Control of carbapenemase-producing Enterobacteriaceae outbreaks in acute settings: an evidence review

BACKGROUND

In recent years, infections with carbapenemase-producing Enterobacteriaceae (CPE) have been increasing globally and present a major public health challenge.

AIM

To review the international literature: (i) to describe CPE outbreaks in acute hospital settings globally; and (ii) to identify the control measures used during these outbreaks and report on their effectiveness.

METHODS

A systematic search of MEDLINE and EMBASE databases, abstract lists for key conferences and reference lists of key reviews was undertaken, and information on unpublished outbreaks was sought for 2000-2015. Where relevant, risk of bias was assessed using the Newcastle-Ottawa scale. A narrative synthesis of the evidence was conducted.

FINDINGS

Ninety-eight outbreaks were eligible. These occurred worldwide, with 53 reports from Europe. The number of cases (CPE infection or colonization) involved in outbreaks varied widely, from two to 803. In the vast majority of outbreaks, multi-component infection control measures were used, commonly including: patient screening; contact precautions (e.g. gowns, gloves); handwashing interventions; staff education or monitoring; enhanced environmental cleaning/decontamination; cohorting of patients and/or staff; and patient isolation. Seven studies were identified as providing the best-available evidence on the effectiveness of control measures. These demonstrated that CPE outbreaks can be controlled successfully using a range of appropriate, commonly used, infection control measures. However, risk of bias was considered relatively high for these studies.

CONCLUSION

The findings indicate that CPE outbreaks can be controlled using combinations of existing measures. However, the quality of the evidence base is weak and further high-quality research is needed, particularly on the effectiveness of individual infection control measures.

Suicide by gases in England and Wales 2001-2011: evidence of the emergence of new methods of suicide

BACKGROUND

Increases in suicide deaths by gassing, particularly carbon monoxide poisoning from burning barbecue charcoal, have occurred in many parts of East Asia and resulted in rises in overall suicide rates in some countries. Recent trends in gas poisoning suicides outside Asia have received little attention.

METHODS

We analysed suicides by gassing in England and Wales (2001-2011) using national suicide mortality data enhanced by free text searching of information sent by coroners to the Office for National Statistics (ONS). We conducted specific searches for suicides involving barbecue charcoal gas, helium, and hydrogen sulphide. We analysed coroners' records of eight people who used helium as a method of suicide, identified from systematic searches of the records of four coroners.

RESULTS

Gassing accounted for 5.2% of suicide deaths in England and Wales during 2001-2011. The number of gas suicides declined from 368 in 2001 to 174 by 2011 (a 53% reduction). The fall was due to a decline in deaths involving car exhaust and other sources of carbon monoxide. There was a rapid rise in deaths due to helium inhalation over the period, from five deaths in the two year period 2001-2002 to 89 in 2010-2011 (a 17-fold increase). There were small rises in deaths involving hydrogen sulphide (0 cases in 2001-2002 versus 14 cases in 2010-2011) and barbecue charcoal gas (1 case in 2001-2002 versus 11 cases in 2010-2011). Compared to individuals using other methods, those suicides adopting new types of gas for suicide were generally younger and from more affluent socioeconomic groups. The corones' records of four of the eight individuals dying by helium inhalation whose records were reviewed showed evidence of Internet involvement in their choice of method.

LIMITATIONS

We were not able to identify the source of carbon monoxide (car exhaust or barbecue charcoal) for over 50% of cases.

CONCLUSION

Increases in helium inhalation as a method of suicide have partially offset recent decreases in suicide by the use of car exhaust. Public health measures are urgently needed to prevent a potential epidemic rise in the use of helium similar to the recent rises in charcoal burning suicides in East Asia.