Gazetting vancomycin-resistant enterococci (VRE)

18 Apr 2005

Question No:  78  

Question

Name of the Person: Dr Tan Sze Wee, Nominated Member of Parliament

To ask the Minister for Health whether he will consider gazetting vancomycin-resistant enterococci (VRE) as a disease under the First, Second and/or Sixth Schedule of the Infectious Diseases Act.

Question No:  69  

Name of the Person: Dr Amy Khor Lean Suan, Member of Parliament for Hong Kah GRC

To ask the Minister for Health (a) if he will provide an update of the vancomycin-resistant enterococci (VRE) outbreak at SGH; (b) what is the source or cause of this outbreak; (c) what are the risks of this outbreak spreading to other hospitals; and (d) what precautions have been or will be taken to reduce the risk of the development of VRE or other outbreaks within and across the different hospitals and possibly even the polyclinics.

Question No:  66  

Name of the Person: Mdm Halimah Yacob, Member of the Parliament for Jurong GRC

To ask the Minister for Health what is the cause of the outbreak of the vancomycin-resistant enterococci (VRE) at the Singapore General Hospital and what measures have been put in place to prevent a future occurrence of such an outbreak.

Reply

Reply From MOH

Several members have asked about the VRE cases in the Singapore General Hospital. Let me assure members that VRE is not like SARS. 

All perfectly healthy people have billions of bacteria in their large intestines. Enterococci are examples of such bacteria. Normal healthy people also carry bacteria in their nose, mouth and skin. These usually harmless bacteria may occasionally cause infections like pneumonia (lung infection) or septicemia (infection in the blood). Such patients are then treated with antibiotics. Enterococci used to be always sensitive to the antibiotic, Vancomycin. But bacteria mutate and can develop resistance to a specific antibiotic. When bacteria become resistant to an antibiotic, a different antibiotic has to be used to treat infections caused by the bacteria. 

The first antibiotic to be used in the world was Penicillin. After many years of penicillin use, penicillin-resistant bacteria emerged. The same happened after years of use of Ampicillin and, more recently, Methicillin. Staphlycoccus aureaus - bacteria normally found on the skin which become resistant to methicillin is called MRSA. Not surprisingly, after many years of Vancomycin use, we now have enterococci bacteria that are resistant to Vancomycin - VRE. 

VRE was first reported in England in 1986 and hospital-acquired outbreaks have subsequently been reported in USA and Europe. In Singapore, VRE is still rare, with only a handful of cases reported in recent years. 

Very few patients actually fall sick because of VRE. Those who do tend to be patients with low immunity because of multiple medical problems such as renal failure, diabetes and cancer. In these patients the VRE may infect sites such as a wound or urinary tract. The enterococci infection is then treated with an antibiotic other than Vancomycin. Mdm Halimah and Dr Amy Khor asked for the source of the VRE cases in SGH. It is still being investigated. We may never know for sure. The bacteria could be bacteria that mutated locally or it could be bacteria brought into Singapore by healthy carriers who carried the bacteria in their large intestines. 

The vast majority of patients with VRE are healthy carriers of the bacteria without any symptom. There are no effective treatments for healthy carriers since these bacteria are normal to the large intestines. Hospitals use many antibiotics within the hospital premises and the bacteria that survive and lurk in the hospital setting tend to be those that have antibiotic resistance. In a non-hospital environment, the bacteria there tend to be the non-resistant type. So very often a VRE carrier in the hospital setting becomes VRE negative after being discharged. However, as this process may take some time, carriers can continue to shed VRE in their stools for many months. Hospitals have an interest to identify them so that should they be admitted to the hospital they can be isolated. This will reduce the risk of VRE spread. 

In the current episode, VRE was first identified by SGH on 9 March 2005 in a 75-year old patient with multiple medical conditions. Through screening his close contacts, SGH identified 5 other patients with VRE. At that point, SGH decided to screen all its inpatients with a view to identify the carriers so that they can be properly isolated. In parallel, SGH staff were reminded to step up good infection control practices such as mandatory hand washing after consulting with each patient and stricter compliance of the 2-visitor rule in the hospital. 

Mass screening of all the inpatients in SGH has so far identified 93 patients with VRE. Of these, only three were found to be infected, with clinical symptoms. They were patients with multiple chronic medical conditions. 

To minimize the spread of VRE to other hospitals, we have also reminded them to step up infection control procedures. At the same time, SGH shares with the other hospitals the list of their recently discharged patients so that they can be isolated and screened for VRE if they are admitted there. 

So far, one such patient has been admitted to NUH. NUH has since identified another case of VRE in a foreign patient, but this patient was not related to the SGH cases. 

Mdm Halimah and Dr Amy Khor asked what precautions have been or will be taken to reduce the risk of future occurrences of VRE cases in hospitals. This is best done through a combination of measures. First, there must be a rational usage of vancomycin. Second, there must be good surveillance for hospital-acquired infections. Third, there must be strict adherence to sound infection control principles such as prompt isolation of patients with infectious diseases, barrier nursing and hand washing. 

These are all good hospital practices which all hospitals should adopt. Like Penicillin resistant bacteria and MRSA, VRE may eventually become part of our bacterial landscape. If this happens, infections now treated with Vancomycin will have to be treated by other antibiotics. The greatest danger is bacteria that becomes resistant to multiple antibiotics. To minimize this risk, antibiotics must not be used indiscriminately. Doctors should use antibiotics only when indicated and patients should complete their course of antibiotics when it is prescribed to them. 

Dr Tan asked whether VRE should be gazetted under the Infectious Diseases Act. We see no need as VRE is not a disease like SARS. However it poses a risk to immune-compromised patients in hospitals. We have therefore included VRE as a target in their infection control programmes.