XDR-TB FACTSHEET

|

WORLD TB DAY 2007 Extensively drug-resistant (XDR-TB): the facts

What is XDR-TB? What is the medical defi nition of MDR-TB XDR-TB is the abbreviation for extensively drug- and XDR-TB? resistant tuberculosis (TB). One in three people in MDR-TB, or multidrug-resistant TB, is a specifi c the world is infected with dormant TB germs (i.e. TB form of drug-resistant TB. It occurs when the ). Only when the bacteria become active do TB bacteria are resistant to at least people become ill with TB. and , the two most powerful anti-TB drugs. XDR-TB is TB that is resistant to any Bacteria become active as a result of anything that fl uoroquinolone, and at least one of three injectable can reduce the person’s immunity, such as HIV, second-line drugs (, kanamycin, and advancing age, or some medical conditions. TB can ), in addition to MDR-TB. This defi nition of usually be treated with a course of four standard, or XDR-TB was agreed by the WHO Global Task Force “XDR-TB can develop fi rst-line, anti-TB drugs. on XDR-TB in October 2006. when second-line If these drugs are misused or mismanaged, How do people become infected with drugs are misused or multidrug-resistant TB (MDR-TB) can develop. XDR-TB? MDR-TB takes longer to treat with second-line People who are ill with pulmonary TB (i.e. TB of the mismanaged and therefore drugs, which are more expensive and have more , the site most commonly affected) are often side-effects. infectious and can spread the by coughing, become ineffective.” or sneezing, or simply talking, as this propels TB XDR-TB can develop when these second-line drugs bacteria into the air. A person needs only to breathe are also misused or mismanaged and therefore also in a small number of these germs to become become ineffective. Because XDR-TB is resistant to infected (although only a small proportion of people fi rst- and second-line drugs, treatment options are will become infected with TB disease). Sometimes seriously limited. It is therefore vital that TB control the bacteria are already drug resistant if they come is managed properly. from a person who already has drug-resistant TB.

TB is preventable and curable. FUND THE GLOBAL PLAN TO STOP TB.

WORLD TB DAY 2007 Extensively drug-resistant tuberculosis (XDR-TB): the facts XDR-TB FACTSHEET

|

A second way of developing MDR- or XDR-TB is It is vital that clinicians caring for TB patients are treatment, using a surgical mask, especially in when a patient’s own TB develops resistance. aware of the possibility of drug resistance and have closed environments with poor ventilation. access to laboratories that can provide early and This can occur when anti-TB drugs are misused accurate diagnosis so that effective treatment is The risk of becoming infected with TB is very low in or mismanaged. This happens when TB control provided as soon as possible. Effective treatment the open air. Overall, the chances of being infected WORLD TB DAY 2007 programmes are poorly managed, for example when requires that all six classes of second-line drugs are with XDR-TB are even lower than with ordinary TB patients are not properly supported to complete available to clinicians who have special expertise in because cases of XDR-TB are still very rare. their full course of treatment; when -care treating such cases. providers prescribe the wrong treatment, or the How can a person who already has wrong dose, or for too short a period of time; when How common is XDR-TB? ‘ordinary’ TB i.e drug-sensitive TB, avoid the supply of drugs to the clinics dispensing drugs We do not know at the moment, but XDR-TB is rare. getting XDR-TB? is erratic; or when the drugs are of poor quality. However, WHO estimates that there were almost The most important thing is for a patient to continue half a million cases of MDR-TB worldwide in 2004, taking all their treatment exactly as prescribed. How easily is XDR-TB spread? and MDR-TB usually has to occur before XDR-TB No doses should be missed, but this is especially There is probably no difference between the speed arises. important if the course of treatment is meant to of of XDR-TB and any other forms of be taken every other day: so-called “intermittent TB. The spread of TB bacteria depends on factors We also know that fi ndings from the only global treatment”. such as the number and concentration of infectious study carried out so far showed that in some places people in any one place together with the presence perhaps as many as 19% of MDR-TB cases were Above all, the treatment should be taken right of people with a higher risk of being infected (such in fact XDR-TB, but this is likely to be uncommon. through to the end. If a patient fi nds that side- as those with HIV/AIDS). Wherever second-line drugs to treat MDR-TB are effects are a problem, for example, the tablets make being misused, the possibility of XDR-TB exists. them feel sick, they should inform their clinician or The risk of becoming infected increases the longer Research is being carried out urgently to fi nd out nurse, because often there is a very simple solution. the time that a previously uninfected person spends more. in the same room as an infectious case. If they need to go away for any reason, patients How can a person become infected with should make sure they have enough tablets with The risk of spread increases where there is a XDR-TB? them for the duration of the trip. high concentration of TB bacteria, such as can The majority of healthy people with normal immunity occur in closed environments like overcrowded may never become ill with TB, unless they are Why have we never heard of XDR-TB houses, hospitals or prisons. The risk will be heavily exposed to infectious cases who are not before? further increased if ventilation is poor. The risk of treated or who have been on treatment for less than For some years we have seen isolated cases of very spread will be reduced and eventually eliminated if about one week. highly resistant TB around the world that we would infectious patients receive proper treatment. today call XDR-TB. All the drugs used against TB Even then, 90% of people infected with TB have been around for a long time. If they are not Can XDR-TB be cured or treated? bacteria never develop TB disease. This applies to used carefully, then resistance can develop. Yes, in some cases. Several countries with good XDR-TB as well as to “ordinary” TB. People with TB control programmes have shown that cure is HIV , however, in close contact with a TB It is only recently, as we carry out regular surveys possible for up to 50–60% of affected people. But patient, are more likely to catch TB and fall ill. of drug resistance in more and more countries, and successful outcomes also depend greatly on the with improvements in laboratory capacity, that these extent of the drug resistance, the severity of the The TB patients whom they meet should be cases are being reported in greater numbers. This disease and whether the patient’s immune system encouraged to follow good , for has led to the problem being more closely examined is compromised. example, covering their mouths with a handkerchief and given a name. when they cough, or even, in the early stages of

“WHO estimates that there were almost half a million cases of MDR-TB worldwide in 2004.” XDR-TB FACTSHEET

|

How do countries prevent XDR-TB? with antiretroviral drugs will likely reduce the risk of Countries can prevent XDR-TB by ensuring that becoming infected with XDR-TB, just as it does with the work of their national TB control programmes, ordinary TB. and all practitioners working with people with TB, is carried out according to the International How do I know if I have TB or XDR-TB? Standards for TB Care. Symptoms of XDR-TB are no different from ordinary WORLD TB DAY 2007 or drug-susceptible TB: a cough with thick, cloudy Is it safe to travel to These emphasize providing proper diagnosis and mucus (or ), sometimes with blood, for more places where XDR-TB treatment to all TB patients, including those with than 2 weeks; , , and ; drug-resistant TB; assuring regular, timely supplies and muscle weakness; ; and in some has been identifi ed? of all anti-TB drugs; proper management of anti-TB cases shortness of breath and . drugs and providing support to patients to maximize XDR-TB has been found in every region adherence to prescribed regimens; caring for XDR- If you have these symptoms, it does not mean you TB cases in a centre with proper ventilation, and have XDR-TB, but it does mean you must go and of the world, though it is still very rare. minimizing contact with other patients, particularly those with HIV, especially in the early stages People who are at most risk, if they before treatment has had a chance to reduce the infectiousness. “Symptoms of XDR- do come into contact with someone TB are no different with XDR-TB, are those with reduced Can the TB , known as the BCG immunity to infectious , such as vaccine, prevent XDR-TB? from ordinary or drug- The BCG vaccine prevents severe forms of TB those with HIV infection or other medical in children, such as TB . It would be susceptible TB.” conditions that can weaken a person’s expected that BCG would have the same effect in immunity. preventing severe forms of TB in children, even if see a doctor for a check-up. If you are already a they were exposed to XDR-TB, but it may be less patient with TB and you are taking treatment, if after effective in preventing pulmonary TB in adults, the a few weeks of treatment at least some of these It is also advised that such people should symptoms are not improving, you should inform commonest and most infectious form of TB. avoid high-risk areas where there are no your clinician or nurse. The effect of BCG against XDR-TB would therefore infection control measures in place. likely be very limited. New are urgently What should be done if a person has been in contact with a known or suspect case needed, and WHO and members of the Stop TB Air travel itself carries only very minimal Partnership are actively working on new vaccines. of XDR-TB? Anyone who has been in contact with someone risks of infection with TB of any kind. What is the link between XDR-TB and known, or suspected of having, XDR-TB should consult their doctor or a local TB clinic and be HIV/AIDS? Why in some places is XDR-TB Travellers with concerns about visiting so highly linked with or associated with screened to see if they have TB. This is most HIV? Are most people with HIV-TB now important if the person has any symptoms of TB. countries with XDR-TB, or other health infected with MDR-TB and XDR-TB? risks, should seek advice from their If they have a cough, they will be asked to provide a TB is one of the most common in people doctor, national authorities, or trusted living with HIV/AIDS – because so many people are sample of sputum, which will be tested for evidence already infected with TB bacteria. of TB. Several other tests will be performed in the travel web sites such as clinic, including a skin test and a . www.who.int/topics/travel. In places where XDR-TB is most common, people If TB is found, treatment will be started with the living with HIV are at greater risk of becoming drugs to which the person’s TB is most likely to infected with XDR-TB, compared with people respond. without HIV, because of their weakened immunity. If there is any evidence of infection with TB bacteria If there are a lot of HIV-infected people in these but without TB disease, preventive treatment may “Air travel carries places, then there will be a strong link between be given (the choice of drugs will depend upon the only very minimal XDR-TB and HIV. Fortunately, in most of the places known drug resistance pattern) or the person may with high rates of HIV, XDR-TB is not widespread. simply be asked to attend regularly for a check up. risks of infection with For this reason, the majority of people with HIV who develop TB will have drug-susceptible or ordinary TB of any kind.” TB, and can be treated with standard fi rst-line anti- TB drugs. For those with HIV infection, treatment Extensively drug-resistant tuberculosis (XDR-TB): the facts XDR-TB FACTSHEET

|

What risks do health-care workers face What is WHO doing to combat XDR-TB? with XDR-TB, particularly those who may First, WHO is ensuring that the health authorities be HIV-positive themselves? responsible for TB control receive accurate To protect health-care workers who may come into information about XDR-TB. contact with infectious TB patients, appropriate

“WHO emphasizes that WORLD TB DAY 2007 and strict infection control measures must be Second, WHO is emphasizing that good TB control implemented in health-care facilities at all times. prevents the emergence of drug resistance in the good TB control prevents fi rst place, and that the proper treatment of MDR- Health care workers are also encouraged to make TB prevents the emergence of XDR-TB. the emergence of drug sure they are aware of their HIV status so that they can avoid putting themselves at risk of exposure. This is completely in line with the new Stop TB resistance in the fi rst Strategy launched in March 2006. Third, WHO place, and that the proper How quickly can XDR-TB be diagnosed? is disseminating MDR-TB guidelines for national This depends on the patient’s access to health-care TB control programme managers published in treatment of MDR-TB services. If TB bacteria are found in the sputum, the May 2006 to help countries establish effective diagnosis of TB can be made in a day or two, but programmes to combat drug-resistant TB. prevents the emergence of this fi nding will not be able to distinguish between drug-susceptible and drug-resistant TB. Fourth, the WHO Stop TB and HIV departments are XDR-TB.” coordinating an international response through a To evaluate drug susceptibility, the bacteria need WHO Global Task Force on XDR-TB which met for to be cultivated and tested in a suitable laboratory. the fi rst time in October 2006. Final diagnosis in this way for TB, and especially for XDR-TB, may take from 6 to 16 weeks. To reduce the time needed for diagnosis, new tools for rapid TB diagnosis are urgently needed.

Latest information and regular updates

Latest information and regular updates on XDR-TB, and related TB issues, will be published on the WHO Stop TB web site at www.who.int/tb and on the Stop TB Partnership web site at www.stoptb.org

For more information please contact: Glenn Thomas [email protected] +41 79 509 0677

TB is preventable and curable. FUND THE GLOBAL PLAN TO STOP TB.

www.stoptb.org WORLD TB DAY 2007