Right now as things stand in South Africa and around the world in terms of the available information regarding COVID-19, there are still many gaps and unknowns in the public domain about the treatment and handling of the coronavirus.
People often overestimate their own healthiness and doing so can have negative consequences when employees or students decide to continue to go work or go to school while sick. Depending on the work or school environment and the level of their illness, a sick employee or student can infect co-workers, classmates, customers, teachers and the general public.
The introduction of a screening system and protocol to prevent infected individuals from spreading pathogens have shown to have a real, positive impact on public health and in containing the spread of infections.
SCHOOL SCREENING GUIDELINES
The screening control guidelines for pupils returning to school on 1 July have been set by government as follows:
- Staff must be on duty to ensure learners adhere to social distancing norms
- Learners and teachers must have their temperatures checked and if normal proceed to a screening point
- The screening point will have prepopulated registers – containing name, surname, grade physical address, learners cell phone numbers, next of kin contact nos, temperature and response to the screening questions
- Officials managing the screening point will then screen the learner and record the temperature and response onto the register
- If the screening questions indicate there are no risks and the temperature is below 38 Deg C the learner can proceed to enter the building
If the screening or the temperature indicates a risk, the learner or teacher must be accommodated in an isolation room / area until the next of kin arrive. The next of kin must be advised to immediately seek medical advice
Screenings to be completed 3 x per day
The inherent issue with the above process is that person(s) completing screening processes or taking relevant temperatures need to be well informed and trained in the correct methods of performing this critical protocol.
WHAT IS SCREENING?
We need to firstly understand that we are not taking body temperatures but skin temperatures, and the best place to take this reading is from the inner canthus of the eye (tear duct) as this is the hottest part of the body, and is as per ISO Screening Standards. ISO are standards that are internationally agreed by experts. Think of them as a formula that describes the best way of doing something. Or we can take a reading on the temporal artery on the forehead. i.e. between the eyes where the unibrow would meet or just above, on the forehead.
The reason why we take from these two areas is that they are normally the hottest areas of the body and research has ascertained that there is a direct correlation between the canthus of the eye (skin) and body temperature.
WHAT IS THE CORRECT TEMPERATURE SCREENING RANGE?
The devices that will most likely be used to complete temperature screening of their pupils, staff and customers will be contactless IR Thermometers due to their cost. There are other available technologies which use thermal cameras (featured in our product section) which have pre-set algorithms that do screening automatically, they are however more expensive, and many organisations will not be able to afford this more sophisticated technology.
Most IR Thermometer’s range is between 32 deg – 42.5 deg Celsius. Most IR Thermometers also have a surface and body setting – ensure you correctly set these devices for ‘body’.
To ensure that correct readings are attained bearing in mind that the statutory alarm or threshold has been set by government at 38 deg C, hence most IR thermometers alarm setting have been set at 38 deg C. What is very important to note however is that all testing must be completed in an environment that has a constant temperature of between 23 – 27 deg C. This will be challenging for South Africa going into winter this cannot and will not be achieved in the mornings where our ambient temperatures can drop as low as +- -3 deg C and hence a vital floor in setting the fever threshold at 38 Degrees.
WHEN IS THE OPTIMAL TIME TO SCREEN INDIVIDUALS FOR COVID-19?
Understanding that there is a direct relationship between skin temperatures and ambient external temperatures, necessary adjustments of devices need to be assessed.
Many people using IR thermometers have already asked the question ‘why in the mornings are we getting “LO” on our thermometers – the answer is simply, the skin temperature has dropped below what the thermometer can read, as well as people possibly not understanding where readings can and should be taken from.
Therefore in the mornings many people taking temperatures will often get a “lo” reading or temperatures between 32.5 – 33.8 deg and this is purely due to the ambient outside temperature affecting the skin temperature. The problem that very few people realise is that the alarm threshold or ‘Fever Temperature’ on the device used, needs to be dropped in accordance with the average skin temperature, for instance in the mornings when temperatures are attained at between 32.5 and 33.9 an average needs to be established which in the above case is 33.2 deg, add a differential of 1.5deg C and your fever threshold is now 34.7 and not 38 degrees Celsius.
The problem with taking temperatures more so in the morning, is that should a child or teacher have a fever or mild fever, due to the setting of the fever threshold at 38 deg, these teachers or children would still gain entry to schools as the ambient temperature has decreased their skin temperatures below the “alarm threshold” of 38 deg.
HOW DO WE PREVENT INCORRECT READINGS WHILST SCREENING?
Organisations need to be proactive in setting up a ‘constant’ ambient environment prior to each screening session (as three have been dictated during the course of a school day) and understanding that they are taking skin temperature and not body temperatures and the anomalies that can occur.
When screening it is important to keep the environment temperature stable and the individual screened has to be given 5 – 10 minutes within the confines of the screening environment for their skin temperature to adjust accordingly and a second test completed.
In the adverse affect, where the skin temperature does not drop after allowing that person to remain within the confines of the ambient temperature and remain at 36.5 deg we decern that that person could well now have an EST (Elevated Skin Temperature) and now requires a medical thermometer to again check that they in fact do or don’t have a relevant fever or EBT (Elevated Body Temperature) On checking with a medical thermometer by medical personal then again that person will either be allowed or not allowed to proceed dependent on the medical practitioner completing the reading of the temperature and the screening process.
Remember that having a fever or EST or EBT does not necessarily mean that you have Covid 19 or the Corona Virus – only further testing will and can determine that,
Also, bear in mind that there are other factors that can also influence body temperature and skin temperature apart from the environment – some of these include – sweat, exertion, ethnicity, gender, menstruation, underlying illnesses etc. – multiple readings over a day will help set a mean.