Zika fever: the price of success

Evgeny Zolotov, Computerra 

The dominant species sooner or later begins to suffer because of its excessive numbers. The misfortunes, of course, are always different, but the reason is common: monoculture, that is, a lot of the same type, identical "in structure" individuals. In such an environment, diseases easily multiply – regulating the size of the population and eventually returning it to normal, preventing long-term distortions in the biosphere. 

Man has probably become the first living being who consciously tries to withdraw himself from the action of this law. After all, nature itself has endowed us with reason, so why not try? But evolution does not give up, throwing up new threats: plague, cholera, syphilis, Spanish flu, AIDS… And a question that you often want to hear the answer to: how are we coping, what's the score? Are we losing the fight or are we still holding the punch? The outbreak of the Zika virus pandemic in the southern hemisphere allows us to look at this confrontation from a new angle.

Zika has been known to scientists since the middle of the XX century, when it was isolated from monkeys, and then humans, in Africa (actually the name is given by the name of the forest in Uganda). It is a relative of yellow fever, West Nile fever and some other similar ones – both in terms of symptoms and in terms of the mechanism of transmission. It is known that the virus can be transmitted through close communication, sexual contact, but mostly it travels on the Aedes aegypti mosquito (aka the yellow–horned snapper) - a very popular type of mosquito living in the tropics. A mosquito bites a sick person, then a healthy person and thus introduces the virus. And that, after a short incubation period, causes a fever of the same name. 

Here it should be noted that, firstly, the symptoms of the disease do not manifest themselves in everyone, but only in two people out of ten. That is, the sick person does not always even know that he is sick. Secondly, even in people with severe symptoms, Zika fever occurs most often easily: fever, headaches, aches, sometimes a rash. Not harder than a banal cold. And that's also why there are no medicines created: there is no vaccine, or even any specific drugs to fight the virus. In the worst case, they bring down the temperature, but in general, it's enough for the patient to just lie down.

The problem is that in the third millennium, Zika, together with its carrier, went on the attack. The reason is tourism and globalization in general (trade, business contacts, etc.), plus, as some believe today, global warming. The yellow-horned snapper, which breeds only in very warm climates, has now spread to dozens of countries (mainly in the Southern Hemisphere), capturing areas in Africa, South America, even in the Asia-Pacific region. The virus moved with him. And since 2007, its first pandemic has been counting down: Zika has become an international disaster. However, even this would have been ignored if not for the terrible feature he acquired at the same time: he probably mutated and now, presumably, causes severe deformities in patients.

Registered cases of microcephaly in Brazil. Official data.

It was discovered by chance, in Brazil, where the aforementioned mosquito bothers the population especially much. Suddenly, without an obvious reason, there was a surge of microcephaly in the country (a child is born with a skull and a brain smaller than normal, mental insufficiency; it does not respond to treatment). In 2015, about 4,000 cases were recorded (according to data published on the night of January 28-28, more than four have already been recorded; the rate is growing weekly) – compare this with the average annual 150 people.

Trying to determine the cause, Brazilian doctors found that in many cases there is a connection with the Zika virus. Either the mothers suffered a fever during pregnancy (and here the data is probably incomplete: rapid diagnostic tools so far detect the virus only at the acute stage of the disease, which lasts less than a week), or the virus was isolated in the blood of a newborn, or a surge of microcephaly occurred in the same areas where a surge of Zika fever was recorded, etc. Similar facts have been revealed in neighboring countries, however, in smaller quantities.

Victim of microcephaly.

A preliminary conclusion about the probable connection between the virus and the deformities was made by officials in Brazil a few weeks ago – and since then the situation has only gotten worse. The region in which a third of the world's population lives was under attack. The media are doing their best not to inflate panic moods, in particular, painfully avoiding such words as epidemic and pandemic. WHO officials are also trying to smooth out the impression of what is happening – tirelessly repeating that a firm link between the Zika virus and microcephaly has not yet been revealed, but agreeing at the same time that "indirect evidence is extremely serious." Gathers a special UN meeting.

And the countries of the region, one after another, follow the example of the Brazilian Ministry of Health – and offer women to postpone pregnancy at least until 2018, when a vaccine or medicine may appear. In addition, the United States (which is theoretically threatened by Zika only in the warmest corners), the EU and some other states have issued recommendations for tourists (especially pregnant women and people planning pregnancy) to avoid trips to more than two dozen countries in Latin America, the Caribbean, the Pacific Ocean and West Africa; major airlines and tour operators they have already promised to cancel such tickets and tours without fines. But even we are under attack, since the Dominican Republic (officially included in the list of dangerous places) and Thailand are among the favorite resorts of Russians. Think three times before buying (especially wedding!) tour to these countries. Those who have suffered from Zika fever are advised to refrain from pregnancy for another two years.

The apocalyptic picture is emphasized by futuristic countermeasures. There is little hope for a vaccine. It can presumably be created, but it will probably take years, and it will be possible to develop immunity only in women who have not reached puberty (I will not vouch for accuracy, but such an idea has been expressed). There are no medications yet either. What can we oppose to the virus right now? Only genetic engineering.

The areas potentially affected by Zika are the same,
as for other diseases carried by the yellow-boredom biter.

It just so happened (that's where the scope for conspiracy theorists is!) that Brazil was the first country in which experiments on the release of genetically modified mosquitoes were conducted en masse, with the support of municipalities. In particular, the GM variant of the yellow-boredom snapper. The British company Oxitec designed such a mosquito: it turned on a gene that makes the offspring unviable, and released tens of millions of males in some parts of the country. It did not lead to the complete destruction of mosquitoes there, but it reduced the population by nine tenths. Which is considered a very good result, because the remaining ten can be fought with classic means: mosquito nets, traps, repellents, spraying, etc.

Unfortunately, the situation is developing so rapidly, and the likely consequences are so severe that the most likely prospect for the near future remains the following: genetic engineering will protect prosperous countries, but Zika will recoup in full force on their poor neighbors, causing millions of deaths and crippled destinies. To call such a prospect a "victory over the disease" does not turn the tongue. However, returning to the question with which today's story began, it is appropriate to ask whether this can be considered a defeat.

Yes, the official (!) forecasts of cases for the next year are hundreds of thousands in Brazil alone. And we cannot guarantee the survival of each individual. But the survival of the species is already within the power of man to guarantee. And here we certainly benefit from nature: even such a terrible attack as the Zika virus is no longer able to destroy Homo sapiens.

Portal "Eternal youth" http://vechnayamolodost.ru

29.01.2015