As we have previously discussed malaria here (see tag "Malaria"), I thought it would be of interest to take a look at the following paper:

Mideo N, Day T. On the evolution of reproductive restraint in malaria. Proc Biol Sci. 2008 Feb 26 (Epub ahead of print, http://dx.doi.org/10.1098/rspb.2007.1545 , requires subscription).

Abstract:
Malaria is one of the leading causes of death among infectious diseases in the world, claiming over one million lives every year. By these standards, this highly complex parasite is extremely successful at generating new infections. Somewhat surprisingly, however, many malaria species seem to invest relatively little in gametocytes, converting only a small percentage of circulating asexual parasite forms into this transmissible form. In this article, we use mathematical models to explore three of the hypotheses that have been proposed to explain this apparent ‘reproductive restraint’ and develop a novel, fourth hypothesis. We find that only one of the previous three hypotheses we explore can explain such low gametocyte conversion rates, and this hypothesis involves a very specific form of density-dependent transmission-blocking immunity. Our fourth hypothesis also provides a potential explanation and is based on the occurrence of multiple infections and the resultant within-host competition between malaria strains that this entails. Further experimental work is needed to determine which of these two hypotheses provides the most likely explanation.

-------- Original Message --------
Subject:
malaria based test kit
Date:
Sat, 23 Feb 2008 20:48:21 +0530
From:
samir somaiya
Hi,

I was a mid-career MPA 2005. At that time, I attended a seminar on
science and technology by Calestous Juma at the Kennedy School.

During that seminar, there was a handout regarding millennium
development goals, and also regarding public health.

Among these, there was discussion on PCR kits, specially for malaria
and other such diseases. Inspired by such discussion,
after returning to India, I sponsored 2 scientists to work on the
development of a PCR kit for malaria, that is specific as well in
determining
the type of malaria. We further partnered with an educational
institution (I am a Trustee here) http://www.somaiya.edu, and we
tested the kits
on the blood samples of suspected malaria patients.

We have since conducted 200 tests, and find that the test is far
superior to the current conventional smear test. The analysis of
the results are enclosed.

Malaria is quite a problem, in Asia as well as India. Do you guys have
any ideas how we can show case this development, so that we can examine
the potential of

making and delivering these tests.

We expect each test to not cost the patient more than $10 (at least in India).

Can you guide? Can this mail go to others in this?

Sincerely

Samir Somaiya

http://news.bbc.co.uk/2/hi/health/6937270.stm

As we continue to create mosquitos that are more and more resistant to anti-malarial agents, this news is really fantastic. I just hope that the environments that the Nile tilapia are entering are also kept in a good balance.

Another point raised by Joanne Greenfield of the WHO is also important... We may not be able to have such fish in areas where there is such shallow water. Still, the numbers of mosquitos reproducing in large bodies is probably greater than that of small pools. I think that this has at least a way of addressing the problem, which may also be more cost effective in the long run...

Malaria: How to Prevent It

What is malaria?

Malaria is an infection that causes high fevers and chills. It's spread by a type of mosquito that feeds at night. The mosquito carries a parasite that causes malaria. If this mosquito bites you, the parasite can get into your blood. The parasite lays eggs, which develop into more parasites, and they feed on your blood cells until you get very sick. Some people die from malaria.

Where is malaria most common?

Malaria is a health problem in many tropical countries. It's also a problem for people visiting these countries. Your chance of getting malaria is highest when you travel in New Guinea, the Solomon Islands, African countries south of the Sahara Desert and some remote places in southeast Asia. Your chance of getting malaria is a little lower in the Caribbean, in the areas around the Amazon River in South America, in India and in some rural areas of Central America. In many countries in Asia and South America, malaria is only in the countryside. If you travel to these countries, you may not need to take malaria medicine if you stay in the malaria-free big cities or take only day trips outside the cities.

How can I protect myself from getting malaria?

You should do whatever you can to keep from getting mosquito bites. If you can, sleep in a room with screens on the windows and doors. Use a mosquito net over your bed. If possible, spray the net with permethrin (one brand name: Elimite). (Permethrin is a spray that repels mosquitos.) During the evening, wear light-colored clothes with long sleeves. It's important to protect yourself with a bug repellant spray that contains no more than 35% of a chemical called "deet." Try not to go outside after the sun sets.

What medicines can I take to prevent malaria?

If you plan to travel to a country where malaria is common, you'll probably take a medicine that may keep you from getting malaria. This is called "prophylactic" malaria medicine. Remember, however, no medicine can protect you 100%.

Prophylactic malaria medicines require you to start taking the medicine a few days or a week before you leave on your trip. You keep taking the medicine during your trip and after your trip for about 1 to 4 weeks, depending on which medicine you are taking. It's important to keep taking the medicine after your trip because the malaria parasites could still be in your blood. Stopping the medicine too soon could give the parasites an opportunity to grow and make you sick. These medicines have some side effects, and not everyone can take them. Your doctor can tell you which medicine is right for you.

Mefloquine (brand name: Lariam) and atovaquone/proguanil (brand name: Malarone) are two medicines you can take. If you can't take one of these, your doctor might recommend you take doxycycline (brand name: Vibramycin). Doxycycline makes you sunburn easily, so you must wear a hat, long sleeves and sunscreen whenever you're outside during the day. Some people can't take this medicine.

If you're traveling to parts of Central America, Haiti or the Middle East, you may be able to take chloroquine (brand name: Aralen). Again, your doctor can tell you which medicine is right for you.

Source

American Academy of Family Physicians
Written by familydoctor.org editorial staff.
http://familydoctor.org/x2500.xml