Nature isn’t benign. Homo sapiens has been vulnerable to microbial assaults over the last millennia. Viruses are learning new tricks, and we are caught in the food chain whether we like it or not, eating and being eaten. Disease-carrying organisms are being forced into areas of human habitation as the population increases, raising the real possibility that lethal microbes would infect humanity on a large scale. Viruses are evolving far more rapidly than Homo sapiens, and our immune systems are being overwhelmed.

The COVID-19 is a coronavirus believed to originate from bats. How do we know? It has a genome similar to a strain in bats. The virus crossed into a mammalian host, thought to be a pangolin, and eventually humans by a series of mutations.

The COVID-19 is more dangerous than the seasonal flu. It has a higher degree of spreadability, meaning that an infected person with this virus, is capable of infecting 2.3 to three people by sneezing or coughing. Each of these three people can infect three more. Thus, three people can infect a total of nine individuals who can themselves infect 27, and so on — an exponential increase. The spreadability of the flu is only about 1.3 persons infecting another person — not exponential.

Being a new (novel) virus, humans have not acquired antibodies and will have very little resistance to this virus. The effects will be more severe, the elderly with weaker immunity being more vulnerable. Some 97 per cent who get the virus will develop symptoms within 11 days, usually within five days. This gives people more time to spread the virus while asymptomatic, before becoming sick. The flu takes only about two days.

Make no mistake, we are at war. On the front line are doctors, nurses, and other health workers risking their lives in hospitals, and their colleagues in health centres and private practices providing essential backup services. Here are some guidelines for the public:

If you have a persistent cough, usually unproductive, fever (not in all cases of the virus), shortness of breath, recently travelled, come in contact with someone who has travelled, in contact with a COVID-19 patient, or live in an area with a known case of the virus, you should call or visit your doctor.

Do not go to the hospital for not only will you add more congestion to an already congested hospital, but if you have the virus you may infect others, or end up being infected by other patients.

By carefully listening to your symptoms your doctor may suggest that your cough may be due to other causes (allergy, drugs, etc), and your temperature should be checked by a thermometer if possible. A feeling that you have fever can be deceptive.

You may be advised to quarantine yourself for 14 days. If symptoms worsen — an increase in temperature, shortness of breath — you will be asked to contact the COVID-19 Health Team. The team will do a test, and if positive for the virus, you will be admitted to an isolation centre in a hospital. If, however, while quarantined you have mild symptoms, or are asymptomatic, providing all tests are negative (an antibody test should be mandatory to determine if you have been exposed to the virus and are now immune), you may be allowed to resume normal activity. Of course, your doctor will see you for other medical conditions not related to the virus, and if necessary do house calls (not all doctors do house calls) if you are unable to go to his office.

What can you do to help yourself? Firstly, you should be in a state of preparedness, not in a state of panic. Wash hands with soap; use sanitisers; and wear masks, especially in areas where the virus is prevalent. Recent experiments show that a cough or sneeze can be transmitted three metres, not one metre as previously thought. And, as asymptomatic people can carry the virus, it may be more prudent to wear masks more often than previously advised, preferably N95 masks, with proper hygienic handling and changing them frequently. Health care workers tending to the sick should wear masks and other protective equipment, and anyone who has respiratory symptoms should wear a mask.

It has been shown that proper control of the spread of the virus, depends on avoiding large crowds, social distancing; oops, I am sure we mean physical distancing not social distancing. After all, as caring humans we do need to keep socially connected, especially in these troubled times. And, self-quarantine.

Religious meetings in churches and funerals are notorious for spreading the virus. “Religion is unfairly targeted,” say the religious fringe. But isn’t God omnipresent and not limited to church buildings. Prayers and holy water don’t seem to help.

Jamaicans have always been a relatively healthy people, thanks to the country’s universal and robust immunisation programme. BCG (Bacillus Calmette–Guérin vaccine), one of the vaccines given to newborn babies to protect against tuberculosis, also boosts the immune system against a wide range of viruses and bacteria. It has been shown that countries with inadequate BCG programmes — USA, Italy, Germany, Spain, France, and Iran — have higher death rates than countries like Japan and South Korea, which have mandatory and universal BCG vaccine policies. While we desperately wait for a COVID-19 immunisation, will our BCG immunisation status confer some amelioration of the severity of this virus?

In the meantime, widespread testing — though some test kits are reported to be unreliable — of both symptomatic and asymptomatic people is crucial.

Ethon Lowe is a medical doctor. Send comments to the Jamaica Observer or ethonlowe@gmail.com.