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CDC Telebriefing Transcript
SARS: Infection Control Guidance for Households with SARS Patients
March 29, 2003
MODERATOR: Thank you for standing by. Welcome to the SARS update conference call.
DR. GERBERDING: Thanks for joining us for another update on the Severe Acute Respiratory Syndrome or SARS. What I'm going to do today is just give you a brief recap of where we are in the epidemic and then I will talk about some new guidance that CDC will be issuing today to help prevent the spread of this infection here in the United States.
I'd like to first begin, though, with just a reflection on some sad news that CDC received this morning. Dr. Urbani, who is the WHO physician investigating the outbreak in Hanoi, died of SARS that he acquired during his investigation. He was a very close colleague of ours and someone that we had worked closely with in both Hanoi and Thailand through the past several years, and we are very sad and our condolences certainly go to his family and his colleagues as well as our colleagues in the area who've been working with him over the past few weeks on this investigation.
The global epidemic continues to expand. Today, WHO is reporting 1,491 cases and 54 deaths, plus the 62 cases that we are reporting here in the United States.
As you know, the U.S. cases are constantly undergoing revision and updating as additional information about the patients is determined, so that number may change over time.
We continue to regard the new coronavirus as the leading hypothesis for the etiology of this condition. The evidence is mounting from a number of international laboratories, that this is indeed the case; but we are also exploring other potential viruses as are our collaborators, and we will keep you posted as we go forward on that part of the scientific investigation. A number of things are in progress, including sequencing of the whole virus genome, and we'll have more information on that, potentially next week or the week thereafter.
We are at a situation in time where we recognize that the disease is still primarily limited to travelers, to health care personnel who have taken care of SARS patients, and to close contact with SARS patients.
The affected travelers are those who have been in Hong Kong, in Hanoi, in Singapore, and in mainland China, for the most part.
We believe, based on what the investigations have shown us so far, that the major mode of transmission still is through droplet spread when an infected person coughs or sneezes and droplets are spread to a nearby contact. But we are concerned about the possibility of airborne transmission across broader areas and also the possibility that objects that become contaminated in the environment could serve as modes of spread.
Coronaviruses can survive in the environment for up to two or three hours ,and so it's possible that a contaminated object could serve as a vehicle for transfer to someone else.
In health care settings, we have already initiated guidance to protect against droplets, airborne and contact spread of this virus, and today we're issuing an update on how to protect people in homes of SARS patients.
We know that the individual with SARS can be very infectious during the symptomatic phase of the illness. We don't know how long the period of contagion lasts once they recover from the illness and we don't know whether or not they can spread the virus before they have the full-blown form syndrome.
But most of the information that the epidemiologists have been able to put together suggests that the period of contagion may begin with the onset of the very earliest symptoms of a viral infection, so our guidance is based on this assumption.
If we learn more or we learn something different as we go forward and intensify our investigations, we will of course update or change our guidance.
SARS patients are either being cared for in the home, or who have been released from the hospital or health care settings, and are residing in the home, should limit their activities to the home. They should not go to work. They should not go to school. They should not frequent public places until at least ten days after they are fully asymptomatic.
In addition, if they're coughing or sneezing, they should use common sense precautions such as covering their mouth with a tissue, and ,if possible, and medically appropriate, they should wear a surgical mask to reduce the possibility of droplet transmission from them to others in the household.
In addition, and very importantly, they should use good hand hygiene, and that means washing your hands with soap and water, or using an alcohol-based hand rub frequently, and particularly after any contact with body fluids.
For the people who are living in the household with the SARS patients, and who are otherwise well, there is no reason to limit activities at this point in time. The experience in the United States has not demonstrated spread of SARS from household contacts into the community and so we are not advising any restrictions on the activity of contacts at this point in time.
However, it's very important that contacts with SARS patients be alert to the earliest symptom of a respiratory illness. That may be fatigue, headache or fever, and the beginnings of the usual upper respiratory tract infection, and if they have any symptoms suggestive of an impending illness, they should contact a medical provider, alert them that they are a SARS contact, so that the health care system can advise them where to come and get evaluation, and prepare the delivery system to implement the appropriate infection control precautions so that others are not exposed in the health care setting.
Contacts with SARS patients should also of course use hand hygiene and use the appropriate surgical mask to prevent contact with droplets, if the SARS patient in the home is unable to wear a mask.
We also are updating our guidance to travelers. I think that the travelers at risk for SARS are those who have been in mainland China, in Hong Kong, in Hanoi and in Singapore.
However, we recognize that there are passengers who moved through these areas for brief periods of times and are arriving here in this country indirectly, after being in those countries, so right now we are meeting both direct incoming flights from the affected areas as well as passengers who are arriving from different regions and have passed through those areas en route.
The alerting is being expanded to include arriving passengers from China, from mainland China, and from Singapore at this point in time.
In addition, the alert extends the period of passenger monitoring to ten days. Previously it had been seven days but we are aware of some patients that may have a longer incubation period, and to be on the safe side, we want to make sure that they seek medical attention if they develop any symptoms within ten days of departure from one of the SARS regions of the world.
These travel alerts do not include passengers coming in from Canada. The epidemiology of the SARS in Canada is very different and there is not a risk from incoming travelers at this point in time.
WHO is not issuing any travel restrictions. We are not issuing any travel restrictions either, but WHO has also implemented procedures for screening passengers before they leave the country of SARS origin. They're asking countries to evaluate departing passengers for respiratory illnesses or other signs that could represent SARS. In part, this is because there are some early reports that passengers traveling with a SARS patients on board could be at risk for acquiring this infection, and we don't want to have any cases acquired during flight or during transfer on a ship or other vehicle.
So the travel alerting process that's already been in place, and actually we've issued more than 150,000 alerts, is being expanded and will be involving 23 ports of entry into the United States.
So let me just stop here and take questions and I'll take a caller on the phone first. Can we have the first call.
I don't have a caller on the phone. I'll take someone from the audience.
MODERATOR: Ladies and gentlemen, if you wish to ask a question, please press one at this time.
Okay. Our first question comes from the line of Miriam Falco with CNN. Please go ahead.
QUESTION: Hi. Can you hear me?
DR. GERBERDING: Yes. We can hear you now.
QUESTION: Excellent. I don't know what that was. First of all, thanks, again, for having this.
The Canadian health authorities have issued quite a restrictive quarantine, now expanding to a second hospital.
Why are you not issuing any quarantine? Is it because you can't or because the situation is not so dire?
DR. GERBERDING: Well, first of all, we have been in constant communication with Canadian health authorities and they are not actually issuing a quarantine. They are issuing a voluntary self-isolation policy which is slightly different than a regulated quarantine.
The main reason we are not taking this step right now, in this country, is because the epidemiology of our problem is very different than the outbreak that Canada is experiencing in Toronto.
Although I reported 62 cases under investigation here, two of those cases are in health care workers and there have been no further signs of spread in that particular cluster. Five cases have been in household contact and the rest of the cases have all been in travelers coming in from SARS areas.
So we are not experiencing any sign of community transmission at this point in time, but we are alert to it, we are monitoring potential contacts very carefully, and if we see evidence that our infection control measures are not containing spread within communities, then we will have to reconsider whether additional steps are necessary.
I'll take another question from the floor here.
QUESTION: I notice that you list mainland China but now Taiwan. How significant is the risk in Taiwan?
DR. GERBERDING: Taiwan is a country that is reporting cases and they are included in the travel advisory for incoming passengers.
A question from the telephone.
MODERATOR: Our next question comes from the line of Larry Altman with New York Times. Please go ahead.
QUESTION: Yes. Dr. Gerberding, given the fact that Hong Kong health officials now are reporting suspect cases from an apartment complex, large numbers, apparently spread by one or two infected individuals in that area, how do the United States guidelines take the possibility of airborne transmission into effect?
You touched on this just a moment ago but given the new news, could you elaborate on that.
DR. GERBERDING: Yes. The information that we're getting from Hong Kong does suggest that in at least one apartment complex there has been spread. We can't identify yet, to what extent the individuals in that apartment have had face to face contact with each other, to what extent they might have contacted contaminated environments in that facility or to what extent airborne transmission could play a role.
It's obviously something that we're concerned about and we're working hard to get that sort of information.
There are other clues that face-to-face contact is not always the only means of transmission. Right now, in this country, our infection control precautions in health care settings in homes appear to have limited spread of the disease, but as I said, we are monitoring very carefully and if we see evidence of airborne transmission or failure of our current guidelines to contain this, we will be willing and need to take additional steps.
A question from the audience.
QUESTION: Following up on the question about modes of transmission, you mentioned, when you began to speak, that there's some indication that coronaviruses may survive on surfaces for a while, so could you discuss any implications that might have, particularly for airplanes or vessels, anything like that, in terms of this infection.
DR. GERBERDING: Yeah. I'll ask Dr. Citron [ph], who's our expert in international travel, itches [?], and infection control, to see what he can tell us about this infection in planes and boats.
DR. CITRON: Thank you, Dr. Gerberding.
We have issued preliminary guidance on appropriate means for disinfection of commercial aircraft as well as very specific and more focused guidance for disinfection of an aircraft that might be used in a medical evacuation of a high-risk or critically-ill patient, and those are available on the Web.
Although there's a possibility [inaudible] spread, this is a virus that's routinely susceptible to commercially available, normal types of disinfectants that are used in hospitals, and that's basically what you'll see in that guidance. So there's not need for taking extraordinary measures or using extremely caustic or dangerous types of materials, but the routine types of disinfectants are available and the specifics are on the Web site announcement [?].
QUESTION: Just a follow up. To follow up. What about disinfection in the home? Do you have guidelines for that? Is it just a question of chlorine or--
DR. CITRON: I think it's the same kind of principles that are going to apply, you know, standard household disinfectant agents to clean surfaces and bathroom areas, and things that may have come in a lot of contact with a potentially-infected patient, ought to be adequate.
DR. GERBERDING: You know, any time we have a new disease there are always a lot of questions about disinfection in the home, and I think one of the themes that's been most helpful in the past as we've dealt with AIDS or other infectious diseases--to use common sense. Prudent housekeeping policies are appropriate for home hygiene under any circumstance and those certainly are appropriate when there's a new infectious disease as well. So the common sense measures that we take for sustaining cleanliness in the home and food safety, and so forth, are appropriate under these circumstances as well.
May I have a phone question, please.
MODERATOR: We have a question from the line of Anita Manning with USA Today. Please go ahead.
QUESTION: Hi. Thanks very much, Dr. Gerberding. Actually, one of my questions has already been answered, but I did wonder if you could talk a little bit more about what travelers are experiencing in terms of what the CDC is informing them of. What are you doing?
DR. GERBERDING: What we are doing when passengers arrive at the 23 ports of entry involved in this alerting process in the United States is delivering to the passengers at the time that they're disembarking a health alert card, a small card that we now have translated into six languages, that advises them to be alert of any evidence of fever or respiratory symptoms for the ten days after they've left one of the SARS countries. The card specifically mentions the countries of concern.
In addition, there's a second section of the card that is information to clinicians, so if SARS patient does seek clinical attention, the clinician understands, they bring the card in and it gives them the specific advice, provides them information on how to get more up-to-date information on SARS, and also how to contact CDC and the importance of reporting any known or suspect cases.
So it's a mechanism to remind people at the point of departure, that they've been in an area where they could possibly have come in contact with someone with SARS and that they need to be alert to the earliest possible symptoms, so that they can get care and protect others.
Can I have another phone question.
MODERATOR: We have a question from the line of Betsy McKay with Wall Street Journal. Please go ahead.
QUESTION: Hi, Dr. Gerberding. Thank you very much for holding this briefing.
I was just wondering if you could update us on treatments that are being used in the U.S. for SARS patients. I understand that you have not issued specific treatment guidance but I'm just wondering if there are any changes in treatment that are being used around the country over the last few days and if there are any particular anti-viral medicines, or therapies that are being used that may seem promising? Thank you.
DR. GERBERDING: CDC is working with FDA and NIHD and USAMRIID and others to try to identify drugs that might have activity against this coronavirus, but as of today we have no leading candidates on the shelf, that we could recommend for clinical treatment.
The patients in the United States are being treated according to the guidance that we've issued to clinicians as well as standard management for pneumonia, and that does include treatment empirically for other causes of pneumonia, because at the initial presentation this disease could easily be confused with other common things for which we do have specific therapy.
So clinicians are advised to have a broad differential, to initiate antibiotics, if that seems appropriate under the clinical circumstances, and as they learn more, and more diagnostic testing is done, to stop those unnecessary treatments if, indeed, the condition does seem to be most consistent with SARS.
We have no evidence, unfortunately, right now, that any specific anti-viral therapy, or steroid treatment, or other agents that are targeting this virus, are of any benefit to patients. We hope we'll learn more as we go but that is the status of clinical care today.
How about a question here.
QUESTION: Hi. Jim Carr with Reuters. Just a follow-up on the earlier comment you made about Taiwan, because as I understand it, the cards that you were talking about do not include Taiwan among the listed nations.
Does that mean that Taiwan is less dangerous?
DR. GERBERDING: Let me ask Dr. Citron to take this question. There's a couple points of confusion here.
DR. CITRON: Thank you. I think there is the potential for confusing the two strategies. The passenger alert cards, the yellow cards that disembarking passengers get, is our surveillance tool, to be alert to the earliest possible cases, and consequently it's broader. It lists those three countries, China, Vietnam and Singapore at this point, and we want to be able to detect the first case from any of those areas.
The guidance that goes up to outbound travelers, the travel advisory which recommends deferring nonessential or elective travel, that is focused on helping somebody judge whether they should go to an area of risk and it's based on a risk assessment from the data that we have available or a risk assessment because of the absence of information.
So our current understanding of the risk, of the cases in Taiwan, as well as Canada and Toronto, is significantly different and significantly more confined, and consequently there isn't evidence, at this point, to suggest people defer that travel to Taiwan as opposed to Guangdong Province, for example, where there's a community epidemic going on.
So the outbound is guidance to help you assess risk about where you're going. The inbound is a surveillance tool, so we can find all cases early, and act on them quickly, get them to health care and be isolated. I hope that clears that up.
DR. GERBERDING: So it's on the list.
Can I have a telephone question.
MODERATOR: We have a question from the line of Robert Bazell with NBC News. Please go ahead.
QUESTION: Hello, Dr. Gerberding.
Given what's happened in Hong Kong, and southern China, and given what's happened in Toronto, how concerned are you about the possibility of a community outbreak in the United States?
DR. GERBERDING: We are very vigilant about the possibility of spread. We recognize that there are at least some patients with SARS that are extremely efficient transmitters. We don't know to what extent all patients are particularly infectious but there are clearly some who appear to be very highly infectious, and, for example, in Hanoi where there was one patient who was a source for health care worker transmission and approximately 56 percent of the health care who had direct contact with the patient appeared to have acquired SARS.
So given that high degree of contagion and what we know about spread of cold viruses, I think we are very alert to the possibility that this could spread outside of the confined populations that I've mentioned, travelers to the affected areas, close household contacts, and health care workers. But we are not seeing that now and we are looking for it very closely.
So if we begin to appreciate that, we will have to expand our recommendations to be more inclusive of special protective measures for contacts.
I'll take another phone question.
MODERATOR: We have a question from the line of Hija Charapadeya [ph] from CBC Radio Canada. Please go ahead.
QUESTION: It's actually Pia. Dr. Gerberding, I'm wondering how would you characterize the situation in Canada, specifically in Toronto, now that we upwards of about 70 probably and suspected cases?
And as a follow-up, you said the epidemiology of SARS in Canada is very different. What do you mean by that?
DR. GERBERDING: In Canada, unfortunately, when the initial patients arrived with SARS, we did not yet appreciate the illness and we did not know that infection control measures were appropriate, so the earliest patients were not placed on the special isolation precautions that we're talking about now, generically.
I think that allowed the epidemic to get started there and to spread to more people before there was a chance to really intervene with appropriate infection control.
We are incredibly impressed with what Canada is doing and what the local health officials are doing in Toronto. I think they're airing on the side of caution. They're taking eery step that we could imagine would be appropriate given the circumstances that they're facing.
We also have a liaison from Canada here in our emergency operations center and are preparing to send one of our CDC staff to Canada to make sure that our information exchange is complete and that we are in close collaboration and are aware of the situations in both countries as they evolve.
So I think we are learning from Canada as we go and we are keeping a very close watch on the situation there.
Can I have another telephone question.
MODERATOR: Yes. We have a line from the question of Tom Maw [ph] with Los Angeles Times. Please go ahead.
QUESTION: Can you give us a brief overview of the evidence that now supports the idea that this is in fact a coronavirus.
DR. GERBERDING: I'll take a stab at that and I'll ask Dr. Hughes to chime in. Dr. Hughes is the director of the National Center for Infectious Diseases. The evidence comes from a convergence of many types of laboratory investigations ongoing in many of the laboratories that are part of the WHO collaboration, including CDC.
First, we have isolated the coronavirus
We have developed an antibody assay which detects antibodies to this new coronavirus with a high degree of specificity and I think very compelling, some of the patients who have negative antibody tests at the beginning of their illness, subsequently, in paired [?] serum have demonstrated new development of antibody within days after their infection occurred. So they are developing an immunologic reaction to this new coronavirus and that's really strong evidence of infection.
It doesn't necessarily mean the infection is a cause of the pulmonary infection or the respiratory symptoms, but, clearly, that's very solid evidence that disease is occurring, the body is responding to it, specifically, and I think that is a very important source of information, and I'll let Dr. Hughes add the breaking information about what's probably coming out of the lab today.
DR. HUGHES: Well, many laboratories here at CDC, as well as around the world, have been hard at work at this for some period of time. A week ago today, there were no antibody tests which could be used to diagnose this infection. It's a result of considerable hard work. We now actually have two antibody tests that look quite promising and seem to be reproducible in different laboratories, and among the things we're doing is working to get ready to transfer diagnostic testing capacity to public health laboratories around the country, so that before too long, I'm hoping that tests will be available much more locally.
I should also say that we know that laboratories in at least seven other countries now have evidence for coronavirus, looking like it plays an important role in causing this syndrome.
So the preponderance of evidence in support of coronavirus as the cause continues to mount.
QUESTION: You had mentioned the screening process that's going on at the ports in the various countries.
What about the United States? Is there any screening being done on ingoing or outgoing passengers?
DR. GERBERDING: Let me first just offer a point of clarification. The WHO just issued this advice to the involved countries and recommended some steps they should take for departing passengers and you can find that on the WHO Web site.
Since I'm not aware, at this point, how much implementation has occurred already, I think there are going to be some difficulties in getting this implemented at every airport, and that's why we are continuing to alert the arriving passengers from these areas, to make sure that they are included in our catchment.
What really is the situation here is that arriving passengers are alerted. If we have people who are travelling to those areas, we're not issuing an airport-specific alert but we are putting the usual kind of guidance that goes up on our Web site and, you know, it's actually our travellers Web site is the most frequently sought component of the CDC Web site, so we know that that is a common place where people go for information when they're traveling abroad, and travelers clinics would also have this information and advice as people go in and prepare for their vaccinations or whatever is out there, leaving for whatever travel they're taking.
So our approach is primarily alerting people on their way back home, or on their way to the United States from these areas, and secondarily, to issue the generic statement that if you're traveling to this region you may wish to defer elective travel until such time that we know more and can do a more thorough assessment of what risks are present.
We are not medically screening incoming passengers but if a passenger is identified as having illness on a plane or a ship, they are met by the health authorities in that state, in conjunction with the CDC officials, and they are evaluated and we have done that several times.
So if there is evidence of a symptomatic person, on arrival they are assessed, and if necessary, the other passengers are evaluated and they're monitored prospectively, to make sure that they haven't been exposed as they go forward through the incubation period.
A telephone question, please.
MODERATOR: We have a question from the line of John Kerry with Business Week. Please go ahead.
QUESTION: There have been sort of conflicting views of where we are in the epidemic, whether it's continuing to spread or under control, and it may vary as to what country you're in. I was just hoping you could sort of address the big picture here and say what you think about where we stand, and also what lessons have been learned so far about the ability of the public health infrastructure to respond to this sort of thing?, and again, that may vary by country as well, I would think.
DR. GERBERDING: Well, from the standpoint of CDC, I would say that we are very concerned about the spread of this virus, particularly in Asia. We recognize this as a epidemic that's evolving differently, in different geographies, but nevertheless, it is a respiratory virus, it does appear to be transmitted very efficiently, and what we know about respiratory viruses suggests that the potential for infecting large numbers of people is very great.
So we may be in the very early stages of what could be a much larger problem as we go forward in time. On the other hand, this is new, we don't know everything about it, and we have a lot of questions about the overall spread.
The patterns of transmission in the individual countries vary, depending on where the primary foci of transmission is occurring.
In Hong Kong, the situation is particularly alarming because we have several hospitals that are affected, and there are so many health care workers in each of these hospitals that could have been exposed or who are developing SARS, that there's already a multiplier in the community. Every health care worker has household contacts, those contacts, when they become ill, have had other exposures.
So we are very concerned about the speed and the amplification process in Hong Kong. On the other hand, the health officials there are taking extremely efficient and aggressive steps at this point in time to contain spread in that community, including closing schools and closing hospitals, and cohorting health care workers and patients.
So it remains to be seen whether or not those measures will attenuate the spread. The biggest unknown is of course what is going on in China and we are desperate to learn more about the scope and magnitude of the problem there, because that really I think will be the biggest predictor for where this will be headed over the next few weeks. Yes?
QUESTION: Returning to the issue of for how long patients are contagious, and whether there's an asymptomatic contagious state, could you discuss whether you've been able to start any studies yet and what sort of studies there are.
DR. GERBERDING: There are studies going on to try to define the period of infectivity or the timeframe in which an asymptomatic person could have the virus, not yet be sick and transmit it to someone else.
One of the important studies going on is to look at passengers who traveled in airplanes with SARS patients, and so already we have three separate cohorts of passengers who traveled on the same plane with someone we knew was incubating SARS or had SARS during their travel experience.
So far, those studies have not identified evidence of transmission before people become sick but the numbers are small and we can't draw any conclusions at this point in time.
Likewise, when we have the test that Dr. Hughes was talking about, the antibody test, we'll be able to evaluate household contact of patients and measure their antibody response to see whether or not they were exposed and actually didn't get the full spectrum of disease but had evidence of asymptomatic infection, and that will help us calculate the attack rate or the proportion of exposed people who actually develop infection.
These are fundamental aspects of understanding any epidemic and we are just in the early phases of getting those pieces of information pulled together from across the world.
The WHO has been incredibly helpful in supporting all of these collaborative efforts.
Let me take a telephone question, please.
MODERATOR: Our next question comes from the line of Elizabeth Cohen with CNN. Please go ahead.
QUESTION: Hi, Dr. Gerberding. I have two questions. The first one, I know it's very hard for you to be real specific about this but this is what has everyone freaked out, so I feel like I need to ask you because people are asking me.
Could, if you're in an elevator, on the other side of an elevator with someone who has SARS, could they spread it to you? If you're three steps behind in an escalator. If you're on the same step of the escalator. I mean, what kind of distance are we talking about, because people are really anxious about that.
DR. GERBERDING: You're breaking up a little bit but I think I caught your question, which is basically what is the risk from brief encounters, in public settings, of acquiring this from someone who has the illness, examples of the escalator or the elevator.
The bottom line is that we don't know but what we can tell from looking at the epidemiology and the patterns of transmission so far, there is not evidence, at least in this country, to suggest that those activities are posing any risk.
Concerns that I mentioned earlier focused on droplet transmission, so if you were in the elevator and an infectious person literally coughed on you, it's conceivable that you could acquire a respiratory infection, including SARS, through that mechanism.
On the other hand, most of the information suggests that fairly prolonged contact, on a face to face basis, is typical of the transmissions.
There are anecdotal reports, that we haven't confirmed yet, of much briefer contact. There's been a concern expressed about the potential for airborne or surface contamination in the apartment in Hong Kong, and these are all open questions that we are aggressively pursuing here.
So we will learn as we go and as we said from the very beginning, we are erring on the side of taking extra precautions because we can't be confident that we are offering the best protection without taking those kinds of steps.
In environments where those infection control precautions have been implemented, there's been a dramatic reduction in spread to health care personnel, so it is possible to contain the infection through these measures but we don't know if that will be a 100 percent effective and we don't know which of the measures is the most important at this point in time.
Can I have another telephone question, please.
MODERATOR: We have a question from the line of Larry Altman with New York Times. Please go ahead.
QUESTION: Yes. This is a follow-up question that I should have asked earlier, Dr. Gerberding. Are the new guidelines going to be on the Web site right now?
DR. GERBERDING: They are likely to be up as we speak. They were issued, they're out, they're in the process of being put out through the health alert network, and as soon as we can get the Web button pushed, they'll be up.
QUESTION: Thank you.
QUESTION: I was wondering if you could offer us three pieces of demographic data of related cases here in the U.S. The first would be how many of those cases are in the Chinese community; second, how many in New York? Third, which state has the highest incidence of SARS.
DR. GERBERDING: Let me see if I have my state listing with me. So I will check on that. I know I'm not going to be able to tell you the race and ethnic distribution of the case patients in the United States at this point in time.
In terms of today's assessment, we had three cases added to our list overnight and so I don't have them segregated, by state, on my documentation, but right now the largest number of patients are in California. That's not surprising since California is one of our largest states. But that's also a point of a lot of travel to Asia and so it makes demographic sense, that that would be an area where there would be perhaps an increased risk.
I think you would probably want to contact the state health department to get the latest update on that. We can get back to you after this with that information.
Let me take a telephone question.
MODERATOR: We have a question from the line of Kida McPherson with Star-Ledger. Please go ahead.
QUESTION: Thank you; thanks, Dr. Gerberding.
My first question was: Just could you please repeat the number of American cases. It broke up and I couldn't hear that number. My second question is: You mentioned at the very beginning of this briefing that Dr. Urbani of the World Health Organization had passed away.
I would think that he would have had access to, you know, the best knowledge about how to protect himself, so I'm wondering--unfortunately, did you learn anything? Was he exposed in a way that you hadn't expected? Is there any kind of insight into that?
DR. GERBERDING: Thank you. I would take your first question. There are 62 patients in the United States under evaluation for SARS right now.
Two of those are health care workers and five of them are contacts of SARS patients, household contacts of SARS patients.
With respect to the mode of transmission to Dr. Urbani, at this point I can't tell you the best hypothesis for that, but I will say that he is the person who went into the hospital where the affected patient was in Hanoi first. He was the first investigator to be there and he arrived at a time when infection control precautions were not in place, so there are opportunities for him to have been exposed before the contagion was recognized and the capacity to implement state-of-the-art infection control had been developed in that facility.
I'll just take one more question from the phone, please.
MODERATOR: The last question comes from the line of Miriam Falco with CNN. Please go ahead.
QUESTION: Hi. A couple more questions. Number one, do you have any more clues about why there was a 90 to 10 percent breakdown in severity of disease, really, that was mentioned either in the MMWR or in the WHO?
And will these tests that Dr. Hughes was talking about be able to be used to determine if all of these 62 patients are actual confirmed cases?
Or is this a lower type of test, just to see what it might lead to for treatments?
DR. GERBERDING: I'm sorry, I did not understand your first question.
QUESTION: Well, it was either in the MMWR or the WHO report, that 90 percent of the patients get sick but then they recuperate. Ten percent of the patients have a severe illness and why is there such a difference in the cases? If you know anything about it.
Could it be that there might be other viruses involved as well?
DR. GERBERDING: Certainly, there could be other cofactors involved such as viruses or underlying illness, but this is just atypical pattern for any infectious disease. If you get pneumococcal infection, many people have completely asymptomatic. Some people get a mild disease and some people have a full blown, very, very severe illness from the infection.
So this is a typical pattern for respiratory illnesses, not something that we're surprised about. In fact if there's any good news in SARS right now, it's that the majority of patients do appear to recover and that the death rate is actually lower than what we see with epidemic influenza, about 3.5 percent of the patients have died from the illness. That is still a tragic occurrence for the people who are affected, and their families, and I would never mean to minimize it. But it is fortunate that it is not even more severe.
With respect to the issue of the diagnostic test, no, as Dr. Hughes said, we have only had this antibody for about a week, and so the fact that we've come this far so far means that there's still work to do to really know is it sensitive, in other words, does it pick up every case? and is it specific? Is it negative when somebody doesn't have SARS?
So we've got to do the validation and one way of doing that is to use the test in the people that we're highly confident have the condition and compare the results to people with intermediate probability and then those that we're sure have something completely unrelated, and that will give us some basis for assessing the reliability of the test, and that will help us then know whether or not we can use it to rule in or rule out SARS in the majority of people that we're dealing with.
So there's a lot of work to be done very fast but I think it's a remarkable achievement. Dr. Hughes and his team at CDC as well as the WHO collaborating investigators, should be applauded for the scientific rigor and the speed with which they have been able to accomplish so much in so little time.
Thank you for being here today and we look forward to updating you as we learn more.
This page last updated March 29, 2003
Department of Health and Human Services