PANDEMIC VS EPIDEMIC

Pandemic vs Epidemic

By JJ KARWACKI 18 March 2020

Strictly defined

COVID-19 may indeed be pandemic in that it has spread to most every place in the world. But in most of those places it is not yet epidemic. I use those terms in the strictest sense of their meaning.

Except in a few well defined places (Wuhan, Italy, South Korea & Iran) this disease is occurring in clusters. At the center of each of those clusters is a traveler, mainly from one of those countries named above. Other notable clusters have occurred on cruise ships. Most people infected to date have either traveled from one of those heavily infected areas or have been in close contact with such a traveler. IOW, this virus is not out and about infecting random people in random places. Hence, my contention that it is not strictly an ‘epidemic’. Just about every case has a known source. Contacts of that source can be isolated (quarantined) and placed under care if ill. As long as the contacts are contained, so will the spread of the virus.

The real danger of an uncontrolled spread amongst the general population is if the known cases break containment. The greatest threat is from those who do not know they are sick or refuse to accept responsibility to stay away from others. It does seem as if it is possible for infected but not ill people to spread this virus. One cluster like this is seemingly a threat here in Thailand. A fair number of people (2 dozen?) who attended boxing matches then carried that virus home with them. They dispersed fairly widely and exposed others before they, themselves, showed symptoms. The source of the stadium exposure is as yet unclear, but given the recent history was probably the close contact of a traveler. This cluster does, however, show the potential for spread by more casual contact. These people shared nothing in common except space and air.

Another cluster is more indicative of what seems to be happening worldwide. A group of 20 or so friends gathered for a party. One of them had had recent contact with a traveler. He shared glasses of whiskey with 10 of his friends. All of them are now ill. No cases have been confirmed in the other 10 who did not share saliva.

I use these as an indication that it takes reasonably close contact with an infected person to contract this disease. Currently, it is not lying about in ambush for unsuspecting random people to infect. Within the USA, it seems that only CA, WA and NY have actual epidemic spread. Across the vast US mainland, the other cases are occurring in small clusters. But they add up fast. I’m guessing that the vast number of the known US cases have an identifiable source, likely travel-related.

These small clusters suggest that large open places like malls are of little threat. Small entertainment venues where people are in close contact or where they are more static and in close quarters (movie theaters or concerts) pose a credible threat of exposure, but only if there is that one infected person there to shed and spread the virus. In any given locality, such people are few and far between

One problem with counting known cases is that that count is always behind the actual number of infected people. There is always someone who is infected but without symptoms (in the incubation period). But unlike the classic case of measles where not-yet-ill shedders are highly infectious, COVID carriers are seemingly most infectious when they are at the height of their symptoms. So they are the greatest threat to those family, friends or medical personnel attending to them.

I’m certainly not advocating being complacent. I’m NOT saying ignore the threat. It is real and could change at any time. The key to controlling this infection is to contain the virus so that each case is spread to a minimum of people. Even if each case only infects 2 others, the numbers rise quickly. But with measles, that number is closer to 10 than 2! Quarantine of any and all known cases (hospitalization is a form of quarantine) is imperative. Self-quarantine by everyone with a respiratory illness is mandatory until that illness can play out as with a common cold or seasonal flu. Should that illness worsen to trouble breathing then medical attention is needed.

Much has been said about the lack of tests for COVID in the USA. Wide-spread random testing of non-ill people is a waste of scarce resources. This is known as ‘screening’ and has inherent problems of its own. COVID tests need only be run to distinguish it from the background of other more common, less serious respiratory diseases in circulation simultaneously. Early identification and hospitalization can save lives, even though they is no direct treatment. But there is also the real threat (as has occurred in Italy) where the entire medical system can become overloaded by those seeking care or diagnosis of COVID. Hence, the opening of “drive-in” test centers all across the country.