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Journalism - some examples


Here are some examples of my journalism. If you are seeking contributed pieces, please contact me.

Can coronavirus be transmitted in vape vapor?

This is an example from October 2020

Aerosols and vapor generated by electronic substance delivery systems could participate in the dissemination of the virus in the close proximity of coronavirus infected vapers, according to new research. 

The spreading of the current coronavirus of concern is foremost by virus-laden droplets that are expelled at speaking, coughing, sneezing, or breathing. One of the primary means to protect an uninfected person from someone who is infected is to maintain a physical distance of two metres or more. Contact should, however, be short because the risk continues where contact is prolonged given the ability of the virus to spread via aerosols.

Such aerosols can spread over greater distances. It is possible that exhaled smoke or vapour from vaping products can enhance this mechanism. Whether the coronavirus can be spread through exhaled vapour of an infected person will probably depend on level of mucus and saliva in the vapour and the force at which the vapour is exhaled (such as if the vapour is accompanied with a cough). 

The issue has been raised by microbiologist Tom McLean (of the environmental body the NanoTera Group), who has said vapers could be spreading the virus with the aid of vape clouds. McLean told The Glasgow Times newspaper: "We're all used to walking down the street now and it's one cloud followed by another cloud, followed by another cloud....Blowing vapour out is as good as someone spitting in your face." According to Dr. Winickoff, director of pediatric research at the Tobacco Research and Treatment Center at Massachusetts General Hospital, it is important to alert the public and particularly young people that vaping may exacerbate the risks of spreading the coronavirus. 

In support of this, Professor Linda Bauld, the Bruce and John Usher Chair of Public Health at the University of Edinburgh, has said it is: "entirely plausible’ that the coronavirus could be transmitted through vape clouds . To look into the dynamics, a research group from China used numerical simulations of a typical respiratory aerosol in a turbulent jet to simulate exhaled vapour. This was based on conditions designed to replicate ambient velocity, temperature, and humidity. 

The study also found that with rising ambient humidity the survival time of small droplets increased. These opinions and findings are not shared by all researchers. For example, health experts from the University of Mexico are of the view that "Exhaled vapor from an infected vaper is a negligible contagion factor: it can spread very few virus carrying droplets, as much as blowing or mouth breathing." However, no research is provided to back-up this statement. 

A further dissenting voice comes from the UKVIA, which is the largest trade body representing the vaping sector in the U.K. The group has asked for an end to what it considers to be misinformation about vaping. Other opinions are currently neutral. For example, the U.K. government states: "it is currently unknown what effect vaping may have on susceptibility to severe disease if you are infected with COVID-19." Due to the absence of evidence, the British government further states: "we recommend that vapers avoid exhaling clouds of vapour in the presence of others."

Why masks work and time to end the debate?

How effective are face masks? The body of evidence in favour of masks continues to grow. In this week’s Essential Science, we consider a diverse array of different literature that looks at mask wearing in different contexts. 

It may not have been high on Donald Trump’s agenda, but the medical consensus is firmly siding on wearing masks in the context of the coronavirus pandemic. Despite this, there remains a large number within the global community who are unconvinced. 

Yet reducing disease spread requires not one, but two things. The first is with limiting contacts of infected individuals, which can be achieved through social distancing. The second measure is to reduce the transmission probability per contact. With this second measure, the use of the facemask is important.

Before leaping into the evidence for masks, it is important to point out that Masks, depending on the material and design, filter out a majority of viral particles, but not all. Another factor is the type of mask, especially given that masks differ in their maximum internal leakage rate limit. The common surgical masks, and the type easiest to get hold of, are designed to protect against larger droplets or particles. Given that the SARS-CoV-2 virus is small, with a diameter of 60–140 nm, then the standard masks cannot provide a complete barrier. While N95 masks will protect the wearer from 90 percent of airborne particles, that could be carrying the coronavirus. In contrast, surgical masks are 67 percent effective in protecting the wearer.

However, surgical masks are effective in terms of protecting people from large droplets and sprays. It is as larger droplets that most viral particles are ejected from an infected person, via these larger sized pathogen-transporting droplets and aerosols. What most scientists think According to an article on the Nature website, by Lynne Peeples, the scientific consensus is firmly with facemasks saving lives during the pandemic. Peeples writes: “research shows that they cut down the chances of both transmitting and catching the coronavirus, and some studies hint that masks might reduce the severity of infection if people do contract the disease.” Wearing masks works A recent study, studying an array of data, finds that weekly increases in mortality (based on statistics normalized for per head of the population) were four times lower in places where masks were the norm, compared with other regions (especially regions where mask wearing did not represent government advice).

The study is titled “Association of country-wide coronavirus mortality with demographics, testing, lockdowns, and public wearing of masks.” In the study multivariate analysis was used to consider mask wearing together with an array of different factors. These factors included: age, sex, obesity prevalence, temperature, urbanization, smoking, duration of infection, lockdowns, viral testing, contact tracing policies, and public mask-wearing norms and policies The case of the hair stylists Some evidence about the effectiveness of masks arises from a report that looked at two hair stylists who were diagnosed with COVID-19 are working in a salon. Although they went home after and subsequently infected other members of their family, no one who was being beautified in the salon become infected (based on those who agreed to be tested). Interestingly, A total of 139 clients were directly serviced by stylists A and B from the time they developed symptoms until they took leave from work, with no cases of infection being reported. 

This case appears in a publication issued by the CDC, titled “Absence of Apparent Transmission of SARS-CoV-2 from Two Stylists After Exposure at a Hair Salon with a Universal Face Covering Policy - Springfield, Missouri, May 2020.” Protest to survive? A second case study looks at protestors. One question that springs to mind during any marches or rallies that occur during COVID-19 is whether those taking part, in close contact and who do not wear masks, are at a greater risk

For example, at one rally in the U.S. for Black Lives Matter, where the participants had the sense to wear masks, the rally did not trigger spikes in infections among those present, see: “Black Lives Matter Protests, Social Distancing, and COVID-19 NBER Working Paper 27408”. However, at a summer camp in Georgia, where moat present did not adorn masks, the infection rate was relatively high. The summer camp case is presented in “SARS-CoV-2 Transmission and Infection Among Attendees of an Overnight Camp - Georgia, June 2020.” Reducing infection rates Perhaps the most important of the new research relating to make usage, which comes from the University of California, is the finding that masking reduces the dose of virus a wearer might receive. The impact of this is infections that are milder or even asymptomatic. This now appears to be supported by virologic, epidemiologic and ecologic evidence.

The study is published in the Journal of Internal Medicine and it is titled “Masks Do More Than Protect Others During COVID-19: Reducing the Inoculum of SARS-CoV-2 to Protect the Wearer.” Mask shortages Where there is a shortage of masks, then the focus should be foremost with mask-wearing by infectious people (so-termed "source control"), rather than mask-wearing by susceptible people. 

Call for a global disinfectant standard

The time has come for industry and disinfectant manufacturers to set out guidelines for evaluating products appropriate for pharmaceutical cleanrooms.

Maintaining environmental control in a pharmaceutical manufacturing environment is dependent on the facility’s cleaning and disinfection programme, which requires the selection of the appropriate disinfectants, their proper application, and an assessment of their capability to inactivate or kill bacteria and fungi.

Disinfectants have a variety of properties that include spectrum of activity, mode of action, and effectiveness. Equally, the chemicals are often categorised into groups based on their chemical nature, spectrum of activity, or mode of action. Effectiveness is assessed through disinfectant efficacy testing.

A problem faced by users, is the array of different (and often contradictory) standards together with differing and often unrealistic, acceptance criteria. For those working in pharmaceuticals and healthcare, a global approach applicable to these sectors is required.

The Life Sciences division of Ecolab has developed a new approach to meet this need, and the key aspects of this useful approach are discussed in this article.

Why disinfectant efficacy testing matters

Qualification of a disinfectant is demonstrated through performance testing to show that the disinfectant is capable of reducing the microbial bioburden found in a pharmaceutical manufacturing area. The primary tests are divided into suspension tests, surface tests and field trials.

The field trial is the final piece of the qualification jigsaw and it is essentially an assessment of environmental monitoring data; the suspension and surface tests are generally taken to be the core disinfectant efficacy tests.

Of these two, the surface test is the most robust. While supplier data can be taken for suspension tests, undertaking some form of surface test is normally expected of the user. The surface test is the one required by regulatory agencies, as set out by the Pharmaceutical Inspection Co-operation Scheme (PIC/S) in document PI007.

There are differences in the approaches between North America and Europe, and with the guidance issued by professional bodies. This array of approaches creates confusion

With the surface test, representative manufacturing surface samples are inoculated with a selection of microbial challenge organisms. A disinfectant is applied to the inoculated surfaces and exposed for a predetermined contact time, after which the surviving organisms are recovered.

The number of challenge organisms recovered from the test samples (exposed to a disinfectant) is compared to the number of challenge organisms recovered from the corresponding control sample (not exposed to a disinfectant). Successful completion of the validation qualifies the disinfectant evaluated for use.

In setting out to perform surface testing, it stands that there is no ‘universal’ approach to disinfectant efficacy testing. There are differences in the approaches between North America and Europe, and with the guidance issued by professional bodies. This array of approaches creates confusion for the user and also leads to inappropriate levels of testing. Some of these differences are drawn out below.

Global differences in efficacy tests

Both the EU GMP and the US FDA regulations mention the importance of the pharmaceutical manufacturer evaluating the efficacy of the disinfectants used, and various standards are available to guide the microbiologist through this process.

The user can choose from CEN (European Committee for Standardization); AOAC (Association of Official Analytical Chemists International) or ASTM (American Society for Testing Materials) standards (North America); or draw on guidance from a professional body or non-mandatory compendia, such as USP 40-NF35 Chapter <1072>. These standards and guidelines are contradictory and not totally suitable for the pharmaceutical cleanroom.

Differences include recommended organisms (often different types of organisms); the surface coupon sizes; permitted inoculum volumes; test recovery method; whether interfering substances are present; whether physical action is permitted (wiping); starting microbial challenge levels; and log reductions (4 to 3 logs). In addition to the standard panel of prepared cultures, organisms isolated from the facility should also be tested as per regulatory expectations.

It is important to note these standards are multi-industrial (including industries where high levels of microbial contamination would be expected). The lack of a universal approach leads to user and regulatory confusion, and often the consequential outcome of over-specifying the acceptance criteria.

The time has come for industry and disinfectant manufacturers to set out a new solution to this regulatory issue that is appropriate to pharmaceuticals. One such approach has been proposed by Ecolab Life Sciences through the Validex Programme.

Validex: The Ecolab approach

In drawing a framework for what such a global standard will look like, Ecolab reviewed the essential factors that need to be captured within a disinfectant efficacy test targeted for classified cleanrooms and associated controlled-but-not-classified (CNC) areas. Here the most important factors are:

  • The microorganisms used should reflect those commonly recovered from pharmaceutical facilities
  • The target reductions should reflect the levels of contamination typically seen within pharmaceutical facilities
  • The surfaces challenged with microorganisms should be representative of the surface finishes found in pharmaceutical cleanrooms
  • Contact times should reflect operational conditions
  • Application of mechanical action
  • Soling (surface cleanliness)

Representative microorganisms

The test panel of organisms should be populated with microorganisms commonly found in pharmaceutical facilities. Examples of representative organisms, highlighted by Ecolab for the pharmaceutical context are:

  • Staphylococcus aureus
  • Staphylococcus epidermidis
  • Micrococcus luteus
  • Escherichia coli
  • Pseudomonas aeruginosa
  • Burkholderia cepacia
  • Bacillus subtilis
  • Candida albicans
  • Penicillium chrysogenum
  • Aspergillus brasiliensis

These organisms are reflective of what is carried on operators, associated with water systems, linked to equipment transfer, or representative of common fungi. Plus, efficacy studies need to be supported from organisms isolated from the manufacturing environment, especially where such organisms are different to the above list. Factors to consider when selecting such organisms include:

  • Ensuring that all process cleanrooms are reviewed (from Grade A to Grade D).
  • Review data from water systems used to dilute disinfectants.
  • Ensure that the review covers a sufficiently long period of time to account for variables such as seasonal variation.

Such reviews should be conducted periodically, for example, annually.

Appropriate microbial challenges

With target populations, the criteria should be reflective of the regulatory recommended permitted maximum levels of microorganisms while also being sufficiently high to show a logarithmic reduction. The highest microbial surface level permitted in an EU GMP Grade D cleanroom, for instance, is 100 CFU. Under this requirement, there is little value using a starting challenge inoculum of one million cells or more and seeking a 6-log reduction.

A further reason for setting realistic challenges is because test organisms will be grown as healthy laboratory cultures and challenged while in the logarithmic phase of growth. Such organisms are typically more resistant than organisms within the cleanroom environment, which are often not growing and subject to external stress factors. Hence, it is important to set appropriate and realistic acceptance criteria so that products are not being unnecessarily or overly challenged. On this basis, recommended challenges under the Ecolab proposal are shown in Table 1.

The above acceptance criteria are equivalent to those recommended in USP <1072>.

When preparing microbial cultures, starting inocula should be sufficiently high in order to compensate for in-test dilutions and to account for some loss of viability during drying. Ecolab recommends 1.5 x107 to 5.0 x 107 for bacteria; 1.5 x106 to 5.0 x 106 for fungi and bacterial spores.

Representative surfaces

Prior to initiating disinfectant efficacy validation, a comprehensive survey of the materials comprising the room surfaces (floors, walls, windows) and equipment (stainless steel, acrylic, polyvinyl chloride, and so on) present in the facility which could potentially be exposed to the disinfectant should be conducted.

In terms of selecting common surfaces, the Ecolab approach is to draw up a matrix where users are advised to assess the following factors in order to select ‘worst case’ surfaces:

  • Hydrophobicity
  • Surface roughness
  • Potential for chemical interaction at surface
  • Prevalence
  • Contamination risk (such as with horizontal surfaces are a greater risk than vertical; plus, those surfaces that are frequently touched)
  • Proximity to product, areas where critical activities are performed

From this, common surface types may include:

  • Vinyl
  • Aluminium
  • Epoxy coated flooring
  • Glass
  • Stainless steel
  • PVC
  • Polyurethane coated walls
  • Plexiglass
  • Acrylic
  • Polycarbonate
  • Gloves

The size of the test coupon should be standardised (you can get better recovery from a smaller coupon).

Ecolab has reviewed the essential factors that need to be captured within a disinfectant efficacy test

Contact times

There is little value in evaluating disinfectants targeted to kill vegetative microorganisms with contact times for longer than 5 or 10 minutes. One reason is practical; a busy pharmaceutical facility will not be wanting to wait for 60 minutes every time a disinfectant is applied.

Another reason is scientific; given the rapid air changes found in many cleanrooms and clean air devices treated surfaces will dry quickly and no surface will remain ‘wet’ for a prolonged period, triggering the need for repeated application. Therefore, relatively short contact times should be targeted.

Mechanical action

The method of application for the most disinfectants to a surface is either by spraying and wiping or mopping (commonly described as involving ‘mechanical action’).

There are clear advantages with this since wiping can increase the efficacy of disinfection and physically removes particulates, soiling materials (and residues), and microorganisms (microorganisms that are detached from surfaces are easier to kill). The activity of wiping also ensures a controlled delivery of the disinfectant onto the surface. Therefore, the inclusion of mechanical action is an important part of the disinfectant efficacy evaluation.


Disinfectant standards outline challenges with soiling. The application of additional soil (to create ‘dirty’ conditions) should not be necessary when evaluating disinfectants in a pharmaceutical facility since disinfectants should be being applied to clean surfaces.

Making sure a global disinfectant efficacy standard happens

With Ecolab having set out some clear, sensible and reproducible criteria for the evaluation of disinfectants for use in pharmaceutical facility cleanrooms, it is now time for industry and manufacturers of disinfectants to come together to ensure that such an approach becomes the de facto approach for the industry.

This can happen through users developing protocols along the lines recommended; having supplier recommending the revised criteria; and, most importantly, engaging with regulators to present the scientific arguments behind the approach and seeking universal acceptance of what needs to become a global standard for disinfectant efficacy testing as applied to pharmaceuticals.


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