Science Roundup

Here are a couple of infectious disease related stories that caught my attention on Science Daily today.

Malaria Researchers Identify New Mosquito Virus
Researchers at the Johns Hopkins Bloomberg School of Public Health's Malaria Research Institute have identified a previously unknown virus that is infectious to Anopheles gambiae—the mosquito primarily responsible for transmitting malaria.

Although the virus does not appear to harm the mosquitoes, the researchers determined it is highly infectious to mosquito larvae and is easily passed on to the adults.

In theory, we could use this virus to produce a lethal toxin in the mosquito or instruct the mosquito to die after 10 days, which is before it can transmit the malaria parasite to humans. However, these concepts are many years away.

Some Cells Self-destruct For The Greater Common Good.
'(R)andom molecular processes during cell division allow some cells to engage in a self-destructive act to generate a greater common good, thereby improving the situation of the surviving siblings.'

Normally, salmonellae grow poorly in the intestine because they are not competitive with other bacteria of the gut. However, this dynamic changes if salmonellae induce an inflammatory response, namely diarrhoea, which suppresses the other bacteria. The inflammation is triggered by salmonellae penetrating into the intestinal tissues. Once inside, salmonellae is killed by the immune system. This in turn creates a conflict: salmonellae are either suppressed by the other bacteria in the gut, or die while trying to eliminate these competitors.

As Ackermann, Hardt and Doebeli report, salmonellae have found a surprising solution to this conflict. Inside the gut, the samonella bacteria forms two groups that engage in job-sharing. A first group invades the tissue, triggers an inflammation, then dies. A second group waits inside the gut until the inactivation of the normal intestinal flora gives them an opportunity to strike. This second group then multiplies unhindered.

(Barely) Relevant material previously on the blog:
Book recommendations
Dengue fever
Zoonoses as Biological Weapons