Diagnostics & Treatment

Treatment

Figure 1: Draft of the BaKillus Nasal Spray

The human nasal mucosa is the main ecological niche of Staphylococcus aureus residing in human beings. S. aureus adheres to the mucosa and the epithelia of the anterior nares[http://dx.doi.org/10.1016/S0966-842X(01)02254-5]. The goal of BaKillus is to decolonize and kill S. aureus within the interior nasal areas. Other methods of decolonizing S. aureus have already shown to reduce the risk of infections with S. aureus subsequently to open surgery[http://dx.doi.org/10.1056/NEJM200101043440102][http://dx.doi.org/NEJMoa0808939]. Nonetheless those current preventive measures include efforts towards screening patients that will receive surgery in order to avoid overusage of antibiotics. BaKillus resembles an alternative possibility as it will only produce antibiotics in response to the actual presence of Staphylococcus aureus. It is therefore possible to apply BaKillus as an preventive application without need for screening and unneccessary usage of antibiotics at the same time.

To maintain a cheap and easy-to-use application we decided to create a specialized nasal spray. The general functionality is the same as for any common nasal spray for medical applications, so no pre-experience is needed to use our BaKillus Spray. The characteristic of Bacillus subtilis to build heat resistant spores, that can be stored dryly gives the spray a very high life period as long as the spores are not activated (learn more about Bacillus subtilis). To make sure the BaKillus spores do not get activated too early we developed an additional chamber associated to the pump mechanism. This chamber in the shape of an open ring (Fig. 1) will be sealed by a two component lamination. One layer of plastics will tighten the chamber while a cellulose layer will add stability and make the lamination perforable. BaKillus spores will be enclosed within the chamber. In the assembled product On the first pumping, the lamination will be perforated by being pushed onto the cutting edge ring. The spores will become free and mix into the second chamber below. Inside this chamber, sterile defined media as well as an oxygen-enriched atmosphere will be presented to the spores. Application of the activated BaKillus spray to the nostrils will be identical to common nasal sprays.

Usage of the BaKillus Spray is described below:

• Start spore activation by pushing down the pumping mechanism once to break the lamination seal.
• Mix the spores and the medium by shaking vigorously.
• Incubate at 37 °C for 2 hours to activate the spores to the BaKillus cells.
• Apply BaKillus Spray to each nostril every 2 hours. Reactivated Spores can be used for 20 hours before they will yield useless.
• Recycle the Nasal Spray.

For the future we emphasize a rent-and-return system for the nasal spray itself in combination with a more dispersed distributional network. For more information about future application scenarios please visit our Collaboration with the Rathenau Institute page.

For a second application, using a similar principle we invite you to visit our collaboration partner's Wiki from Groningen about the Lacto Aid System.

Diagnosis

Pathogen-identification diagnostic tool:

Problem:

Current tests to identify S. aureus are PCR-based detections of pathogene-specific genes. Theoretically, a PCR result could be obtained within three hours, whereas it takes around seven hours in practice. However, PCR-based methods are error-prone. Therefore, verification by a molecular biological test is recommended. Current biological tests (e.g. coagulase) require a time-consuming (18-24h) culturing step. Based on the test results, rapid and strict hygiene rules, e.g. separation from non-infected persons, seem to be very effective to lower the spread of health-care associated MRSA.

Here, we suggest an alternative strategy that can potentially facilitate the current diagnosis procedure.

The BaKillus S. aureus diagnosis tool:

We are planning to develop a ready-to-use diagnosis tool for point-of-care testing by the professional staff in hospitals, pharmacies or medical offices (see Fig. 2). A smear of a patient into a BaKillus-reporter culture could be enough to verify the presence of S. aureus within 0.5-2 hours (just limited by the time for BaKillus spore germination and reporter gene expression). This culture-independent detection could be precautionary used by patients of certain risk groups. The fast result would enable health-care institutions to directly start subsequent treatments/hygiene measures just after arrival of the patient and thus contact between infected and non-infected patients and therefore the spreading of multi-resistant pathogens could be lowered.

Figure 2: Basic concept of the BaKillus diagnostic tool. BaKillus spores are stored separately in a self-contained device. About one hour before use, spores and medium are mixed and incubated for the germination of the spores. The sample of a patient (e.g. a smear) can be applied into the culture and after about 30 minutes the result can be analysed (e.g. pigment production or luminescence as a reaction to pathogens)

Table 1: Discussion of the BaKillus diagnostic tool.