In 2008, something incredible happened: a man was cured of HIV. In over 70 million HIV cases, that was a first and, so far, a last. We don't yet understand exactly how he was cured. We can cure people of various diseases, such as malaria and hepatitis C, so why can't we cure HIV? Well, first let's examine how HIV infects people and progresses into AIDS.
U 2008. godini se desilo nešto neverovatno: čovek je izlečen od HIVa. U preko 70 miliona slučajeva HIVa, ovo se desilo prvi, i, do sad, zadnji put. I dalje ne razumemo kako je on tačno izlečen. Možemo da izlečimo ljude od različitih bolesti poput malarije i hepatitisa C, pa zašto onda ne možemo da izlečimo HIV? Pa, hajde prvo da ispitamo kako se ljudi zaraze HIVom i kako on napreduje u AIDS.
HIV spreads through exchanges of bodily fluids. Unprotected sex and contaminated needles are the leading cause of transmission. It, fortunately, cannot spread through air, water, or casual contact. Individuals of any age, sexual orientation, gender and race can contract HIV.
HIV se širi preko razmene telesnih tečnosti. Nezaštićen seks i zaražene igle su glavni uzročnici prenošenja. Na sreću, ne može da se širi putem vazduha, vode, ili slučajnim dodirom. Pojedinci svih starosti, seksualne orijentacije, pola ili rase se mogu zaraziti HIVom.
Once inside the body, HIV infects cells that are part of the immune system. It particularly targets helper T cells, which help defend the body against bacterial and fungal infections. HIV is a retrovirus, which means it can write its genetic code into the genome of infected cells, co-opting them into making more copies of itself.
Kada uđe u telo, HIV inficira ćelije koje su deo imunog sistema. Posebne mete su mu T pomoćne ćelije, koje pomažu telu da se brani od bakterijskih i gljivičnih infekcija. HIV je retrovirus, što znači da može da upiše svoj genetički kod u genom zaraženih ćelija, navodeći ih da prave svoje kopije.
During the first stage of HIV infection, the virus replicates within helper T cells, destroying many of them in the process. During this stage, patients often experience flu-like symptoms, but are typically not yet in mortal danger. However, for a period ranging from a few months to several years, during which time the patient may look and feel completely healthy, the virus continues to replicate and destroy T cells. When T cell counts drop too low, patients are in serious danger of contracting deadly infections that healthy immune systems can normally handle. This stage of HIV infection is known as AIDS.
Tokom prvih faza infekcije HIVom, virus se množi unutar T pomoćnih ćelija, uništavajući ih tokom tog procesa. Tokom ove faze, pacijenti često osećaju simptome slične prehladi, ali obično još nisu u smrtnoj opasnosti. Međutim, tokom perioda od nekoliko meseci do nekoliko godina, pacijent može izgledati i može se osećati potpuno zdravo, dok se za to vreme virus množi i uništava T ćelije. Kada se broj T ćelija drastično smanji, pacijenti se nađu u ozbiljnoj opasnosti da se zaraze smrtnim infekcijama s kojima se zdrav imuni sistem inače može izboriti. Ova faza zaraze HIVom je poznata kao AIDS.
The good news is there are drugs that are highly effective at managing levels of HIV and preventing T cell counts from getting low enough for the disease to progress to AIDS. With antiretroviral therapy, most HIV-positive people can expect to live long and healthy lives, and are much less likely to infect others.
Dobra vest je da postoje lekovi koji su veoma efikasni u kontrolisanju nivoa HIVa i u sprečavanju da se broj T ćelija toliko smanji da bolest uznapreduje u AIDS. Sa antiretrovirusnom terapijom, mnogi HIV pozitivni ljudi se mogu nadati dugim i zdravim životima, i mala je verovatnoća da će zaraziti druge.
However, there are two major catches. One is that HIV-positive patients must keep taking their drugs for the rest of their lives. Without them, the virus can make a deadly comeback.
Međutim, postoje dve velike zamke. Jedna je da HIV pozitivni pacijenti moraju nastaviti da uzimaju lekove do kraja života. Bez njih, virus može da se vrati sa smrtnim posledicama.
So, how do these drugs work? The most commonly prescribed ones prevent the viral genome from being copied and incorporated into a host cell's DNA. Other drugs prevent the virus from maturing or assembling, causing HIV to be unable to infect new cells in the body.
Dakle, kako ovi lekovi deluju? Lekovi koji se obično propisuju sprečavaju kopiranje virusnog genoma i njegovo pripajanje u DNK domaćinove ćelije. Drugi lekovi sprečavaju da virus sazre ili se obrazuje, onesposobljavajući HIV da inficira nove ćelije u telu.
But HIV hides out somewhere our current drugs cannot reach it: inside the DNA of healthy T cells. Most T cells die shortly after being infected with HIV. But in a tiny percentage, the instructions for building more HIV viruses lies dormant, sometimes for years. So even if we could wipe out every HIV virus from an infected person's body, one of those T cells could activate and start spreading the virus again.
Ali HIV se krije negde gde naši današnji lekovi ne mogu da dosegnu: unutar DNK zdravih T ćelija. Većina T ćelija umire ubrzo nakon što bude zaražena HIVom. Ali u jako malom procentu, uputstva za razvoj još više virusa HIVa su skrivena, ponekad godinama. Tako da kad bi i mogli uništiti sve i jedan virus HIVa u telu zaražene osobe, jedna od onih T ćelija bi se mogla aktivirati i početi da ponovo širi virus.
The other major catch is that not everyone in the world has access to the therapies that could save their lives. In Sub-Saharan Africa, which accounts for over 70% of HIV patients worldwide, antiretrovirals reached only about one in three HIV-positive patients in 2012. There is no easy answer to this problem. A mix of political, economic and cultural barriers makes effective prevention and treatment difficult. And even in the U.S., HIV still claims more than 10,000 lives per year.
Druga velika zamka je da nemaju svi ljudi na svetu pristup terapijama koje bi im mogle spasiti živote. U Podsaharskoj Africi, koja ima preko 70% HIV pacijenata u odnosu na celi svet, antiretroviruse terapije su bile dostupne samo jednom od tri HIV pozitivna pacijenta u 2012. godini. Ne postoji jednostavan odgovor na ovaj problem. Mešavina političkih, ekonomskih i kulturnih prepreka otežava efikasno sprečavanje i lečenje. Čak i u Sjedinjenim državama, HIV i dalje odnosi preko 10 000 života godišnje.
However, there is ample cause for hope. Researchers may be closer than ever to developing a true cure. One research approach involves using a drug to activate all cells harboring the HIV genetic information. This would both destroy those cells and flush the virus out into the open, where our current drugs are effective. Another is looking to use genetic tools to cut the HIV DNA out of cells genomes altogether.
Međutim, postoji veliki razlog za nadu. Istraživači su možda jako blizu pronalaženja istinskog leka. Jedan pristup istraživanju podrazumeva korišćenje leka koji aktivira sve ćelije koje nose genetsku informaciju HIVa. To bi i uništilo te ćelije i isteralo virus napolje, gde su naši sadašnji lekovi efikasni. Drugi pristup koristi genetički alat kojim se potpuno iseče DNK HIVa iz genoma ćelije.
And while one cure out of 70 million cases may seem like terrible odds, one is immeasurably better than zero. We now know that a cure is possible, and that may give us what we need to beat HIV for good.
Iako možda jedan lek u 70 miliona slučajeva predstavlja užasne izglede, jedan je nemerljivo bolji od nule. Sada znamo da je moguće doći do leka, i to nam može ponuditi ono što nam treba da jednom zauvek pobedimo HIV.