Skip to main content

Russian doll disease is a virus inside a parasite inside a fly

Russian doll disease is a virus inside a parasite inside a fly

Russian doll disease is a virus inside a parasite inside a fly
Red blood cell, complete with Leishmania parasite (Image: Eye of Science/SPL)
It’s a Russian doll of a tropical disease. Leishmaniasis, a disease that infects 12 million people worldwide, is passed to humans by sandflies infected with the Leishmania parasite.
Now it seems that in some species of the parasite, a virus hiding inside is silently helping it subvert treatment.
Leishmaniasis is a common problem in Latin America, South Asia and parts of Africa. Depending on the form the disease takes and the species of parasite, it either attacks the skin, mucous linings of the nose and mouth, or the internal organs. It’s not easy to treat.
“Treatment failure is a major challenge for doctors and researchers, says Jean-Claude Dujardin from the Institute of Tropical Medicine in Antwerp, Belgium.
Depending on the drug and the region, treatment failure rates vary, says Dujardin. In Latin America, for example, two out of five people relapse after treatment, but this can rise to 70 per cent in parts of South Asia where another species of Leishmania circulates. The most obvious explanation is that the parasite has become resistant or that people aren’t taking the drugs properly.

Infected parasite

But in Latin America at least, it looks like there’s an alternative explanation. A virus that infects the parasite is known to make the disease more severe in mice. It now seems the same applies in people.
“The parasite is already infected by the virus and it is this package that gets transferred to the sandfly,” says Dujardin, part of an international collaboration that hunted down the virus in people infected with the L. braziliensisparasite in the Amazon basin of Bolivia and Peru. Of the people whose parasites were infected with the virus, 53 per cent of them had relapsed after drug treatment. Only 24 per cent of the people whose parasites were virus-free did so.
Similar results were seen in people infected with L. guyanensis, another parasite species common in the area. There was no link between treatment success and the parasite’s resistance to the drugs the patient was given.
“You need to imagine the system like a Russian doll,” says Dujardin. The parasite multiplies within the human host cell, and then the virus lurking within it wakes up and begins interacting with the host cell, he says.
“Leishmania alone, without the virus, is already known to subvert the immune response; it seems that the virus adds another layer of subversion, leading to treatment failure,” says Dujardin.

In good company

In some ways it’s not surprising that a virus can infect a parasite. It’s often said that parasitism is the most common way of life – with more than half of all animal species on the planet living off another in some way.
But Kevin Lafferty, an ecologist at the University of California, Santa Barbara, says that although viruses are known to infect bacteria and parasites, instances of a virus infecting a parasite that in turn infects another host are not very common. “This is a fascinating piece of detective work with important implications for human health.”
However, Jorge Alvar at the Drugs for Neglected Diseases Initiative in Switzerland, cautions that we still don’t how the virus affects the evolution of the parasite, or how it ultimately impacts the patient.
But, in theory, the virus gives us an added drug target, he says. “In this case a patient could be treated with either anti-Leishmania drugs or anti-virals, or both.
Similar viruses have been found in other parasites, for example, in the diarrhoea-causing Giardia andCryptosporidium, and in Trichomonas vaginalis that causes a sexually transmitted infection. Surveys of their prevalence could help us better understand the effect of viral infection of parasites and could play a role in how we treat these parasitic diseases, says Dujardin.
Journal reference: Journal of Infectious Diseases, DOI: 10.1093/infdis/jiv355 (L. braziliensis); DOI:10.1093/infdis/jiv354 (L. guyanensis)

Popular posts from this blog

Hidden Wiki

Welcome to The Hidden WikiNew hidden wiki url 2015 http://zqktlwi4fecvo6ri.onion Add it to bookmarks and spread it!!!
Editor's picks Bored? Pick a random page from the article index and replace one of these slots with it.
The Matrix - Very nice to read. How to Exit the Matrix - Learn how to Protect yourself and your rights, online and off. Verifying PGP signatures - A short and simple how-to guide. In Praise Of Hawala - Anonymous informal value transfer system. Volunteer Here are five different things that you can help us out with.
Plunder other hidden service lists for links and place them here! File the SnapBBSIndex links wherever they go. Set external links to HTTPS where available, good certificate, and same content. Care to start recording onionland's history? Check out Onionland's Museum Perform Dead Services Duties. Introduction PointsAhmia.fi - Clearnet search engine for Tor Hidden Services (allows you to add new sites to its database). DuckDuckGo - A Hidden S…

[SOLVED] IDM WAS REGISTERED WITH A FAKE SERIAL NUMBER

[SOLVED] IDM WAS REGISTERED WITH A FAKE SERIAL NUMBER
Good News [May 08, 2015]: IDM developers got smarter, but the crackers are always a step ahead. Follow this article and send an email to uglyduckblog@gmail.com if you are desperate. I can NOT post any crack here for legal reasons. Happy Downloading with IDM. ;) *********** first tip is to use latest crack for idm from  onhax.net idm universal web crack and make sure u are using all latest vers I am sure many of us are too much dependent on Internet Download Manager a.k.a. IDM. The main reason didn’t permanently switch to linux was IDM. I mainly use it for batch downloading and download streaming videos. Till yesterday, IDM was working fine with me (of course with fake serial numbers, keygen, crack, patch etc. which could be found with little effort). But few days ago, with the latest update version 6.18 build 7 (released on Nov 09, 2013) Internet Download Manager was literally had a breakthrough and crushed all the serial numbers, …

Mouse, touchpad, and keyboard problems in Windows

Mouse, touchpad, and keyboard problems in Windows Introduction This tutorial is designed to help you identify and fix common mouse, touchpad, and keyboard problems in Windows. It doesn't cover device problems related to specific programs. Mouse, touchpad, and keyboard problems can have a number of causes: Cables that aren't connected properly Incorrect device settings Missing updates Corrupted or incompatible drivers Hardware problems Check hardware Many mouse, touchpad, and keyboard problems are caused by hardware that isn't set up properly. Here's some information about how to check your device, make sure cables are connected properly, make sure the hardware has power, and check the settings. Make sure cables are connected properly Check that all cables are plugged in to the correct locations. This can include mouse and keyboard, PS2 and USB cables, and, in some cases, external USB touchpad cables. Disconnect USB cables and wait for a short time for the device drive…