Cot mattresses as reservoirs of potentially harmful bacteria and the sudden infant death syndrome

Abstract

Cot mattress materials were investigated as potential reservoirs of bacteria in relation to the sudden infant death syndrome (SIDS). The sleeping position of the infant significantly influenced bacterial population density of cot mattress polyurethane foams (p<0.0000001) and their covers (p<0.004). Staphylococcus aureus was isolated at significantly higher frequency (p<0.03) from the infant's head region of cot mattress materials. Significantly higher bacterial population densities (p<0.001) were associated with polyurethane foams from non-integral mattresses (exposed polyurethane foam), when compared to those from mattresses completely covered by polyvinyl chloride (integral type mattress). The frequency of isolation of S. aureus from polyurethane foams from non-integral mattresses was also significantly higher (p=0.03) than from foams from the integral type. The following factors were significantly associated with increased frequency of isolation of S. aureus: from the polyurethane foam, previous use of non-integral mattresses by another child (p=0.03 for all sample sites, p=0.01 for torso region); from the covers, sleeping in the prone position (p=0.003 head region, p=0.001 torso region). Prone sleeping was also significantly associated with increased bacterial population levels (p=0.01) and increased frequency of isolation of Escherichia coli (p=0.02) from the torso region of cot mattress covers. These findings could explain some recently identified risk factors for SIDS associated with type and previous use of cot mattresses. Clostridium perfringens was isolated at very low frequency and Streptococcus pyogenes was not isolated from any cot mattress materials tested.

Used cot mattresses as potential reservoirs of bacterial infection: nutrient availability within polyurethane foam

“…The frequency of isolation of bacteria capable of degrading colloidal PU was not significantly (P > 0AE05) influenced by mattress type (integral or nonintegral), age or previous-use by another child. In the apparent absence of such influences, the relevance of the presence of PU-degrading bacteria within infant mattresses to bacterial population densities within the PU foams (Sherburn and Jenkins 2004a) remains unresolved. The isolation of S. aureus strains with PUdegrading capability from nonintegral used infant mattresses (n = 3), may have relevance to the identified higher frequency of isolation of this species from nonintegral used infant mattresses (Sherburn and Jenkins 2004a) and to prolonged survival of this species on PU foam (Jenkins and Sherburn 2005).…”

“…In the apparent absence of such influences, the relevance of the presence of PU-degrading bacteria within infant mattresses to bacterial population densities within the PU foams (Sherburn and Jenkins 2004a) remains unresolved. The isolation of S. aureus strains with PUdegrading capability from nonintegral used infant mattresses (n = 3), may have relevance to the identified higher frequency of isolation of this species from nonintegral used infant mattresses (Sherburn and Jenkins 2004a) and to prolonged survival of this species on PU foam (Jenkins and Sherburn 2005). We have shown previously that S. aureus, Streptococcus pyogenes and Escherichia coli can utilize aqueous extractable components within PU foam of unused infant mattresses as sole sources of carbon and nitrogen for growth (Jenkins and Sherburn 2005).…”

“…Tappin et al (2002) subsequently showed that routine use of an infant mattress previously used by another child is also associated with an increased risk of SIDS. We have previously reported significantly higher bacterial population densities to be associated with PU foams from mattresses not completely covered by PVC (Sherburn and Jenkins 2004a). Mattresses with exposed PU foam, and previous-use of these types of mattresses by another child, were also shown to be significantly associated with increased frequency of isolation of S. aureus from cot mattress PU foams (Sherburn and Jenkins 2004a).…”

“…We have previously reported significantly higher bacterial population densities to be associated with PU foams from mattresses not completely covered by PVC (Sherburn and Jenkins 2004a). Mattresses with exposed PU foam, and previous-use of these types of mattresses by another child, were also shown to be significantly associated with increased frequency of isolation of S. aureus from cot mattress PU foams (Sherburn and Jenkins 2004a). Cot mattresses harbouring relatively high levels of naturally acquired toxigenic bacteria have been shown to increase density of viable bacterial in the air above the mattress surface, and are considered to pose a relatively high risk of infection of the infant's respiratory tract through inhalation of viable toxigenic bacteria (Sherburn and Jenkins 2004b).…”

Biomethylation of Arsenic, Antimony and Bismuth

“…The outcomes of this research initiated a change in focus in relation the link between SIDS and cot mattresses, from volatile gases to the presence of harmful bacteria. There is now substantial evidence to implicate Staphylococcus aureus as an aetiological agent in SIDS and its variable presence in different types of cot mattresses provides a mechanistic explanation for several risk factors for SIDS [116][117][118][119].…”