Dr. Tim's Spineless Wonders

Sit, Stay and Don’t Shake Paws

Monday, May 4th, 2020

A lot has happened since my last column. Our sense of normality has been drastically altered. We are staying home more, and when we do go out for necessities we are very cautious of everyone else’s movements so that we don’t violate the 6-feet safe space. We habitually wash hands, disinfect surfaces and even wear face masks, all in an effort to slow the spread of the virus that causes COVID-19.

It is safe to say that everyone has learned much more about viruses in general, and this one in particular, than they would ever have anticipated a month ago. But even so, there is a lot that remains unknown. Even medical experts on viral diseases and disease transmission admit that this pandemic has many unique characteristics that are new. We are all learning as we go.

In last month’s column I discussed the similarities and differences between RNA coronaviruses and other influenza viruses. Coronaviruses, including SARS, from 2002; MERS, from 2012; and now COVID in 2019, are potentially more serious because they are extremely contagious and quickly attack, inhibit and compromise human respiratory functions.

Only three coronaviruses are zoonotic (jump from non-human animals to people). The term zoonosis stems from the Greek “zoo,” which means animal, and “nosis,” which means sickness. Bats seem to be common reservoirs for coronaviruses and are speculated to be the origin of COVID-19.

These may spread directly from an infected animal to a person through a bite or even a scratch, such as in the case of rabies. We also recognize that insects, especially those that suck blood, play a huge role in the transmission of zoonotic infectious diseases: Lyme disease by ticks, the plague by fleas, malaria and a multitude of influenza diseases by mosquitos.

By comparison, these diseases are not contagious from person to person like COVID-19. And thankfully so. But what if they were? And what if the reverse was true, that COVID-19 could be spread by mosquitos and ticks? Answers to these questions are what inquiring minds are now seeking as we navigate all possible COVID-19 transmission ramifications. Recent questions sent to me seem to center on the role of mosquitoes or ticks in vectoring COVID-19 and also the role of other animals possibly harboring or even transmitting the disease.

In last month’s column I stated that, although biting insects do transmit many deadly diseases we should all be mindful of, they are NOT known to transmit coronaviruses and thus are very unlikely to play a role in the spread of COVID-19.

Since that time, experts from the Centers for Disease Control (CDC) Division of Vector-Borne Diseases, Entomological Society of America (ESA) and the World Health Organization (WHO) all reaffirm that there is no evidence to suggest that the coronavirus SARS-CoV-2 or other similar coronaviruses are spread by mosquitoes or ticks. So, to dispel any rumors or myths to the contrary, I again echo their findings: The corona virus is NOT transmitted by blood-feeding arthropods.

Rather, contagious diseases (flu, colds, or COVID-19) are spread person-to-person via direct physical contact, such as with another person who has the infection or touching something they have contaminated and then moving the virus to a face. Even more commonly, airborne viral microbes can be inhaled as they travel through the air as a result of someone nearby sneezing or coughing. These types of transmission require close proximity and are what “social distancing” is designed to curb.

Dog wearing a face mask.

Leonard. Photo by Tom Campbell

But how to answer the question regarding other animals: “Can the virus be spread by a cockroach or a rat rummaging through garbage down the block, or a house fly that moves from a quarantined neighbor’s house to ours?”

In an absolute, certain, scientific context, I would have to say, “Yes, it is possible that these animals may pick up viruses from contaminated surfaces on their feet or fur and then transmit them to where people may unwittingly contact them. We call this mechanical transmission, and it is a major problem posed by such filth pests.” However, in the case of COVID-19, the threat posed by this mode of transmission pales in comparison to the more contagious method described above. Further, if we practice the sanitation and cleaning techniques recommended for COVID-19, we will largely be protected from both.

A follow-up question, raised by my more astute and deep-thinking readers, deals with yet other animals. “If this is, as you say, a zoonotic disease that originated from bats in Wuhan, China, how can we be sure that other animals cannot become infected, harbor and then transfer the virus to people?” And a related and even more specific question: “Since the discovery of the virus in bats there have been news reports of other mammals being infected. For example, some tigers at a zoo in New York City tested positive for corona after being exposed by an infected worker. Pet dogs and cats living with quarantined people have also tested positive for COVID-19. Shouldn’t we be concerned about pets passing the virus?”

Let me first say that such cases are comparatively very, very few. Though testing positive, these animals mostly manifested only mild respiratory symptoms and have since recovered. But the question remains: “If people can pass the virus on to animals, can animals pass the virus to people?”

The fact that pets have come down with the virus (ostensibly transmitted by their owners) begs the question: “If companion animals can contract the virus from people, can people also get the virus from their pets?”

As with other details about this virus and how it is transmitted, there are a lot of things we still do not know, but there is no evidence to suggest the virus that causes COVID-19 is harbored in other mammals, domestic or wild, or that these play a significant role in spreading COVID-19.

That said, this virus (as with all viruses) has a remarkable propensity to change, mutate and shift in very short periods of time. Together with the fact that it is extremely contagious, it would be prudent to exercise common-sense, behavioral changes when it comes to companion animals.

It is a new world, and some human/pet behaviors should be closely scrutinized. I question whether our current understanding supports a need to radically modify how we interact with pets – regularly disinfect the cat, wash the fish’s hands, take the temperature of the parrot, quarantine the hamster, mask the dog or other over-the-top changes. But if you decide to sanitize your cat, please send us video. We may not use it for scientific purposes but it is certain to be entertaining.

Until we learn more about how this virus affects animals, I suggest that we all protect pets as we would other human family members. Here is my newly revised refrigerator door list for both.

Dog wearing bandana face mask.

Zoey. Photo by Paula Hamilton

COVID-19 CONTAINMENT RULES FOR SPOUSES, CHILDREN AND PETS

  • Teach, practice and enforce the commands “sit” and “stay.”
  • Limit kissing, petting and licking to “only when absolutely essential.”
  • No jumping upon or other physical interactions with non-family members.
  • Shaking paws with strangers is an old tradition that may need to be temporarily or permanently removed from our list of socially acceptable behaviors.
  • Keep healthy through proper exercise and diet regimes. These are independent. Ravenous eating does not count as exercise.
  • Regularly sanitize hard surfaces, food bowls and litter boxes.
  • Watch for disease symptoms. If they occur, further isolate/quarantine. This may seem inordinately harsh but is absolutely necessary. Personal note: Cats usually do not mind quarantines because most are introverts anyway.
  • Do not pet or touch non-family members even if they approach you. This includes tigers.
  • Avoid parks or public places where large numbers of people or pets gather and cannot contain their excitement.
  • Use a leash or other means to maintain at least 6 feet of space from others. (Shock collars are available for larger/slower learners, of which every family has one or two.)
  • Wash hands and paws regularly.
  • Keep current on all doctor-recommended vaccinations. Remember, vaccines should not be shared BETWEEN species.

Meanwhile, amid our focus on COVID-19, don’t forget to protect yourselves and your pets from annual mosquito and tick-borne diseases. Preventing bites remains the best method for preventing disease transmission. Know when and where mosquitos and ticks are most dangerous, and avoid those places and times. Simple common-sense, behavioral changes learned over the years have made a big impact on preventing insect-borne diseases. Wearing insect repellents, showering and conducting tick checks after hiking in the woods, recognizing symptoms, and keeping up with vaccinations are all things that have reduced our exposure to diseases.

Oh, and wash your hands.

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