I recently devoted a post to mocking the media storm around hantavirus. As I assured y'all, it is fading away without further consequence. That does not mean, however, that we should not continue to have major concern about the possibility of a truly horrific global pandemic. In fact, the probability continually increases as the human population continues to grow, become more concentrated in dense cities, become more highly mobile, and press into formerly remote areas. All of this is compounded by climate change, because warmer climates are more conducive to infectious disease (the tropics have always been the most disease-ridden parts of the planet) and the range of important disease vectors expands northward.
So is Ebola virus the next big thing? No, not really. The current outbreak in west Africa is really bad news for the affected communities, but Ebola is readily containable wherever there are adequate medical and public health resources. The reason is that it can only be transmitted by direct contact with bodily fluids, and only while the person is symptomatic. (There is an exception I'll get to, but it isn't a major concern.) To be sure, people who are symptomatic produce a lot of bodily fluids. Ebola is classified as a hemorrhagic fever, because it makes people bleed from their various orifices. So medical personnel trying to help victims need to be fully protected from contact.
However, it is not spread through the air, unlike say, measles or Covid 19. The really bad news about Covid is that asymptomatic people can be infectious, which means there are people walking around who don't know they are infected who are transmitting it to other. HIV also can only be transmitted by direct contact with bodily fluids, and even then not easily, usually only by sexual intercourse or sharing needles. But the problem is that people can be asymptomatic for years, and so have plenty of time to infect other people, and even if they do become symptomatic they don't necessarily know that what they have is HIV unless they are in contact with medical doctors, and even then they might be irresponsible. That can't happen with Ebola. (Believe me, a person with symptomatic Ebola disease is not going to have sex.)
Now, to get to the exception. It does appear that those relatively few people who recover from acute Ebola infection can transmit the virus sexually for a period after they recover. That doesn't mean months or years, as with HIV, and it also can't create a chain of infection as with HIV because if someone does become infected, they'll become acutely ill and probably dead before they have a chance to infect someone else. The point of all this being:
To produce a severe, widespread infectious disease epidemic or pandemic, a pathogen needs either to be:
1) Readily transmissible through the air, especially by people who are asymptomatic or have only mild symptoms that don't leave them knocked out on the sofa or in bed; or
2) Transmissible by animal vectors such as mosquitoes or fleas that bite infected people whether or not they are symptomatic and whether or not they are up and about, and pass it on to others.
The latter condition applied to the Back Death, but since we understand that now and can more effectively control rats and fleas, it's not a big concern. It also applies to malaria which continues at endemic levels in parts of the world where the vector mosquitoes can live, an area that is expanding with climate change. I don't want to downplay malaria, it's a drag, and it has evolved multi-drug resistance which makes it even harder to deal with. On the other hand, there is a somewhat effective vaccine now, we do have ways of protecting people from mosquitoes, and effective biological controls are on the horizon. So that's not a huge worry, although we need to continue to invest resources in malaria control.
Influenza is in category 1, and it's a complicated story. It is continually evolving in birds and swine, and so new strains emerge each year to which segments of the population may have more or less immunity depending on whether they have been infected with, or vaccinated against, closely related strains in the past. Vaccine manufacturers are constantly racing against viral evolution and trying to match this year's shot with what they expect will be going around, with varying success from year to year. Flu strains also vary greatly in virulence, i.e. how sick they make people. Scientists are working on a universal flu vaccine, using methods that the Dump administration refuses to fund, but hopefully the Europeans will come through for us. So we might have a bad flu season but 1918 almost certainly won't happen again.
So, Ebola virus is a big deal where it's happening now but little to no deal where it isn't, certainly nothing to be majorly worried about in the U.S. of A. Recently coronaviruses have proven to be a major concern. Like influenza, they are constantly evolving in various animals -- bats are the best known reservoir but they aren't the only one. And what we get aren't just novel strains of a virus to which we at least have some immunity, like flu, but whole new categories of virus to which human immune systems are naive. The virulence of Covid-19 happened to increase quite sharply with age, but the next one might be just as dangerous to children and young adults, or even more so, as was the case with the 1918 influenza.*
So, it is very important that we get rid of the lunatic in charge of HHS, and all of the fellow lunatics he has appointed to key positions in public health and biomedical research.
*The 1918 flu tended to kill people by overactivation of the immune system, resulting in a so-called cytokine storm, runaway inflammation that caused multiple organ failure. Older people whose immune systems were less active were less vulnerable.
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