Antibiotics susceptibility patterns of bacteria isolated from American and German cockroaches as potential vectors of microbial pathogens in hospitals

Essential Oils in Urban Insect Management-A Review

The allures of city life have culminated in the rise of urban populations resulting in conditions that promote the establishment of certain insect pests. Globally, the public health significance of these urban insect pests is enormous, ranging from billions of dollars to loss of lives. Most chemical insecticides no longer provide the anticipated level of control, and significant insecticide resistance has been reported. Therefore, there has been a spike in interest for alternatives to conventional insecticides. Among them, natural products from plants such as essential oils (EOs) and essential oil components (EOCs) have enjoyed the most attention owing to widespread reports of efficacy and toxicity even against insecticide-resistant urban insects. Yet, there is no comprehensive synthesis on the extent and impact of the management of urban insects using EOs or EOCs. Such a review is highly relevant since it provides a means to assess the extent of progress made, shortfalls, limitations, and prospects. More so, we hope it can be used to make informed decisions and develop relevant policies reliably. We present the ranges of insecticidal effects of EOs, EOCs, and commercially available EO-based products from laboratory and field studies. Finally, we discuss the gaps in our knowledge and prospects for the sustainable use of EOs.

Bacteria associated with cockroaches: health risk or biotechnological opportunity?

Abstract

Cockroaches have existed for 300 million years and more than 4600 extant species have been described. Throughout their evolution, cockroaches have been associated with bacteria, and today Blattabacterium species flourish within specialized bacteriocytes, recycling nitrogen from host waste products. Cockroaches can disseminate potentially pathogenic bacteria via feces and other deposits, particularly members of the family Enterobacteriaceae, but also Staphylococcus and Mycobacterium species, and thus, they should be cleared from sites where hygiene is essential, such as hospitals and kitchens. On the other hand, cockroaches also carry bacteria that may produce metabolites or proteins with potential industrial applications. For example, an antibiotic-producing Streptomyces strain was isolated from the gut of the American cockroach Periplaneta americana. Other cockroach-associated bacteria, including but not limited to Bacillus, Enterococcus, and Pseudomonas species, can also produce bioactive metabolites that may be suitable for development as pharmaceuticals or plant protection products. Enzymes that degrade industrially relevant substrates, or that convert biomasses into useful chemical precursors, are also expressed in cockroach-derived bacteria and could be deployed for use in the food/feed, paper, oil, or cosmetics industries. The analysis of cockroach gut microbiomes has revealed a number of lesser-studied bacteria that may form the basis of novel taxonomic groups. Bacteria associated with cockroaches can therefore be dangerous or useful, and this review explores the bacterial clades that may provide opportunities for biotechnological exploitation.

Key points

• Members of the Enterobacteriaceae are the most frequently cultivated bacteria from cockroaches.

• Cultivation-independent studies have revealed a diverse community, led by the phyla Bacteroidetes and Firmicutes.

• Although cockroaches may carry pathogenic bacteria, most strains are innocuous and may be useful for biotechnological applications.

Household cockroaches carry CTX-M-15-, OXA-48- and NDM-1-producing enterobacteria, and share beta-lactam resistance determinants with humans

BACKGROUND

This study was designed to investigate whether household cockroaches harbor cephalosporin-resistant enterobacteria that share resistance determinants with human inhabitants. From February through July 2016, whole cockroach homogenates and human fecal samples from 100 households were cultured for cephalosporin-resistant enterobacteria (CRe). The CRe were examined for plasmid-mediated AmpC, ESBL, and carbapenemase genes; antibiotic susceptibility patterns; and conjugative transfer of antibiotic resistance mechanisms. Clonal associations between CRe were determined by multi-locus sequence typing (MLST).

RESULTS

Twenty CRe were recovered from whole cockroach homogenates from 15 households. The prevalence of households with cockroaches that harbored CRe, AmpC- (based on phenotype, with no identifiable blaAmpC genes), ESBL-, and carbapenemase-producers were 15, 4, 5%(2 bla_{CTX-M-15/TEM-1}; 1 bla_{CTX-M-15/TEM-4}; 1 bla_TEM-24; 1 bla_SHV-4) and 3%(2 bla_NDM-1 genes and 1 bla_OXA-48 gene), respectively. Overall, 20 CRe were recovered from 61 fecal samples of inhabitants from all 15 households that had cockroach samples positive for CRe. Of these, 5CRe (1 per household) were positive for ESBLs (bla_TEM-24, bla_TEM-14, bla_{CTX-M-15/TEM-4}, bla_SHV-3, bla_{CTX-M-15/TEM-1}) and none carried AmpCs or carbapenemases. From 4% of households, the pair of cockroach and human CRe shared the same sequence type (ST), clonal complex (CC), antibiogram, and conjugable bla gene sequence (house 34, E. coli ST9/CC20-bla_TEM-4; house 37, E. coli ST44/CC10-bla_CTX-15/TEM-4; house 41, E. coli ST443/CC205-bla_CTX-15/TEM-1; house 49, K. pneumoniae ST231/CC131-bla_SHV-13).

CONCLUSION

The findings provide evidence that household cockroaches may carry CTX-M-15-, OXA-48- and NDM-1-producers, and share clonal relationship and beta-lactam resistance determinants with humans.

Contamination of Cockroaches (Insecta: Blattaria) by Medically Important Bacteriae: A Systematic Review and Meta-analysis

Cockroaches have the potential to disseminate bacteria in their environments and therefore a systematic review and meta-analysis was conducted to assess the state-of-the-art of our knowledge regarding bacterial contaminants of cockroaches. At least 78 bacterial species and 42 genera from 24 families and 11 orders of bacteria were reported to have contaminated cockroaches. At least 61, 42, 12, 13, 7, and 16 bacterial species have contaminated Blattella germanica (L.) (Blattaria: Ectobiidae), Periplaneta americana (L.) (Blattaria: Blattidae), Blatta orientalis (L.) (Blattaria: Blattidae), Diploptera punctata (Eschscholtz) (Blattaria: Blaberidae), Periplaneta fuliginosa (Serville) (Blattaria: Blattidae), and Supella longipalpa (F.) (Blattaria: Ectobiidae), respectively. Blattella germanica is the most commonly contaminated cockroach species, with the widest bacterial species diversity that threatens human health, followed by P. americana. Cockroach bacterial contaminants may result in the dissemination of opportunistic or pathogenic infections, particularly nosocomial and foodborne infections. One-way analysis of variance (ANOVA) revealed significant differences between bacterial contaminant species of cockroaches, species of cockroaches with bacterial contaminants, cockroach body part surfaces from the point of view bacterial contaminants and countries of cockroach infested with bacterial contaminants (P < 0.05). This statistical analysis indicates that the bacterial contaminants of the external cockroach body parts are potentially more harmful than from internal surfaces, and secondly, the bacterial contaminants of cockroaches in hospital environments are potentially more harmful than from other human environments. The survey indicated that the bacterial contaminant species of cockroaches appear to be mostly multiple drug resistant. The challenges of cockroaches as being potential vectors of pathogenic or opportunistic agents of human infections are discussed.

Pest Cockroaches May Overcome Environmental Restriction Due to Anthropization

Our species have altered their surroundings since its early dispersion on Earth. Unfortunately, thanks to human-modified habitats, several pest organisms such as domiciliary insects have expanded their distributions. Moreover, pest-related microorganisms may also be aided by anthropization. Pest cockroaches are globally distributed and capable of carrying several diseases. We explored if urbanization may buffer environmental conditions allowing pest insects to expand their distribution. Specifically, we suggest that human settlements may generate suitable microhabitats for synanthropic cockroaches, helping them to survive and establish with disregard to overall climatic restrictions. To test this idea we studied the distribution of pest cockroaches spanning the length of Chilean territory. Chile, along its 4270 km length north to south extent, is a country offering a formidable sampling of Earth's climatic diversity accompanied by dense urbanizations. We studied entomological collections and spatially analyzed pest cockroach distribution found in Chile and discovered that synanthropic cockroach populations are consistently concentrated near most urban developed zones of the country and not limited by overall temperature. Furthermore, health-concern pest cockroach species were widely distributed in Chilean territory, found even in its most southern urban centers as well as Easter Island. Therefore, these disease vectors could exist even in isolated and extreme climatic zones as long as urbanization provides the adequate microhabitat. We discuss the need for further research in order to assess if these distributions can be extrapolated to the pathogenic strains these pest insects may be carrying as reported in other regions of the planet.

Infestation of cockroaches (Insecta: Blattaria) in the human dwelling environments: A systematic review and meta-analysis

Periplaneta americana, Blatta orientalis, Blattella germanica and Supella longipalpa are the most common worldwide cockroaches that mentioned in the "22 common pest" or "22 dirty" species named as "group I". They are able to infest any type of buildings. A meta-analysis review was conducted between January 2015 and July 2016 on any literature published about infestation of cockroaches. Scientific reports and papers about infestation of cockroaches and relevant topics were collected from various specific scientific websites such as PubMed, Web of Science, ScienceDirect, Springer, Elsevier, Scopus, and Google Scholar. About 271 scientific reports and papers were collected and after a preliminary review, 63 were selected to become part of the detailed synthesis review and meta-analysis. Results showed that the global world mean infestation trend of cockroaches, and B. germanica and P. americana cockroach species ranged 49.0-55.0, 40.0-70.0 and 60.0-70.0%, respectively suggests that their infestation trend are increasing. The global world mean infestation of cockroaches, and B. germanica and P. americana cockroach species were 52.3, 55.2 and 65.4, respectively. There was a significant difference between the global world mean infestation of cockroaches and P. americana cockroach species (P=0.019). The global mean infestation trend of cockroaches in the human dwelling environments and world ranged 55.0-65.0 and 50.0-70.0%, respectively suggests that their infestation trend are increasing. The global world mean infestation of cockroaches in the human dwelling environments and world were 60.4 and 57.7%, respectively. Although some factors affect the infestation of cockroaches and the sanitation and quality structure of the buildings are also being improved. While as present study reveal that the globally the world infestation trend of cockroaches are being increased and recent studies also indicate that the prevalence of asthma has increased dramatically over the decades suggest that infestation of cockroaches can directly affect the development of asthma.

First Report of German Cockroaches (Blattella germanica) as Reservoirs of CTX-M-15 Extended-Spectrum-β-Lactamase- and OXA-48 Carbapenemase-Producing Enterobacteriaceae in Batna University Hospital, Algeria

Here we report the isolation of extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Enterobacteriaceae from German cockroaches caught in the burn unit of Batna University Hospital in Algeria. Nine of 12 isolates harbored the blaCTX-M-15 ESBL gene. One Enterobacter cloacae isolate belonging to sequence type 528 coexpressed the blaOXA-48, blaCTX-M-15, and blaTEM genes. Our findings indicate that cockroaches may be one of the most dangerous reservoirs for ESBL and carbapenemase producers in hospitals.