IS IMMUNITY OF PARASITES PERMANENT?

I have puzzled over a matter for many years. We all know that parasites and viruses become immune to drugs, particularly if the sufferer does not follow the dosage discipline. Immune parasites can pass from host to host.

 

The medical world told us that the malaria parasites are immune to the drugs. In World War 2, the soldiers were dosed with paludrine. Over the next two decades, paludrine was replaced with chloroquine.

 

Then we used fansidar that penetrated the parasite in the liver. Then there was another drug that was an antibiotic doxycycline. These seem to have disappeared at the hands of the multi-national drug barons.

 

Now we have artimeter and artemisin that come from China. But we are told that the virus is slowly becoming immune.

 

We have long learned that immunity comes when sufferers do not follow the prescribed treatment and a residual batch of parasites survive to be immune.

 

I have often wondered what happens with immunity. We are told the parasite can change its genotype to make it impervious to a drug.

 

Does this mean that the parasite is permanently immune to all drugs from the past? through several modifications of genotype? Does the old genotype simply merge with the new genotype to produce a long term phalanyx against anti-malarial drugs?

 

What would happen if the medical powers-that-be went back to paludrine? Or a combination of paludrine-fansidar-doxycline? The parasite would surely not know if it was coming or going.

 

We are told that artimeter is slowly declining in its potency. We now read that artimeter is being combined by the Chinese with another drug.

 

We have the same with the HIV through immunity to the antiretroviral drugs. We know that there are first line drugs to which the sufferer can become immune for the same lack of discipline.

But there is a more expensive second line of drugs about which little seems to have been written on immunity.

 

So too the drugs Rifampicin and Isoniazid for tuberculosis. Perhaps the problem is that there is not a long enough line of drugs like those for malaria. But treatment for TB began in the 1940s. Before then it was a matter of migrating to a hot, dry climate.

 

There was a report in the Papua New Guinea Post Courier newspaper recently on the same subject relating to immunity of the malarial parasite.

 

The point was made that there are countries mainly in the developing world where chloroquine was still being used. What does this mean? Are people dying in the developing world by taking an obsolete drug?

The writer pointed out that chloroquine can be used with a regime of stronger doses. That can be achieved by doubling the dose over morning and night.

Are we to believe a parasite or virus becomes immune to one drug environment but remains immune to other drug environments from the past as well? Clever little buggar.