that's probably going to guide me as I talk to you today. So hopefully you'll be able to take some notes and so on and feel free to ask me whatever questions and I'll hopefully be able to answer them for you.

This is the outline that I'm planning to follow today for the presentation: I'm going to look at some of the epidemiology of tuberculosis, primarily we're going to look at some global epidemiology but I'm really only going to briefly touch on that to give you a bit of a picture. I think without understanding the global epidemiology, we really miss the essence of what we're going to see in the future in tuberculosis here in Canada. I'm also going to touch a little bit on the national scene of tuberculosis and then I'll focus on the province. I've tried to provide you with some specifics for Ontario specifically. I will talk about mechanisms of transmission of tuberculosis but for the most part I will go into a little more depth on the paths of physiology of tuberculosis because I know most of you work in infection control and are quite interested in more of the modes of transmission and breaking the mode of transmission.

I'm going to talk about early detection, triage of tuberculosis and the diagnostic testing that is out there now that can actually allow us to have early detection of TB. I will then discuss the different isolations, types of isolation that can be utilized in the different health care settings as well as some of the issues associated with isolation. I will also talk a bit about initiating isolation on a patient and discontinuing isolation as well as some of the challenges that we face in hospital settings. I know some of you aren't necessarily in acute care centres but this may also affect you as well. And finally I'm going to talk about some sentinel surveillance when it comes to employees and screening as well.

So I'll start with the global burden of tuberculosis. In 1994 the World Health Organization considered tuberculosis an emergency and tuberculosis is one of the largest emerging diseases as a problem and for those of you who follow things like the G7, there's been quite a bit of money put towards tuberculosis and HIV in order to control it and get some drugs out and that's called the Green Fund. A third of the world's population is infected with tuberculosis in a latent form and there's approximately eight million active cases each year and there are about one point eight million deaths by tuberculosis and half of the active cases are in a pulmonary state meaning that they're infectious. These are global statistics that are probably underestimated due to the fact that most of the burden of tuberculosis is found in endemic countries that are developing. So, accessing accurate statistics by the World Health Organization tends to be an issue for them. But these statistics do come from the World Health Organization

The main areas that are endemic right now are the developing countries, Southeast Asia, sub-Saharan Africa, Eastern Europe and if you also follow HIV you'll find that tuberculosis and HIV go hand in hand and that's certainly the issue in sub-Saharan Africa right now. In places like the former Soviet Union, tuberculosis has become a huge issue since the fall of the iron curtain and literally the dismantling of their public health care system. Not only are they seeing a resurgence of tuberculosis but they're also seeing huge rates of drug resistance and multi drug resistant TB and I am going to talk a little bit about that throughout my presentation. I think that this needs to be sort of the background for where we go forward. Canada sees a large number of immigrants into the country every year and tuberculosis is certainly showing the face of the global TB that we see.

In Canada we see about two thousand new active cases each year and about forty percent of those are in Ontario and that's primarily because Toronto is the main place for new immigrants to land and settle. As you see from the slides that I've provided you, Toronto is the hot spot in Canada for tuberculosis. We see anywhere from four hundred and fifty to five hundred active cases a year. So we see a quarter of all the active cases in the Toronto area and certainly in other areas. Ottawa and Hamilton certainly, they're also seeing a large majority of the cases. So is the GTA as well. I did put in Northwestern Ontario where the picture of tuberculosis is slightly different. About eighteen percent of the active cases in Canada are within the Aboriginal population That's certainly a huge issue but it's definitely different from the picture that we're seeing in the urban areas which is primarily new immigrants.

In Toronto, ninety percent of the active cases are foreign born and most of them are within the first five years of landing in Canada and they're not sure exactly why that is. There's a lot of research being done on why it is that people go from latent tuberculosis into active disease These statistics mirror the ones that they're seeing in the United States and in some other developed countries that have large immigrant populations . They are seeing that in the first five years of immigration, people are moving from a latent state into an active state.

I've given you some more statistics just sort of to give you a picture. Tuberculosis in Canada used to be a disease of old people. That's not the case any more. The mean age of tuberculosis is decreasing and is certainly amongst the foreign born anywhere from twenty to twenty-nine. It's in the working, young, vibrant age group and certainly there's all kinds of challenges with young families and primary bread winners, etc. Across Canada our drug resistance rate is certainly increasing and in Toronto we're seeing it increase at an alarming rate. Across Canada, of the isolates that Health Canada has, ten percent of those are resistant to one or more drugs When we talk about multi drug resistant tuberculosis which by definition is resistance to isoniazid and Rifampin the two main drugs of the four drugs that we use; across Canada one percent of the isolates are multi drug resistant TB. Unfortunately in Toronto we see three times that rate of multi drug resistance and that rate is actually increasing. I know Toronto Public Health has seen even a larger amount of MDR particularly even this year.

So I'm just going to go on to the principles of transmission. As most of you know, this is an air borne disease primarily transmitted through speaking, coughing and I always put in breathing primarily because tuberculosis doesn't necessarily need to be coughed into the air in order for it to be infectious. It is breathed into the bases or the lower alveoli of the lung and that's where the immune mediated response begins . The primary location for infection is in the lung but certainly it can be transmitted anywhere throughout the body and can activate anywhere throughout the body.

And so therefore extra pulmonary TB basically spans across the entire health care sector. We often think of tuberculosis being associated with respiratory or respiratory illness and I'll talk a little bit about this when I go into the diagnostics but in actual fact, we're seeing a lot more extra pulmonary tuberculosis then we ever did before. At St. Mike's we've seen several bladder TB's, renal TB's, we've seen bone and joint tuberculosis, as well Potts Disease which involves the spine. Certainly tuberculosis meningitis is an issue. We've also had cases in pregnancy and also transmission of congenital tuberculosis. And so it really does go across the gamut and needs to be thought of that way.

So I'm always asked the question, what are my chances of getting tuberculosis That's a favourite question amongst health care workers or when an exposure has happened or when they're working with a TB patient and it's never an easy answer and no one has a final answer for them. It really depends on a lot of different factors. It depends on ventilation issues, whether there is any ventilation, the duration of contact with the active case, how infectious was the active case and how susceptible is the host. I guess those are just primary principles of epidemiology.

I'm just going to talk a little bit about preventing the transmission of tuberculosis and hopefully hit on each one of those areas just a little bit. The main way to prevent the spread of tuberculosis in any health are facility is to ensure that there's a high index of suspicion and that the people working - the physicians and the nurses that are working in the facilities have tuberculosis on their list of differential diagnosis regardless of the discipline that they're in. I think that this is the biggest challenge, especially in developed countries where tuberculosis has not been an issue in the past. In the education system, even with new residents coming out, tuberculosis and the information about it either may be old or may not be necessarily taught in all of the different areas. And so I'm finding that even the infection control practitioners in our own facility have gone to amazing lengths to ensure that this is a huge index of suspicion.

Other ways to prevent TB is to have specific isolation policies for your facilities and making them very specific as to what does isolation, air born isolation mean and who can do it and who can take people off of isolation and what are the parameters around that. I can talk a little bit about that later on. Certainly in most facilities, what gets put in place for preventing transmission of tuberculosis will really depend on how many patients you see in your facility. You can go with a simple mask of which there are a whole variety across the board such as a Technol 2000 or there's 3M. The main goals around masks and the types of masks that you use is that there are effective filters to keep the organism out. Basically in that they will filter a small micron The tuberculosis organism that will infect could be anywhere from point five to five microns. They must fit well so that there's no leakage around and that they're comfortable.

Now I haven't provided this on your slides but Fennalli, it's Fennalli in 1997 Clinics in Chest Medicine volume eighteen, that whole volume actually is on tuberculosis and it's a wonderful. There's a wonderful article in there on personal respiratory protective devices and it literally goes from your powered air purifying filtration which looks like the big hoods that go over your head right through to your average mask for your hospital. It would really depend on the number of cases that you see as to which that you require. Certainly it talks about fit tests because each person's face doesn't fit the mask the same way. If you are working with a lot of active tuberculosis patients, certainly fit tests may be required for your staff. And I use this picture in your slides as an example of what not to use. This person has your average surgical mask on and that's just not appropriate. I see more people putting the surgical mask outside of respiratory prevention or respiratory isolation rooms and they shouldn't even be on the cart It's confusing to whoever is going in and out and they're not going to protect them.

The other components of preventing transmission are negative pressure rooms. The CDC in Atlanta recommends are six to eight air exchanges an hour and this is outside ventilation. There's a difference between negative pressure and negative balance .Negative balance can be re-circulated air and a true negative pressure room is vented to the outside. And by definition negative pressure is ninety percent of the air borne contaminates being removed within about a twenty to twenty-five minute period. And this, can be extremely expensive in your hospitals. Again, it really depends on how many patients you see. I know St. Mike's right now has about fourteen negative pressure rooms working but that's primarily because we see a fair number of cases. There are other filtration devices for your hospitals that are quite effective.

The hepa filter unit, hepa meaning high efficiency filtration devices, remove about ninety-nine percent of particulate, down to the size of point three microns in diameter. So they're certainly effective for tuberculosis. There are some issues around using these devices in your hospital, especially if they're mobile and your engineering department would have to be quite involved in it. They need to be stationary. They can't be mobile. If they are mobile then you have air filtration issues and air flow issues .There also has to be things in place in your hospital for bio filtration procedures such as when you're changing the filters. Bio hazardous policies and procedures, must be in place, primarily because the tuberculosis organism that is being filtered can live in these filters for extended periods of time and certainly when the filters are being moved, they're highly contaminated.

The other option for breaking the mode of transmission that's highly effective is UV lighting and I'm not going to talk a lot about each one of these except to say that the UV lighting has been shown in some, even old research studies to be quite useful. It's germicidal at about a hundred, I think it's nanometers. to two hundred and ninety. There has been some discussion around cataracts and skin irritation with using UV lighting but that's primarily with long exposure and direct exposure. Many of the UV lamps that are out now are placed at the top of rooms and are actually quite effective without any risk to people in the environment. Certainly we have found when we use it, we have to have policies and procedures around changing the UV lighting .Most of the manufacturers can provide you with that information.

I know that I sort of have skimmed over those and I will provide Peggy with some of the different articles that talk a bit about that. It really would depend on each individual facility as to which you could employ but this goes all the way from the cheapest to the most expensive which is negative pressure or retrofitting your room. I'm just going to go back to one of probably your most important components and that's education, triage and early diagnosis in your institution. There's been a lot of studies done on triage in health care facilities One of the ones that I think is probably most interesting to us, is Dick Memsy in Montreal. There's a couple of articles that he's done and his most recent one that was published in the American Journal of Respiratory Critical Care Medicine in 2002 is in the April issue volume 165.

They looked at about seventeen different Canadian hospitals and these were urban based and non urban based, some affiliated with teaching hospitals. They looked at things like mortality rates, delay in isolation, and delay in diagnosis and conversion of staff in these facilities and they found that the delay of diagnosis of one or more weeks was associated with a typical presentation. I'm going to talk a little bit about that because I'm going to talk about the diagnosis of tuberculosis and how it is that it's got to be in the differential diagnosis of everyone. But certainly the typical textbook presentation of tuberculosis cannot be what everyone relies on- the coughing for greater than three weeks. We certainly see in our own program that cough is a very late stage, especially in pulmonary TB There are many people who are completely asymptomatic and still grow bacteria on culture. The other thing that they found was that the delay in diagnosis happened in places that didn't see a lot of tuberculosis so they weren't thinking TB off the top and certainly that delay, increased mortality amongst their patients with TB. They found that there was more incidence of conversion amongst their staff which totally makes sense.

So just to quickly go over the textbook presentation of tuberculosis, it's a cough for greater than three weeks, fevers, night sweats, weight loss, hemoptysis, fatigue, shortness of breath, some chest pain. Like I said, these are textbook presentations and for the most part we're finding with our patients that tuberculosis is a very difficult disease. It can start to wake up and multiply and be active for a long period of time prior to them actually even feeling the symptoms. That, or they may have systemic disease and may not even realize that they're fatigued. Many of our patients have told us that after they started therapy, they can't believe how tired they were.

And so many people will not recognize their own symptoms for a long period of time. The other thing is in many of the populations, tuberculosis is often a disease of underprivileged people. We've certainly had outbreaks in our homeless population and so to determine symptoms such as coughs in groups of people who smoke a great deal is not a helpful symptom to be looking for. Weight loss, many of these people are under nourished. Ever the refugees that we're seeing coming into the country are severely undernourished and so asking them about whether or not they've had weight loss in the last year is a very non- specific symptom for many of them. The other thing is the presentations in extra pulmonary TB.

We have seen a lot of bladder tuberculosis., The delay in diagnosis of bladder tuberculosis has caused severe scarring and long term effects to the renal system. This is primarily because people will present with urinary tract symptoms and then will continually have their urine sent for CNS and not think tuberculosis CNS which is a completely different test to order. This results in the delay in diagnosis We're finding more and more that they may present with the symptoms for extra pulmonary TB but in many cases, they're pulmonary as well. We've seen it in orthopedics and in the emergency department They may not necessarily present with classic tuberculosis but it needs to be on the differential.

The other thing that I wanted to talk a bit about is chest x-rays. That's probably one of the best ways in the emergency department to pick up tuberculosis. Primarily classic tuberculosis is found in the apices of the lungs and you can see what we call old granuloma throughout the tissue. If a person has been infected with tuberculosis an important thing to recognize, and we're seeing more and more is that people are calling it old granulomatous tuberculosis. You cannot determine active disease by looking at a chest x-ray. You can't determine that it's old tuberculosis by looking at a chest x-ray. We have had more active cases diagnosed on sputum when the chest x-ray was called old granulomatous disease. And one of our protocols in our tuberculosis package is to encourage speeding testing along with the chest x-rays and in most cases regardless of what the chest x-ray is showing, we will ask for three consecutive morning sputum samples. We have been amazed at the number of people who have grown on just what is considered radiologically as old granulomatous disease.

The other thing we've found, with contacts of active cases, is that their chest x-rays are often called within normal limits or increased bronchial markings. Those increased bronchial markings are actually the early stages of tuberculosis. Another thing we've noticed in the program is that clinicians will look at a chest x-ray and say oh, it's a pneumonia in the lower lobes or it's a pneumonia in the bases of the chest x-ray. That's how common community acquired pneumonia presents. There has to be the realization that newly infected cases of TB will present with a pneumonia in their lower lobes. The other thing is that HIV co-infection does not present typically on chest x-ray. An HIV positive patient who has a low CD four count may have a completely normal looking chest x-ray because they can't consolidate in their lungs.

Another thing they can present with is perihilar fullness and the rest of the chest x-ray is normal or they can present in the bases of their chest x-ray or in the base lower lobes. So the clinical textbook presentation of tuberculosis is no longer what we can go from. There always has to be the index of suspicion and it needs to be married with epidemiology. So if it's a newly landed immigrant who is presenting for the first time with this pneumonia, tuberculosis should always be thought of. Chest x-rays are very good for screening but they need to be married with things like sputum.

Another thing that I hear a lot in clinical practice is:, well they're not coughing so they can't produce sputum. This is not the case. If the person is a smoker they can produce sputum in the morning and certainly many people can produce even a small sputum sample. If any of you have worked with the provincial health lab, their testing is phenomenal and even on the smallest sputum sample we can get a culture that will grow. You may not get a smear but you can certainly get a culture. And so in our program, if the person is not coughing or says they're not coughing, we still attempt to get sputum. Now depending on how many active cases you see, it will really depend on whether or not you're going to do sputum induction and that type of thing and I'm not really going to go into that a great deal. We do use it at St. Mike's primarily because we see a lot of cases, but it would really depend on your index of suspicion and the availability of regular saline induction in your facility.

I wanted to talk a little bit about sputum samples. We usually, as most of you know, send a sputum sample off for tuberculosis and the smear is usually back in about a forty-eight hour period. It really depends on whether your facility does the testing or whether you have to send it out to the provincial health lab. But it primarily tells you if you have mycobacterium in there. I think the important part that I like to speak about with the smear is that in an unconcentrated tuberculosis smear you have to have a hundred thousand acid fast bacilli per mil in order to get a scarce smear. If it's concentrated which is what the Provincial Health Lab does, you have to have about ten thousand acid fast bacilli per ml

The reason that I bring this up is that if you have negative smears, it doesn't necessarily mean that you don't have tuberculosis. It just means that your sample wasn't large enough . And we know that Dr. Bear out of Montreal has done a lot of research around this and we know that smear negative cases do transmit tuberculosis. So it's important to recognize that if there's a clinical suspicion on chest x-ray and the person's symptomatic, even if their smears come back negative, you should still be considering tuberculosis and you may want to go on to bronchoscopy or whatever. The amplified mycobacterium direct test is a genetic probe that tests the RNA of tuberculosis. And so it's only used at the Provincial Health Lab and it's used on smear positive cases.

So if your smear is positive, they basically do this test in order to determine whether it's TB or if it's one of the other atypical mycobacterium. They will use it on special request if you think that there's tuberculosis and your smears have come back negative. This is usually done in consultation with the technicians down there and it's done on special cases and it's not as sensitive as it could be if it was a smear positive. All samples are sent for culture and it can take anywhere from two to four weeks for that culture to come back. And then it's usually sent on for sensitivity testing after that. Some specimens culture better than others. When you're looking at extra pulmonary tuberculosis, this is where we run into a lot of problems with getting sensitivity and specificity.

Often times if a sample isn't taken properly or it's not sent specifically for tuberculosis CNS, you will get a regular CNS but you won't have TB and this is added to the delay in diagnosis If you don't get a decent culture and sensitivity, you're not, you're basically treating in the dark. For tuberculosis of the olden days when the four first assigned drugs worked well on them, that's fine. You could treat clinically and you were usually pretty safe. Now that we're seeing more and more drug resistance coming in from developing countries and certainly with multi drug resistant TB, if you start treating tuberculosis and you don't know what your culture and sensitivity is, you're running the risk of driving them further into resistance if they are a resistant case. And I can't stress enough the need to have really, really good samples and have them sent for appropriate testing. The other thing we know is that meningitis tuberculosis can be highly fatal The Provincial Health Lab is forever seeing fatal cases that occur primarily because enough of a sample hasn't been sent. And that or the cases that are actually infectious are taken off isolation because the sample hasn't been appropriately sent. I've put a few examples in your handout.

I think the rest of the slides about initiating treatment are fine. I won't really go into that a lot. The only thing that I really did want to talk a bit about is, if you have a patient who is put on isolation and they have a previous history of tuberculosis or they've been in contact with a case in a developing country that was on tuberculosis medication, in the back of your mind you should always be thinking, this person could be drug resistant tuberculosis. We're seeing a lot of drug resistance coming out of the developing countries primarily because drugs are not available like they are here in Ontario. They're either sold on the black market, or they may be sold at a cheaper price if they're expired and sometimes they're availability at different levels. And so patients will often take them for as long as they can afford to take them or at least until they feel better and then the medications are stopped.

There's also been a lot of studies in different countries, I know of one specifically out of India that did a poll of private practitioners across the country and found a hundred and forty different treatment regimes used by them. They're not following the World Health Organization's standard of treatment. And that's why we're seeing drug resistant tuberculosis coming rapidly out of these countries. And so if you have someone on isolation and they've been previously treated for tuberculosis in the past, even before you get cultures and sensitivities, you need to be thinking this could be drug resistant TB and there should be experts involved in this The person may need to be on isolation for a long period of time even if their smears are negative especially if you have a high index suspicion and that they have chest x-rays that are indicative of TB. Now how am I doing for time?

Peggy Swerhun: Maybe you could just speak for about ten more minutes.

Gene Wilson: Okay, all right. Now I'm just going to quickly talk a bit about isolation and removing isolation because this is a real issue for us in the health care facilities around when is it appropriate to remove isolation. For patients who are diagnosed with extra pulmonary TB, pulmonary tuberculosis needs to be excluded prior to removing someone from isolation. If the person has three negative smears and another diagnosis has been found then the person can be removed, especially if they're staying in hospital. If there's still a strong index of suspicion then the person should remain on isolation until tuberculosis is ruled out, primarily because if you're not going to treat for TB, if you're going to treat for some other diagnostic issue that's been found and you later find out that the cultures have grown, we do know that smear negative tuberculosis can transmit. And so that really needs to be considered when you're removing isolation.

If a person is found to have active tuberculosis, if they are fully sensitive to first spine drugs, I always hear two weeks of treatment and then you can remove isolation. This is really based on old research and it should be taken with caution from the perspective that if the person is smear numerous, if there's a possibility that there's laryngeal tuberculosis along with their pulmonary TB, this two week rule cannot be used. There needs to be at least three negative smears if the person is going to remain in an institution. If the person is going to be discharged out into the community and their smears are still positive, they should not be discharged out prior to a two week period and especially if they're being discharged home to people who are immune compromised or if there are small children in the home. Their discharge plan, no matter what should always be coordinated with the public health unit and or the directly observed therapy department depending on whether you have that in your specific areas.

If the person has had previous tuberculosis in the past and you don't have cultures, or if you have an active case of multi drug resistant TB, they should have three consecutive negative growth on culture meaning not their smears. Regardless of their smears they need to have three negative culture growths. We've seen a lot of multi drug resistant TB in our program and we partner with West Park Hospital for all of our multi drug resistant cases and many of them can be isolated for extremely long periods of time.

I'm just going to move on to speak just briefly on employee screening and I may get some questions around that. Certainly employee screening is essential for any health care facility that has long term residents or that have residents that are at risk for tuberculosis. Your employees and their conversion rates will let you know if you've got an index case that hasn't been diagnosed. But also for their own safety, staff need to know what their baseline skin testing is and certainly two step testing should be used if you're going to do serial testing in order to really determine whether or not you have conversion.

I've put a slide in here about BCG vaccine. BCG vaccine within health care workers should be disregarded. I probably don't have a lot of time to talk about the vaccination itself short of saying that if a person's been vaccinated repeatedly after the age of five or in adulthood, twenty-five percent of the time they can go on to have a lifetime positive vaccination or sorry, Mantoux skin test, However amongst health care professionals that have either worked in endemic countries or worked with high risk groups, you can't hang your hat on the fact that this is a reliable test result because of the vaccination. The other important thing is that this vaccine is not useful in pulmonary tuberculosis. It's used in children in order to prevent tuberculosis from going on to being meningeal or disseminated and it has not been proven to be useful for pulmonary TB. So the person can still be infected with latent tuberculosis in their lungs and will go on to activate. We know that ninety percent of the active cases in Toronto are foreign born many of which have been vaccinated in the past.

And so the BCG vaccine needs to be disregarded when you're reading the skin testing and people should be told about preventative treatment. The preventative treatment is still isoniazid for nine months. The hepatotoxic rate is not what it used to be thought and the thirty-five year cut off is now no longer used in the American guidelines and certainly in the Canadian tuberculosis standards as well. The thirty-five cut off is used in certain groups but in high risk groups it's not used. And hepatotoxicity is, in most people under the age of thirty-five less than one percent chance and so the risk benefit needs to be weighed out with the health care person. If a person is HIV positive, there are alternatives - faster, shorter regimes but they tend to have higher hepatotoxic rates. And that's it. I can take questions now.

Peggy Swerhun: OK.

Operator: Thank you. We'll open the lines for questions. If you have a question, please press one on your telephone keypad. If you are using a speaker phone, please lift the handset and then press one. If at any time you wish to cancel your question, please press the pound sign. Please press one at this time if you have a question. There will be a brief pause while the participants register for questions. Thank you for your patience. Once again if you have a question, please press one. And our first question is from Debbie Bruny from Group Health Centre. Please go ahead.

Debbie Bruny: Hi. Your presentation was excellent. Thank you very much for these opportunities. The question I have is many of our staff have been our employees for twenty years consistently. What are the recommendations that you would give. Naturally the baseline testing is done at each hiring but with your employees that have been here long-standing how frequent should test be completed? We have an outpatient facility, we do active procedures here but it's actually a nine to five operation. What would your recommendations be for our type of facility for testing?

Gene Wilson: It's a group health centre?

Debbie Bruny: That's correct. We're the model of Ontario that Romanow spoke of.

Jean Wilson: Excellent, wonderful. Along those lines there are guidelines for the regular testing that you should have and it really depends on how at risk your staff is. I know that, at least annually for people who are in contact with patients that are at high risk. I know that for many health care facilities and I think from what you're asking me, it's mostly an outpatient type area, it should be annually. For high risk groups it should be, say for example they're doing bronchoscopies or they're working in emergency departments say in downtown Toronto or they're working in tuberculosis clinics for example, it's a minimum of every six months that those people should be skin tested.

Debbie Bruny: Okay, thank you very much. I appreciate that.

Operator: Thank you. Our next question is from Penny McElray from Harton Health Care. Please go ahead.

Penny McElray: Yes, thank you. I was just looking at the bottom of page seven on our handout in your very last slide there, you say positive results, size isn't everything and also could you comment on that in particular with regard to BCG immunization. And also just comment briefly on the serology testing for TB.

Jean Wilson: Oh yeah, okay sure. I'd be happy to. The reason why I put that in there is when it comes to BCG testing This is in the Canadian Tuberculosis Standards and some of the research that's been done across Canada on BCG, Usually BCG if it is going to mount a response is often less than ten millimeters or around the ten millimeter mark. The reason I put this in that size isn't everything is that I will often get phone calls saying I have a patient in my office, they have a fifteen millimeter in duration blistering positive skin test. I need you to see them as soon as possible. This doesn't necessarily mean that they're active. It just means that they're mounting a response. They may have been previously active and so I often say well go through the usual steps of doing a chest x-ray, do your sputum and so on. The other thing is that HIV positive people or people who have just recently been in contact won't necessarily have a very big response but it doesn't mean that they're not active. And so that was sort of what I was saying around that.

Now the serology testing is new technology that is coming out. It is on the market in the United States and in Australia right now. It's sensitivity and specificity is still slightly under question but the basic to it is it's going to replace the man two skin test and it really does differentiate between the BCG vaccine and true infection. And so for many of us that are working in this area, we're pretty excited about the technology It's still in the testing process and like I said, there's some issues around sensitivity and specificity. It's not here yet but it's on it's way and that certainly will help and it'll also help with bringing people back for readings. People aren't great at coming back for their second reading and this will eliminate that as well. So it is sort of on the horizon. It's not here yet.

Operator: Did you have any further question Ms. McElray?

Penny McElray: Oh no, thank you very much, that's it. I appreciate your answer.

Operator: Our next question is from the location of Francis Esmond from the [inaudible] Care Centre. Please go ahead.

Francis Esmond: My question deals with negative pressure isolation rooms and whether, how you feel about an anteroom versus no anteroom for your negative pressure isolation room.

Jean Wilson: The experience that I have had with the negative pressure rooms and certainly the ones that have been designed at St. Michael's is that there is an anteroom associated with it and I think that that is a really useful design. I've seen negative, I can't say which is better to be honest and I don't pretend to be an engineer so I couldn't give you the specifics around that. As far as I'm concerned and this is my own personal opinion because people say to me, well we don't have negative pressure so we don't have isolation. Patients can be isolated in a single room period as long as they're isolated in a single room. Now yes, if it's re-circulated air or whatever the case is, you're going to need to leave that room empty for a period of time before you can put someone else in there but it's, when you have nothing else, it's probably the best that you have and then I guess you take your next step up to one without an anti room and then one with an anti room and I guess that that would be how I would rate it but I guess it depends on what you have. Does that answer your question?

Francis Esmond: Very helpful but, I guess we're kind of being pressured in some situations in infection control practitioners to kind of provide consultation around new construction or existing construction where you're redesigning and the only thing about the lack of an anti room, it doesn't lend itself to function as an isolation room in terms of storage location where probably your anti room does when you look at your need for personal protective equipment being used at the point of use or the point at which you're putting it on. So I just wondered if you had any guidelines in defense of the use of an ante room because they seem to be, architects are advising that you don't really need them as long as you have the proper amount of air exchanges. That was just, I just wanted your comment from that perspective.

Jean Wilson: Yeah, I know that the CDC does do some recommendations around negative pressure rooms and certainly I know that there are standards out now for negative pressure rooms. I can't really comment on which is better other than I agree with you. I think that the ante room is useful. We've been running into all kinds of engineering issues in our facility Functional issues, you know, you can't see the patient because you don't want to use the negative pressure room for negative pressure. How do you turn it off. If you turn it off, does it impact other rooms? All of these are engineering questions that I think we're going to end up struggling with and I know our infection control practitioners really work closely with the engineers to try to grapple with. And it really does come down to cost and space and availability as well. So all of those factors have to be taken into consideration unfortunately.

Francis Esmond: Thanks for your comment.

Peggy Swerhun: Julie, how many more questions do we have?

Operator: We have one more person queued up.

Peggy Swerhun: Okay, that will be it then, thank you.

Operator: Okay, thank you. The next question is from the location of Susan Grant from Almonte General Hospital. Please go ahead.

Susan Grant: Hello. Our hospital policy is that we do a two step test on all new employees and that's regardless of the thirty-five year age limit. Now we don't do it for serial testing, we use it as a base line. Is that satisfactory or should I discontinue doing that for anyone younger than thirty-five?

Jean Wilson: Oh okay, I'm sorry, I probably have confused the issue a little bit here so I'll just go back over that. It should be just baseline. In order to give you a true baseline, the two step needs to happen at baseline. After that, if you're doing serial testing on a yearly basis, you only need to do one skin test at that point and the thirty-five cut off was associated with isoniazid. If you're going to take preventative treatment, it used to be that you didn't take preventative treatment if you were thirty-five years of age or over and that was a standard in the Canadian tuberculosis guideline. That's no longer the case, especially if you've been exposed to an active case. We are recommending isoniazid to all health care professionals who are skin test positive. Does that help?

Susan Grant: Yes, thank you.

Operator: At this time we have no more questions registered. I would like to turn the meeting back over to you Ms. Swerhun.

Peggy Swerhun: Thank you. Jean Thank you for taking the time out from your busy schedule to speak to us today. I'm sure we all agree how informative it was. Thank you once again. And finally before we end I would like to remind you about our next teleconference. It will take place on the June the 24th [subsequently rescheduled to September 9] at 1:30. We will be presenting "How Safe are your Needles?" The speaker will be Carol Goldman from Sick Children's Hospital in Toronto. Please check our web site, osach.ca for details or contact the Ontario Safety Association for Community and Healthcare at 416-250-7444. Thank you very much. This concludes our presentation for today.