Years back while in veterinary school, our public health professor of zoonosis warned us that failure to recognise diseases in wild and domestic animals that can be transmitted to humans is the greatest sin a vet can commit.
The diseases are called zoonoses. He further told us that such diseases do not necessarily have to be initially infective to humans but human exposure can make disease-causing organisms, called pathogens, change their genetic code or adapt to infect the human host.
I recalled these words as if he was talking yesterday as I analysed the current coronavirus outbreak, whose epicentre is China.
Since the outbreak in December 2019, the virus has run wild and spread rapidly to all corners of the globe. The World Health Organization (WHO) has since declared the disease a global pandemic and instituted measures to contain further spread, prevent new cases and eventually control it.
Zoonoses include infections such as rabies, tuberculosis, brucellosis and ebola. Most of these diseases are caused by viruses and bacteria.
The current coronavirus outbreak is suspected to have emanated from bats and snakes sold as food in a wet meat market in Wuhan, China.
Scientists determined that the human body had not been exposed to the virus before and named it Covid-19 (coronavirus disease 2019). Such viruses are called novel, meaning they are new to medical science.
The coronavirus family is well-known to medical scientists in both human and animal health, but Covid-19 is a new strain to both scientists and the human body.
The corona family causes many diseases in children and young animals, adult humans and animals. These include diarrhoea in children and young animals, common cold in humans and gut infection and pneumonia in adult pigs.
Apart from Covid-19, other coronavirus strains have jumped species from animals and infected humans causing severe disease and mortality in the recent past.
They include the Severe Acute Respiratory Syndrome (SARS) outbreak of 2002 that emanated from a Chinese wet meat market and was traced to wild civet cats.
There was also the Middle East Respiratory Syndrome (MERS) outbreak of 2012. The virus was traced back to camels in Saudi Arabia.
Though these previous outbreaks spread from the epicentre to many other countries, they were put under control before becoming major pandemics, mainly because they were not very easily passed on from one person to the other.
The major challenges with Covid-19 are its ease of person-to-person transmission and its long incubation period of up to two weeks. During this period, the infected person does not show signs of the disease.
It, therefore, means infected people can travel long distances and to many places before they are diagnosed with the infection. This is one of the reasons there is rapid spread of the disease considering today’s global interconnectivity.
I am motivated to write about Covid-19 because of the many questions I have received from readers, especially via WhatsApp.
Most of the enquiries have revolved around treatment and preventive products and our preparedness for the disease in Kenya. Other people have wondered whether we really have the capacity to diagnose the disease.
First, I must say that Covid-19, as it is now, is a human pandemic because transmission is between people. However, we also can reasonably speculate that susceptible animals could get infected from humans since the disease initially came from animals.
Therefore, as human medical scientists deal with the disease in people, veterinary scientists must also keep checking that vulnerable animals are not infected as well to prevent spreading of the disease to new animal populations.
We must keep checking whether animals close to humans such as pets and livestock can be infected by the virus; become mechanical carriers or carriers without symptoms. This just goes to show the multiple challenges that a new infectious pathogen places on medical scientists.
FOLLOW THE GUIDELINES
At a social function last Saturday in Murang’a, a farmer asked me whether Covid-19 can affect cattle, sheep and chickens if an outbreak occurred in a family.
You see, most farmers live close to their animals due to space and security constraints. Currently, the virus is not known to affect livestock.
Scientists are still studying the pathogen to understand it better. However, it is advisable for infected people to distance themselves from animals until the extent of the virus host range and activity is understood.
Meanwhile, I advise that you trust the government when it says it has sufficient capacity to test for Covid-19 because when it did not, it clearly stated the samples were being taken to South Africa for testing.
Second, using the phone system to disseminate public health messages as the government is doing is quite effective as one gets verifiable authoritative information.
There is also screening of all people at entry points and international conferences have been cancelled, measures that seek to keep the disease out of our borders.
My advice to those enquiring about cure and prevention products is that they undergo rigorous medical testing and are licensed by respective authorities in the country of origin.
Further, similar products for Covid-19 would have WHO endorsement. In the meantime, there is no known cure for the disease as is the case with most viral infections.
The best way to address Covid-19 issues is to seek information from health authorities, the global health authority WHO and reputable medical institutions such as the American Centres for Disease Control (CDC) and the Kenya Medical Research Institute (Kemri).
Kindly closely follow the guidelines given by the health authorities at the individual and community level.